Use a dropdown and a Create ticket button on the ticket panel, in orange

The panel is now one category dropdown and a Create ticket button
instead of a button per category. Discord doesn't send the dropdown's
value with a button click, so each member's pick is remembered in
memory for 15 minutes (per guild and member, capped). Panels posted
before keep working until they're reposted. Every ticket embed is
orange, closed tickets included.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

README.md

@@ -10,6 +10,7 @@ It currently includes:
 - Scheduling (1:1 sessions with DM invites + reaction-based accept/decline/reschedule)
 - Projects (list/create projects + helpers)
 - Support tickets (a panel with categories, a private thread per ticket, claim/close, transcripts to a log channel)
+- Anti-raid and anti-nuke (Join Gate, raid mode, quarantine of anyone who mass-deletes or mass-bans, lockdowns), modelled on Wick
 - Music (Lavalink-powered `/play`, `/queue`, `/volume`)
 - Twitch live notifications (per-guild `/config` setup)
 - Welcome messages, DMs, and default role assignment (per-guild `/config` setup)
@@ -101,10 +102,22 @@ just down    # stop postgres
   - `/projects list`, `/projects create`, `/projects add-helper`
 - **Tickets**
   - `/tickets setup channel:#tickets [log-channel] [staff-role]` — Where tickets open and closed ones are logged (**Manage Server**)
-  - `/tickets category add|remove|list` — One panel button per category, each with its own staff role (**Manage Server**)
+  - `/tickets category add|remove|list` — One entry in the panel's dropdown per category, each with its own staff role (**Manage Server**)
   - `/tickets panel` — Post or refresh the panel (**Manage Server**)
   - `/ticket add`, `/ticket close [reason]` — Opener or staff; `/ticket claim`, `/ticket remove` — staff
   - The bot needs View Channel, Send Messages, Embed Links, Create Private Threads, Send Messages in Threads and Manage Threads in the ticket channel, and Attach Files in the log channel. Give the staff role Manage Threads there too, so staff see every ticket.
+- **Security** (anti-raid and anti-nuke; everything is off until turned on)
+  - `/security status`, `/security toggle feature on`, `/security alerts channel [role]`
+  - `/security trust add|remove user|role` — owner only; trusted members are exempt from anti-nuke and may change security settings
+  - `/security release user`, `/security quarantined`, `/security end-raid`, `/security quarantine-role`
+  - `/lockdown channel|server|joins`, `/unlock channel|server|joins` — unlocking needs the owner or a trusted member
+  - `/security snapshot`, `/security restore` — snapshots of roles and channels are also taken every 6 hours while anti-nuke is on (last three kept); restore recreates deleted roles and channels and reverts dangerous permission changes, and can run automatically after a stopped nuke
+  - Heat (anti-spam): messages build a per-member score that cools over time; spam, repeats, mass mentions and invite links max it, which deletes the message and times the member out (doubling for repeat offences). A wave of spammers turns on heat panic (newcomers timed out on sight for 10 minutes); a mention flood can lock the server. Moderators (Manage Messages) and trusted members are exempt.
+  - Raid mode survives a bot restart.
+  - Critical alerts (raids, stopped nukes, restores, spam waves, removed bots) are also DMed to the owner and trusted users (up to 10; trusted roles aren't expanded), since the alert channel may be the first thing a nuker deletes. One setting turns this off.
+  - Join Gate filters, raid thresholds, anti-nuke limits and heat settings are set on the dashboard.
+  - The bot needs View Audit Log, Manage Roles, Manage Channels, Manage Server (to pause invites), Moderate Members, Kick Members and Ban Members, and its role must be above the roles it protects against: it can only quarantine members whose highest role is below its own.
+  - Turning things off, unlocking and releasing always need the owner or someone on the trusted list, whatever Discord's command permissions say.
 - **Music** (requires **DJ** role)
   - `/play`, `/queue`, `/volume`
 - **Moderation** (focused + practical)

internal/bot/bot.go

@@ -10,6 +10,7 @@ import (
 	"velox-bot/internal/events"
 	"velox-bot/internal/music"
 	"velox-bot/internal/tickets"
+	"velox-bot/internal/security"
 
 	"github.com/bwmarrin/discordgo"
 )
@@ -84,6 +85,24 @@ func (b *Bot) Start() error {
 		}()
 	}
 
+	if eng := security.Start(b.Session, b.Session.State.User.ID); eng != nil {
+		// Moderators are exempt from heat; their permissions come from the
+		// gateway cache so a message never costs an API call.
+		eng.ChannelPerms = b.Session.State.UserChannelPermissions
+		eng.ResumeRaids(context.Background())
+		go eng.WatchRaids(context.Background(), 30*time.Second)
+		go eng.WatchSnapshots(context.Background())
+		go func() {
+			// Reconnect if the database connection drops, instead of
+			// silently ignoring the dashboard from then on.
+			for {
+				err := eng.StartCommandListener(context.Background(), b.DBHost)
+				log.Printf("security: command listener stopped: %v (retrying in 10s)", err)
+				time.Sleep(10 * time.Second)
+			}
+		}()
+	}
+
 	b.registeredCommands = make([]*discordgo.ApplicationCommand, len(b.Commands))
 	for _, cmd := range b.Commands {
 		created, err := b.Session.ApplicationCommandCreate(b.AppID, b.GuildID, cmd)
@@ -97,12 +116,24 @@ func (b *Bot) Start() error {
 	b.Session.AddHandler(commands.HandleInteraction)
 
 	b.Session.AddHandler(func(s *discordgo.Session, m *discordgo.MessageCreate) {
+		if eng := security.Default(); eng != nil {
+			eng.OnMessage(context.Background(), m)
+		}
 		events.HandleMessageCreate(s, m, b.Services)
 	})
 
 	b.Session.AddHandler(func(s *discordgo.Session, m *discordgo.GuildMemberAdd) {
 		events.HandleBotAddedOnGuild(s, m, b.Services)
 
+		// Security runs first: someone it removes (join lock, Join Gate,
+		// raid) gets no welcome message or default role.
+		if eng := security.Default(); eng != nil && m != nil && m.Member != nil {
+			if eng.OnMemberJoin(context.Background(), m.GuildID, m.Member) {
+				events.HandleGuildMemberAddLog(s, m, b.Services)
+				return
+			}
+		}
+
 		// Ignore bot members for welcome/log onboarding of normal users.
 		if m != nil && m.Member != nil && m.User != nil && m.User.Bot {
 			return
@@ -112,6 +143,14 @@ func (b *Bot) Start() error {
 		events.HandleGuildMemberAddLog(s, m, b.Services)
 	})
 
+	// Anti-nuke and unauthorized bot additions read the audit log as it
+	// happens (needs the Guild Moderation intent and View Audit Log).
+	b.Session.AddHandler(func(s *discordgo.Session, ev *discordgo.GuildAuditLogEntryCreate) {
+		if eng := security.Default(); eng != nil && ev.AuditLogEntry != nil {
+			eng.OnAuditLogEntry(context.Background(), ev.GuildID, ev.AuditLogEntry)
+		}
+	})
+
 	b.Session.AddHandler(func(s *discordgo.Session, m *discordgo.GuildMemberRemove) {
 		events.HandleGuildMemberRemoveLog(s, m, b.Services)
 	})

internal/commands/commands.go

@@ -12,6 +12,7 @@ import (
 	"velox-bot/internal/commands/projects"
 	"velox-bot/internal/commands/schedule"
 	cmdtickets "velox-bot/internal/commands/tickets"
+	cmdsecurity "velox-bot/internal/commands/security"
 	"velox-bot/internal/commands/timezone"
 	"velox-bot/internal/music"
 
@@ -43,6 +44,9 @@ var AllCommands = []*discordgo.ApplicationCommand{
 	config.Config,
 	cmdtickets.Tickets,
 	cmdtickets.Ticket,
+	cmdsecurity.Security,
+	cmdsecurity.Lockdown,
+	cmdsecurity.Unlock,
 }
 
 var handlers = map[string]func(s *discordgo.Session, i *discordgo.InteractionCreate){
@@ -70,6 +74,9 @@ var handlers = map[string]func(s *discordgo.Session, i *discordgo.InteractionCre
 	"config":         config.ConfigHandler,
 	"tickets":        cmdtickets.TicketsHandler,
 	"ticket":         cmdtickets.TicketHandler,
+	"security":       cmdsecurity.SecurityHandler,
+	"lockdown":       cmdsecurity.LockdownHandler,
+	"unlock":         cmdsecurity.UnlockHandler,
 }
 
 func HandleInteraction(s *discordgo.Session, i *discordgo.InteractionCreate) {
@@ -89,6 +96,8 @@ func HandleInteraction(s *discordgo.Session, i *discordgo.InteractionCreate) {
 			projects.HandleComponent(s, i)
 		case strings.HasPrefix(data.CustomID, "tickets:"):
 			cmdtickets.HandleComponent(s, i)
+		case strings.HasPrefix(data.CustomID, "security:"):
+			cmdsecurity.HandleComponent(s, i)
 		}
 	case discordgo.InteractionModalSubmit:
 		data := i.ModalSubmitData()

internal/commands/help/help.go

@@ -93,6 +93,16 @@ func HelpHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
 					"`/ticket claim`, `/ticket remove user:@someone` — Staff only\n" +
 					"`/tickets setup`, `/tickets category add|remove|list`, `/tickets panel` — Set up (**Manage Server**)",
 			},
+			{
+				Name: "Security (anti-raid & anti-nuke)",
+				Value: "" +
+					"`/security status` — What's on and who is trusted\n" +
+					"`/security toggle` — Join Gate, raid mode, anti-nuke on/off (off: owner or trusted)\n" +
+					"`/security alerts`, `/security quarantine-role`, `/security release`, `/security end-raid` — Owner or trusted\n" +
+					"`/security trust add|remove` — Owner only\n" +
+					"`/security snapshot` — Save roles and channels; `/security restore` — Rebuild what a nuke deleted (owner or trusted)\n" +
+					"`/lockdown channel|server|joins`, `/unlock …` (unlock: owner or trusted)",
+			},
 			{
 				Name: "Meetings (**Manage Server**)",
 				Value: "" +

internal/commands/security/public/security.go

@@ -0,0 +1,575 @@
+package public
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"strings"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+	"velox-bot/internal/security"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Every handler re-checks permissions through the security engine. The
+// DefaultMemberPermissions below only hide commands from the menu; server
+// admins can change them, so they are never what keeps anyone out.
+
+var (
+	manageGuild   = int64(discordgo.PermissionManageGuild)
+	manageChannel = int64(discordgo.PermissionManageChannels)
+	guildOnly     = &[]discordgo.InteractionContextType{discordgo.InteractionContextGuild}
+	textChannels  = []discordgo.ChannelType{discordgo.ChannelTypeGuildText, discordgo.ChannelTypeGuildNews}
+	chatChannels  = []discordgo.ChannelType{
+		discordgo.ChannelTypeGuildText, discordgo.ChannelTypeGuildNews, discordgo.ChannelTypeGuildForum,
+		discordgo.ChannelTypeGuildVoice, discordgo.ChannelTypeGuildStageVoice,
+	}
+	opTimeout     = 3 * time.Minute
+	genericFailed = "Something went wrong. Check that Velox's role is high enough and has the permissions it needs, then try again."
+)
+
+var featureChoices = []*discordgo.ApplicationCommandOptionChoice{
+	{Name: "Join Gate", Value: securityrepo.FeatureJoinGate},
+	{Name: "Raid mode", Value: securityrepo.FeatureAntiRaid},
+	{Name: "Anti-nuke", Value: securityrepo.FeatureAntiNuke},
+	{Name: "Heat (anti-spam)", Value: securityrepo.FeatureHeat},
+}
+
+var Security = &discordgo.ApplicationCommand{
+	Name:                     "security",
+	Description:              "Anti-raid and anti-nuke protection",
+	DefaultMemberPermissions: &manageGuild,
+	Contexts:                 guildOnly,
+	Options: []*discordgo.ApplicationCommandOption{
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "status", Description: "Show what's on and who is trusted"},
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommand, Name: "toggle", Description: "Turn a protection on or off",
+			Options: []*discordgo.ApplicationCommandOption{
+				{Type: discordgo.ApplicationCommandOptionString, Name: "feature", Description: "Which protection", Required: true, Choices: featureChoices},
+				{Type: discordgo.ApplicationCommandOptionBoolean, Name: "on", Description: "On or off", Required: true},
+			},
+		},
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommand, Name: "alerts", Description: "Where alerts go and which role they ping (owner or trusted)",
+			Options: []*discordgo.ApplicationCommandOption{
+				{Type: discordgo.ApplicationCommandOptionChannel, Name: "channel", Description: "Alert channel", Required: true, ChannelTypes: textChannels},
+				{Type: discordgo.ApplicationCommandOptionRole, Name: "role", Description: "Role to ping for raids and nukes"},
+			},
+		},
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommand, Name: "quarantine-role", Description: "Role given to quarantined members (owner or trusted)",
+			Options: []*discordgo.ApplicationCommandOption{
+				{Type: discordgo.ApplicationCommandOptionRole, Name: "role", Description: "Leave empty to use none"},
+			},
+		},
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommandGroup, Name: "trust", Description: "Who is exempt from anti-nuke (owner only)",
+			Options: []*discordgo.ApplicationCommandOption{
+				{
+					Type: discordgo.ApplicationCommandOptionSubCommand, Name: "add", Description: "Trust a user or a role",
+					Options: []*discordgo.ApplicationCommandOption{
+						{Type: discordgo.ApplicationCommandOptionUser, Name: "user", Description: "A user"},
+						{Type: discordgo.ApplicationCommandOptionRole, Name: "role", Description: "A role"},
+					},
+				},
+				{
+					Type: discordgo.ApplicationCommandOptionSubCommand, Name: "remove", Description: "Stop trusting a user or a role",
+					Options: []*discordgo.ApplicationCommandOption{
+						{Type: discordgo.ApplicationCommandOptionUser, Name: "user", Description: "A user"},
+						{Type: discordgo.ApplicationCommandOptionRole, Name: "role", Description: "A role"},
+					},
+				},
+			},
+		},
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommand, Name: "release", Description: "Release a quarantined member (owner or trusted)",
+			Options: []*discordgo.ApplicationCommandOption{
+				{Type: discordgo.ApplicationCommandOptionUser, Name: "user", Description: "Who to release", Required: true},
+			},
+		},
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "quarantined", Description: "List quarantined members"},
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "end-raid", Description: "End raid mode now (owner or trusted)"},
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "snapshot", Description: "Save a snapshot of roles and channels to restore from"},
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "restore", Description: "Recreate deleted roles and channels from the latest snapshot (owner or trusted)"},
+	},
+}
+
+func lockOptions(unlock bool) []*discordgo.ApplicationCommandOption {
+	verb := "Lock"
+	if unlock {
+		verb = "Unlock"
+	}
+	joins := &discordgo.ApplicationCommandOption{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "joins", Description: verb + " joins"}
+	if !unlock {
+		joins.Description = "Kick or ban everyone who joins until unlocked"
+		joins.Options = []*discordgo.ApplicationCommandOption{{
+			Type: discordgo.ApplicationCommandOptionString, Name: "action", Description: "What happens to new members", Required: true,
+			Choices: []*discordgo.ApplicationCommandOptionChoice{{Name: "Kick", Value: securityrepo.ActionKick}, {Name: "Ban", Value: securityrepo.ActionBan}},
+		}}
+	}
+	return []*discordgo.ApplicationCommandOption{
+		{
+			Type: discordgo.ApplicationCommandOptionSubCommand, Name: "channel", Description: verb + " one channel",
+			Options: []*discordgo.ApplicationCommandOption{{Type: discordgo.ApplicationCommandOptionChannel, Name: "channel", Description: "Defaults to this channel", ChannelTypes: chatChannels}},
+		},
+		{Type: discordgo.ApplicationCommandOptionSubCommand, Name: "server", Description: verb + " every channel"},
+		joins,
+	}
+}
+
+var Lockdown = &discordgo.ApplicationCommand{
+	Name: "lockdown", Description: "Stop members from talking, or from joining", DefaultMemberPermissions: &manageChannel,
+	Contexts: guildOnly, Options: lockOptions(false),
+}
+
+var Unlock = &discordgo.ApplicationCommand{
+	Name: "unlock", Description: "Undo a lockdown (owner or trusted)", DefaultMemberPermissions: &manageChannel,
+	Contexts: guildOnly, Options: lockOptions(true),
+}
+
+func reply(s *discordgo.Session, i *discordgo.InteractionCreate, msg string) {
+	_ = s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
+		Type: discordgo.InteractionResponseChannelMessageWithSource,
+		Data: &discordgo.InteractionResponseData{Content: msg, Flags: discordgo.MessageFlagsEphemeral, AllowedMentions: &discordgo.MessageAllowedMentions{}},
+	})
+}
+
+func deferReply(s *discordgo.Session, i *discordgo.InteractionCreate) bool {
+	return s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
+		Type: discordgo.InteractionResponseDeferredChannelMessageWithSource,
+		Data: &discordgo.InteractionResponseData{Flags: discordgo.MessageFlagsEphemeral},
+	}) == nil
+}
+
+func edit(s *discordgo.Session, i *discordgo.InteractionCreate, msg string) {
+	_, _ = s.InteractionResponseEdit(i.Interaction, &discordgo.WebhookEdit{Content: &msg, AllowedMentions: &discordgo.MessageAllowedMentions{}})
+}
+
+func message(where string, err error) string {
+	var ue security.UserError
+	if errors.As(err, &ue) {
+		return string(ue)
+	}
+	log.Printf("security command %s: %v", where, err)
+	return genericFailed
+}
+
+func opts(o []*discordgo.ApplicationCommandInteractionDataOption) map[string]*discordgo.ApplicationCommandInteractionDataOption {
+	m := map[string]*discordgo.ApplicationCommandInteractionDataOption{}
+	for _, x := range o {
+		m[x.Name] = x
+	}
+	return m
+}
+
+func perms(i *discordgo.InteractionCreate) int64 {
+	if i.Member == nil {
+		return 0
+	}
+	return i.Member.Permissions
+}
+
+func userID(i *discordgo.InteractionCreate) string {
+	if i.Member == nil || i.Member.User == nil {
+		return ""
+	}
+	return i.Member.User.ID
+}
+
+func engine(s *discordgo.Session, i *discordgo.InteractionCreate) *security.Engine {
+	e := security.Default()
+	if e == nil || i.GuildID == "" || i.Member == nil {
+		reply(s, i, "Security isn't available right now.")
+		return nil
+	}
+	return e
+}
+
+// allowedOrTrusted lets an action through when the member has one of the
+// permissions, or is the owner or trusted.
+func allowedOrTrusted(ctx context.Context, e *security.Engine, i *discordgo.InteractionCreate, need int64) bool {
+	if perms(i)&(need|discordgo.PermissionAdministrator) != 0 {
+		return true
+	}
+	return e.RequireTrusted(ctx, i.GuildID, i.Member) == nil
+}
+
+func SecurityHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	e := engine(s, i)
+	if e == nil {
+		return
+	}
+	data := i.ApplicationCommandData()
+	if len(data.Options) == 0 {
+		return
+	}
+	sub := data.Options[0]
+	args := opts(sub.Options)
+	ctx, cancel := context.WithTimeout(context.Background(), opTimeout)
+	defer cancel()
+
+	switch sub.Name {
+	case "status":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageGuild) {
+			reply(s, i, "You need Manage Server to see the security settings.")
+			return
+		}
+		reply(s, i, status(ctx, e, i.GuildID))
+	case "toggle":
+		feature, on := args["feature"].StringValue(), args["on"].BoolValue()
+		if err := e.SetFeature(ctx, i.GuildID, i.Member, perms(i), feature, on); err != nil {
+			reply(s, i, message("toggle", err))
+			return
+		}
+		state := "off"
+		if on {
+			state = "on"
+		}
+		reply(s, i, fmt.Sprintf("%s is now **%s**.", featureName(feature), state))
+	case "alerts":
+		ch := args["channel"].ChannelValue(nil).ID
+		role := ""
+		if r, ok := args["role"]; ok {
+			role = r.RoleValue(nil, i.GuildID).ID
+		}
+		if err := e.SetAlerts(ctx, i.GuildID, i.Member, ch, role); err != nil {
+			reply(s, i, message("alerts", err))
+			return
+		}
+		reply(s, i, fmt.Sprintf("Alerts will go to <#%s>.", ch))
+	case "quarantine-role":
+		role := ""
+		if r, ok := args["role"]; ok {
+			role = r.RoleValue(nil, i.GuildID).ID
+		}
+		if err := e.SetQuarantineRole(ctx, i.GuildID, i.Member, role); err != nil {
+			reply(s, i, message("quarantine-role", err))
+			return
+		}
+		if role == "" {
+			reply(s, i, "Quarantined members won't get a role; they still lose their roles and are timed out.")
+		} else {
+			reply(s, i, fmt.Sprintf("Quarantined members will get <@&%s>.", role))
+		}
+	case "trust":
+		if len(sub.Options) == 0 {
+			return
+		}
+		handleTrust(ctx, s, i, e, sub.Options[0])
+	case "release":
+		if err := e.RequireTrusted(ctx, i.GuildID, i.Member); err != nil {
+			reply(s, i, message("release", err))
+			return
+		}
+		target := args["user"].UserValue(nil)
+		if !deferReply(s, i) {
+			return
+		}
+		if err := e.Release(ctx, i.GuildID, target.ID, userID(i)); err != nil {
+			edit(s, i, message("release", err))
+			return
+		}
+		edit(s, i, fmt.Sprintf("<@%s> was released and got their roles back.", target.ID))
+	case "quarantined":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageGuild) {
+			reply(s, i, "You need Manage Server to see this.")
+			return
+		}
+		qs, err := e.Quarantines(ctx, i.GuildID)
+		if err != nil {
+			reply(s, i, message("quarantined", err))
+			return
+		}
+		if len(qs) == 0 {
+			reply(s, i, "Nobody is quarantined.")
+			return
+		}
+		var b strings.Builder
+		for _, q := range qs {
+			fmt.Fprintf(&b, "• <@%d>, <t:%d:R>: %s\n", q.UserID, q.CreatedAt.Unix(), q.Reason)
+		}
+		reply(s, i, clip(b.String(), 1900))
+	case "end-raid":
+		endRaid(ctx, s, i, e)
+	case "snapshot":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageGuild) {
+			reply(s, i, "You need Manage Server to take a snapshot.")
+			return
+		}
+		if !deferReply(s, i) {
+			return
+		}
+		roles, channels, err := e.TakeSnapshot(ctx, i.GuildID, userID(i))
+		if err != nil {
+			edit(s, i, message("snapshot", err))
+			return
+		}
+		edit(s, i, fmt.Sprintf("Snapshot saved: %d roles and %d channels. The last three are kept.", roles, channels))
+	case "restore":
+		if err := e.RequireTrusted(ctx, i.GuildID, i.Member); err != nil {
+			reply(s, i, message("restore", err))
+			return
+		}
+		if !deferReply(s, i) {
+			return
+		}
+		// Recreating many channels takes a while under Discord's rate limits.
+		res, err := e.Restore(ctx, i.GuildID, userID(i))
+		if err != nil {
+			edit(s, i, message("restore", err))
+			return
+		}
+		edit(s, i, fmt.Sprintf("Restored from the snapshot of <t:%d:f>: %d roles and %d channels recreated, %d roles had dangerous permissions reverted, %d steps failed.",
+			res.SnapshotAt.Unix(), res.RolesCreated, res.ChannelsCreated, res.RolesReverted, res.Failed))
+	}
+}
+
+func handleTrust(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate, e *security.Engine, sub *discordgo.ApplicationCommandInteractionDataOption) {
+	args := opts(sub.Options)
+	kind, target := "", ""
+	if u, ok := args["user"]; ok {
+		kind, target = "user", u.UserValue(nil).ID
+	}
+	if r, ok := args["role"]; ok {
+		if target != "" {
+			reply(s, i, "Pick a user or a role, not both.")
+			return
+		}
+		kind, target = "role", r.RoleValue(nil, i.GuildID).ID
+	}
+	if target == "" {
+		reply(s, i, "Pick a user or a role.")
+		return
+	}
+	mention := "<@" + target + ">"
+	if kind == "role" {
+		mention = "<@&" + target + ">"
+	}
+	switch sub.Name {
+	case "add":
+		if err := e.Trust(ctx, i.GuildID, i.Member, kind, target); err != nil {
+			reply(s, i, message("trust add", err))
+			return
+		}
+		reply(s, i, mention+" is now trusted: exempt from anti-nuke and able to change security settings.")
+	case "remove":
+		if err := e.Untrust(ctx, i.GuildID, i.Member, target); err != nil {
+			reply(s, i, message("trust remove", err))
+			return
+		}
+		reply(s, i, mention+" is no longer trusted.")
+	}
+}
+
+func endRaid(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate, e *security.Engine) {
+	if err := e.RequireTrusted(ctx, i.GuildID, i.Member); err != nil {
+		reply(s, i, message("end raid", err))
+		return
+	}
+	if !deferReply(s, i) {
+		return
+	}
+	if err := e.EndRaid(ctx, i.GuildID, userID(i)); err != nil {
+		edit(s, i, message("end raid", err))
+		return
+	}
+	edit(s, i, "Raid mode is off.")
+}
+
+func featureName(f string) string {
+	switch f {
+	case securityrepo.FeatureJoinGate:
+		return "Join Gate"
+	case securityrepo.FeatureAntiRaid:
+		return "Raid mode"
+	case securityrepo.FeatureAntiNuke:
+		return "Anti-nuke"
+	case securityrepo.FeatureHeat:
+		return "Heat"
+	}
+	return f
+}
+
+func onOff(b bool) string {
+	if b {
+		return "✅ on"
+	}
+	return "⬜ off"
+}
+
+func status(ctx context.Context, e *security.Engine, guildID string) string {
+	st, trusted, err := e.Settings(ctx, guildID)
+	if err != nil {
+		return message("status", err)
+	}
+	var b strings.Builder
+	fmt.Fprintf(&b, "**Join Gate:** %s\n**Raid mode:** %s (%d joins in %ds → %s)\n**Anti-nuke:** %s (auto restore %s)\n**Heat:** %s (%s)\n",
+		onOff(st.JoinGateEnabled), onOff(st.AntiRaidEnabled), st.RaidJoinCount, st.RaidJoinSeconds, st.RaidAction,
+		onOff(st.AntiNukeEnabled), onOff(st.AntiNukeAutoRestore), onOff(st.HeatEnabled), st.HeatStrictness)
+	if e.RaidActive(guildID) {
+		b.WriteString("🚨 **A raid is in progress.**\n")
+	}
+	if st.JoinLock != securityrepo.ActionOff {
+		fmt.Fprintf(&b, "🔒 Joins are locked (%s).\n", st.JoinLock)
+	}
+	if st.AlertChannelID != 0 {
+		fmt.Fprintf(&b, "**Alerts:** <#%d>", st.AlertChannelID)
+		if st.AlertRoleID != 0 {
+			fmt.Fprintf(&b, ", pinging <@&%d>", st.AlertRoleID)
+		}
+		b.WriteString("\n")
+	} else {
+		b.WriteString("**Alerts:** not set. Use `/security alerts`.\n")
+	}
+	if owner, err := e.OwnerID(guildID); err == nil {
+		fmt.Fprintf(&b, "**Trusted:** <@%s> (owner)", owner)
+	}
+	for _, t := range trusted {
+		if t.Kind == "role" {
+			fmt.Fprintf(&b, ", <@&%d>", t.TargetID)
+		} else {
+			fmt.Fprintf(&b, ", <@%d>", t.TargetID)
+		}
+	}
+	b.WriteString("\nFine-tune filters, limits and actions on the dashboard.")
+	return b.String()
+}
+
+func clip(s string, n int) string {
+	if r := []rune(s); len(r) > n {
+		return string(r[:n-1]) + "…"
+	}
+	return s
+}
+
+func LockdownHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	e := engine(s, i)
+	if e == nil {
+		return
+	}
+	data := i.ApplicationCommandData()
+	if len(data.Options) == 0 {
+		return
+	}
+	sub := data.Options[0]
+	args := opts(sub.Options)
+	ctx, cancel := context.WithTimeout(context.Background(), opTimeout)
+	defer cancel()
+
+	switch sub.Name {
+	case "channel":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageChannels) {
+			reply(s, i, "You need Manage Channels to lock a channel.")
+			return
+		}
+		ch := i.ChannelID
+		if c, ok := args["channel"]; ok {
+			ch = c.ChannelValue(nil).ID
+		}
+		if err := e.LockChannel(ctx, i.GuildID, ch, userID(i), false); err != nil {
+			reply(s, i, message("lock channel", err))
+			return
+		}
+		reply(s, i, fmt.Sprintf("🔒 <#%s> is locked. `/unlock channel` puts it back as it was.", ch))
+	case "server":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageGuild) {
+			reply(s, i, "You need Manage Server to lock the server.")
+			return
+		}
+		if !deferReply(s, i) {
+			return
+		}
+		locked, failed, err := e.LockServer(ctx, i.GuildID, userID(i))
+		if err != nil {
+			edit(s, i, message("lock server", err))
+			return
+		}
+		msg := fmt.Sprintf("🔒 Locked %d channels.", locked)
+		if failed > 0 {
+			msg += fmt.Sprintf(" %d couldn't be locked (Velox needs Manage Channels there).", failed)
+		}
+		edit(s, i, msg+" `/unlock server` puts them back as they were.")
+	case "joins":
+		if !allowedOrTrusted(ctx, e, i, discordgo.PermissionManageGuild) {
+			reply(s, i, "You need Manage Server to lock joins.")
+			return
+		}
+		mode := args["action"].StringValue()
+		if err := e.SetJoinLock(ctx, i.GuildID, mode, userID(i)); err != nil {
+			reply(s, i, message("lock joins", err))
+			return
+		}
+		reply(s, i, fmt.Sprintf("🔒 Everyone who joins will be %s until `/unlock joins`.", map[string]string{"kick": "kicked", "ban": "banned"}[mode]))
+	}
+}
+
+// UnlockHandler relaxes protection, so it is owner or trusted only.
+func UnlockHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	e := engine(s, i)
+	if e == nil {
+		return
+	}
+	data := i.ApplicationCommandData()
+	if len(data.Options) == 0 {
+		return
+	}
+	sub := data.Options[0]
+	args := opts(sub.Options)
+	ctx, cancel := context.WithTimeout(context.Background(), opTimeout)
+	defer cancel()
+	if err := e.RequireTrusted(ctx, i.GuildID, i.Member); err != nil {
+		reply(s, i, message("unlock", err))
+		return
+	}
+
+	switch sub.Name {
+	case "channel":
+		ch := i.ChannelID
+		if c, ok := args["channel"]; ok {
+			ch = c.ChannelValue(nil).ID
+		}
+		if err := e.UnlockChannel(ctx, i.GuildID, ch, userID(i)); err != nil {
+			reply(s, i, message("unlock channel", err))
+			return
+		}
+		reply(s, i, fmt.Sprintf("🔓 <#%s> is unlocked.", ch))
+	case "server":
+		if !deferReply(s, i) {
+			return
+		}
+		unlocked, failed, err := e.UnlockServer(ctx, i.GuildID, userID(i))
+		if err != nil {
+			edit(s, i, message("unlock server", err))
+			return
+		}
+		msg := fmt.Sprintf("🔓 Unlocked %d channels.", unlocked)
+		if failed > 0 {
+			msg += fmt.Sprintf(" %d failed; try `/unlock server` again.", failed)
+		}
+		edit(s, i, msg)
+	case "joins":
+		if err := e.SetJoinLock(ctx, i.GuildID, securityrepo.ActionOff, userID(i)); err != nil {
+			reply(s, i, message("unlock joins", err))
+			return
+		}
+		reply(s, i, "🔓 Joins are open again.")
+	}
+}
+
+// HandleComponent handles the alert's "End raid" button. Anyone in the alert
+// channel can press it, so it checks trust like the command.
+func HandleComponent(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	e := engine(s, i)
+	if e == nil {
+		return
+	}
+	if i.MessageComponentData().CustomID != security.CustomIDEndRaid {
+		return
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), opTimeout)
+	defer cancel()
+	endRaid(ctx, s, i, e)
+}

internal/commands/security/registry.go

@@ -0,0 +1,29 @@
+package security
+
+import (
+	"velox-bot/internal/commands/security/public"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+var (
+	Security *discordgo.ApplicationCommand = public.Security
+	Lockdown *discordgo.ApplicationCommand = public.Lockdown
+	Unlock   *discordgo.ApplicationCommand = public.Unlock
+)
+
+func SecurityHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	public.SecurityHandler(s, i)
+}
+
+func LockdownHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	public.LockdownHandler(s, i)
+}
+
+func UnlockHandler(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	public.UnlockHandler(s, i)
+}
+
+func HandleComponent(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	public.HandleComponent(s, i)
+}

internal/commands/tickets/public/tickets.go

@@ -60,7 +60,7 @@ var Tickets = &discordgo.ApplicationCommand{
 				{
 					Type:        discordgo.ApplicationCommandOptionSubCommand,
 					Name:        "add",
-					Description: "Add a category (one button on the panel)",
+					Description: "Add a category (an option in the panel's dropdown)",
 					Options: []*discordgo.ApplicationCommandOption{
 						{Type: discordgo.ApplicationCommandOptionString, Name: "name", Description: "e.g. Support, Report, Appeal", Required: true, MaxLength: 40},
 						{Type: discordgo.ApplicationCommandOptionRole, Name: "staff-role", Description: "Who handles these tickets"},
@@ -424,7 +424,7 @@ func closeTicket(s *discordgo.Session, i *discordgo.InteractionCreate, reason st
 	edit(s, i, "Ticket closed.")
 }
 
-// HandleComponent handles the panel buttons and dropdown and the Claim and
+// HandleComponent handles the panel dropdown and Create ticket button and the Claim and
 // Close buttons in a ticket.
 func HandleComponent(s *discordgo.Session, i *discordgo.InteractionCreate) {
 	if Repo == nil {
@@ -434,9 +434,12 @@ func HandleComponent(s *discordgo.Session, i *discordgo.InteractionCreate) {
 	data := i.MessageComponentData()
 	switch {
 	case strings.HasPrefix(data.CustomID, "tickets:open:"):
+		// Panels posted before the dropdown had one button per category.
 		showOpenForm(s, i, strings.TrimPrefix(data.CustomID, "tickets:open:"))
 	case data.CustomID == "tickets:select" && len(data.Values) > 0:
-		showOpenForm(s, i, data.Values[0])
+		rememberPick(s, i, data.Values[0])
+	case data.CustomID == "tickets:create":
+		createFromPick(s, i)
 	case data.CustomID == "tickets:claim":
 		claim(s, i)
 	case data.CustomID == "tickets:close":
@@ -450,6 +453,31 @@ func HandleComponent(s *discordgo.Session, i *discordgo.InteractionCreate) {
 	}
 }
 
+// rememberPick stores the dropdown choice for the Create ticket button and
+// acknowledges it without changing the panel, so the choice stays visible.
+func rememberPick(s *discordgo.Session, i *discordgo.InteractionCreate, rawCategory string) {
+	catID, err := strconv.ParseInt(rawCategory, 10, 64)
+	if err != nil || i.Member == nil || i.Member.User == nil {
+		return
+	}
+	userID, _ := strconv.ParseInt(i.Member.User.ID, 10, 64)
+	tickets.RememberPick(guildID(i), userID, catID)
+	_ = s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{Type: discordgo.InteractionResponseDeferredMessageUpdate})
+}
+
+func createFromPick(s *discordgo.Session, i *discordgo.InteractionCreate) {
+	if i.Member == nil || i.Member.User == nil {
+		return
+	}
+	userID, _ := strconv.ParseInt(i.Member.User.ID, 10, 64)
+	catID, ok := tickets.PickedCategory(guildID(i), userID)
+	if !ok {
+		reply(s, i, "Pick a category from the menu first, then press **Create ticket**.")
+		return
+	}
+	showOpenForm(s, i, strconv.FormatInt(catID, 10))
+}
+
 func showOpenForm(s *discordgo.Session, i *discordgo.InteractionCreate, rawCategory string) {
 	catID, err := strconv.ParseInt(rawCategory, 10, 64)
 	if err != nil || i.Member == nil || i.Member.User == nil {

internal/db/repos/securityrepo/repo.go

@@ -0,0 +1,584 @@
+// Package securityrepo stores the anti-raid and anti-nuke settings, the
+// trusted list, quarantines, locked channels, the event history and the
+// dashboard's requests. Discord IDs are int64; 0 means "not set".
+package securityrepo
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"errors"
+	"time"
+)
+
+type Repo struct {
+	db *sql.DB
+}
+
+func NewRepo(db *sql.DB) *Repo {
+	return &Repo{db: db}
+}
+
+// Filter actions.
+const (
+	ActionOff     = "off"
+	ActionAlert   = "alert" // raid mode only: alert staff, touch nobody
+	ActionTimeout = "timeout"
+	ActionKick    = "kick"
+	ActionBan     = "ban"
+)
+
+// Anti-nuke limit keys.
+const (
+	LimitChannelDelete = "channel_delete"
+	LimitChannelCreate = "channel_create"
+	LimitRoleDelete    = "role_delete"
+	LimitRoleCreate    = "role_create"
+	LimitBan           = "ban"
+	LimitKick          = "kick"
+	LimitWebhookCreate = "webhook_create"
+)
+
+// DefaultLimits mirrors the column default in the migration.
+func DefaultLimits() map[string]int {
+	return map[string]int{
+		LimitChannelDelete: 2, LimitChannelCreate: 5, LimitRoleDelete: 2, LimitRoleCreate: 5,
+		LimitBan: 3, LimitKick: 5, LimitWebhookCreate: 3,
+	}
+}
+
+type Settings struct {
+	GuildID        int64
+	AlertChannelID int64
+	AlertRoleID    int64
+	AlertDM        bool
+
+	JoinGateEnabled       bool
+	NoAvatar              string
+	NewAccount            string
+	MinAccountAgeDays     int
+	AdvertisingName       string
+	UsernameFilter        string
+	UsernamePatterns      []string
+	UnverifiedBot         string
+	UnauthorizedBot       string
+	AntiRaidEnabled       bool
+	RaidJoinCount         int
+	RaidJoinSeconds       int
+	RaidAction            string
+	RaidPauseInvites      bool
+	RaidQuietMinutes      int
+	AntiNukeEnabled       bool
+	AntiNukeWindowSeconds int
+	AntiNukeLimits        map[string]int
+	AntiNukeLockServer    bool
+	QuarantineRoleID      int64
+	AntiNukeAutoRestore   bool
+	HeatEnabled           bool
+	HeatStrictness        string
+	HeatAction            string
+	HeatTimeoutMinutes    int
+	HeatEscalate          bool
+	HeatBlockedWords      []string
+	HeatPanicMembers      int
+	HeatLockdownMentions  int
+	JoinLock              string
+
+	// Configured is false when the guild has no row yet; the fields then
+	// hold the defaults, with every system off.
+	Configured bool
+}
+
+func Defaults(guildID int64) *Settings {
+	return &Settings{
+		GuildID:  guildID,
+		AlertDM:  true,
+		NoAvatar: ActionOff, NewAccount: ActionOff, MinAccountAgeDays: 7, AdvertisingName: ActionOff,
+		UsernameFilter: ActionOff, UnverifiedBot: ActionOff, UnauthorizedBot: ActionKick,
+		RaidJoinCount: 10, RaidJoinSeconds: 10, RaidAction: ActionKick, RaidPauseInvites: true, RaidQuietMinutes: 10,
+		AntiNukeWindowSeconds: 10, AntiNukeLimits: DefaultLimits(),
+		HeatStrictness: "medium", HeatAction: ActionTimeout, HeatTimeoutMinutes: 10, HeatEscalate: true, HeatPanicMembers: 3,
+		JoinLock: ActionOff,
+	}
+}
+
+func nullID(v int64) sql.NullInt64 { return sql.NullInt64{Int64: v, Valid: v != 0} }
+
+func (r *Repo) GetSettings(ctx context.Context, guildID int64) (*Settings, error) {
+	const q = `
+		SELECT alert_channel_id, alert_role_id, alert_dm,
+			joingate_enabled, joingate_no_avatar, joingate_new_account, joingate_min_account_age_days,
+			joingate_advertising_name, joingate_username_filter, to_json(joingate_username_patterns),
+			joingate_unverified_bot, joingate_unauthorized_bot,
+			antiraid_enabled, raid_join_count, raid_join_seconds, raid_action, raid_pause_invites, raid_quiet_minutes,
+			antinuke_enabled, antinuke_window_seconds, antinuke_limits, antinuke_lock_server, quarantine_role_id,
+			antinuke_auto_restore, heat_enabled, heat_strictness, heat_action, heat_timeout_minutes, heat_escalate,
+			to_json(heat_blocked_words), heat_panic_members, heat_lockdown_mentions,
+			join_lock
+		FROM security_settings WHERE guild_id = $1`
+	s := &Settings{GuildID: guildID, Configured: true}
+	var alertCh, alertRole, qRole sql.NullInt64
+	var patterns, words []byte
+	var limits []byte
+	err := r.db.QueryRowContext(ctx, q, guildID).Scan(
+		&alertCh, &alertRole, &s.AlertDM,
+		&s.JoinGateEnabled, &s.NoAvatar, &s.NewAccount, &s.MinAccountAgeDays,
+		&s.AdvertisingName, &s.UsernameFilter, &patterns,
+		&s.UnverifiedBot, &s.UnauthorizedBot,
+		&s.AntiRaidEnabled, &s.RaidJoinCount, &s.RaidJoinSeconds, &s.RaidAction, &s.RaidPauseInvites, &s.RaidQuietMinutes,
+		&s.AntiNukeEnabled, &s.AntiNukeWindowSeconds, &limits, &s.AntiNukeLockServer, &qRole,
+		&s.AntiNukeAutoRestore, &s.HeatEnabled, &s.HeatStrictness, &s.HeatAction, &s.HeatTimeoutMinutes, &s.HeatEscalate,
+		&words, &s.HeatPanicMembers, &s.HeatLockdownMentions,
+		&s.JoinLock,
+	)
+	if errors.Is(err, sql.ErrNoRows) {
+		return Defaults(guildID), nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	s.AlertChannelID, s.AlertRoleID, s.QuarantineRoleID = alertCh.Int64, alertRole.Int64, qRole.Int64
+	_ = json.Unmarshal(patterns, &s.UsernamePatterns)
+	_ = json.Unmarshal(words, &s.HeatBlockedWords)
+	s.AntiNukeLimits = DefaultLimits()
+	if len(limits) > 0 {
+		// Saved values override the defaults key by key, so a limit added
+		// in a later version still has a value for older rows.
+		var saved map[string]int
+		if err := json.Unmarshal(limits, &saved); err == nil {
+			for k, v := range saved {
+				s.AntiNukeLimits[k] = v
+			}
+		}
+	}
+	return s, nil
+}
+
+// ensureRow makes sure the guild has a settings row so single-column updates
+// below can be plain UPDATEs.
+func (r *Repo) ensureRow(ctx context.Context, guildID int64) error {
+	_, err := r.db.ExecContext(ctx, `INSERT INTO security_settings (guild_id) VALUES ($1) ON CONFLICT DO NOTHING`, guildID)
+	return err
+}
+
+func (r *Repo) update(ctx context.Context, guildID int64, set string, args ...any) error {
+	if err := r.ensureRow(ctx, guildID); err != nil {
+		return err
+	}
+	_, err := r.db.ExecContext(ctx, `UPDATE security_settings SET `+set+` WHERE guild_id = $1`, append([]any{guildID}, args...)...)
+	return err
+}
+
+// Feature names accepted by SetEnabled.
+const (
+	FeatureJoinGate = "joingate"
+	FeatureAntiRaid = "antiraid"
+	FeatureAntiNuke = "antinuke"
+	FeatureHeat     = "heat"
+)
+
+func (r *Repo) SetEnabled(ctx context.Context, guildID int64, feature string, on bool) error {
+	col := map[string]string{FeatureJoinGate: "joingate_enabled", FeatureAntiRaid: "antiraid_enabled", FeatureAntiNuke: "antinuke_enabled", FeatureHeat: "heat_enabled"}[feature]
+	if col == "" {
+		return errors.New("unknown feature " + feature)
+	}
+	return r.update(ctx, guildID, col+` = $2`, on)
+}
+
+func (r *Repo) SetAlerts(ctx context.Context, guildID, channelID, roleID int64) error {
+	return r.update(ctx, guildID, `alert_channel_id = $2, alert_role_id = $3`, nullID(channelID), nullID(roleID))
+}
+
+func (r *Repo) SetQuarantineRole(ctx context.Context, guildID, roleID int64) error {
+	return r.update(ctx, guildID, `quarantine_role_id = $2`, nullID(roleID))
+}
+
+func (r *Repo) SetJoinLock(ctx context.Context, guildID int64, mode string) error {
+	return r.update(ctx, guildID, `join_lock = $2`, mode)
+}
+
+// ---- Trusted ----
+
+type Trusted struct {
+	TargetID int64
+	Kind     string // "user" or "role"
+	AddedBy  int64
+}
+
+func (r *Repo) ListTrusted(ctx context.Context, guildID int64) ([]Trusted, error) {
+	rows, err := r.db.QueryContext(ctx, `SELECT target_id, kind, added_by FROM security_trusted WHERE guild_id = $1 ORDER BY created_at`, guildID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Trusted
+	for rows.Next() {
+		var t Trusted
+		if err := rows.Scan(&t.TargetID, &t.Kind, &t.AddedBy); err != nil {
+			return nil, err
+		}
+		out = append(out, t)
+	}
+	return out, rows.Err()
+}
+
+func (r *Repo) AddTrusted(ctx context.Context, guildID int64, t Trusted) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_trusted (guild_id, target_id, kind, added_by) VALUES ($1, $2, $3, $4)
+		ON CONFLICT (guild_id, target_id) DO UPDATE SET kind = EXCLUDED.kind`, guildID, t.TargetID, t.Kind, t.AddedBy)
+	return err
+}
+
+func (r *Repo) RemoveTrusted(ctx context.Context, guildID, targetID int64) (bool, error) {
+	res, err := r.db.ExecContext(ctx, `DELETE FROM security_trusted WHERE guild_id = $1 AND target_id = $2`, guildID, targetID)
+	if err != nil {
+		return false, err
+	}
+	n, err := res.RowsAffected()
+	return n > 0, err
+}
+
+// ---- Quarantine ----
+
+type Quarantine struct {
+	GuildID         int64
+	UserID          int64
+	PreviousRoleIDs []int64
+	Reason          string
+	CreatedAt       time.Time
+}
+
+// SaveQuarantine records a quarantine. If the member is already quarantined
+// the first record is kept, since its roles are the ones to give back.
+func (r *Repo) SaveQuarantine(ctx context.Context, q Quarantine) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_quarantines (guild_id, user_id, previous_role_ids, reason)
+		VALUES ($1, $2, COALESCE($3::bigint[], '{}'), $4)
+		ON CONFLICT (guild_id, user_id) DO NOTHING`, q.GuildID, q.UserID, q.PreviousRoleIDs, q.Reason)
+	return err
+}
+
+func scanQuarantine(row interface{ Scan(...any) error }) (Quarantine, error) {
+	var q Quarantine
+	var roles []byte
+	err := row.Scan(&q.GuildID, &q.UserID, &roles, &q.Reason, &q.CreatedAt)
+	if err == nil {
+		err = json.Unmarshal(roles, &q.PreviousRoleIDs)
+	}
+	return q, err
+}
+
+// GetQuarantine returns nil when the member isn't quarantined.
+func (r *Repo) GetQuarantine(ctx context.Context, guildID, userID int64) (*Quarantine, error) {
+	q, err := scanQuarantine(r.db.QueryRowContext(ctx, `
+		SELECT guild_id, user_id, to_json(previous_role_ids), reason, created_at FROM security_quarantines
+		WHERE guild_id = $1 AND user_id = $2`, guildID, userID))
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &q, nil
+}
+
+func (r *Repo) ListQuarantines(ctx context.Context, guildID int64) ([]Quarantine, error) {
+	rows, err := r.db.QueryContext(ctx, `
+		SELECT guild_id, user_id, to_json(previous_role_ids), reason, created_at FROM security_quarantines
+		WHERE guild_id = $1 ORDER BY created_at DESC`, guildID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Quarantine
+	for rows.Next() {
+		q, err := scanQuarantine(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, q)
+	}
+	return out, rows.Err()
+}
+
+func (r *Repo) DeleteQuarantine(ctx context.Context, guildID, userID int64) error {
+	_, err := r.db.ExecContext(ctx, `DELETE FROM security_quarantines WHERE guild_id = $1 AND user_id = $2`, guildID, userID)
+	return err
+}
+
+// ---- Lockdowns ----
+
+type Lockdown struct {
+	GuildID       int64
+	ChannelID     int64
+	HadOverwrite  bool
+	PreviousAllow int64
+	PreviousDeny  int64
+	ServerWide    bool
+	LockedBy      int64
+}
+
+// SaveLockdown remembers a channel's @everyone overwrite from before it was
+// locked. A channel that is already locked keeps its first record, which is
+// the state to go back to.
+func (r *Repo) SaveLockdown(ctx context.Context, l Lockdown) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_lockdowns (guild_id, channel_id, had_overwrite, previous_allow, previous_deny, server_wide, locked_by)
+		VALUES ($1, $2, $3, $4, $5, $6, $7)
+		ON CONFLICT (guild_id, channel_id) DO NOTHING`,
+		l.GuildID, l.ChannelID, l.HadOverwrite, l.PreviousAllow, l.PreviousDeny, l.ServerWide, l.LockedBy)
+	return err
+}
+
+// GetLockdown returns nil when the channel isn't locked by the bot.
+func (r *Repo) GetLockdown(ctx context.Context, guildID, channelID int64) (*Lockdown, error) {
+	var l Lockdown
+	err := r.db.QueryRowContext(ctx, `
+		SELECT guild_id, channel_id, had_overwrite, previous_allow, previous_deny, server_wide, locked_by
+		FROM security_lockdowns WHERE guild_id = $1 AND channel_id = $2`, guildID, channelID).
+		Scan(&l.GuildID, &l.ChannelID, &l.HadOverwrite, &l.PreviousAllow, &l.PreviousDeny, &l.ServerWide, &l.LockedBy)
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &l, nil
+}
+
+// ListLockdowns lists locked channels; serverWideOnly limits it to the ones a
+// server lockdown locked.
+func (r *Repo) ListLockdowns(ctx context.Context, guildID int64, serverWideOnly bool) ([]Lockdown, error) {
+	rows, err := r.db.QueryContext(ctx, `
+		SELECT guild_id, channel_id, had_overwrite, previous_allow, previous_deny, server_wide, locked_by
+		FROM security_lockdowns WHERE guild_id = $1 AND (NOT $2 OR server_wide) ORDER BY locked_at`, guildID, serverWideOnly)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Lockdown
+	for rows.Next() {
+		var l Lockdown
+		if err := rows.Scan(&l.GuildID, &l.ChannelID, &l.HadOverwrite, &l.PreviousAllow, &l.PreviousDeny, &l.ServerWide, &l.LockedBy); err != nil {
+			return nil, err
+		}
+		out = append(out, l)
+	}
+	return out, rows.Err()
+}
+
+func (r *Repo) DeleteLockdown(ctx context.Context, guildID, channelID int64) error {
+	_, err := r.db.ExecContext(ctx, `DELETE FROM security_lockdowns WHERE guild_id = $1 AND channel_id = $2`, guildID, channelID)
+	return err
+}
+
+// ---- Events ----
+
+type Event struct {
+	GuildID  int64
+	Kind     string
+	ActorID  int64
+	TargetID int64
+	Detail   string
+}
+
+// Event kinds.
+const (
+	EventJoinGate        = "joingate"
+	EventRaidStarted     = "raid_started"
+	EventRaidEnded       = "raid_ended"
+	EventNuke            = "nuke"
+	EventQuarantined     = "quarantined"
+	EventReleased        = "released"
+	EventUnauthorizedBot = "unauthorized_bot"
+	EventLocked          = "locked"
+	EventUnlocked        = "unlocked"
+	EventHeat            = "heat"
+	EventHeatPanic       = "heat_panic"
+	EventSnapshot        = "snapshot"
+	EventRestored        = "restored"
+)
+
+func (r *Repo) AddEvent(ctx context.Context, e Event) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_events (guild_id, kind, actor_id, target_id, detail) VALUES ($1, $2, $3, $4, $5)`,
+		e.GuildID, e.Kind, nullID(e.ActorID), nullID(e.TargetID), e.Detail)
+	return err
+}
+
+// ---- Dashboard commands ----
+
+type Command struct {
+	ID          int64
+	GuildID     int64
+	CommandType string
+	Payload     []byte
+	RequestedBy int64
+}
+
+func (r *Repo) ListUnprocessedCommands(ctx context.Context) ([]Command, error) {
+	rows, err := r.db.QueryContext(ctx, `
+		SELECT id, guild_id, command_type, COALESCE(payload, '{}'::jsonb), requested_by
+		FROM security_commands WHERE processed_at IS NULL ORDER BY id`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Command
+	for rows.Next() {
+		var c Command
+		if err := rows.Scan(&c.ID, &c.GuildID, &c.CommandType, &c.Payload, &c.RequestedBy); err != nil {
+			return nil, err
+		}
+		out = append(out, c)
+	}
+	return out, rows.Err()
+}
+
+func (r *Repo) MarkCommandProcessed(ctx context.Context, id int64) error {
+	_, err := r.db.ExecContext(ctx, `UPDATE security_commands SET processed_at = NOW() WHERE id = $1`, id)
+	return err
+}
+
+// ---- Raids in progress ----
+
+type Raid struct {
+	GuildID       int64
+	StartedAt     time.Time
+	LastJoinAt    time.Time
+	InvitesPaused bool
+	CaughtTotal   int
+}
+
+func (r *Repo) SaveRaid(ctx context.Context, x Raid) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_raids (guild_id, started_at, last_join_at, invites_paused, caught_total)
+		VALUES ($1, $2, $3, $4, $5)
+		ON CONFLICT (guild_id) DO UPDATE SET
+			last_join_at = EXCLUDED.last_join_at, invites_paused = EXCLUDED.invites_paused, caught_total = EXCLUDED.caught_total`,
+		x.GuildID, x.StartedAt, x.LastJoinAt, x.InvitesPaused, x.CaughtTotal)
+	return err
+}
+
+func (r *Repo) ListRaids(ctx context.Context) ([]Raid, error) {
+	rows, err := r.db.QueryContext(ctx, `SELECT guild_id, started_at, last_join_at, invites_paused, caught_total FROM security_raids`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Raid
+	for rows.Next() {
+		var x Raid
+		if err := rows.Scan(&x.GuildID, &x.StartedAt, &x.LastJoinAt, &x.InvitesPaused, &x.CaughtTotal); err != nil {
+			return nil, err
+		}
+		out = append(out, x)
+	}
+	return out, rows.Err()
+}
+
+// DeleteRaid ends a raid's record and its caught list.
+func (r *Repo) DeleteRaid(ctx context.Context, guildID int64) error {
+	if _, err := r.db.ExecContext(ctx, `DELETE FROM security_raid_caught WHERE guild_id = $1`, guildID); err != nil {
+		return err
+	}
+	_, err := r.db.ExecContext(ctx, `DELETE FROM security_raids WHERE guild_id = $1`, guildID)
+	return err
+}
+
+type Caught struct {
+	UserID int64
+	Action string
+	Name   string
+}
+
+func (r *Repo) AddRaidCaught(ctx context.Context, guildID int64, c Caught) error {
+	_, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_raid_caught (guild_id, user_id, action, name) VALUES ($1, $2, $3, $4)
+		ON CONFLICT (guild_id, user_id) DO NOTHING`, guildID, c.UserID, c.Action, c.Name)
+	return err
+}
+
+func (r *Repo) ListRaidCaught(ctx context.Context, guildID int64, limit int) ([]Caught, error) {
+	rows, err := r.db.QueryContext(ctx, `
+		SELECT user_id, action, name FROM security_raid_caught WHERE guild_id = $1 ORDER BY caught_at LIMIT $2`, guildID, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Caught
+	for rows.Next() {
+		var c Caught
+		if err := rows.Scan(&c.UserID, &c.Action, &c.Name); err != nil {
+			return nil, err
+		}
+		out = append(out, c)
+	}
+	return out, rows.Err()
+}
+
+// ---- Snapshots ----
+
+const keepSnapshots = 3
+
+type Snapshot struct {
+	ID        int64
+	GuildID   int64
+	Data      []byte
+	Roles     int
+	Channels  int
+	CreatedAt time.Time
+}
+
+// SaveSnapshot stores a snapshot and drops all but the newest three.
+func (r *Repo) SaveSnapshot(ctx context.Context, s Snapshot) error {
+	if _, err := r.db.ExecContext(ctx, `
+		INSERT INTO security_snapshots (guild_id, data, roles, channels) VALUES ($1, $2, $3, $4)`,
+		s.GuildID, s.Data, s.Roles, s.Channels); err != nil {
+		return err
+	}
+	_, err := r.db.ExecContext(ctx, `
+		DELETE FROM security_snapshots WHERE guild_id = $1 AND id NOT IN (
+			SELECT id FROM security_snapshots WHERE guild_id = $1 ORDER BY created_at DESC, id DESC LIMIT $2)`,
+		s.GuildID, keepSnapshots)
+	return err
+}
+
+// LatestSnapshot returns nil when the guild has none.
+func (r *Repo) LatestSnapshot(ctx context.Context, guildID int64) (*Snapshot, error) {
+	var s Snapshot
+	err := r.db.QueryRowContext(ctx, `
+		SELECT id, guild_id, data, roles, channels, created_at FROM security_snapshots
+		WHERE guild_id = $1 ORDER BY created_at DESC, id DESC LIMIT 1`, guildID).
+		Scan(&s.ID, &s.GuildID, &s.Data, &s.Roles, &s.Channels, &s.CreatedAt)
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &s, nil
+}
+
+// GuildsDueForSnapshot lists guilds with anti-nuke on whose newest snapshot
+// is older than maxAge (or that have none).
+func (r *Repo) GuildsDueForSnapshot(ctx context.Context, maxAge time.Duration) ([]int64, error) {
+	rows, err := r.db.QueryContext(ctx, `
+		SELECT s.guild_id FROM security_settings s
+		WHERE s.antinuke_enabled AND NOT EXISTS (
+			SELECT 1 FROM security_snapshots p WHERE p.guild_id = s.guild_id AND p.created_at > NOW() - make_interval(secs => $1))`,
+		maxAge.Seconds())
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []int64
+	for rows.Next() {
+		var g int64
+		if err := rows.Scan(&g); err != nil {
+			return nil, err
+		}
+		out = append(out, g)
+	}
+	return out, rows.Err()
+}

internal/db/repos/securityrepo/repo_integration_test.go

@@ -0,0 +1,231 @@
+//go:build integration
+
+// Runs against a real Postgres with the dashboard API's migrations applied:
+//
+//	SECURITY_TEST_DB=postgres://... go test -tags integration ./internal/db/repos/securityrepo
+package securityrepo
+
+import (
+	"context"
+	"database/sql"
+	"os"
+	"testing"
+	"time"
+
+	_ "github.com/jackc/pgx/v5/stdlib"
+)
+
+func testRepo(t *testing.T) (*Repo, int64) {
+	t.Helper()
+	dsn := os.Getenv("SECURITY_TEST_DB")
+	if dsn == "" {
+		t.Skip("SECURITY_TEST_DB not set")
+	}
+	db, err := sql.Open("pgx", dsn)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { db.Close() })
+	const g = 777
+	for _, tbl := range []string{"security_settings", "security_trusted", "security_quarantines", "security_lockdowns", "security_events", "security_commands"} {
+		if _, err := db.Exec(`DELETE FROM `+tbl+` WHERE guild_id = $1`, g); err != nil {
+			t.Fatal(err)
+		}
+	}
+	return NewRepo(db), g
+}
+
+func TestSettings(t *testing.T) {
+	r, g := testRepo(t)
+	ctx := context.Background()
+
+	s, err := r.GetSettings(ctx, g)
+	if err != nil || s.Configured || s.JoinGateEnabled || s.AntiNukeEnabled || s.UnauthorizedBot != ActionKick || s.AntiNukeLimits[LimitChannelDelete] != 2 || !s.AlertDM {
+		t.Fatalf("defaults wrong: %+v %v", s, err)
+	}
+	for _, f := range []string{FeatureJoinGate, FeatureAntiRaid, FeatureAntiNuke} {
+		if err := r.SetEnabled(ctx, g, f, true); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := r.SetEnabled(ctx, g, "drop table", true); err == nil {
+		t.Error("unknown features must be refused, never put into SQL")
+	}
+	_ = r.SetAlerts(ctx, g, 10, 20)
+	if _, err := r.db.Exec(`UPDATE security_settings SET alert_dm = false WHERE guild_id = $1`, g); err != nil {
+		t.Fatal(err)
+	}
+	_ = r.SetQuarantineRole(ctx, g, 30)
+	_ = r.SetJoinLock(ctx, g, ActionBan)
+	if _, err := r.db.Exec(`UPDATE security_settings SET joingate_username_patterns = '{nitro,free}', antinuke_limits = '{"ban": 0}' WHERE guild_id = $1`, g); err != nil {
+		t.Fatal(err)
+	}
+
+	s, err = r.GetSettings(ctx, g)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !s.Configured || s.AlertDM || !s.JoinGateEnabled || !s.AntiRaidEnabled || !s.AntiNukeEnabled || s.AlertChannelID != 10 || s.AlertRoleID != 20 || s.QuarantineRoleID != 30 || s.JoinLock != ActionBan {
+		t.Errorf("saved settings wrong: %+v", s)
+	}
+	if len(s.UsernamePatterns) != 2 || s.AntiNukeLimits[LimitBan] != 0 || s.AntiNukeLimits[LimitKick] != 5 {
+		t.Errorf("patterns or limits wrong (saved limits override defaults key by key): %+v %+v", s.UsernamePatterns, s.AntiNukeLimits)
+	}
+	if err := r.SetJoinLock(ctx, g, "everyone"); err == nil {
+		t.Error("the database must refuse unknown join lock modes")
+	}
+}
+
+func TestTrustedQuarantineLockdown(t *testing.T) {
+	r, g := testRepo(t)
+	ctx := context.Background()
+
+	_ = r.AddTrusted(ctx, g, Trusted{TargetID: 5, Kind: "user", AddedBy: 1})
+	_ = r.AddTrusted(ctx, g, Trusted{TargetID: 6, Kind: "role", AddedBy: 1})
+	if err := r.AddTrusted(ctx, g, Trusted{TargetID: 7, Kind: "everyone", AddedBy: 1}); err == nil {
+		t.Error("unknown kinds must be refused")
+	}
+	list, _ := r.ListTrusted(ctx, g)
+	if len(list) != 2 {
+		t.Fatalf("trusted = %+v", list)
+	}
+	if ok, _ := r.RemoveTrusted(ctx, g, 5); !ok {
+		t.Error("remove should report true")
+	}
+
+	_ = r.SaveQuarantine(ctx, Quarantine{GuildID: g, UserID: 9, PreviousRoleIDs: []int64{1, 2}, Reason: "first"})
+	_ = r.SaveQuarantine(ctx, Quarantine{GuildID: g, UserID: 9, PreviousRoleIDs: nil, Reason: "second"})
+	q, _ := r.GetQuarantine(ctx, g, 9)
+	if q == nil || len(q.PreviousRoleIDs) != 2 || q.Reason != "first" {
+		t.Errorf("the first quarantine record must be kept: %+v", q)
+	}
+	qs, _ := r.ListQuarantines(ctx, g)
+	if len(qs) != 1 {
+		t.Errorf("list = %+v", qs)
+	}
+	_ = r.DeleteQuarantine(ctx, g, 9)
+	if q, _ := r.GetQuarantine(ctx, g, 9); q != nil {
+		t.Error("deleted")
+	}
+
+	_ = r.SaveLockdown(ctx, Lockdown{GuildID: g, ChannelID: 50, HadOverwrite: true, PreviousAllow: 1, PreviousDeny: 2, ServerWide: true, LockedBy: 1})
+	_ = r.SaveLockdown(ctx, Lockdown{GuildID: g, ChannelID: 50, HadOverwrite: false, PreviousAllow: 9, PreviousDeny: 9, LockedBy: 2})
+	_ = r.SaveLockdown(ctx, Lockdown{GuildID: g, ChannelID: 51, LockedBy: 1})
+	l, _ := r.GetLockdown(ctx, g, 50)
+	if l == nil || !l.HadOverwrite || l.PreviousAllow != 1 || !l.ServerWide {
+		t.Errorf("the first lockdown record must be kept: %+v", l)
+	}
+	if all, _ := r.ListLockdowns(ctx, g, false); len(all) != 2 {
+		t.Errorf("all = %+v", all)
+	}
+	if server, _ := r.ListLockdowns(ctx, g, true); len(server) != 1 {
+		t.Errorf("server-wide = %+v", server)
+	}
+	_ = r.DeleteLockdown(ctx, g, 50)
+	if l, _ := r.GetLockdown(ctx, g, 50); l != nil {
+		t.Error("deleted")
+	}
+
+	if err := r.AddEvent(ctx, Event{GuildID: g, Kind: EventNuke, ActorID: 3, Detail: "x"}); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := r.db.Exec(`INSERT INTO security_commands (guild_id, command_type, payload, requested_by) VALUES ($1, 'release_quarantine', '{"user_id":"9"}', 1)`, g); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := r.db.Exec(`INSERT INTO security_commands (guild_id, command_type, requested_by) VALUES ($1, 'grant_admin', 1)`, g); err == nil {
+		t.Error("unknown commands must be refused")
+	}
+	cmds, _ := r.ListUnprocessedCommands(ctx)
+	var mine *Command
+	for i := range cmds {
+		if cmds[i].GuildID == g {
+			mine = &cmds[i]
+		}
+	}
+	if mine == nil || string(mine.Payload) != `{"user_id": "9"}` {
+		t.Fatalf("command = %+v", mine)
+	}
+	_ = r.MarkCommandProcessed(ctx, mine.ID)
+}
+
+func TestRaidsSnapshotsAndHeatSettings(t *testing.T) {
+	r, g := testRepo(t)
+	ctx := context.Background()
+	if _, err := r.db.Exec(`DELETE FROM security_raids WHERE guild_id = $1`, g); err != nil {
+		t.Fatal(err)
+	}
+	_, _ = r.db.Exec(`DELETE FROM security_raid_caught WHERE guild_id = $1`, g)
+	_, _ = r.db.Exec(`DELETE FROM security_snapshots WHERE guild_id = $1`, g)
+
+	s, _ := r.GetSettings(ctx, g)
+	if s.HeatEnabled || s.HeatStrictness != "medium" || s.HeatTimeoutMinutes != 10 || !s.HeatEscalate || s.HeatPanicMembers != 3 {
+		t.Errorf("heat defaults wrong: %+v", s)
+	}
+	_ = r.SetEnabled(ctx, g, FeatureHeat, true)
+	if _, err := r.db.Exec(`UPDATE security_settings SET heat_blocked_words = '{scam}', antinuke_auto_restore = true WHERE guild_id = $1`, g); err != nil {
+		t.Fatal(err)
+	}
+	s, _ = r.GetSettings(ctx, g)
+	if !s.HeatEnabled || !s.AntiNukeAutoRestore || len(s.HeatBlockedWords) != 1 {
+		t.Errorf("heat settings not read back: %+v", s)
+	}
+	if _, err := r.db.Exec(`UPDATE security_settings SET heat_strictness = 'insane' WHERE guild_id = $1`, g); err == nil {
+		t.Error("unknown strictness must be refused by the database")
+	}
+
+	start := time.Now().Add(-time.Minute).UTC().Truncate(time.Millisecond)
+	_ = r.SaveRaid(ctx, Raid{GuildID: g, StartedAt: start, LastJoinAt: start, InvitesPaused: true, CaughtTotal: 1})
+	_ = r.SaveRaid(ctx, Raid{GuildID: g, StartedAt: time.Now(), LastJoinAt: start.Add(time.Second), InvitesPaused: true, CaughtTotal: 2})
+	_ = r.AddRaidCaught(ctx, g, Caught{UserID: 1, Action: "kick", Name: "a"})
+	_ = r.AddRaidCaught(ctx, g, Caught{UserID: 1, Action: "ban", Name: "a"})
+	_ = r.AddRaidCaught(ctx, g, Caught{UserID: 2, Action: "kick", Name: "b"})
+	raids, _ := r.ListRaids(ctx)
+	var mine *Raid
+	for i := range raids {
+		if raids[i].GuildID == g {
+			mine = &raids[i]
+		}
+	}
+	if mine == nil || !mine.StartedAt.Equal(start) || mine.CaughtTotal != 2 {
+		t.Fatalf("raid = %+v (the start time is kept on update)", mine)
+	}
+	caught, _ := r.ListRaidCaught(ctx, g, 10)
+	if len(caught) != 2 || caught[0].Action != "kick" {
+		t.Errorf("caught = %+v (one row per raider)", caught)
+	}
+	_ = r.DeleteRaid(ctx, g)
+	if c, _ := r.ListRaidCaught(ctx, g, 10); len(c) != 0 {
+		t.Error("deleting a raid clears its list")
+	}
+
+	for i := 0; i < 5; i++ {
+		if err := r.SaveSnapshot(ctx, Snapshot{GuildID: g, Data: []byte(`{"roles":[],"channels":[]}`), Roles: i}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	var n int
+	_ = r.db.QueryRow(`SELECT COUNT(*) FROM security_snapshots WHERE guild_id = $1`, g).Scan(&n)
+	if n != 3 {
+		t.Errorf("only the last three snapshots are kept, have %d", n)
+	}
+	latest, _ := r.LatestSnapshot(ctx, g)
+	if latest == nil || latest.Roles != 4 {
+		t.Errorf("latest = %+v", latest)
+	}
+	_ = r.SetEnabled(ctx, g, FeatureAntiNuke, true)
+	due, _ := r.GuildsDueForSnapshot(ctx, time.Hour)
+	for _, d := range due {
+		if d == g {
+			t.Error("a guild with a fresh snapshot is not due")
+		}
+	}
+	due, _ = r.GuildsDueForSnapshot(ctx, 0)
+	found := false
+	for _, d := range due {
+		found = found || d == g
+	}
+	if !found {
+		t.Error("with a zero max age every anti-nuke guild is due")
+	}
+}

internal/security/alerts.go

@@ -0,0 +1,144 @@
+package security
+
+import (
+	"bytes"
+	"context"
+	"log"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+const (
+	colorAlert = 0xdc2626
+	colorWarn  = 0xf59e0b
+	colorOK    = 0x16a34a
+)
+
+type alert struct {
+	embed     *discordgo.MessageEmbed
+	ping      bool // ping the alert role (raids and nukes, not routine join gate actions)
+	pingOwner bool
+	// critical alerts also go by DM to the owner and trusted users, since
+	// the alert channel may be gone or locked in exactly these moments.
+	critical   bool
+	components []discordgo.MessageComponent
+	file       *discordgo.File
+}
+
+// send posts an alert to the configured channel. It only ever pings the
+// configured alert role (never @everyone, even if that was saved somehow) and
+// optionally the owner.
+func (e *Engine) send(ctx context.Context, guildID string, s *securityrepo.Settings, a alert) *discordgo.Message {
+	if a.critical && s.AlertDM {
+		if e.syncDMs {
+			e.dmAlert(ctx, guildID, s, a)
+		} else {
+			go e.dmAlert(context.Background(), guildID, s, a)
+		}
+	}
+	if s.AlertChannelID == 0 {
+		return nil
+	}
+	msg := &discordgo.MessageSend{
+		Embeds:          []*discordgo.MessageEmbed{a.embed},
+		Components:      a.components,
+		AllowedMentions: &discordgo.MessageAllowedMentions{},
+	}
+	if a.ping && s.AlertRoleID != 0 && id(s.AlertRoleID) != guildID {
+		msg.Content = "<@&" + id(s.AlertRoleID) + ">"
+		msg.AllowedMentions.Roles = []string{id(s.AlertRoleID)}
+	}
+	if a.pingOwner {
+		if owner, err := e.OwnerID(guildID); err == nil && owner != "" {
+			msg.Content += " <@" + owner + ">"
+			msg.AllowedMentions.Users = []string{owner}
+		}
+	}
+	if a.file != nil {
+		msg.Files = []*discordgo.File{a.file}
+	}
+	m, err := e.d.ChannelMessageSendComplex(id(s.AlertChannelID), msg)
+	if err != nil {
+		log.Printf("security: alert in guild %s: %v", guildID, err)
+		return nil
+	}
+	return m
+}
+
+func textFile(name, content string) *discordgo.File {
+	return &discordgo.File{Name: name, ContentType: "text/plain; charset=utf-8", Reader: bytes.NewReader([]byte(content))}
+}
+
+// maxAlertDMs caps how many people get each critical alert by DM. Mass DMs
+// from a bot look like spam to Discord.
+const maxAlertDMs = 10
+
+// alertDMRecipients is the owner plus trusted users (not roles, which could
+// hold many members), without duplicates or the bot itself.
+func (e *Engine) alertDMRecipients(ctx context.Context, guildID string) []string {
+	seen := map[string]bool{e.botID: true}
+	var out []string
+	add := func(u string) {
+		if u != "" && !seen[u] && len(out) < maxAlertDMs {
+			seen[u] = true
+			out = append(out, u)
+		}
+	}
+	if owner, err := e.OwnerID(guildID); err == nil {
+		add(owner)
+	}
+	if _, trusted, err := e.load(ctx, guildID); err == nil {
+		for _, t := range trusted {
+			if t.Kind == "user" {
+				add(id(t.TargetID))
+			}
+		}
+	}
+	return out
+}
+
+// dmAlert sends a critical alert to each recipient's DMs. Closed DMs and
+// other failures are skipped: the alert channel is still the main record.
+func (e *Engine) dmAlert(ctx context.Context, guildID string, s *securityrepo.Settings, a alert) {
+	if a.embed == nil {
+		return
+	}
+	server := e.guildName(guildID)
+	if server == "" {
+		server = "a server"
+	}
+	embed := *a.embed
+	embed.Footer = &discordgo.MessageEmbedFooter{Text: clip("Velox security · "+server, 200)}
+	extra := ""
+	if a.file != nil {
+		if s.AlertChannelID != 0 {
+			extra = "\nThe full list is posted in the alert channel."
+		} else {
+			extra = "\nSet an alert channel on the dashboard to also get the full list of accounts."
+		}
+	}
+	if extra != "" {
+		embed.Description = clip(embed.Description+extra, 4000)
+	}
+	msg := &discordgo.MessageSend{
+		Content:         "Security alert in **" + escapeText(server) + "**. Use the dashboard or `/security` in the server to act.",
+		Embeds:          []*discordgo.MessageEmbed{&embed},
+		AllowedMentions: &discordgo.MessageAllowedMentions{},
+	}
+	for _, u := range e.alertDMRecipients(ctx, guildID) {
+		ch, err := e.d.UserChannelCreate(u)
+		if err != nil {
+			continue
+		}
+		if _, err := e.d.ChannelMessageSendComplex(ch.ID, msg); err != nil {
+			log.Printf("security: DM alert to %s for guild %s: %v", u, guildID, err)
+		}
+	}
+}
+
+// escapeText defuses markdown and mentions in a name (e.g. a server name).
+func escapeText(s string) string {
+	return safeName(&discordgo.User{Username: s})
+}

internal/security/config.go

@@ -0,0 +1,207 @@
+package security
+
+import (
+	"context"
+	"fmt"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// The configuration calls below do their own permission checks, so every
+// way in (slash commands, buttons, anything added later) gets the same rules:
+//
+//   - switching a system on: Manage Server, or owner/trusted
+//   - switching a system off, alert and quarantine settings: owner/trusted
+//   - the trusted list: owner only
+//
+// actorPerms is the actor's permission set as Discord sent it with the
+// interaction.
+
+const maxTrusted = 25
+
+func hasManageGuild(perms int64) bool {
+	return perms&(discordgo.PermissionAdministrator|discordgo.PermissionManageGuild) != 0
+}
+
+// SetFeature turns the Join Gate, raid mode or anti-nuke on or off.
+func (e *Engine) SetFeature(ctx context.Context, guildID string, actor *discordgo.Member, actorPerms int64, feature string, on bool) error {
+	if actor == nil || actor.User == nil {
+		return ErrNotTrusted
+	}
+	switch feature {
+	case securityrepo.FeatureJoinGate, securityrepo.FeatureAntiRaid, securityrepo.FeatureAntiNuke, securityrepo.FeatureHeat:
+	default:
+		return UserError("Unknown feature.")
+	}
+	trustedErr := e.RequireTrusted(ctx, guildID, actor)
+	if !on && trustedErr != nil {
+		return trustedErr
+	}
+	if on && trustedErr != nil && !hasManageGuild(actorPerms) {
+		return UserError("You need Manage Server to turn security features on.")
+	}
+	if err := e.st.SetEnabled(ctx, parseID(guildID), feature, on); err != nil {
+		return err
+	}
+	e.Invalidate(guildID)
+	state := "off"
+	if on {
+		state = "on"
+	}
+	e.event(ctx, guildID, "settings", actor.User.ID, "", feature+" "+state)
+	return nil
+}
+
+func (e *Engine) roleByID(guildID, roleID string) (*discordgo.Role, []*discordgo.Role, error) {
+	roles, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return nil, nil, fmt.Errorf("listing roles: %w", err)
+	}
+	for _, r := range roles {
+		if r.ID == roleID {
+			return r, roles, nil
+		}
+	}
+	return nil, roles, UserError("That role isn't in this server.")
+}
+
+// SetAlerts sets where alerts go and which role they ping. Changing it could
+// hide alerts from the staff, so it needs owner or trusted.
+func (e *Engine) SetAlerts(ctx context.Context, guildID string, actor *discordgo.Member, channelID, roleID string) error {
+	if err := e.RequireTrusted(ctx, guildID, actor); err != nil {
+		return err
+	}
+	ch, err := e.d.Channel(channelID)
+	if err != nil || ch.GuildID != guildID {
+		return UserError("That channel isn't in this server.")
+	}
+	if ch.Type != discordgo.ChannelTypeGuildText && ch.Type != discordgo.ChannelTypeGuildNews {
+		return UserError("Alerts need a text channel.")
+	}
+	if roleID != "" {
+		if roleID == guildID {
+			return UserError("Alerts can't ping @everyone. Pick a staff role.")
+		}
+		if _, _, err := e.roleByID(guildID, roleID); err != nil {
+			return err
+		}
+	}
+	if err := e.st.SetAlerts(ctx, parseID(guildID), parseID(channelID), parseID(roleID)); err != nil {
+		return err
+	}
+	e.Invalidate(guildID)
+	e.event(ctx, guildID, "settings", actor.User.ID, channelID, "alerts channel and role changed")
+	return nil
+}
+
+// ValidateQuarantineRole checks a role can safely be the quarantine role:
+// in this server, not @everyone, not managed, no dangerous permissions, and
+// below Velox's highest role so the bot can assign it.
+func (e *Engine) ValidateQuarantineRole(guildID, roleID string) error {
+	if roleID == guildID {
+		return UserError("@everyone can't be the quarantine role.")
+	}
+	role, roles, err := e.roleByID(guildID, roleID)
+	if err != nil {
+		return err
+	}
+	if role.Managed {
+		return UserError("That role is managed by an integration and can't be assigned.")
+	}
+	if role.Permissions&DangerousPerms != 0 {
+		return UserError("The quarantine role can't have Administrator, Manage Server, Manage Roles or Manage Webhooks.")
+	}
+	me, err := e.d.GuildMember(guildID, e.botID)
+	if err != nil {
+		return fmt.Errorf("looking up Velox: %w", err)
+	}
+	top := -1
+	for _, r := range roles {
+		for _, mine := range me.Roles {
+			if r.ID == mine && r.Position > top {
+				top = r.Position
+			}
+		}
+	}
+	if role.Position >= top {
+		return UserError("That role is above Velox's highest role, so Velox couldn't assign it. Move it below Velox's role.")
+	}
+	return nil
+}
+
+// SetQuarantineRole sets (or with "" clears) the quarantine role.
+func (e *Engine) SetQuarantineRole(ctx context.Context, guildID string, actor *discordgo.Member, roleID string) error {
+	if err := e.RequireTrusted(ctx, guildID, actor); err != nil {
+		return err
+	}
+	if roleID != "" {
+		if err := e.ValidateQuarantineRole(guildID, roleID); err != nil {
+			return err
+		}
+	}
+	if err := e.st.SetQuarantineRole(ctx, parseID(guildID), parseID(roleID)); err != nil {
+		return err
+	}
+	e.Invalidate(guildID)
+	e.event(ctx, guildID, "settings", actor.User.ID, roleID, "quarantine role changed")
+	return nil
+}
+
+// Trust adds a user or role to the trusted list. Owner only: anyone trusted
+// can switch protection off, so trust must not spread on its own.
+func (e *Engine) Trust(ctx context.Context, guildID string, actor *discordgo.Member, kind, targetID string) error {
+	if actor == nil || actor.User == nil || !e.IsOwner(guildID, actor.User.ID) {
+		return ErrNotOwner
+	}
+	_, trusted, err := e.load(ctx, guildID)
+	if err != nil {
+		return err
+	}
+	if len(trusted) >= maxTrusted {
+		return UserError(fmt.Sprintf("The trusted list can hold at most %d entries.", maxTrusted))
+	}
+	switch kind {
+	case "role":
+		if targetID == guildID {
+			return UserError("Trusting @everyone would make everyone trusted.")
+		}
+		role, _, err := e.roleByID(guildID, targetID)
+		if err != nil {
+			return err
+		}
+		if role.Managed {
+			return UserError("Integration roles can't be trusted; trust the bot user instead.")
+		}
+	case "user":
+		if _, err := e.d.GuildMember(guildID, targetID); err != nil {
+			return UserError("That user isn't in this server.")
+		}
+	default:
+		return UserError("Trust a user or a role.")
+	}
+	if err := e.st.AddTrusted(ctx, parseID(guildID), securityrepo.Trusted{TargetID: parseID(targetID), Kind: kind, AddedBy: parseID(actor.User.ID)}); err != nil {
+		return err
+	}
+	e.Invalidate(guildID)
+	e.event(ctx, guildID, "trusted_added", actor.User.ID, targetID, kind)
+	return nil
+}
+
+// Untrust removes a user or role from the trusted list. Owner only.
+func (e *Engine) Untrust(ctx context.Context, guildID string, actor *discordgo.Member, targetID string) error {
+	if actor == nil || actor.User == nil || !e.IsOwner(guildID, actor.User.ID) {
+		return ErrNotOwner
+	}
+	ok, err := e.st.RemoveTrusted(ctx, parseID(guildID), parseID(targetID))
+	if err != nil {
+		return err
+	}
+	if !ok {
+		return UserError("That isn't on the trusted list.")
+	}
+	e.Invalidate(guildID)
+	e.event(ctx, guildID, "trusted_removed", actor.User.ID, targetID, "")
+	return nil
+}

internal/security/dm_test.go

@@ -0,0 +1,92 @@
+package security
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+func nuke(e *Engine) {
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+}
+
+func TestCriticalAlertsAreDMed(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	d.guildName = "Velox **HQ** @everyone"
+	// Owner (1) is also on the list as a user; a trusted role must not be expanded.
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 1, Kind: "user"}, {TargetID: 60, Kind: "user"}, {TargetID: 201, Kind: "role"}, {TargetID: 999, Kind: "user"}}
+	refresh(e)
+	nuke(e)
+
+	got := strings.Join(d.dmsTo(), ",")
+	if got != "1,60" {
+		t.Fatalf("DMs went to %q, want the owner and the trusted user once each (no role members, not the bot)", got)
+	}
+	var dm *discordgo.MessageSend
+	for i, ch := range d.sentTo {
+		if ch == "dm-1" {
+			dm = d.sent[i]
+		}
+	}
+	if !strings.Contains(dm.Embeds[0].Title, "Nuke attempt stopped") {
+		t.Errorf("DM should carry the alert: %+v", dm.Embeds[0])
+	}
+	if strings.Contains(dm.Content, "@everyone") || strings.Contains(dm.Content, "**HQ**") || dm.AllowedMentions == nil {
+		t.Errorf("the server name must be escaped and nothing pinged: %q", dm.Content)
+	}
+	if len(dm.Components) != 0 {
+		t.Error("no action buttons in DMs")
+	}
+}
+
+func TestDMsWorkWithoutAnAlertChannel(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.set(100).AlertChannelID = 0
+	refresh(e)
+	nuke(e)
+	if strings.Join(d.dmsTo(), ",") != "1" {
+		t.Errorf("the owner should still be told: %v", d.dmsTo())
+	}
+}
+
+func TestDMsCanBeTurnedOff(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.set(100).AlertDM = false
+	refresh(e)
+	nuke(e)
+	if len(d.dmsTo()) != 0 {
+		t.Errorf("DMs are off: %v", d.dmsTo())
+	}
+}
+
+func TestRoutineAlertsAreNotDMed(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.JoinGateEnabled, s.NoAvatar = true, securityrepo.ActionKick
+	refresh(e)
+	e.OnMemberJoin(ctx, guild, &discordgo.Member{User: &discordgo.User{ID: snowflakeAt(now.AddDate(-1, 0, 0), 1)}})
+	if len(d.dmsTo()) != 0 {
+		t.Error("Join Gate actions only go to the alert channel")
+	}
+}
+
+func TestClosedDMsAreSkippedAndListIsCapped(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	d.closedDMs = map[string]bool{"1": true}
+	for i := 0; i < 15; i++ {
+		st.trusted[100] = append(st.trusted[100], securityrepo.Trusted{TargetID: int64(700 + i), Kind: "user"})
+	}
+	refresh(e)
+	nuke(e)
+	got := d.dmsTo()
+	if len(got) != maxAlertDMs-1 {
+		t.Errorf("owner's DMs are closed and the list is capped at %d: got %d (%v)", maxAlertDMs, len(got), got)
+	}
+	if got[0] != fmt.Sprint(700) {
+		t.Errorf("the others still get it: %v", got)
+	}
+}

internal/security/fakes_test.go

@@ -0,0 +1,557 @@
+package security
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"sort"
+	"sync"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// fakeStore keeps everything in memory with the same rules as the SQL.
+type fakeStore struct {
+	mu          sync.Mutex
+	settings    map[int64]*securityrepo.Settings
+	trusted     map[int64][]securityrepo.Trusted
+	quarantines map[string]securityrepo.Quarantine
+	lockdowns   map[string]securityrepo.Lockdown
+	events      []securityrepo.Event
+	cmds        []securityrepo.Command
+	done        map[int64]bool
+	raids       map[int64]securityrepo.Raid
+	caught      map[int64][]securityrepo.Caught
+	snapshots   []securityrepo.Snapshot
+}
+
+func newStore() *fakeStore {
+	return &fakeStore{
+		settings: map[int64]*securityrepo.Settings{}, trusted: map[int64][]securityrepo.Trusted{},
+		quarantines: map[string]securityrepo.Quarantine{}, lockdowns: map[string]securityrepo.Lockdown{}, done: map[int64]bool{},
+		raids: map[int64]securityrepo.Raid{}, caught: map[int64][]securityrepo.Caught{},
+	}
+}
+
+func (f *fakeStore) SaveRaid(_ context.Context, x securityrepo.Raid) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if old, ok := f.raids[x.GuildID]; ok {
+		x.StartedAt = old.StartedAt
+	}
+	f.raids[x.GuildID] = x
+	return nil
+}
+func (f *fakeStore) ListRaids(context.Context) ([]securityrepo.Raid, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []securityrepo.Raid
+	for _, x := range f.raids {
+		out = append(out, x)
+	}
+	return out, nil
+}
+func (f *fakeStore) DeleteRaid(_ context.Context, g int64) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	delete(f.raids, g)
+	delete(f.caught, g)
+	return nil
+}
+func (f *fakeStore) AddRaidCaught(_ context.Context, g int64, c securityrepo.Caught) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	for _, x := range f.caught[g] {
+		if x.UserID == c.UserID {
+			return nil
+		}
+	}
+	f.caught[g] = append(f.caught[g], c)
+	return nil
+}
+func (f *fakeStore) ListRaidCaught(_ context.Context, g int64, limit int) ([]securityrepo.Caught, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	out := f.caught[g]
+	if len(out) > limit {
+		out = out[:limit]
+	}
+	return append([]securityrepo.Caught(nil), out...), nil
+}
+func (f *fakeStore) SaveSnapshot(_ context.Context, s securityrepo.Snapshot) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	s.ID = int64(len(f.snapshots) + 1)
+	s.CreatedAt = time.Date(2026, 10, 20, 6, 0, 0, 0, time.UTC)
+	f.snapshots = append(f.snapshots, s)
+	return nil
+}
+func (f *fakeStore) LatestSnapshot(_ context.Context, g int64) (*securityrepo.Snapshot, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	for i := len(f.snapshots) - 1; i >= 0; i-- {
+		if f.snapshots[i].GuildID == g {
+			s := f.snapshots[i]
+			return &s, nil
+		}
+	}
+	return nil, nil
+}
+func (f *fakeStore) GuildsDueForSnapshot(context.Context, time.Duration) ([]int64, error) {
+	return nil, nil
+}
+
+func key(a, b int64) string { return fmt.Sprint(a, "/", b) }
+
+func (f *fakeStore) set(g int64) *securityrepo.Settings {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	s, ok := f.settings[g]
+	if !ok {
+		s = securityrepo.Defaults(g)
+		s.Configured = true
+		f.settings[g] = s
+	}
+	return s
+}
+
+func (f *fakeStore) GetSettings(_ context.Context, g int64) (*securityrepo.Settings, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if s, ok := f.settings[g]; ok {
+		cp := *s
+		return &cp, nil
+	}
+	return securityrepo.Defaults(g), nil
+}
+func (f *fakeStore) SetEnabled(_ context.Context, g int64, feature string, on bool) error {
+	s := f.set(g)
+	switch feature {
+	case securityrepo.FeatureJoinGate:
+		s.JoinGateEnabled = on
+	case securityrepo.FeatureAntiRaid:
+		s.AntiRaidEnabled = on
+	case securityrepo.FeatureAntiNuke:
+		s.AntiNukeEnabled = on
+	}
+	return nil
+}
+func (f *fakeStore) SetAlerts(_ context.Context, g, ch, role int64) error {
+	s := f.set(g)
+	s.AlertChannelID, s.AlertRoleID = ch, role
+	return nil
+}
+func (f *fakeStore) SetQuarantineRole(_ context.Context, g, role int64) error {
+	f.set(g).QuarantineRoleID = role
+	return nil
+}
+func (f *fakeStore) SetJoinLock(_ context.Context, g int64, mode string) error {
+	f.set(g).JoinLock = mode
+	return nil
+}
+func (f *fakeStore) ListTrusted(_ context.Context, g int64) ([]securityrepo.Trusted, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return append([]securityrepo.Trusted(nil), f.trusted[g]...), nil
+}
+func (f *fakeStore) AddTrusted(_ context.Context, g int64, t securityrepo.Trusted) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.trusted[g] = append(f.trusted[g], t)
+	return nil
+}
+func (f *fakeStore) RemoveTrusted(_ context.Context, g, target int64) (bool, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var keep []securityrepo.Trusted
+	found := false
+	for _, t := range f.trusted[g] {
+		if t.TargetID == target {
+			found = true
+			continue
+		}
+		keep = append(keep, t)
+	}
+	f.trusted[g] = keep
+	return found, nil
+}
+func (f *fakeStore) SaveQuarantine(_ context.Context, q securityrepo.Quarantine) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if _, ok := f.quarantines[key(q.GuildID, q.UserID)]; !ok {
+		f.quarantines[key(q.GuildID, q.UserID)] = q
+	}
+	return nil
+}
+func (f *fakeStore) GetQuarantine(_ context.Context, g, u int64) (*securityrepo.Quarantine, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if q, ok := f.quarantines[key(g, u)]; ok {
+		return &q, nil
+	}
+	return nil, nil
+}
+func (f *fakeStore) ListQuarantines(_ context.Context, g int64) ([]securityrepo.Quarantine, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []securityrepo.Quarantine
+	for _, q := range f.quarantines {
+		if q.GuildID == g {
+			out = append(out, q)
+		}
+	}
+	return out, nil
+}
+func (f *fakeStore) DeleteQuarantine(_ context.Context, g, u int64) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	delete(f.quarantines, key(g, u))
+	return nil
+}
+func (f *fakeStore) SaveLockdown(_ context.Context, l securityrepo.Lockdown) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if _, ok := f.lockdowns[key(l.GuildID, l.ChannelID)]; !ok {
+		f.lockdowns[key(l.GuildID, l.ChannelID)] = l
+	}
+	return nil
+}
+func (f *fakeStore) GetLockdown(_ context.Context, g, ch int64) (*securityrepo.Lockdown, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if l, ok := f.lockdowns[key(g, ch)]; ok {
+		return &l, nil
+	}
+	return nil, nil
+}
+func (f *fakeStore) ListLockdowns(_ context.Context, g int64, serverOnly bool) ([]securityrepo.Lockdown, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []securityrepo.Lockdown
+	for _, l := range f.lockdowns {
+		if l.GuildID == g && (!serverOnly || l.ServerWide) {
+			out = append(out, l)
+		}
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].ChannelID < out[j].ChannelID })
+	return out, nil
+}
+func (f *fakeStore) DeleteLockdown(_ context.Context, g, ch int64) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	delete(f.lockdowns, key(g, ch))
+	return nil
+}
+func (f *fakeStore) AddEvent(_ context.Context, e securityrepo.Event) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.events = append(f.events, e)
+	return nil
+}
+func (f *fakeStore) eventKinds() []string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []string
+	for _, e := range f.events {
+		out = append(out, e.Kind)
+	}
+	return out
+}
+func (f *fakeStore) ListUnprocessedCommands(context.Context) ([]securityrepo.Command, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []securityrepo.Command
+	for _, c := range f.cmds {
+		if !f.done[c.ID] {
+			out = append(out, c)
+		}
+	}
+	return out, nil
+}
+func (f *fakeStore) MarkCommandProcessed(_ context.Context, id int64) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.done[id] = true
+	return nil
+}
+
+// fakeDiscord is a tiny in-memory guild.
+type fakeDiscord struct {
+	mu          sync.Mutex
+	ownerID     string
+	roles       []*discordgo.Role
+	members     map[string]*discordgo.Member
+	users       map[string]*discordgo.User
+	channels    map[string]*discordgo.Channel
+	kicked      []string
+	banned      []string
+	timeouts    map[string]*time.Time
+	sent        []*discordgo.MessageSend
+	sentTo      []string
+	files       map[string]string
+	requests    []string // "METHOD url body"
+	deletedMsgs []string
+	nextID      int
+	failEdits   error
+	rejectRole  string // edits that assign this role fail, like a role above Velox's
+	lookups     int    // member and role lookups, to check harmless entries cost nothing
+	closedDMs   map[string]bool
+	guildName   string
+}
+
+const guild = "100"
+
+func newDiscord() *fakeDiscord {
+	return &fakeDiscord{
+		ownerID: "1",
+		roles: []*discordgo.Role{
+			{ID: guild, Name: "@everyone", Position: 0},
+			{ID: "200", Name: "Admin", Position: 5, Permissions: discordgo.PermissionAdministrator},
+			{ID: "201", Name: "Mod", Position: 3, Permissions: discordgo.PermissionKickMembers},
+			{ID: "202", Name: "Member", Position: 1},
+			{ID: "203", Name: "Quarantine", Position: 2},
+			{ID: "204", Name: "Booster", Position: 1, Managed: true},
+			{ID: "299", Name: "Velox", Position: 9, Managed: true, Permissions: discordgo.PermissionAdministrator},
+		},
+		members: map[string]*discordgo.Member{
+			"1":   {User: &discordgo.User{ID: "1", Username: "owner"}},
+			"999": {User: &discordgo.User{ID: "999", Username: "velox", Bot: true}, Roles: []string{"299"}},
+		},
+		users:    map[string]*discordgo.User{},
+		channels: map[string]*discordgo.Channel{},
+		timeouts: map[string]*time.Time{},
+		files:    map[string]string{},
+	}
+}
+
+func (f *fakeDiscord) addMember(id string, roles ...string) *discordgo.Member {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	m := &discordgo.Member{User: &discordgo.User{ID: id, Username: "user" + id, Avatar: "a"}, Roles: roles}
+	f.members[id] = m
+	return m
+}
+
+func (f *fakeDiscord) Guild(g string, _ ...discordgo.RequestOption) (*discordgo.Guild, error) {
+	return &discordgo.Guild{ID: g, OwnerID: f.ownerID, Name: f.guildName}, nil
+}
+func (f *fakeDiscord) UserChannelCreate(u string, _ ...discordgo.RequestOption) (*discordgo.Channel, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.closedDMs[u] {
+		return nil, errors.New("Cannot send messages to this user")
+	}
+	return &discordgo.Channel{ID: "dm-" + u, Type: discordgo.ChannelTypeDM}, nil
+}
+
+// dmsTo lists who got a DM, in order.
+func (f *fakeDiscord) dmsTo() []string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []string
+	for _, ch := range f.sentTo {
+		if len(ch) > 3 && ch[:3] == "dm-" {
+			out = append(out, ch[3:])
+		}
+	}
+	return out
+}
+func (f *fakeDiscord) User(id string, _ ...discordgo.RequestOption) (*discordgo.User, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if u, ok := f.users[id]; ok {
+		return u, nil
+	}
+	return nil, errors.New("unknown user")
+}
+func (f *fakeDiscord) GuildRoles(string, ...discordgo.RequestOption) ([]*discordgo.Role, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.lookups++
+	return f.roles, nil
+}
+func (f *fakeDiscord) GuildChannels(g string, _ ...discordgo.RequestOption) ([]*discordgo.Channel, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []*discordgo.Channel
+	for _, c := range f.channels {
+		if c.GuildID == g {
+			out = append(out, c)
+		}
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].ID < out[j].ID })
+	return out, nil
+}
+func (f *fakeDiscord) GuildMember(_, u string, _ ...discordgo.RequestOption) (*discordgo.Member, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.lookups++
+	if m, ok := f.members[u]; ok {
+		cp := *m
+		cp.Roles = append([]string(nil), m.Roles...)
+		return &cp, nil
+	}
+	return nil, errors.New("unknown member")
+}
+func (f *fakeDiscord) GuildMemberEdit(_, u string, data *discordgo.GuildMemberParams, _ ...discordgo.RequestOption) (*discordgo.Member, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.failEdits != nil {
+		return nil, f.failEdits
+	}
+	if data.Roles != nil && f.rejectRole != "" {
+		for _, r := range *data.Roles {
+			if r == f.rejectRole {
+				return nil, errors.New("403 Missing Permissions")
+			}
+		}
+	}
+	m, ok := f.members[u]
+	if !ok {
+		return nil, errors.New("unknown member")
+	}
+	if data.Roles != nil {
+		m.Roles = append([]string(nil), (*data.Roles)...)
+	}
+	return m, nil
+}
+func (f *fakeDiscord) GuildMemberTimeout(_, u string, until *time.Time, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.timeouts[u] = until
+	return nil
+}
+func (f *fakeDiscord) GuildMemberDeleteWithReason(_, u, _ string, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.kicked = append(f.kicked, u)
+	delete(f.members, u)
+	return nil
+}
+func (f *fakeDiscord) GuildBanCreateWithReason(_, u, _ string, _ int, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.banned = append(f.banned, u)
+	delete(f.members, u)
+	return nil
+}
+func (f *fakeDiscord) Channel(id string, _ ...discordgo.RequestOption) (*discordgo.Channel, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if c, ok := f.channels[id]; ok {
+		cp := *c
+		cp.PermissionOverwrites = nil
+		for _, o := range c.PermissionOverwrites {
+			oc := *o
+			cp.PermissionOverwrites = append(cp.PermissionOverwrites, &oc)
+		}
+		return &cp, nil
+	}
+	return nil, errors.New("unknown channel")
+}
+func (f *fakeDiscord) ChannelPermissionSet(ch, target string, t discordgo.PermissionOverwriteType, allow, deny int64, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	c := f.channels[ch]
+	for _, o := range c.PermissionOverwrites {
+		if o.ID == target {
+			o.Allow, o.Deny = allow, deny
+			return nil
+		}
+	}
+	c.PermissionOverwrites = append(c.PermissionOverwrites, &discordgo.PermissionOverwrite{ID: target, Type: t, Allow: allow, Deny: deny})
+	return nil
+}
+func (f *fakeDiscord) ChannelPermissionDelete(ch, target string, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	c := f.channels[ch]
+	var keep []*discordgo.PermissionOverwrite
+	for _, o := range c.PermissionOverwrites {
+		if o.ID != target {
+			keep = append(keep, o)
+		}
+	}
+	c.PermissionOverwrites = keep
+	return nil
+}
+func (f *fakeDiscord) ChannelMessageSendComplex(ch string, data *discordgo.MessageSend, _ ...discordgo.RequestOption) (*discordgo.Message, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.sentTo = append(f.sentTo, ch)
+	for _, file := range data.Files {
+		raw, _ := io.ReadAll(file.Reader)
+		f.files[file.Name] = string(raw)
+	}
+	f.sent = append(f.sent, data)
+	return &discordgo.Message{ID: "m"}, nil
+}
+func (f *fakeDiscord) RequestWithBucketID(method, url string, data interface{}, _ string, _ ...discordgo.RequestOption) ([]byte, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.requests = append(f.requests, fmt.Sprintf("%s %s %v", method, url, data))
+	return nil, nil
+}
+
+// sentCount counts channel alerts (not DMs).
+func (f *fakeDiscord) sentCount() int {
+	return len(f.channelSends())
+}
+
+// channelSends lists messages sent to channels, leaving out DMs.
+func (f *fakeDiscord) channelSends() []*discordgo.MessageSend {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	var out []*discordgo.MessageSend
+	for i, m := range f.sent {
+		if i >= len(f.sentTo) || len(f.sentTo[i]) < 3 || f.sentTo[i][:3] != "dm-" {
+			out = append(out, m)
+		}
+	}
+	return out
+}
+
+func (f *fakeDiscord) newID() string {
+	f.nextID++
+	return fmt.Sprint(8000 + f.nextID)
+}
+func (f *fakeDiscord) ChannelMessageDelete(ch, msg string, _ ...discordgo.RequestOption) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.deletedMsgs = append(f.deletedMsgs, msg)
+	return nil
+}
+func (f *fakeDiscord) GuildRoleCreate(_ string, p *discordgo.RoleParams, _ ...discordgo.RequestOption) (*discordgo.Role, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	r := &discordgo.Role{ID: f.newID(), Name: p.Name}
+	if p.Permissions != nil {
+		r.Permissions = *p.Permissions
+	}
+	f.roles = append(f.roles, r)
+	return r, nil
+}
+func (f *fakeDiscord) GuildRoleEdit(_, roleID string, p *discordgo.RoleParams, _ ...discordgo.RequestOption) (*discordgo.Role, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	for _, r := range f.roles {
+		if r.ID == roleID {
+			if p.Permissions != nil {
+				r.Permissions = *p.Permissions
+			}
+			return r, nil
+		}
+	}
+	return nil, errors.New("unknown role")
+}
+func (f *fakeDiscord) GuildChannelCreateComplex(g string, d discordgo.GuildChannelCreateData, _ ...discordgo.RequestOption) (*discordgo.Channel, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	c := &discordgo.Channel{ID: f.newID(), GuildID: g, Name: d.Name, Type: d.Type, ParentID: d.ParentID, PermissionOverwrites: d.PermissionOverwrites}
+	f.channels[c.ID] = c
+	return c, nil
+}

internal/security/gaps_test.go

@@ -0,0 +1,328 @@
+package security
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// ---- Raid persistence ----
+
+func TestRaidSurvivesARestart(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.AntiRaidEnabled, s.RaidJoinCount, s.RaidAction, s.RaidQuietMinutes = true, 3, securityrepo.ActionKick, 5
+	refresh(e)
+	for i := 0; i < 4; i++ {
+		e.OnMemberJoin(ctx, guild, d.addMember(snowflakeAt(now.AddDate(-1, 0, 0), i)))
+	}
+	if r, ok := st.raids[100]; !ok || !r.InvitesPaused || r.CaughtTotal != 4 || len(st.caught[100]) != 4 {
+		t.Fatalf("raid not persisted: %+v caught=%d", st.raids[100], len(st.caught[100]))
+	}
+
+	// The bot restarts: a fresh engine on the same database.
+	e2 := New(d, st, "999")
+	e2.now = e.now
+	e2.ResumeRaids(ctx)
+	if !e2.RaidActive(guild) {
+		t.Fatal("raid mode must resume after a restart")
+	}
+	// A join after the restart is still treated as a raider.
+	*now = now.Add(time.Minute)
+	m := d.addMember(snowflakeAt(now.AddDate(-1, 0, 0), 50))
+	e2.OnMemberJoin(ctx, guild, m)
+	if !contains(d.kicked, m.User.ID) {
+		t.Error("raid actions continue after a restart")
+	}
+
+	// Quiet period: it ends, invites resume, the list covers both lifetimes.
+	*now = now.Add(6 * time.Minute)
+	e2.checkRaids(ctx)
+	if e2.RaidActive(guild) {
+		t.Fatal("the resumed raid should end after the quiet period")
+	}
+	if !strings.Contains(d.requests[len(d.requests)-1], "invites_disabled_until:<nil>") {
+		t.Error("invites paused before the restart must be resumed")
+	}
+	var list string
+	for name, content := range d.files {
+		if strings.HasPrefix(name, "raid-") {
+			list = content
+		}
+	}
+	if strings.Count(list, "\tkick\t") != 5 {
+		t.Errorf("summary should list all 5 raiders:\n%s", list)
+	}
+	if _, ok := st.raids[100]; ok {
+		t.Error("the raid record should be cleared")
+	}
+}
+
+// ---- Heat ----
+
+func heatEngine(t *testing.T) (*Engine, *fakeDiscord, *fakeStore, *time.Time) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.HeatEnabled, s.HeatPanicMembers = true, 0
+	refresh(e)
+	return e, d, st, now
+}
+
+var msgN int
+
+func say(e *Engine, userID, content string, edit ...func(m *discordgo.MessageCreate)) *discordgo.MessageCreate {
+	msgN++
+	m := &discordgo.MessageCreate{Message: &discordgo.Message{
+		ID: "msg" + string(rune('A'+msgN%26)) + strings.Repeat("x", msgN/26), GuildID: guild, ChannelID: "300", Content: content,
+		Author: &discordgo.User{ID: userID, Username: "u" + userID},
+		Member: &discordgo.Member{Roles: []string{}, JoinedAt: time.Date(2025, 1, 1, 0, 0, 0, 0, time.UTC)},
+	}}
+	for _, f := range edit {
+		f(m)
+	}
+	e.OnMessage(ctx, m)
+	return m
+}
+
+func TestNormalChatNeverHeatsUp(t *testing.T) {
+	e, d, _, now := heatEngine(t)
+	for i := 0; i < 60; i++ {
+		say(e, "50", "just talking about the game tonight, number "+string(rune('a'+i%26)))
+		*now = now.Add(2 * time.Second)
+	}
+	if len(d.deletedMsgs) != 0 || len(d.timeouts) != 0 {
+		t.Error("a message every two seconds is normal conversation")
+	}
+}
+
+func TestSpamIsPunishedAndEscalates(t *testing.T) {
+	e, d, st, now := heatEngine(t)
+	var last *discordgo.MessageCreate
+	for i := 0; i < 6 && d.timeouts["50"] == nil; i++ {
+		last = say(e, "50", "BUY CHEAP STUFF NOW")
+		*now = now.Add(200 * time.Millisecond)
+	}
+	first := d.timeouts["50"]
+	if first == nil || first.Sub(*now) > 11*time.Minute || first.Sub(*now) < 9*time.Minute {
+		t.Fatalf("repeated spam should earn the 10 minute timeout, got %v", first)
+	}
+	if !contains(d.deletedMsgs, last.ID) {
+		t.Error("the message that maxed the heat should be deleted")
+	}
+	if !contains(st.eventKinds(), securityrepo.EventHeat) {
+		t.Error("recorded")
+	}
+
+	// A second offence the same day doubles it.
+	*now = now.Add(time.Hour)
+	d.timeouts["50"] = nil
+	for i := 0; i < 6 && d.timeouts["50"] == nil; i++ {
+		say(e, "50", "BUY CHEAP STUFF NOW")
+		*now = now.Add(200 * time.Millisecond)
+	}
+	if second := d.timeouts["50"]; second == nil || second.Sub(*now) < 19*time.Minute {
+		t.Errorf("second offence should be 20 minutes, got %v", second)
+	}
+}
+
+func TestInviteLinksAndMassMentions(t *testing.T) {
+	e, d, _, _ := heatEngine(t)
+	say(e, "51", "join my server discord.gg/abcdef")
+	if d.timeouts["51"] == nil {
+		t.Error("an invite link is an instant max")
+	}
+	say(e, "52", "hey @everyone check this")
+	say(e, "52", "@everyone again")
+	if d.timeouts["52"] == nil {
+		t.Error("repeated @everyone should max out fast")
+	}
+}
+
+func TestHeatExemptions(t *testing.T) {
+	e, d, st, _ := heatEngine(t)
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 60, Kind: "user"}}
+	refresh(e)
+	e.ChannelPerms = func(userID, _ string) (int64, error) {
+		if userID == "61" {
+			return discordgo.PermissionManageMessages, nil
+		}
+		return 0, nil
+	}
+	for _, who := range []string{"1", "60", "61"} {
+		say(e, who, "discord.gg/x")
+	}
+	say(e, "62", "discord.gg/x", func(m *discordgo.MessageCreate) { m.Author.Bot = true })
+	say(e, "63", "discord.gg/x", func(m *discordgo.MessageCreate) { m.WebhookID = "w" })
+	if len(d.timeouts) != 0 || len(d.deletedMsgs) != 0 {
+		t.Errorf("owner, trusted, moderators, bots and webhooks are exempt: %v", d.timeouts)
+	}
+}
+
+func TestHeatPanicTimesOutNewMembers(t *testing.T) {
+	e, d, st, now := heatEngine(t)
+	st.set(100).HeatPanicMembers = 3
+	refresh(e)
+	for _, u := range []string{"70", "71", "72"} {
+		say(e, u, "discord.gg/spam")
+	}
+	if !contains(st.eventKinds(), securityrepo.EventHeatPanic) {
+		t.Fatal("three members maxing out within a minute starts heat panic")
+	}
+	newcomer := func(m *discordgo.MessageCreate) { m.Member.JoinedAt = now.Add(-time.Hour) }
+	say(e, "80", "hello everyone", newcomer)
+	if d.timeouts["80"] == nil {
+		t.Error("someone who joined an hour ago speaking during panic is timed out")
+	}
+	say(e, "81", "hello everyone")
+	if d.timeouts["81"] != nil {
+		t.Error("established members are unaffected by panic")
+	}
+	*now = now.Add(11 * time.Minute)
+	say(e, "82", "hello", newcomer)
+	if d.timeouts["82"] != nil {
+		t.Error("panic ends after 10 minutes")
+	}
+}
+
+func TestMentionFloodLocksTheServer(t *testing.T) {
+	e, d, st, _ := heatEngine(t)
+	s := st.set(100)
+	s.HeatLockdownMentions, s.HeatStrictness = 20, "low"
+	refresh(e)
+	d.channels["300"] = &discordgo.Channel{ID: "300", GuildID: guild, Type: discordgo.ChannelTypeGuildText}
+	five := func(m *discordgo.MessageCreate) {
+		m.Mentions = []*discordgo.User{{ID: "a"}, {ID: "b"}, {ID: "c"}, {ID: "d"}, {ID: "e"}}
+	}
+	for i, u := range []string{"90", "91", "92", "93"} {
+		_ = i
+		say(e, u, "hi", five)
+	}
+	deadline := time.Now().Add(2 * time.Second)
+	for time.Now().Before(deadline) {
+		st.mu.Lock()
+		n := len(st.lockdowns)
+		st.mu.Unlock()
+		if n > 0 {
+			return
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+	t.Error("20 mentions within 30 seconds should lock the server")
+}
+
+func TestHeatAlertsAreCapped(t *testing.T) {
+	e, d, _, _ := heatEngine(t)
+	for i := 0; i < 20; i++ {
+		say(e, string(rune('A'+i)), "discord.gg/x")
+	}
+	if n := d.sentCount(); n > heatAlertsPerMin {
+		t.Errorf("a spam wave produced %d alerts, cap is %d", n, heatAlertsPerMin)
+	}
+}
+
+// ---- Snapshots and restore ----
+
+func TestSnapshotAndRestore(t *testing.T) {
+	e, d, st, _ := testEngine(t)
+	d.channels["400"] = &discordgo.Channel{ID: "400", GuildID: guild, Type: discordgo.ChannelTypeGuildCategory, Name: "Staff"}
+	d.channels["401"] = &discordgo.Channel{ID: "401", GuildID: guild, Type: discordgo.ChannelTypeGuildText, Name: "mod-chat", ParentID: "400",
+		PermissionOverwrites: []*discordgo.PermissionOverwrite{
+			{ID: guild, Type: discordgo.PermissionOverwriteTypeRole, Deny: discordgo.PermissionViewChannel},
+			{ID: "201", Type: discordgo.PermissionOverwriteTypeRole, Allow: discordgo.PermissionViewChannel},
+		}}
+	d.channels["402"] = &discordgo.Channel{ID: "402", GuildID: guild, Type: discordgo.ChannelTypeGuildPublicThread, Name: "a thread"}
+
+	if _, err := e.Restore(ctx, guild, "1"); !errors.As(err, new(UserError)) {
+		t.Fatalf("no snapshot yet should be a clear message: %v", err)
+	}
+	roles, channels, err := e.TakeSnapshot(ctx, guild, "1")
+	if err != nil || roles != 5 || channels != 2 {
+		t.Fatalf("snapshot = %d roles, %d channels, %v (managed roles and threads are skipped)", roles, channels, err)
+	}
+	var data snapshotData
+	_ = json.Unmarshal(st.snapshots[0].Data, &data)
+	for _, r := range data.Roles {
+		if r.ID == "204" || r.ID == "299" {
+			t.Error("integration roles must not be in the snapshot")
+		}
+	}
+
+	// The nuke: the Mod role and the whole Staff category are deleted, and
+	// the Member role is given Administrator.
+	var keep []*discordgo.Role
+	for _, r := range d.roles {
+		if r.ID != "201" {
+			keep = append(keep, r)
+		}
+		if r.ID == "202" {
+			r.Permissions |= discordgo.PermissionAdministrator
+		}
+	}
+	d.roles = keep
+	delete(d.channels, "400")
+	delete(d.channels, "401")
+
+	res, err := e.Restore(ctx, guild, "1")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.RolesCreated != 1 || res.RolesReverted != 1 || res.ChannelsCreated != 2 || res.Failed != 0 {
+		t.Fatalf("restore result = %+v", res)
+	}
+	var newMod, newCat, newText *string
+	for _, r := range d.roles {
+		if r.Name == "Mod" {
+			newMod = &r.ID
+		}
+		if r.ID == "202" && r.Permissions&discordgo.PermissionAdministrator != 0 {
+			t.Error("Administrator added to Member should be reverted")
+		}
+	}
+	for _, c := range d.channels {
+		switch c.Name {
+		case "Staff":
+			newCat = &c.ID
+		case "mod-chat":
+			newText = &c.ID
+		}
+	}
+	if newMod == nil || newCat == nil || newText == nil {
+		t.Fatal("role or channels not recreated")
+	}
+	text := d.channels[*newText]
+	if text.ParentID != *newCat {
+		t.Error("the channel should go back into the recreated category")
+	}
+	foundMod := false
+	for _, o := range text.PermissionOverwrites {
+		if o.ID == *newMod && o.Allow == discordgo.PermissionViewChannel {
+			foundMod = true
+		}
+		if o.ID == "201" {
+			t.Error("overwrites must point at the recreated role, not the deleted one")
+		}
+	}
+	if !foundMod {
+		t.Errorf("the Mod overwrite should be restored: %+v", text.PermissionOverwrites)
+	}
+
+	// Restoring again finds nothing missing.
+	res, _ = e.Restore(ctx, guild, "1")
+	if res.RolesCreated+res.ChannelsCreated+res.RolesReverted != 0 {
+		t.Errorf("a second restore should change nothing: %+v", res)
+	}
+}
+
+func TestOnlyOneRestoreAtATime(t *testing.T) {
+	e, _, _, _ := testEngine(t)
+	e.restoring[guild] = true
+	if _, err := e.Restore(ctx, guild, "1"); err == nil || !strings.Contains(err.Error(), "already running") {
+		t.Errorf("err = %v", err)
+	}
+}

internal/security/heat.go

@@ -0,0 +1,368 @@
+package security
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"math"
+	"regexp"
+	"strings"
+	"sync"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Heat is a per-member spam score, like Wick's. Every message adds heat,
+// more for what spam looks like; heat cools down over time, so normal
+// conversation never builds up. At maxHeat the message is deleted and the
+// configured action applied.
+const (
+	maxHeat          = 100.0
+	heatDecayPerSec  = 8.0 // a message every couple of seconds never accumulates
+	heatBase         = 8.0
+	heatRepeat       = 25.0
+	heatMention      = 10.0
+	heatEveryone     = 60.0
+	heatEmoji        = 2.0
+	heatLine         = 2.0 // per line beyond the fourth
+	heatPer100Chars  = 1.0
+	heatAttachment   = 10.0
+	heatLink         = 8.0
+	heatBlockedWord  = 60.0
+	maxHeatUsers     = 50000 // per guild, swept when exceeded
+	panicWindow      = time.Minute
+	panicDuration    = 10 * time.Minute
+	panicTimeout     = time.Hour
+	panicNewMember   = 24 * time.Hour
+	mentionWindow    = 30 * time.Second
+	floodCooldown    = 10 * time.Minute
+	heatAlertsPerMin = 5
+	maxTimeout       = 28*24*time.Hour - time.Hour
+)
+
+var (
+	linkRe        = regexp.MustCompile(`https?://\S+`)
+	customEmojiRe = regexp.MustCompile(`<a?:\w+:\d+>`)
+)
+
+var strictness = map[string]float64{"low": 0.6, "medium": 1.0, "high": 1.5}
+
+type memberHeat struct {
+	heat        float64
+	last        time.Time
+	recent      []string // last few messages, normalized, for repeats
+	offences    int      // within the last day
+	lastOffence time.Time
+}
+
+type guildHeat struct {
+	mu          sync.Mutex
+	members     map[string]*memberHeat
+	maxedAt     map[string]time.Time // who hit max heat recently, for panic
+	panicUntil  time.Time
+	mentions    []time.Time // mentions by non-exempt members, for flood lockdown
+	lastFlood   time.Time
+	alertTimes  []time.Time
+	alertsMuted int
+}
+
+func (e *Engine) heatFor(guildID string) *guildHeat {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	g, ok := e.heat[guildID]
+	if !ok {
+		g = &guildHeat{members: map[string]*memberHeat{}, maxedAt: map[string]time.Time{}}
+		e.heat[guildID] = g
+	}
+	return g
+}
+
+func normalize(s string) string {
+	return strings.Join(strings.Fields(strings.ToLower(s)), " ")
+}
+
+func countEmoji(s string) int {
+	n := len(customEmojiRe.FindAllString(s, -1))
+	for _, r := range s {
+		if r >= 0x1F000 || (r >= 0x2600 && r <= 0x27BF) {
+			n++
+		}
+	}
+	return n
+}
+
+// MessageHeat scores one message. recent is the author's last few messages
+// (normalized) for spotting repeats. The second result is true when the
+// message is an instant maximum (an invite link).
+func MessageHeat(s *securityrepo.Settings, m *discordgo.Message, recent []string) (float64, bool, string) {
+	content := m.Content
+	lower := strings.ToLower(content)
+	if inviteRe.MatchString(lower) {
+		return maxHeat, true, "invite link"
+	}
+	reason := "spam"
+	h := heatBase
+	norm := normalize(content)
+	if norm != "" {
+		for _, r := range recent {
+			if r == norm {
+				h += heatRepeat
+				reason = "repeated messages"
+				break
+			}
+		}
+	}
+	mentions := len(m.Mentions) + len(m.MentionRoles)
+	h += float64(mentions) * heatMention
+	if m.MentionEveryone || strings.Contains(lower, "@everyone") || strings.Contains(lower, "@here") {
+		h += heatEveryone
+		reason = "mass mentions"
+	} else if mentions >= 3 {
+		reason = "mention spam"
+	}
+	h += float64(countEmoji(content)) * heatEmoji
+	if lines := strings.Count(content, "\n") + 1; lines > 4 {
+		h += float64(lines-4) * heatLine
+	}
+	h += float64(len([]rune(content))/100) * heatPer100Chars
+	h += float64(len(m.Attachments)+len(m.StickerItems)) * heatAttachment
+	h += float64(len(linkRe.FindAllString(content, -1))) * heatLink
+	for _, w := range s.HeatBlockedWords {
+		if w = strings.ToLower(strings.TrimSpace(w)); w != "" && strings.Contains(lower, w) {
+			h += heatBlockedWord
+			reason = "blocked word"
+			break
+		}
+	}
+	mult := strictness[s.HeatStrictness]
+	if mult == 0 {
+		mult = 1
+	}
+	return h * mult, false, reason
+}
+
+// heatExempt: bots, webhooks, the owner, trusted members and anyone who can
+// manage messages in the channel.
+func (e *Engine) heatExempt(ctx context.Context, m *discordgo.MessageCreate) bool {
+	if m.Author == nil || m.Author.Bot || m.WebhookID != "" {
+		return true
+	}
+	var roles []string
+	if m.Member != nil {
+		roles = m.Member.Roles
+	}
+	if e.IsTrusted(ctx, m.GuildID, m.Author.ID, nonNil(roles)) {
+		return true
+	}
+	if e.ChannelPerms != nil {
+		if p, err := e.ChannelPerms(m.Author.ID, m.ChannelID); err == nil &&
+			p&(discordgo.PermissionAdministrator|discordgo.PermissionManageMessages) != 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// OnMessage runs the heat system on a guild message.
+func (e *Engine) OnMessage(ctx context.Context, m *discordgo.MessageCreate) {
+	if m == nil || m.Message == nil || m.GuildID == "" {
+		return
+	}
+	s, _, err := e.load(ctx, m.GuildID)
+	if err != nil || !s.HeatEnabled {
+		return
+	}
+	if e.heatExempt(ctx, m) {
+		return
+	}
+	now := e.now()
+	g := e.heatFor(m.GuildID)
+
+	// Mention flood: lock the server once, then cool down.
+	if s.HeatLockdownMentions > 0 {
+		n := len(m.Mentions) + len(m.MentionRoles)
+		if m.MentionEveryone {
+			n += 10
+		}
+		if n > 0 && e.mentionFlood(g, now, n, s.HeatLockdownMentions) {
+			go e.floodLockdown(context.Background(), m.GuildID, s)
+		}
+	}
+
+	g.mu.Lock()
+	if now.Before(g.panicUntil) && m.Member != nil && !m.Member.JoinedAt.IsZero() && now.Sub(m.Member.JoinedAt) < panicNewMember {
+		g.mu.Unlock()
+		e.heatPunish(ctx, m, s, "heat panic: new member speaking during a spam wave", panicTimeout, securityrepo.ActionTimeout)
+		return
+	}
+	mh, ok := g.members[m.Author.ID]
+	if !ok {
+		if len(g.members) >= maxHeatUsers {
+			g.sweep(now)
+		}
+		mh = &memberHeat{}
+		g.members[m.Author.ID] = mh
+	}
+	if !mh.last.IsZero() {
+		mh.heat = math.Max(0, mh.heat-now.Sub(mh.last).Seconds()*heatDecayPerSec)
+	}
+	mh.last = now
+	add, instant, reason := MessageHeat(s, m.Message, mh.recent)
+	mh.heat += add
+	if norm := normalize(m.Content); norm != "" {
+		mh.recent = append(mh.recent, norm)
+		if len(mh.recent) > 3 {
+			mh.recent = mh.recent[len(mh.recent)-3:]
+		}
+	}
+	if mh.heat < maxHeat && !instant {
+		g.mu.Unlock()
+		return
+	}
+	// Over the top: reset, count the offence, and work out the timeout.
+	mh.heat = 0
+	if now.Sub(mh.lastOffence) > 24*time.Hour {
+		mh.offences = 0
+	}
+	mh.offences++
+	mh.lastOffence = now
+	timeout := time.Duration(s.HeatTimeoutMinutes) * time.Minute
+	if s.HeatEscalate && mh.offences > 1 {
+		timeout *= time.Duration(1 << min(mh.offences-1, 12))
+	}
+	if timeout > maxTimeout {
+		timeout = maxTimeout
+	}
+	// Heat panic: enough different members maxing out within a minute.
+	g.maxedAt[m.Author.ID] = now
+	for u, t := range g.maxedAt {
+		if now.Sub(t) > panicWindow {
+			delete(g.maxedAt, u)
+		}
+	}
+	startPanic := s.HeatPanicMembers > 0 && len(g.maxedAt) >= s.HeatPanicMembers && !now.Before(g.panicUntil)
+	if startPanic {
+		g.panicUntil = now.Add(panicDuration)
+	}
+	g.mu.Unlock()
+
+	e.heatPunish(ctx, m, s, reason, timeout, s.HeatAction)
+	if startPanic {
+		e.event(ctx, m.GuildID, securityrepo.EventHeatPanic, e.botID, "", fmt.Sprintf("%d members hit max heat within a minute", s.HeatPanicMembers))
+		e.send(ctx, m.GuildID, s, alert{ping: true, critical: true, embed: &discordgo.MessageEmbed{
+			Title:       "🔥 Spam wave: heat panic on",
+			Description: fmt.Sprintf("%d members hit max heat within a minute. For the next 10 minutes, anyone who joined in the last day is timed out as soon as they speak.", s.HeatPanicMembers),
+			Color:       colorAlert,
+		}})
+	}
+}
+
+func (g *guildHeat) sweep(now time.Time) {
+	for u, mh := range g.members {
+		cooled := mh.heat-now.Sub(mh.last).Seconds()*heatDecayPerSec <= 0
+		if cooled && now.Sub(mh.lastOffence) > 24*time.Hour {
+			delete(g.members, u)
+		}
+	}
+}
+
+// mentionFlood records n mentions and reports whether the guild just went
+// over the limit (once per cooldown).
+func (e *Engine) mentionFlood(g *guildHeat, now time.Time, n, limit int) bool {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	for i := 0; i < n && len(g.mentions) < 5000; i++ {
+		g.mentions = append(g.mentions, now)
+	}
+	cut := 0
+	for cut < len(g.mentions) && now.Sub(g.mentions[cut]) > mentionWindow {
+		cut++
+	}
+	g.mentions = g.mentions[cut:]
+	if len(g.mentions) >= limit && now.Sub(g.lastFlood) > floodCooldown {
+		g.lastFlood = now
+		g.mentions = nil
+		return true
+	}
+	return false
+}
+
+func (e *Engine) floodLockdown(ctx context.Context, guildID string, s *securityrepo.Settings) {
+	locked, failed, err := e.LockServer(ctx, guildID, e.botID)
+	desc := fmt.Sprintf("%d or more mentions within 30 seconds: every channel is locked (%d locked", s.HeatLockdownMentions, locked)
+	if failed > 0 {
+		desc += fmt.Sprintf(", %d failed", failed)
+	}
+	desc += "). Unlock with `/unlock server` once it's under control."
+	if err != nil {
+		desc = "A mention flood was detected but locking the server failed: " + clip(err.Error(), 200)
+	}
+	e.send(ctx, guildID, s, alert{ping: true, critical: true, embed: &discordgo.MessageEmbed{Title: "🔒 Mention flood: server locked", Description: desc, Color: colorAlert}})
+}
+
+// heatPunish deletes the message and applies the action. Alerts are capped
+// per minute so a spam wave can't flood the alert channel.
+func (e *Engine) heatPunish(ctx context.Context, m *discordgo.MessageCreate, s *securityrepo.Settings, reason string, timeout time.Duration, action string) {
+	if err := e.d.ChannelMessageDelete(m.ChannelID, m.ID, discordgo.WithAuditLogReason("Velox heat: "+reason)); err != nil {
+		log.Printf("security: deleting a hot message in guild %s: %v", m.GuildID, err)
+	}
+	var err error
+	if action == securityrepo.ActionTimeout {
+		if m.Author.ID == e.botID || e.IsOwner(m.GuildID, m.Author.ID) {
+			return
+		}
+		until := e.now().Add(timeout)
+		err = e.d.GuildMemberTimeout(m.GuildID, m.Author.ID, &until, discordgo.WithAuditLogReason(clip("Velox heat: "+reason, 400)))
+	} else {
+		err = e.punish(m.GuildID, m.Author, action, "heat: "+reason)
+	}
+	if err != nil {
+		log.Printf("security: heat action on %s in guild %s: %v", m.Author.ID, m.GuildID, err)
+		return
+	}
+	what := action
+	if action == securityrepo.ActionTimeout {
+		what = "timed out for " + humanize(timeout)
+	}
+	e.event(ctx, m.GuildID, securityrepo.EventHeat, e.botID, m.Author.ID, what+": "+reason)
+
+	g := e.heatFor(m.GuildID)
+	now := e.now()
+	g.mu.Lock()
+	cut := 0
+	for cut < len(g.alertTimes) && now.Sub(g.alertTimes[cut]) > time.Minute {
+		cut++
+	}
+	g.alertTimes = g.alertTimes[cut:]
+	allowed := len(g.alertTimes) < heatAlertsPerMin
+	muted := 0
+	if allowed {
+		g.alertTimes = append(g.alertTimes, now)
+		muted, g.alertsMuted = g.alertsMuted, 0
+	} else {
+		g.alertsMuted++
+	}
+	g.mu.Unlock()
+	if !allowed {
+		return
+	}
+	desc := fmt.Sprintf("<@%s> (%s) was %s: %s. Their message was deleted.", m.Author.ID, safeName(m.Author), what, reason)
+	if muted > 0 {
+		desc += fmt.Sprintf("\n(%d more since the last alert weren't posted, to keep this channel readable.)", muted)
+	}
+	e.send(ctx, m.GuildID, s, alert{embed: &discordgo.MessageEmbed{Title: "Heat", Description: desc, Color: colorWarn}})
+}
+
+func humanize(d time.Duration) string {
+	switch {
+	case d >= 24*time.Hour:
+		return fmt.Sprintf("%.0f days", d.Hours()/24)
+	case d >= time.Hour:
+		return fmt.Sprintf("%.0f hours", d.Hours())
+	default:
+		return fmt.Sprintf("%.0f minutes", math.Max(1, d.Minutes()))
+	}
+}

internal/security/joingate.go

@@ -0,0 +1,176 @@
+package security
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"regexp"
+	"strings"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Invite links in a name: discord.gg/x, discord.com/invite/x, dsc.gg/x and
+// the common lookalikes. Matched case-insensitively against the lowercased
+// name; the pattern is fixed, never built from user input.
+var inviteRe = regexp.MustCompile(`(discord(app)?\.(gg|com/invite|io|me|li)|dsc\.gg|\.gg/)`)
+
+var severity = map[string]int{
+	securityrepo.ActionOff: 0, securityrepo.ActionAlert: 1, securityrepo.ActionTimeout: 2,
+	securityrepo.ActionKick: 3, securityrepo.ActionBan: 4,
+}
+
+// GateResult is what the Join Gate decided about one member.
+type GateResult struct {
+	Action string // off, timeout, kick, ban
+	Reason string
+}
+
+// CheckJoin runs the Join Gate filters on a new member. When several match,
+// the strictest action wins. Bots are only checked for being unverified;
+// bots added by untrusted members are handled from the audit log.
+func CheckJoin(s *securityrepo.Settings, u *discordgo.User, now time.Time) GateResult {
+	var res GateResult
+	consider := func(action, reason string) {
+		if severity[action] > severity[res.Action] {
+			res = GateResult{Action: action, Reason: reason}
+		}
+	}
+	res.Action = securityrepo.ActionOff
+	if !s.JoinGateEnabled || u == nil {
+		return res
+	}
+
+	if u.Bot {
+		if u.PublicFlags&discordgo.UserFlagVerifiedBot == 0 {
+			consider(s.UnverifiedBot, "unverified bot")
+		}
+		return res
+	}
+
+	names := strings.ToLower(u.Username + " " + u.GlobalName)
+	if inviteRe.MatchString(names) {
+		consider(s.AdvertisingName, "invite link in name")
+	}
+	if s.UsernameFilter != securityrepo.ActionOff {
+		for _, p := range s.UsernamePatterns {
+			p = strings.ToLower(strings.TrimSpace(p))
+			if p != "" && strings.Contains(names, p) {
+				consider(s.UsernameFilter, "blocked word in name")
+				break
+			}
+		}
+	}
+	if created, err := discordgo.SnowflakeTimestamp(u.ID); err == nil {
+		if now.Sub(created) < time.Duration(s.MinAccountAgeDays)*24*time.Hour {
+			consider(s.NewAccount, fmt.Sprintf("account younger than %d days", s.MinAccountAgeDays))
+		}
+	}
+	if u.Avatar == "" {
+		consider(s.NoAvatar, "no avatar")
+	}
+	return res
+}
+
+// errProtected is returned when asked to punish the owner or the bot.
+var errProtected = errors.New("the owner and the bot are never punished")
+
+// punish applies a member action. It never touches the owner or the bot.
+func (e *Engine) punish(guildID string, u *discordgo.User, action, reason string) error {
+	if u == nil || u.ID == e.botID || e.IsOwner(guildID, u.ID) {
+		return errProtected
+	}
+	reason = clip("Velox security: "+reason, 400)
+	switch action {
+	case securityrepo.ActionTimeout:
+		until := e.now().Add(timeoutJoin)
+		return e.d.GuildMemberTimeout(guildID, u.ID, &until, discordgo.WithAuditLogReason(reason))
+	case securityrepo.ActionKick:
+		return e.d.GuildMemberDeleteWithReason(guildID, u.ID, reason)
+	case securityrepo.ActionBan:
+		return e.d.GuildBanCreateWithReason(guildID, u.ID, reason, 1)
+	}
+	return errors.New("no action " + action)
+}
+
+// OnMemberJoin runs every check for a new member: the join lock, the Join
+// Gate and raid detection. It reports whether the member was removed, so
+// welcome messages and default roles can be skipped.
+func (e *Engine) OnMemberJoin(ctx context.Context, guildID string, m *discordgo.Member) (removed bool) {
+	if m == nil || m.User == nil {
+		return false
+	}
+	s, _, err := e.load(ctx, guildID)
+	if err != nil {
+		log.Printf("security: settings for guild %s: %v", guildID, err)
+		return false
+	}
+
+	// 1. Join lockdown: everyone new is kicked or banned.
+	if s.JoinLock == securityrepo.ActionKick || s.JoinLock == securityrepo.ActionBan {
+		if err := e.punish(guildID, m.User, s.JoinLock, "joins are locked"); err != nil {
+			if !errors.Is(err, errProtected) {
+				log.Printf("security: join lock in guild %s: %v", guildID, err)
+			}
+			return false
+		}
+		e.raidJoin(ctx, guildID, s, m, true)
+		return true
+	}
+
+	// 2. Join Gate. A bot's verified flag isn't always in the join event, so
+	// it's read from Discord; if that fails the bot is left alone rather than
+	// risk kicking a verified one.
+	u := m.User
+	if u.Bot && s.JoinGateEnabled && s.UnverifiedBot != securityrepo.ActionOff {
+		fresh, err := e.d.User(u.ID)
+		if err != nil {
+			log.Printf("security: looking up bot %s: %v", u.ID, err)
+			a := e.raidJoin(ctx, guildID, s, m, false)
+			return a == securityrepo.ActionKick || a == securityrepo.ActionBan
+		}
+		u = fresh
+	}
+	gate := CheckJoin(s, u, e.now())
+	if gate.Action != securityrepo.ActionOff {
+		if err := e.punish(guildID, m.User, gate.Action, gate.Reason); err != nil {
+			if !errors.Is(err, errProtected) {
+				log.Printf("security: join gate in guild %s: %v", guildID, err)
+			}
+		} else {
+			removed = gate.Action == securityrepo.ActionKick || gate.Action == securityrepo.ActionBan
+			// During a raid the summary lists everyone; one alert per
+			// raider would flood the channel and Discord's rate limit.
+			if !e.RaidActive(guildID) {
+				e.event(ctx, guildID, securityrepo.EventJoinGate, e.botID, m.User.ID, gate.Action+": "+gate.Reason)
+				e.send(ctx, guildID, s, alert{embed: &discordgo.MessageEmbed{
+					Title:       "Join Gate",
+					Description: fmt.Sprintf("%s <@%s> (%s): %s.", actionPast(gate.Action), m.User.ID, safeName(m.User), gate.Reason),
+					Color:       colorWarn,
+				}})
+			}
+		}
+	}
+
+	// 3. Raid detection, which counts every join, gated or not.
+	if a := e.raidJoin(ctx, guildID, s, m, removed); a == securityrepo.ActionKick || a == securityrepo.ActionBan {
+		removed = true
+	}
+	return removed
+}
+
+func actionPast(a string) string {
+	switch a {
+	case securityrepo.ActionTimeout:
+		return "Timed out"
+	case securityrepo.ActionKick:
+		return "Kicked"
+	case securityrepo.ActionBan:
+		return "Banned"
+	}
+	return "Flagged"
+}

internal/security/listener.go

@@ -0,0 +1,90 @@
+package security
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"strconv"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/jackc/pgx/v5"
+)
+
+// StartCommandListener carries out the dashboard's requests
+// (security_commands rows announced with NOTIFY). The dashboard API checks
+// that the requester is the owner or trusted before inserting; the payload
+// is still validated here.
+func (e *Engine) StartCommandListener(ctx context.Context, connString string) error {
+	conn, err := pgx.Connect(ctx, connString)
+	if err != nil {
+		return fmt.Errorf("connect: %w", err)
+	}
+	defer conn.Close(ctx)
+	if _, err := conn.Exec(ctx, "LISTEN security_commands"); err != nil {
+		return fmt.Errorf("listen: %w", err)
+	}
+	e.ProcessCommands(ctx)
+	for {
+		if _, err := conn.WaitForNotification(ctx); err != nil {
+			return fmt.Errorf("waiting for notifications: %w", err)
+		}
+		e.ProcessCommands(ctx)
+	}
+}
+
+// ProcessCommands runs every pending command once and marks it done, even
+// when it fails (the error is logged; retrying would only fail again).
+func (e *Engine) ProcessCommands(ctx context.Context) {
+	cmds, err := e.st.ListUnprocessedCommands(ctx)
+	if err != nil {
+		log.Printf("security: listing dashboard commands: %v", err)
+		return
+	}
+	for _, c := range cmds {
+		if err := e.runCommand(ctx, c); err != nil {
+			log.Printf("security: dashboard command %d (%s) for guild %d: %v", c.ID, c.CommandType, c.GuildID, err)
+		}
+		if err := e.st.MarkCommandProcessed(ctx, c.ID); err != nil {
+			log.Printf("security: marking command %d done: %v", c.ID, err)
+		}
+	}
+}
+
+func (e *Engine) runCommand(ctx context.Context, c securityrepo.Command) error {
+	guildID, by := id(c.GuildID), id(c.RequestedBy)
+	switch c.CommandType {
+	case "end_raid":
+		return e.EndRaid(ctx, guildID, by)
+	case "unlock_server":
+		_, _, err := e.UnlockServer(ctx, guildID, by)
+		return err
+	case "unlock_joins":
+		return e.SetJoinLock(ctx, guildID, securityrepo.ActionOff, by)
+	case "snapshot":
+		_, _, err := e.TakeSnapshot(ctx, guildID, by)
+		return err
+	case "restore":
+		// Recreating many channels takes minutes under Discord's rate
+		// limits; don't hold up the other commands meanwhile.
+		go func() {
+			if _, err := e.Restore(context.Background(), guildID, by); err != nil {
+				log.Printf("security: restore for guild %s from the dashboard: %v", guildID, err)
+			}
+		}()
+		return nil
+	case "release_quarantine":
+		var p struct {
+			UserID string `json:"user_id"`
+		}
+		if err := json.Unmarshal(c.Payload, &p); err != nil {
+			return fmt.Errorf("bad payload: %w", err)
+		}
+		if _, err := strconv.ParseUint(p.UserID, 10, 64); err != nil {
+			return fmt.Errorf("bad user id %q", p.UserID)
+		}
+		return e.Release(ctx, guildID, p.UserID, by)
+	}
+	return fmt.Errorf("unknown command %q", c.CommandType)
+}

internal/security/lockdown.go

@@ -0,0 +1,166 @@
+package security
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// LockBits are what a lockdown denies @everyone: talking, threads, reactions.
+const LockBits = discordgo.PermissionSendMessages | discordgo.PermissionSendMessagesInThreads |
+	discordgo.PermissionCreatePublicThreads | discordgo.PermissionCreatePrivateThreads | discordgo.PermissionAddReactions
+
+// lockable reports whether a channel type has a chat to lock.
+func lockable(t discordgo.ChannelType) bool {
+	switch t {
+	case discordgo.ChannelTypeGuildText, discordgo.ChannelTypeGuildNews, discordgo.ChannelTypeGuildForum,
+		discordgo.ChannelTypeGuildVoice, discordgo.ChannelTypeGuildStageVoice, discordgo.ChannelTypeGuildMedia:
+		return true
+	}
+	return false
+}
+
+func everyoneOverwrite(ch *discordgo.Channel, guildID string) (allow, deny int64, found bool) {
+	for _, o := range ch.PermissionOverwrites {
+		if o.ID == guildID && o.Type == discordgo.PermissionOverwriteTypeRole {
+			return o.Allow, o.Deny, true
+		}
+	}
+	return 0, 0, false
+}
+
+// LockChannel stops @everyone from talking in a channel, remembering the
+// overwrite it had so UnlockChannel can put it back.
+func (e *Engine) LockChannel(ctx context.Context, guildID, channelID, by string, serverWide bool) error {
+	ch, err := e.d.Channel(channelID)
+	if err != nil {
+		return fmt.Errorf("looking up the channel: %w", err)
+	}
+	// Never act on a channel of another server, whatever ID was passed in.
+	if ch.GuildID != guildID {
+		return UserError("That channel isn't in this server.")
+	}
+	if !lockable(ch.Type) {
+		return UserError("That channel has no chat to lock.")
+	}
+	allow, deny, had := everyoneOverwrite(ch, guildID)
+	if err := e.st.SaveLockdown(ctx, securityrepo.Lockdown{
+		GuildID: parseID(guildID), ChannelID: parseID(channelID), HadOverwrite: had,
+		PreviousAllow: allow, PreviousDeny: deny, ServerWide: serverWide, LockedBy: parseID(by),
+	}); err != nil {
+		return err
+	}
+	if err := e.d.ChannelPermissionSet(channelID, guildID, discordgo.PermissionOverwriteTypeRole, allow&^LockBits, deny|LockBits,
+		discordgo.WithAuditLogReason("Velox lockdown")); err != nil {
+		_ = e.st.DeleteLockdown(ctx, parseID(guildID), parseID(channelID))
+		return fmt.Errorf("locking: %w", err)
+	}
+	if !serverWide {
+		e.event(ctx, guildID, securityrepo.EventLocked, by, channelID, "channel")
+	}
+	return nil
+}
+
+// UnlockChannel restores the lock bits of @everyone's overwrite to what they
+// were before. Anything else changed in the overwrite during the lockdown is
+// kept. Unlocking relaxes protection, so callers must check the actor first.
+func (e *Engine) UnlockChannel(ctx context.Context, guildID, channelID, by string) error {
+	rec, err := e.st.GetLockdown(ctx, parseID(guildID), parseID(channelID))
+	if err != nil {
+		return err
+	}
+	if rec == nil {
+		return UserError("That channel isn't locked by Velox.")
+	}
+	ch, err := e.d.Channel(channelID)
+	if err != nil {
+		// The channel is gone: nothing to unlock.
+		return e.st.DeleteLockdown(ctx, rec.GuildID, rec.ChannelID)
+	}
+	allow, deny, _ := everyoneOverwrite(ch, guildID)
+	allow = allow&^LockBits | rec.PreviousAllow&LockBits
+	deny = deny&^LockBits | rec.PreviousDeny&LockBits
+
+	reason := discordgo.WithAuditLogReason("Velox unlock")
+	if allow == 0 && deny == 0 && !rec.HadOverwrite {
+		err = e.d.ChannelPermissionDelete(channelID, guildID, reason)
+	} else {
+		err = e.d.ChannelPermissionSet(channelID, guildID, discordgo.PermissionOverwriteTypeRole, allow, deny, reason)
+	}
+	if err != nil {
+		return fmt.Errorf("unlocking: %w", err)
+	}
+	if err := e.st.DeleteLockdown(ctx, rec.GuildID, rec.ChannelID); err != nil {
+		return err
+	}
+	if !rec.ServerWide {
+		e.event(ctx, guildID, securityrepo.EventUnlocked, by, channelID, "channel")
+	}
+	return nil
+}
+
+// LockServer locks every channel with a chat.
+func (e *Engine) LockServer(ctx context.Context, guildID, by string) (locked, failed int, err error) {
+	chans, err := e.d.GuildChannels(guildID)
+	if err != nil {
+		return 0, 0, fmt.Errorf("listing channels: %w", err)
+	}
+	for _, ch := range chans {
+		if !lockable(ch.Type) {
+			continue
+		}
+		if err := e.LockChannel(ctx, guildID, ch.ID, by, true); err != nil {
+			log.Printf("security: locking channel %s in guild %s: %v", ch.ID, guildID, err)
+			failed++
+			continue
+		}
+		locked++
+	}
+	e.event(ctx, guildID, securityrepo.EventLocked, by, "", fmt.Sprintf("server: %d channels locked, %d failed", locked, failed))
+	return locked, failed, nil
+}
+
+// UnlockServer unlocks every channel the last server lockdown locked.
+func (e *Engine) UnlockServer(ctx context.Context, guildID, by string) (unlocked, failed int, err error) {
+	recs, err := e.st.ListLockdowns(ctx, parseID(guildID), true)
+	if err != nil {
+		return 0, 0, err
+	}
+	if len(recs) == 0 {
+		return 0, 0, UserError("The server isn't locked by Velox.")
+	}
+	for _, r := range recs {
+		if err := e.UnlockChannel(ctx, guildID, id(r.ChannelID), by); err != nil {
+			log.Printf("security: unlocking channel %d in guild %s: %v", r.ChannelID, guildID, err)
+			failed++
+			continue
+		}
+		unlocked++
+	}
+	e.event(ctx, guildID, securityrepo.EventUnlocked, by, "", fmt.Sprintf("server: %d channels unlocked, %d failed", unlocked, failed))
+	return unlocked, failed, nil
+}
+
+// SetJoinLock turns the join lockdown on ("kick" or "ban") or off. Turning it
+// off relaxes protection, so callers must check the actor first.
+func (e *Engine) SetJoinLock(ctx context.Context, guildID, mode, by string) error {
+	switch mode {
+	case securityrepo.ActionOff, securityrepo.ActionKick, securityrepo.ActionBan:
+	default:
+		return UserError("Joins can be locked with kick or ban.")
+	}
+	if err := e.st.SetJoinLock(ctx, parseID(guildID), mode); err != nil {
+		return err
+	}
+	e.Invalidate(guildID)
+	kind := securityrepo.EventLocked
+	if mode == securityrepo.ActionOff {
+		kind = securityrepo.EventUnlocked
+	}
+	e.event(ctx, guildID, kind, by, "", "joins: "+mode)
+	return nil
+}

internal/security/nuke.go

@@ -0,0 +1,446 @@
+package security
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strconv"
+	"sync"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// nukeCounter counts destructive actions per server, person and kind over a
+// sliding window, and remembers whom it just punished so one nuke attempt
+// is answered once.
+type nukeCounter struct {
+	mu       sync.Mutex
+	hits     map[string][]time.Time
+	punished map[string]time.Time
+}
+
+const (
+	maxHitsPerKey  = 200
+	punishCooldown = time.Minute
+)
+
+func newNukeCounter() *nukeCounter {
+	return &nukeCounter{hits: map[string][]time.Time{}, punished: map[string]time.Time{}}
+}
+
+// add records a hit and returns how many fall inside the window.
+func (c *nukeCounter) add(key string, now time.Time, window time.Duration) int {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	h := append(c.hits[key], now)
+	cut := 0
+	for cut < len(h) && now.Sub(h[cut]) > window {
+		cut++
+	}
+	h = h[cut:]
+	if len(h) > maxHitsPerKey {
+		h = h[len(h)-maxHitsPerKey:]
+	}
+	c.hits[key] = h
+	// Opportunistic cleanup so the map can't grow forever.
+	if len(c.hits) > 5000 {
+		for k, v := range c.hits {
+			if len(v) == 0 || now.Sub(v[len(v)-1]) > window {
+				delete(c.hits, k)
+			}
+		}
+	}
+	return len(h)
+}
+
+// claim reports whether this person may be punished now (not punished in the
+// last minute), and marks them.
+func (c *nukeCounter) claim(key string, now time.Time) bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if t, ok := c.punished[key]; ok && now.Sub(t) < punishCooldown {
+		return false
+	}
+	c.punished[key] = now
+	if len(c.punished) > 5000 {
+		for k, t := range c.punished {
+			if now.Sub(t) > punishCooldown {
+				delete(c.punished, k)
+			}
+		}
+	}
+	return true
+}
+
+func changeKey(c *discordgo.AuditLogChange) string {
+	if c == nil || c.Key == nil {
+		return ""
+	}
+	return string(*c.Key)
+}
+
+func permValue(v any) int64 {
+	switch x := v.(type) {
+	case string:
+		n, _ := strconv.ParseInt(x, 10, 64)
+		return n
+	case float64:
+		return int64(x)
+	}
+	return 0
+}
+
+// Classify maps an audit log entry to a limit key, or flags it as always
+// forbidden for untrusted members (instant). rolePerms looks up a role's
+// permissions for role grants.
+func Classify(entry *discordgo.AuditLogEntry, rolePerms func(roleID string) int64) (key string, instant bool, what string) {
+	if entry == nil || entry.ActionType == nil {
+		return "", false, ""
+	}
+	switch *entry.ActionType {
+	case discordgo.AuditLogActionChannelCreate:
+		return securityrepo.LimitChannelCreate, false, "created channels"
+	case discordgo.AuditLogActionChannelDelete:
+		return securityrepo.LimitChannelDelete, false, "deleted channels"
+	case discordgo.AuditLogActionRoleDelete:
+		return securityrepo.LimitRoleDelete, false, "deleted roles"
+	case discordgo.AuditLogActionMemberBanAdd:
+		return securityrepo.LimitBan, false, "banned members"
+	case discordgo.AuditLogActionMemberKick:
+		return securityrepo.LimitKick, false, "kicked members"
+	case discordgo.AuditLogActionWebhookCreate:
+		return securityrepo.LimitWebhookCreate, false, "created webhooks"
+	case discordgo.AuditLogActionMemberPrune:
+		return "", true, "pruned members"
+	case discordgo.AuditLogActionRoleCreate:
+		for _, c := range entry.Changes {
+			if changeKey(c) == "permissions" && permValue(c.NewValue)&DangerousPerms != 0 {
+				return "", true, "created a role with dangerous permissions"
+			}
+		}
+		return securityrepo.LimitRoleCreate, false, "created roles"
+	case discordgo.AuditLogActionRoleUpdate:
+		for _, c := range entry.Changes {
+			if changeKey(c) == "permissions" {
+				added := permValue(c.NewValue) &^ permValue(c.OldValue)
+				if added&DangerousPerms != 0 {
+					return "", true, "gave a role dangerous permissions"
+				}
+			}
+		}
+	case discordgo.AuditLogActionMemberRoleUpdate:
+		for _, c := range entry.Changes {
+			if changeKey(c) != "$add" {
+				continue
+			}
+			list, _ := c.NewValue.([]any)
+			for _, item := range list {
+				if r, ok := item.(map[string]any); ok {
+					if rid, _ := r["id"].(string); rid != "" && rolePerms != nil && rolePerms(rid)&DangerousPerms != 0 {
+						return "", true, "gave someone a role with dangerous permissions"
+					}
+				}
+			}
+		}
+	case discordgo.AuditLogActionGuildUpdate:
+		for _, c := range entry.Changes {
+			if changeKey(c) == "vanity_url_code" {
+				return "", true, "changed the vanity URL"
+			}
+		}
+	}
+	return "", false, ""
+}
+
+// OnAuditLogEntry watches what members do: bots added by untrusted members
+// (Join Gate) and destructive actions over the limits (anti-nuke).
+func (e *Engine) OnAuditLogEntry(ctx context.Context, guildID string, entry *discordgo.AuditLogEntry) {
+	if entry == nil || entry.ActionType == nil || entry.UserID == "" {
+		return
+	}
+	s, _, err := e.load(ctx, guildID)
+	if err != nil {
+		log.Printf("security: settings for guild %s: %v", guildID, err)
+		return
+	}
+
+	if *entry.ActionType == discordgo.AuditLogActionBotAdd {
+		e.checkBotAdd(ctx, guildID, s, entry)
+		return
+	}
+	if !s.AntiNukeEnabled || !worthChecking(entry) {
+		return
+	}
+
+	// Role grants need care: someone could give themselves (or an alt) a
+	// trusted role to slip past everything below. Roles added by this very
+	// entry never count towards the actor's own trust, and an untrusted
+	// member granting a trusted role is stopped and the role taken back.
+	added := addedRoles(entry)
+	var actorRoles []string
+	if m, err := e.d.GuildMember(guildID, entry.UserID); err == nil {
+		actorRoles = m.Roles
+		if entry.TargetID == entry.UserID {
+			actorRoles = without(actorRoles, added)
+		}
+	}
+	if e.IsTrusted(ctx, guildID, entry.UserID, nonNil(actorRoles)) {
+		return
+	}
+
+	key, instant, what := Classify(entry, func(roleID string) int64 { return e.rolePerms(guildID, roleID) })
+	if granted := e.trustedAmong(ctx, guildID, added); len(granted) > 0 {
+		instant, what = true, "gave someone a trusted role"
+		e.revokeRoles(guildID, entry.TargetID, granted)
+	}
+	if *entry.ActionType == discordgo.AuditLogActionRoleUpdate && e.isBotRole(guildID, entry.TargetID) {
+		instant, what = true, "changed Velox's own role"
+	}
+	if key == "" && !instant {
+		return
+	}
+	who := guildID + "|" + entry.UserID
+	if !instant {
+		limit, ok := s.AntiNukeLimits[key]
+		if !ok {
+			limit = securityrepo.DefaultLimits()[key]
+		}
+		n := e.nukes.add(who+"|"+key, e.now(), time.Duration(s.AntiNukeWindowSeconds)*time.Second)
+		if n <= limit {
+			return
+		}
+		what = fmt.Sprintf("%s %d times in %d seconds (limit %d)", what, n, s.AntiNukeWindowSeconds, limit)
+	}
+	if !e.nukes.claim(who, e.now()) {
+		return
+	}
+	e.stopNuke(ctx, guildID, s, entry.UserID, what)
+}
+
+func (e *Engine) rolePerms(guildID, roleID string) int64 {
+	for _, r := range e.guildRoles(guildID) {
+		if r.ID == roleID {
+			return r.Permissions
+		}
+	}
+	return 0
+}
+
+// worthChecking skips audit log entries that can never trigger anti-nuke
+// before anything is looked up on Discord. A busy server writes many entries
+// (message deletes, nickname changes...), and lookups for each would eat
+// into the rate limit the bot needs most during an attack.
+func worthChecking(entry *discordgo.AuditLogEntry) bool {
+	switch *entry.ActionType {
+	case discordgo.AuditLogActionChannelCreate, discordgo.AuditLogActionChannelDelete,
+		discordgo.AuditLogActionRoleCreate, discordgo.AuditLogActionRoleDelete, discordgo.AuditLogActionRoleUpdate,
+		discordgo.AuditLogActionMemberBanAdd, discordgo.AuditLogActionMemberKick, discordgo.AuditLogActionMemberPrune,
+		discordgo.AuditLogActionWebhookCreate:
+		return true
+	case discordgo.AuditLogActionMemberRoleUpdate:
+		return len(addedRoles(entry)) > 0 // removing roles is harmless
+	case discordgo.AuditLogActionGuildUpdate:
+		for _, c := range entry.Changes {
+			if changeKey(c) == "vanity_url_code" {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+const roleCacheTTL = 10 * time.Second
+
+type cachedRoles struct {
+	roles []*discordgo.Role
+	at    time.Time
+}
+
+// guildRoles returns the guild's roles, cached briefly. Staleness can't hide
+// an escalation: creating or editing a role with dangerous permissions is
+// caught from its own audit log entry.
+func (e *Engine) guildRoles(guildID string) []*discordgo.Role {
+	e.mu.Lock()
+	c, ok := e.roleCache[guildID]
+	e.mu.Unlock()
+	if ok && e.now().Sub(c.at) < roleCacheTTL {
+		return c.roles
+	}
+	roles, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return nil
+	}
+	e.mu.Lock()
+	if e.roleCache == nil {
+		e.roleCache = map[string]cachedRoles{}
+	}
+	e.roleCache[guildID] = cachedRoles{roles: roles, at: e.now()}
+	e.mu.Unlock()
+	return roles
+}
+
+func (e *Engine) stopNuke(ctx context.Context, guildID string, s *securityrepo.Settings, userID, what string) {
+	reason := "anti-nuke: " + what
+	e.event(ctx, guildID, securityrepo.EventNuke, userID, userID, what)
+
+	desc := fmt.Sprintf("<@%s> %s.", userID, what)
+	if err := e.Quarantine(ctx, guildID, userID, reason); err != nil {
+		log.Printf("security: quarantining %s in guild %s: %v", userID, guildID, err)
+		desc += "\n⚠️ I couldn't fully quarantine them: " + clip(err.Error(), 300) +
+			"\nMove the Velox role above their highest role and give it Manage Roles, Moderate Members and Kick Members."
+	} else {
+		desc += "\nThey were quarantined: roles removed (saved) and timed out. Release them with `/security release` if this was a mistake."
+	}
+	if s.AntiNukeLockServer {
+		locked, failed, err := e.LockServer(ctx, guildID, e.botID)
+		switch {
+		case err != nil:
+			desc += "\n⚠️ Locking the server failed: " + clip(err.Error(), 200)
+		default:
+			desc += fmt.Sprintf("\nThe server is locked (%d channels", locked)
+			if failed > 0 {
+				desc += fmt.Sprintf(", %d couldn't be locked", failed)
+			}
+			desc += "). Unlock it with `/unlock server`."
+		}
+	}
+	if s.AntiNukeAutoRestore {
+		desc += "\nRestoring deleted roles and channels from the latest snapshot; a report follows."
+		go func() {
+			// Give the attack a moment to stop, then rebuild.
+			time.Sleep(5 * time.Second)
+			if _, err := e.Restore(context.Background(), guildID, e.botID); err != nil {
+				log.Printf("security: auto restore in guild %s: %v", guildID, err)
+			}
+		}()
+	}
+	e.send(ctx, guildID, s, alert{
+		ping: true, pingOwner: true, critical: true,
+		embed: &discordgo.MessageEmbed{
+			Title: "🛡️ Nuke attempt stopped", Description: desc, Color: colorAlert,
+			Timestamp: e.now().UTC().Format(time.RFC3339),
+		},
+	})
+}
+
+// checkBotAdd removes a bot that someone other than the owner or a trusted
+// member added, when the Join Gate is on.
+func (e *Engine) checkBotAdd(ctx context.Context, guildID string, s *securityrepo.Settings, entry *discordgo.AuditLogEntry) {
+	if !s.JoinGateEnabled || s.UnauthorizedBot == securityrepo.ActionOff || entry.TargetID == "" {
+		return
+	}
+	if e.IsTrusted(ctx, guildID, entry.UserID, nil) {
+		return
+	}
+	bot := &discordgo.User{ID: entry.TargetID}
+	if err := e.punish(guildID, bot, s.UnauthorizedBot, fmt.Sprintf("bot added by %s, who isn't trusted", entry.UserID)); err != nil {
+		log.Printf("security: removing unauthorized bot %s in guild %s: %v", entry.TargetID, guildID, err)
+		return
+	}
+	e.event(ctx, guildID, securityrepo.EventUnauthorizedBot, entry.UserID, entry.TargetID, s.UnauthorizedBot)
+	e.send(ctx, guildID, s, alert{
+		ping: true, critical: true,
+		embed: &discordgo.MessageEmbed{
+			Title:       "Bot removed",
+			Description: fmt.Sprintf("<@%s> added the bot <@%s> but isn't on the trusted list, so the bot was %s.", entry.UserID, entry.TargetID, map[string]string{securityrepo.ActionKick: "kicked", securityrepo.ActionBan: "banned"}[s.UnauthorizedBot]),
+			Color:       colorWarn,
+		},
+	})
+}
+
+// addedRoles lists the role IDs a member role update added.
+func addedRoles(entry *discordgo.AuditLogEntry) []string {
+	if entry.ActionType == nil || *entry.ActionType != discordgo.AuditLogActionMemberRoleUpdate {
+		return nil
+	}
+	var out []string
+	for _, c := range entry.Changes {
+		if changeKey(c) != "$add" {
+			continue
+		}
+		list, _ := c.NewValue.([]any)
+		for _, item := range list {
+			if r, ok := item.(map[string]any); ok {
+				if rid, _ := r["id"].(string); rid != "" {
+					out = append(out, rid)
+				}
+			}
+		}
+	}
+	return out
+}
+
+func without(list, remove []string) []string {
+	drop := map[string]bool{}
+	for _, r := range remove {
+		drop[r] = true
+	}
+	out := []string{}
+	for _, r := range list {
+		if !drop[r] {
+			out = append(out, r)
+		}
+	}
+	return out
+}
+
+// nonNil keeps an empty role list from meaning "look the member up".
+func nonNil(roles []string) []string {
+	if roles == nil {
+		return []string{}
+	}
+	return roles
+}
+
+// trustedAmong returns which of the roles are on the trusted list.
+func (e *Engine) trustedAmong(ctx context.Context, guildID string, roles []string) []string {
+	if len(roles) == 0 {
+		return nil
+	}
+	_, trusted, err := e.load(ctx, guildID)
+	if err != nil {
+		return nil
+	}
+	var out []string
+	for _, r := range roles {
+		for _, t := range trusted {
+			if t.Kind == "role" && id(t.TargetID) == r {
+				out = append(out, r)
+			}
+		}
+	}
+	return out
+}
+
+// revokeRoles takes roles back from a member (best effort; never the owner).
+func (e *Engine) revokeRoles(guildID, userID string, roles []string) {
+	if userID == "" || e.IsOwner(guildID, userID) {
+		return
+	}
+	m, err := e.d.GuildMember(guildID, userID)
+	if err != nil {
+		return
+	}
+	next := without(m.Roles, roles)
+	if _, err := e.d.GuildMemberEdit(guildID, userID, &discordgo.GuildMemberParams{Roles: &next},
+		discordgo.WithAuditLogReason("Velox anti-nuke: trusted role granted by someone untrusted")); err != nil {
+		log.Printf("security: taking back trusted roles from %s in guild %s: %v", userID, guildID, err)
+	}
+}
+
+// isBotRole reports whether roleID is one of Velox's own roles.
+func (e *Engine) isBotRole(guildID, roleID string) bool {
+	m, err := e.d.GuildMember(guildID, e.botID)
+	if err != nil {
+		return false
+	}
+	for _, r := range m.Roles {
+		if r == roleID {
+			return true
+		}
+	}
+	return false
+}

internal/security/quarantine.go

@@ -0,0 +1,187 @@
+package security
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// usableQuarantineRole returns the configured quarantine role if it is safe
+// to hand out right now: it exists, isn't @everyone or managed by an
+// integration, and has none of the dangerous permissions. Checked at use, so
+// a role that gained permissions since it was configured is never assigned.
+func usableQuarantineRole(s *securityrepo.Settings, guildID string, roles []*discordgo.Role) string {
+	if s.QuarantineRoleID == 0 || id(s.QuarantineRoleID) == guildID {
+		return ""
+	}
+	for _, r := range roles {
+		if r.ID == id(s.QuarantineRoleID) {
+			if r.Managed || r.Permissions&DangerousPerms != 0 {
+				return ""
+			}
+			return r.ID
+		}
+	}
+	return ""
+}
+
+// Quarantine neutralises a member: every role it can remove is taken away
+// (and saved, so it can be given back), the quarantine role is added if one
+// is configured, and the member is timed out for the longest Discord allows.
+// Bots are kicked instead, since their own integration role can't be
+// removed. The owner and the bot itself are never touched.
+func (e *Engine) Quarantine(ctx context.Context, guildID, userID, reason string) error {
+	if userID == "" || userID == e.botID || e.IsOwner(guildID, userID) {
+		return errors.New("refusing to quarantine the owner or the bot")
+	}
+	s, _, err := e.load(ctx, guildID)
+	if err != nil {
+		return err
+	}
+	m, err := e.d.GuildMember(guildID, userID)
+	if err != nil {
+		return fmt.Errorf("looking up the member: %w", err)
+	}
+	if m.User != nil && m.User.Bot {
+		return e.d.GuildMemberDeleteWithReason(guildID, userID, clip("Velox anti-nuke: "+reason, 400))
+	}
+	roles, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return fmt.Errorf("listing roles: %w", err)
+	}
+	managed := map[string]bool{}
+	for _, r := range roles {
+		if r.Managed {
+			managed[r.ID] = true
+		}
+	}
+
+	var keep []string
+	var previous []int64
+	for _, r := range m.Roles {
+		if managed[r] {
+			keep = append(keep, r) // can't be removed (e.g. a Nitro booster role)
+		} else {
+			previous = append(previous, parseID(r))
+		}
+	}
+	qRole := usableQuarantineRole(s, guildID, roles)
+	withRole := keep
+	if qRole != "" {
+		withRole = append(append([]string(nil), keep...), qRole)
+	}
+
+	// Save first: if Discord fails half-way, the roles are still on record.
+	if err := e.st.SaveQuarantine(ctx, securityrepo.Quarantine{
+		GuildID: parseID(guildID), UserID: parseID(userID), PreviousRoleIDs: previous, Reason: clip(reason, 300),
+	}); err != nil {
+		return fmt.Errorf("saving the quarantine: %w", err)
+	}
+
+	audit := discordgo.WithAuditLogReason(clip("Velox anti-nuke: "+reason, 400))
+	var errs []error
+	if _, err := e.d.GuildMemberEdit(guildID, userID, &discordgo.GuildMemberParams{Roles: &withRole}, audit); err != nil {
+		// A quarantine role Velox can't assign (e.g. moved above its own
+		// role) must not stop the roles from being removed: retry without it.
+		if qRole == "" {
+			errs = append(errs, fmt.Errorf("removing roles: %w", err))
+		} else if _, err2 := e.d.GuildMemberEdit(guildID, userID, &discordgo.GuildMemberParams{Roles: &keep}, audit); err2 != nil {
+			errs = append(errs, fmt.Errorf("removing roles: %w", err2))
+		} else {
+			log.Printf("security: quarantine role %s couldn't be assigned in guild %s (%v); roles were still removed", qRole, guildID, err)
+		}
+	}
+	until := e.now().Add(timeoutQuarantine)
+	if err := e.d.GuildMemberTimeout(guildID, userID, &until, audit); err != nil {
+		errs = append(errs, fmt.Errorf("timing out: %w", err))
+	}
+	e.event(ctx, guildID, securityrepo.EventQuarantined, e.botID, userID, reason)
+	return errors.Join(errs...)
+}
+
+// Release undoes a quarantine: the saved roles that still exist are given
+// back, the quarantine role and the timeout are removed. Releasing relaxes
+// protection, so callers must check the actor first.
+func (e *Engine) Release(ctx context.Context, guildID, userID, by string) error {
+	rec, err := e.st.GetQuarantine(ctx, parseID(guildID), parseID(userID))
+	if err != nil {
+		return err
+	}
+	if rec == nil {
+		return UserError("That member isn't quarantined.")
+	}
+	s, _, err := e.load(ctx, guildID)
+	if err != nil {
+		return err
+	}
+	m, err := e.d.GuildMember(guildID, userID)
+	if err != nil {
+		// They left: there's nothing to give back.
+		if derr := e.st.DeleteQuarantine(ctx, parseID(guildID), parseID(userID)); derr != nil {
+			return derr
+		}
+		e.event(ctx, guildID, securityrepo.EventReleased, by, userID, "member had left")
+		return nil
+	}
+	roles, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return fmt.Errorf("listing roles: %w", err)
+	}
+	exists := map[string]bool{}
+	for _, r := range roles {
+		if !r.Managed && r.ID != guildID {
+			exists[r.ID] = true
+		}
+	}
+	qRole := ""
+	if s.QuarantineRoleID != 0 {
+		qRole = id(s.QuarantineRoleID)
+	}
+
+	seen := map[string]bool{}
+	var next []string
+	add := func(r string) {
+		if !seen[r] && r != qRole {
+			seen[r] = true
+			next = append(next, r)
+		}
+	}
+	for _, r := range m.Roles {
+		add(r)
+	}
+	for _, r := range rec.PreviousRoleIDs {
+		if exists[id(r)] {
+			add(id(r))
+		}
+	}
+
+	audit := discordgo.WithAuditLogReason("Velox security: quarantine released")
+	if _, err := e.d.GuildMemberEdit(guildID, userID, &discordgo.GuildMemberParams{Roles: &next}, audit); err != nil {
+		return fmt.Errorf("giving the roles back: %w", err)
+	}
+	if err := e.d.GuildMemberTimeout(guildID, userID, nil, audit); err != nil {
+		log.Printf("security: removing the timeout of %s in guild %s: %v", userID, guildID, err)
+	}
+	if err := e.st.DeleteQuarantine(ctx, parseID(guildID), parseID(userID)); err != nil {
+		return err
+	}
+	e.event(ctx, guildID, securityrepo.EventReleased, by, userID, fmt.Sprintf("%d roles given back", len(rec.PreviousRoleIDs)))
+	e.send(ctx, guildID, s, alert{embed: &discordgo.MessageEmbed{
+		Title:       "Quarantine released",
+		Description: fmt.Sprintf("<@%s> was released by <@%s> and got their roles back.", userID, by),
+		Color:       colorOK,
+		Timestamp:   e.now().UTC().Format(time.RFC3339),
+	}})
+	return nil
+}
+
+// Quarantines lists who is quarantined in a guild.
+func (e *Engine) Quarantines(ctx context.Context, guildID string) ([]securityrepo.Quarantine, error) {
+	return e.st.ListQuarantines(ctx, parseID(guildID))
+}

internal/security/raid.go

@@ -0,0 +1,333 @@
+package security
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"strings"
+	"sync"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Memory bounds per server, so a huge raid can't exhaust the bot.
+const (
+	maxRecentJoins = 500
+	maxCaught      = 20000
+)
+
+// CustomIDEndRaid is the alert's "End raid" button.
+const CustomIDEndRaid = "security:endraid"
+
+type joinRec struct {
+	user    *discordgo.User
+	at      time.Time
+	handled bool // already removed by the join lock or Join Gate
+}
+
+type caughtRec struct {
+	userID, name, action string
+}
+
+type raid struct {
+	mu            sync.Mutex
+	joins         []joinRec
+	active        bool
+	started       time.Time
+	lastJoin      time.Time
+	caught        []caughtRec
+	caughtTotal   int
+	pausedInvites bool
+}
+
+func (e *Engine) raidFor(guildID string) *raid {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	r, ok := e.raids[guildID]
+	if !ok {
+		r = &raid{}
+		e.raids[guildID] = r
+	}
+	return r
+}
+
+// RaidActive reports whether raid mode is on in a guild.
+func (e *Engine) RaidActive(guildID string) bool {
+	e.mu.Lock()
+	r, ok := e.raids[guildID]
+	e.mu.Unlock()
+	if !ok {
+		return false
+	}
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return r.active
+}
+
+// raidJoin records a join and, during a raid, acts on the raiders. It returns
+// the action taken on this member ("" when none).
+func (e *Engine) raidJoin(ctx context.Context, guildID string, s *securityrepo.Settings, m *discordgo.Member, handled bool) string {
+	if !s.AntiRaidEnabled {
+		return ""
+	}
+	now := e.now()
+	window := time.Duration(s.RaidJoinSeconds) * time.Second
+	r := e.raidFor(guildID)
+
+	r.mu.Lock()
+	r.joins = append(r.joins, joinRec{user: m.User, at: now, handled: handled})
+	cut := 0
+	for cut < len(r.joins) && now.Sub(r.joins[cut].at) > window {
+		cut++
+	}
+	r.joins = r.joins[cut:]
+	if len(r.joins) > maxRecentJoins {
+		r.joins = r.joins[len(r.joins)-maxRecentJoins:]
+	}
+	r.lastJoin = now
+
+	var targets []joinRec
+	starting := false
+	switch {
+	case !r.active && len(r.joins) >= s.RaidJoinCount:
+		// Raid starts: everyone in the burst that triggered it is a raider.
+		starting = true
+		r.active, r.started, r.caught, r.caughtTotal, r.pausedInvites = true, now, nil, 0, false
+		targets = append(targets, r.joins...)
+	case r.active:
+		targets = []joinRec{{user: m.User, at: now, handled: handled}}
+	}
+	r.mu.Unlock()
+
+	if starting {
+		e.startRaid(ctx, guildID, s, len(targets))
+	}
+
+	action := s.RaidAction
+	thisMember := ""
+	for _, t := range targets {
+		did := action
+		if t.handled || action == securityrepo.ActionAlert {
+			did = "flagged"
+		} else if err := e.punish(guildID, t.user, action, "raid"); errors.Is(err, errProtected) {
+			did = "skipped"
+		} else if err != nil {
+			log.Printf("security: raid action on %s in guild %s: %v", t.user.ID, guildID, err)
+			did = "failed"
+		}
+		r.mu.Lock()
+		r.caughtTotal++
+		keep := len(r.caught) < maxCaught
+		if keep {
+			r.caught = append(r.caught, caughtRec{userID: t.user.ID, name: safeName(t.user), action: did})
+		}
+		r.mu.Unlock()
+		if keep {
+			if err := e.st.AddRaidCaught(ctx, parseID(guildID), securityrepo.Caught{UserID: parseID(t.user.ID), Action: did, Name: safeName(t.user)}); err != nil {
+				log.Printf("security: recording raider %s in guild %s: %v", t.user.ID, guildID, err)
+			}
+		}
+		if t.user.ID == m.User.ID && did == action {
+			thisMember = action
+		}
+	}
+	if len(targets) > 0 {
+		e.persistRaid(ctx, guildID, r)
+	}
+	return thisMember
+}
+
+// persistRaid writes the raid's state so a restart can resume it.
+func (e *Engine) persistRaid(ctx context.Context, guildID string, r *raid) {
+	r.mu.Lock()
+	x := securityrepo.Raid{GuildID: parseID(guildID), StartedAt: r.started, LastJoinAt: r.lastJoin, InvitesPaused: r.pausedInvites, CaughtTotal: r.caughtTotal}
+	active := r.active
+	r.mu.Unlock()
+	if !active {
+		return
+	}
+	if err := e.st.SaveRaid(ctx, x); err != nil {
+		log.Printf("security: saving raid state for guild %s: %v", guildID, err)
+	}
+}
+
+// ResumeRaids reloads raids that were in progress when the bot stopped, so
+// raid mode stays on, its quiet timer keeps counting from the last join, and
+// paused invites are resumed when it ends.
+func (e *Engine) ResumeRaids(ctx context.Context) {
+	raids, err := e.st.ListRaids(ctx)
+	if err != nil {
+		log.Printf("security: loading raids in progress: %v", err)
+		return
+	}
+	for _, x := range raids {
+		r := e.raidFor(id(x.GuildID))
+		r.mu.Lock()
+		r.active, r.started, r.lastJoin, r.pausedInvites, r.caughtTotal = true, x.StartedAt, x.LastJoinAt, x.InvitesPaused, x.CaughtTotal
+		r.mu.Unlock()
+	}
+}
+
+func (e *Engine) startRaid(ctx context.Context, guildID string, s *securityrepo.Settings, joins int) {
+	e.event(ctx, guildID, securityrepo.EventRaidStarted, e.botID, "", fmt.Sprintf("%d joins in %ds", joins, s.RaidJoinSeconds))
+
+	paused := false
+	if s.RaidPauseInvites {
+		if err := e.setInvitesPaused(guildID, true); err != nil {
+			log.Printf("security: pausing invites in guild %s: %v", guildID, err)
+		} else {
+			paused = true
+			r := e.raidFor(guildID)
+			r.mu.Lock()
+			r.pausedInvites = true
+			r.mu.Unlock()
+		}
+	}
+
+	e.persistRaid(ctx, guildID, e.raidFor(guildID))
+
+	what := map[string]string{
+		securityrepo.ActionAlert: "nobody is being removed (alert only)", securityrepo.ActionTimeout: "raiders are being timed out",
+		securityrepo.ActionKick: "raiders are being kicked", securityrepo.ActionBan: "raiders are being banned",
+	}[s.RaidAction]
+	desc := fmt.Sprintf("%d members joined within %d seconds. Raid mode is on: %s.", joins, s.RaidJoinSeconds, what)
+	if paused {
+		desc += "\nInvites are paused until the raid ends."
+	}
+	desc += fmt.Sprintf("\nIt ends after %d minutes without a join, or with the button below (owner or trusted only).", s.RaidQuietMinutes)
+	e.send(ctx, guildID, s, alert{
+		ping: true, critical: true,
+		embed: &discordgo.MessageEmbed{
+			Title: "🚨 Raid detected", Description: desc, Color: colorAlert,
+			Timestamp: e.now().UTC().Format(time.RFC3339),
+		},
+		components: []discordgo.MessageComponent{discordgo.ActionsRow{Components: []discordgo.MessageComponent{
+			discordgo.Button{Label: "End raid", Style: discordgo.SecondaryButton, CustomID: CustomIDEndRaid},
+		}}},
+	})
+}
+
+// EndRaid turns raid mode off. by is who ended it ("" for the quiet timer).
+// Ending a raid relaxes protection, so callers must check the actor first.
+func (e *Engine) EndRaid(ctx context.Context, guildID, by string) error {
+	e.mu.Lock()
+	r, ok := e.raids[guildID]
+	e.mu.Unlock()
+	if !ok {
+		return UserError("There's no raid going on.")
+	}
+	r.mu.Lock()
+	if !r.active {
+		r.mu.Unlock()
+		return UserError("There's no raid going on.")
+	}
+	started, caught, total, paused := r.started, r.caught, r.caughtTotal, r.pausedInvites
+	r.active, r.caught, r.caughtTotal, r.pausedInvites, r.joins = false, nil, 0, false, nil
+	r.mu.Unlock()
+
+	if paused {
+		if err := e.setInvitesPaused(guildID, false); err != nil {
+			log.Printf("security: resuming invites in guild %s: %v", guildID, err)
+		}
+	}
+
+	how := "after a quiet period"
+	if by != "" {
+		how = "by <@" + by + ">"
+	}
+	e.event(ctx, guildID, securityrepo.EventRaidEnded, by, "", fmt.Sprintf("%d raiders caught", total))
+
+	// The database has the full list even across a restart; memory is the
+	// fallback if it can't be read.
+	if saved, err := e.st.ListRaidCaught(ctx, parseID(guildID), maxCaught); err == nil && len(saved) >= len(caught) {
+		caught = caught[:0]
+		for _, c := range saved {
+			caught = append(caught, caughtRec{userID: id(c.UserID), action: c.Action, name: c.Name})
+		}
+	}
+	if err := e.st.DeleteRaid(ctx, parseID(guildID)); err != nil {
+		log.Printf("security: clearing raid state for guild %s: %v", guildID, err)
+	}
+
+	var list strings.Builder
+	fmt.Fprintf(&list, "Raid from %s to %s (UTC)\n\n", started.UTC().Format("2006-01-02 15:04:05"), e.now().UTC().Format("15:04:05"))
+	for _, c := range caught {
+		fmt.Fprintf(&list, "%s\t%s\t%s\n", c.userID, c.action, c.name)
+	}
+	if total > len(caught) {
+		fmt.Fprintf(&list, "... and %d more\n", total-len(caught))
+	}
+	desc := fmt.Sprintf("Raid mode ended %s. %d accounts were caught; the list is attached.", how, total)
+	if paused {
+		desc += "\nInvites are open again."
+	}
+	if s, _, err := e.load(ctx, guildID); err == nil {
+		e.send(ctx, guildID, s, alert{
+			critical: true,
+			embed:    &discordgo.MessageEmbed{Title: "Raid over", Description: desc, Color: colorOK},
+			file:     textFile("raid-"+started.UTC().Format("20060102-1504")+".txt", list.String()),
+		})
+	}
+	return nil
+}
+
+// WatchRaids ends raids after their quiet period and frees memory for
+// servers that have gone quiet. It runs until ctx ends.
+func (e *Engine) WatchRaids(ctx context.Context, every time.Duration) {
+	t := time.NewTicker(every)
+	defer t.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-t.C:
+			e.checkRaids(ctx)
+		}
+	}
+}
+
+func (e *Engine) checkRaids(ctx context.Context) {
+	e.mu.Lock()
+	guilds := make([]string, 0, len(e.raids))
+	for g := range e.raids {
+		guilds = append(guilds, g)
+	}
+	e.mu.Unlock()
+
+	now := e.now()
+	for _, g := range guilds {
+		s, _, err := e.load(ctx, g)
+		if err != nil {
+			continue
+		}
+		r := e.raidFor(g)
+		r.mu.Lock()
+		active, last := r.active, r.lastJoin
+		r.mu.Unlock()
+		switch {
+		case active && now.Sub(last) >= time.Duration(s.RaidQuietMinutes)*time.Minute:
+			_ = e.EndRaid(ctx, g, "")
+		case !active && now.Sub(last) > 10*time.Minute:
+			e.mu.Lock()
+			delete(e.raids, g)
+			e.mu.Unlock()
+		}
+	}
+}
+
+// setInvitesPaused uses Discord's built-in "pause invites" (guild incident
+// actions). Paused for up to 24 hours, Discord's maximum; resumed when the
+// raid ends.
+func (e *Engine) setInvitesPaused(guildID string, paused bool) error {
+	body := map[string]any{"invites_disabled_until": nil}
+	if paused {
+		body["invites_disabled_until"] = e.now().Add(24 * time.Hour).UTC().Format(time.RFC3339)
+	}
+	url := discordgo.EndpointGuild(guildID) + "/incident-actions"
+	_, err := e.d.RequestWithBucketID("PUT", url, body, url)
+	return err
+}

internal/security/restore.go

@@ -0,0 +1,322 @@
+package security
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"sort"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Snapshots record a guild's roles and channels (names, settings,
+// permissions, channel permission overwrites) so a nuke can be undone.
+// Messages and who had which role can't be captured or brought back; Discord
+// offers no way to.
+const (
+	snapshotEvery    = 6 * time.Hour
+	snapshotCheckGap = 30 * time.Minute
+)
+
+type snapRole struct {
+	ID          string `json:"id"`
+	Name        string `json:"name"`
+	Color       int    `json:"color"`
+	Hoist       bool   `json:"hoist"`
+	Mentionable bool   `json:"mentionable"`
+	Permissions int64  `json:"permissions"`
+	Position    int    `json:"position"`
+}
+
+type snapOverwrite struct {
+	ID    string `json:"id"`
+	Type  int    `json:"type"`
+	Allow int64  `json:"allow"`
+	Deny  int64  `json:"deny"`
+}
+
+type snapChannel struct {
+	ID         string          `json:"id"`
+	Name       string          `json:"name"`
+	Type       int             `json:"type"`
+	Topic      string          `json:"topic,omitempty"`
+	ParentID   string          `json:"parent_id,omitempty"`
+	Position   int             `json:"position"`
+	NSFW       bool            `json:"nsfw,omitempty"`
+	RateLimit  int             `json:"rate_limit,omitempty"`
+	Bitrate    int             `json:"bitrate,omitempty"`
+	UserLimit  int             `json:"user_limit,omitempty"`
+	Overwrites []snapOverwrite `json:"overwrites,omitempty"`
+}
+
+type snapshotData struct {
+	Roles    []snapRole    `json:"roles"`
+	Channels []snapChannel `json:"channels"`
+}
+
+// restorable channel types: no threads, which belong to their parent.
+func restorable(t discordgo.ChannelType) bool {
+	switch t {
+	case discordgo.ChannelTypeGuildText, discordgo.ChannelTypeGuildVoice, discordgo.ChannelTypeGuildCategory,
+		discordgo.ChannelTypeGuildNews, discordgo.ChannelTypeGuildStageVoice, discordgo.ChannelTypeGuildForum:
+		return true
+	}
+	return false
+}
+
+// TakeSnapshot records the guild's current roles and channels.
+func (e *Engine) TakeSnapshot(ctx context.Context, guildID, by string) (roles, channels int, err error) {
+	rs, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return 0, 0, fmt.Errorf("listing roles: %w", err)
+	}
+	cs, err := e.d.GuildChannels(guildID)
+	if err != nil {
+		return 0, 0, fmt.Errorf("listing channels: %w", err)
+	}
+	var data snapshotData
+	for _, r := range rs {
+		if r.Managed {
+			continue // integration roles come back with their bot
+		}
+		data.Roles = append(data.Roles, snapRole{ID: r.ID, Name: r.Name, Color: r.Color, Hoist: r.Hoist,
+			Mentionable: r.Mentionable, Permissions: r.Permissions, Position: r.Position})
+	}
+	for _, c := range cs {
+		if !restorable(c.Type) {
+			continue
+		}
+		sc := snapChannel{ID: c.ID, Name: c.Name, Type: int(c.Type), Topic: c.Topic, ParentID: c.ParentID, Position: c.Position,
+			NSFW: c.NSFW, RateLimit: c.RateLimitPerUser, Bitrate: c.Bitrate, UserLimit: c.UserLimit}
+		for _, o := range c.PermissionOverwrites {
+			sc.Overwrites = append(sc.Overwrites, snapOverwrite{ID: o.ID, Type: int(o.Type), Allow: o.Allow, Deny: o.Deny})
+		}
+		data.Channels = append(data.Channels, sc)
+	}
+	raw, err := json.Marshal(data)
+	if err != nil {
+		return 0, 0, err
+	}
+	if err := e.st.SaveSnapshot(ctx, securityrepo.Snapshot{GuildID: parseID(guildID), Data: raw, Roles: len(data.Roles), Channels: len(data.Channels)}); err != nil {
+		return 0, 0, err
+	}
+	if by != "" {
+		e.event(ctx, guildID, securityrepo.EventSnapshot, by, "", fmt.Sprintf("%d roles, %d channels", len(data.Roles), len(data.Channels)))
+	}
+	return len(data.Roles), len(data.Channels), nil
+}
+
+// WatchSnapshots takes a snapshot of every guild with anti-nuke on whose
+// newest one is older than six hours. It runs until ctx ends.
+func (e *Engine) WatchSnapshots(ctx context.Context) {
+	run := func() {
+		due, err := e.st.GuildsDueForSnapshot(ctx, snapshotEvery)
+		if err != nil {
+			log.Printf("security: finding guilds due a snapshot: %v", err)
+			return
+		}
+		for _, g := range due {
+			if _, _, err := e.TakeSnapshot(ctx, id(g), ""); err != nil {
+				log.Printf("security: snapshot of guild %d: %v", g, err)
+			}
+		}
+	}
+	run()
+	t := time.NewTicker(snapshotCheckGap)
+	defer t.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-t.C:
+			run()
+		}
+	}
+}
+
+// RestoreResult says what a restore did.
+type RestoreResult struct {
+	RolesCreated, RolesReverted, ChannelsCreated, Failed int
+	SnapshotAt                                           time.Time
+}
+
+// Restore brings the guild back towards its latest snapshot:
+//
+//   - roles that are gone are recreated (same name, colour, permissions);
+//   - roles that gained Administrator, Manage Server, Manage Roles or Manage
+//     Webhooks since the snapshot get their snapshot permissions back;
+//   - channels that are gone are recreated, categories first, with their
+//     permission overwrites pointing at the recreated roles.
+//
+// Nothing is deleted: channels and roles made since the snapshot stay, since
+// some may be legitimate. Restoring rewrites the server, so callers must check
+// the actor is the owner or trusted. One restore per guild runs at a time.
+func (e *Engine) Restore(ctx context.Context, guildID, by string) (*RestoreResult, error) {
+	e.mu.Lock()
+	if e.restoring[guildID] {
+		e.mu.Unlock()
+		return nil, UserError("A restore is already running for this server.")
+	}
+	e.restoring[guildID] = true
+	e.mu.Unlock()
+	defer func() {
+		e.mu.Lock()
+		delete(e.restoring, guildID)
+		e.mu.Unlock()
+	}()
+
+	snap, err := e.st.LatestSnapshot(ctx, parseID(guildID))
+	if err != nil {
+		return nil, err
+	}
+	if snap == nil {
+		return nil, UserError("There's no snapshot to restore from yet. Turn anti-nuke on (snapshots are taken every 6 hours) or take one with `/security snapshot`.")
+	}
+	var data snapshotData
+	if err := json.Unmarshal(snap.Data, &data); err != nil {
+		return nil, fmt.Errorf("reading the snapshot: %w", err)
+	}
+	res := &RestoreResult{SnapshotAt: snap.CreatedAt}
+	reason := discordgo.WithAuditLogReason("Velox restore from snapshot")
+
+	// Roles.
+	current, err := e.d.GuildRoles(guildID)
+	if err != nil {
+		return nil, fmt.Errorf("listing roles: %w", err)
+	}
+	now := map[string]*discordgo.Role{}
+	for _, r := range current {
+		now[r.ID] = r
+	}
+	roleMap := map[string]string{} // snapshot role ID -> current role ID
+	sort.Slice(data.Roles, func(i, j int) bool { return data.Roles[i].Position < data.Roles[j].Position })
+	for _, sr := range data.Roles {
+		if cur, ok := now[sr.ID]; ok {
+			roleMap[sr.ID] = sr.ID
+			if added := cur.Permissions &^ sr.Permissions; added&DangerousPerms != 0 && !cur.Managed {
+				perms := sr.Permissions
+				if _, err := e.d.GuildRoleEdit(guildID, sr.ID, &discordgo.RoleParams{Permissions: &perms}, reason); err != nil {
+					log.Printf("security: restore: reverting role %s in guild %s: %v", sr.ID, guildID, err)
+					res.Failed++
+				} else {
+					res.RolesReverted++
+				}
+			}
+			continue
+		}
+		if sr.ID == guildID {
+			continue // @everyone always exists
+		}
+		color, hoist, mention, perms := sr.Color, sr.Hoist, sr.Mentionable, sr.Permissions
+		r, err := e.d.GuildRoleCreate(guildID, &discordgo.RoleParams{Name: sr.Name, Color: &color, Hoist: &hoist, Mentionable: &mention, Permissions: &perms}, reason)
+		if err != nil {
+			log.Printf("security: restore: recreating role %q in guild %s: %v", sr.Name, guildID, err)
+			res.Failed++
+			continue
+		}
+		roleMap[sr.ID] = r.ID
+		res.RolesCreated++
+	}
+
+	// Channels: categories first so the others can be put back in them.
+	chans, err := e.d.GuildChannels(guildID)
+	if err != nil {
+		return res, fmt.Errorf("listing channels: %w", err)
+	}
+	exists := map[string]bool{}
+	for _, c := range chans {
+		exists[c.ID] = true
+	}
+	chanMap := map[string]string{}
+	for _, c := range chans {
+		chanMap[c.ID] = c.ID
+	}
+	sort.SliceStable(data.Channels, func(i, j int) bool {
+		ci := data.Channels[i].Type == int(discordgo.ChannelTypeGuildCategory)
+		cj := data.Channels[j].Type == int(discordgo.ChannelTypeGuildCategory)
+		if ci != cj {
+			return ci
+		}
+		return data.Channels[i].Position < data.Channels[j].Position
+	})
+	for _, sc := range data.Channels {
+		if exists[sc.ID] {
+			continue
+		}
+		var overwrites []*discordgo.PermissionOverwrite
+		for _, o := range sc.Overwrites {
+			target := o.ID
+			if discordgo.PermissionOverwriteType(o.Type) == discordgo.PermissionOverwriteTypeRole {
+				mapped, ok := roleMap[o.ID]
+				if !ok {
+					continue // the role couldn't be brought back
+				}
+				target = mapped
+			}
+			overwrites = append(overwrites, &discordgo.PermissionOverwrite{ID: target, Type: discordgo.PermissionOverwriteType(o.Type), Allow: o.Allow, Deny: o.Deny})
+		}
+		parent := ""
+		if sc.ParentID != "" {
+			parent = chanMap[sc.ParentID] // "" if the category couldn't be restored
+		}
+		c, err := e.d.GuildChannelCreateComplex(guildID, discordgo.GuildChannelCreateData{
+			Name: sc.Name, Type: discordgo.ChannelType(sc.Type), Topic: sc.Topic, Bitrate: sc.Bitrate, UserLimit: sc.UserLimit,
+			RateLimitPerUser: sc.RateLimit, Position: sc.Position, PermissionOverwrites: overwrites, ParentID: parent, NSFW: sc.NSFW,
+		}, reason)
+		if err != nil {
+			log.Printf("security: restore: recreating channel %q in guild %s: %v", sc.Name, guildID, err)
+			res.Failed++
+			continue
+		}
+		chanMap[sc.ID] = c.ID
+		res.ChannelsCreated++
+	}
+
+	// Point the snapshot at the recreated roles and channels, so restoring
+	// again doesn't create them a second time. The content stays the
+	// snapshot's: nothing made since (or by an attacker) is added.
+	if res.RolesCreated+res.ChannelsCreated > 0 {
+		for i := range data.Roles {
+			if nid, ok := roleMap[data.Roles[i].ID]; ok {
+				data.Roles[i].ID = nid
+			}
+		}
+		for i := range data.Channels {
+			c := &data.Channels[i]
+			if nid, ok := chanMap[c.ID]; ok {
+				c.ID = nid
+			}
+			if nid, ok := chanMap[c.ParentID]; ok && c.ParentID != "" {
+				c.ParentID = nid
+			}
+			for j := range c.Overwrites {
+				if c.Overwrites[j].Type == int(discordgo.PermissionOverwriteTypeRole) {
+					if nid, ok := roleMap[c.Overwrites[j].ID]; ok {
+						c.Overwrites[j].ID = nid
+					}
+				}
+			}
+		}
+		if raw, err := json.Marshal(data); err == nil {
+			if err := e.st.SaveSnapshot(ctx, securityrepo.Snapshot{GuildID: parseID(guildID), Data: raw, Roles: snap.Roles, Channels: snap.Channels}); err != nil {
+				log.Printf("security: saving the remapped snapshot for guild %s: %v", guildID, err)
+			}
+		}
+	}
+
+	e.event(ctx, guildID, securityrepo.EventRestored, by, "", fmt.Sprintf("%d roles recreated, %d reverted, %d channels recreated, %d failed",
+		res.RolesCreated, res.RolesReverted, res.ChannelsCreated, res.Failed))
+	if s, _, err := e.load(ctx, guildID); err == nil {
+		e.send(ctx, guildID, s, alert{critical: true, embed: &discordgo.MessageEmbed{
+			Title: "♻️ Server restored from snapshot",
+			Description: fmt.Sprintf("Snapshot from <t:%d:f>. Recreated %d roles and %d channels, reverted dangerous permissions on %d roles. %d steps failed.\nMembers need their recreated roles given back by hand; Discord doesn't let bots see who had them.",
+				res.SnapshotAt.Unix(), res.RolesCreated, res.ChannelsCreated, res.RolesReverted, res.Failed),
+			Color: colorOK,
+		}})
+	}
+	return res, nil
+}

internal/security/security.go

@@ -0,0 +1,354 @@
+// Package security is the bot's anti-raid and anti-nuke system, modelled on
+// Wick:
+//
+//   - Join Gate: checks on every join (no avatar, new account, invite links
+//     or blocked words in the name, unverified bots), each with its own
+//     action, plus kicking bots added by anyone who isn't trusted.
+//   - Raid mode: a burst of joins starts it; raiders are timed out, kicked or
+//     banned, invites can be paused, staff are alerted, and it ends after a
+//     quiet period or when staff end it.
+//   - Anti-nuke: destructive actions (deleting channels or roles, mass bans
+//     and kicks, webhooks, dangerous permissions) are counted per person from
+//     the audit log; anyone who isn't the owner or trusted and goes over a
+//     limit is quarantined: roles removed and saved, timed out.
+//   - Lockdown: lock a channel, every channel, or joins, and unlock exactly
+//     back to how they were.
+//
+// Safety rules every entry point follows:
+//
+//   - Turning protection off, changing limits, releasing a quarantine and
+//     unlocking need the server owner or someone on the trusted list.
+//     Editing the trusted list needs the owner. Discord's command
+//     permissions are never relied on, since admins can change them.
+//   - The owner and the bot itself are never punished.
+//   - Configured roles are checked when used, not just when saved: a
+//     quarantine role that gained dangerous permissions is not assigned.
+//   - Messages only ever ping the configured alert role, and user-controlled
+//     text (names) is escaped.
+//   - Memory per server is bounded, and settings are cached briefly so a
+//     raid of thousands of joins doesn't turn into thousands of queries.
+package security
+
+import (
+	"context"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+// Store is the subset of securityrepo.Repo the system uses.
+type Store interface {
+	GetSettings(ctx context.Context, guildID int64) (*securityrepo.Settings, error)
+	SetEnabled(ctx context.Context, guildID int64, feature string, on bool) error
+	SetAlerts(ctx context.Context, guildID, channelID, roleID int64) error
+	SetQuarantineRole(ctx context.Context, guildID, roleID int64) error
+	SetJoinLock(ctx context.Context, guildID int64, mode string) error
+	ListTrusted(ctx context.Context, guildID int64) ([]securityrepo.Trusted, error)
+	AddTrusted(ctx context.Context, guildID int64, t securityrepo.Trusted) error
+	RemoveTrusted(ctx context.Context, guildID, targetID int64) (bool, error)
+	SaveQuarantine(ctx context.Context, q securityrepo.Quarantine) error
+	GetQuarantine(ctx context.Context, guildID, userID int64) (*securityrepo.Quarantine, error)
+	ListQuarantines(ctx context.Context, guildID int64) ([]securityrepo.Quarantine, error)
+	DeleteQuarantine(ctx context.Context, guildID, userID int64) error
+	SaveLockdown(ctx context.Context, l securityrepo.Lockdown) error
+	GetLockdown(ctx context.Context, guildID, channelID int64) (*securityrepo.Lockdown, error)
+	ListLockdowns(ctx context.Context, guildID int64, serverWideOnly bool) ([]securityrepo.Lockdown, error)
+	DeleteLockdown(ctx context.Context, guildID, channelID int64) error
+	AddEvent(ctx context.Context, e securityrepo.Event) error
+	ListUnprocessedCommands(ctx context.Context) ([]securityrepo.Command, error)
+	MarkCommandProcessed(ctx context.Context, id int64) error
+	SaveRaid(ctx context.Context, x securityrepo.Raid) error
+	ListRaids(ctx context.Context) ([]securityrepo.Raid, error)
+	DeleteRaid(ctx context.Context, guildID int64) error
+	AddRaidCaught(ctx context.Context, guildID int64, c securityrepo.Caught) error
+	ListRaidCaught(ctx context.Context, guildID int64, limit int) ([]securityrepo.Caught, error)
+	SaveSnapshot(ctx context.Context, s securityrepo.Snapshot) error
+	LatestSnapshot(ctx context.Context, guildID int64) (*securityrepo.Snapshot, error)
+	GuildsDueForSnapshot(ctx context.Context, maxAge time.Duration) ([]int64, error)
+}
+
+// Discord is the subset of *discordgo.Session the system uses.
+type Discord interface {
+	Guild(guildID string, options ...discordgo.RequestOption) (*discordgo.Guild, error)
+	UserChannelCreate(recipientID string, options ...discordgo.RequestOption) (*discordgo.Channel, error)
+	User(userID string, options ...discordgo.RequestOption) (*discordgo.User, error)
+	GuildRoles(guildID string, options ...discordgo.RequestOption) ([]*discordgo.Role, error)
+	GuildChannels(guildID string, options ...discordgo.RequestOption) ([]*discordgo.Channel, error)
+	GuildMember(guildID, userID string, options ...discordgo.RequestOption) (*discordgo.Member, error)
+	GuildMemberEdit(guildID, userID string, data *discordgo.GuildMemberParams, options ...discordgo.RequestOption) (*discordgo.Member, error)
+	GuildMemberTimeout(guildID, userID string, until *time.Time, options ...discordgo.RequestOption) error
+	GuildMemberDeleteWithReason(guildID, userID, reason string, options ...discordgo.RequestOption) error
+	GuildBanCreateWithReason(guildID, userID, reason string, days int, options ...discordgo.RequestOption) error
+	Channel(channelID string, options ...discordgo.RequestOption) (*discordgo.Channel, error)
+	ChannelPermissionSet(channelID, targetID string, targetType discordgo.PermissionOverwriteType, allow, deny int64, options ...discordgo.RequestOption) error
+	ChannelPermissionDelete(channelID, targetID string, options ...discordgo.RequestOption) error
+	ChannelMessageSendComplex(channelID string, data *discordgo.MessageSend, options ...discordgo.RequestOption) (*discordgo.Message, error)
+	RequestWithBucketID(method, urlStr string, data interface{}, bucketID string, options ...discordgo.RequestOption) ([]byte, error)
+	ChannelMessageDelete(channelID, messageID string, options ...discordgo.RequestOption) error
+	GuildRoleCreate(guildID string, data *discordgo.RoleParams, options ...discordgo.RequestOption) (*discordgo.Role, error)
+	GuildRoleEdit(guildID, roleID string, data *discordgo.RoleParams, options ...discordgo.RequestOption) (*discordgo.Role, error)
+	GuildChannelCreateComplex(guildID string, data discordgo.GuildChannelCreateData, options ...discordgo.RequestOption) (*discordgo.Channel, error)
+}
+
+// UserError is shown to the person who acted, as written.
+type UserError string
+
+func (e UserError) Error() string { return string(e) }
+
+const (
+	ErrNotTrusted = UserError("Only the server owner or someone on the security trusted list can do that.")
+	ErrNotOwner   = UserError("Only the server owner can change the trusted list.")
+)
+
+// Dangerous permissions: what a nuker needs, and what no quarantine or alert
+// role may have.
+const DangerousPerms = discordgo.PermissionAdministrator | discordgo.PermissionManageGuild |
+	discordgo.PermissionManageRoles | discordgo.PermissionManageWebhooks
+
+const (
+	timeoutJoin       = 24 * time.Hour
+	timeoutQuarantine = 28*24*time.Hour - time.Hour // Discord's maximum is 28 days
+	settingsTTL       = 15 * time.Second
+	ownerTTL          = 10 * time.Minute
+)
+
+// Engine holds the system's state. One per bot.
+type Engine struct {
+	d     Discord
+	st    Store
+	botID string
+	now   func() time.Time
+
+	mu        sync.Mutex
+	settings  map[string]cachedSettings
+	owners    map[string]cachedOwner
+	raids     map[string]*raid
+	nukes     *nukeCounter
+	roleCache map[string]cachedRoles
+	heat      map[string]*guildHeat
+	restoring map[string]bool
+
+	// syncDMs sends alert DMs before returning (tests); normally they go out
+	// in the background so an alert never waits on them.
+	syncDMs bool
+
+	// ChannelPerms reports a member's permissions in a channel from the
+	// gateway cache (no REST call), used to exempt moderators from heat.
+	// Nil means nobody is exempt by permission.
+	ChannelPerms func(userID, channelID string) (int64, error)
+}
+
+type cachedSettings struct {
+	s       *securityrepo.Settings
+	trusted []securityrepo.Trusted
+	at      time.Time
+}
+
+type cachedOwner struct {
+	id   string
+	name string
+	at   time.Time
+}
+
+func New(d Discord, st Store, botID string) *Engine {
+	return &Engine{
+		d: d, st: st, botID: botID, now: time.Now,
+		settings:  map[string]cachedSettings{},
+		owners:    map[string]cachedOwner{},
+		raids:     map[string]*raid{},
+		nukes:     newNukeCounter(),
+		heat:      map[string]*guildHeat{},
+		restoring: map[string]bool{},
+	}
+}
+
+var (
+	defaultEngine *Engine
+	pendingStore  Store
+)
+
+// Configure sets the store; Start creates the engine once the bot knows its
+// own user ID (after the gateway connects).
+func Configure(st Store) { pendingStore = st }
+
+// Start creates the default engine for a connected session. It returns nil
+// when no store was configured.
+func Start(d Discord, botID string) *Engine {
+	if pendingStore == nil {
+		return nil
+	}
+	defaultEngine = New(d, pendingStore, botID)
+	return defaultEngine
+}
+
+func Init(e *Engine) { defaultEngine = e }
+
+func Default() *Engine { return defaultEngine }
+
+func parseID(s string) int64 {
+	n, _ := strconv.ParseInt(s, 10, 64)
+	return n
+}
+
+func id(n int64) string { return strconv.FormatInt(n, 10) }
+
+// load returns the guild's settings and trusted list, cached briefly.
+func (e *Engine) load(ctx context.Context, guildID string) (*securityrepo.Settings, []securityrepo.Trusted, error) {
+	e.mu.Lock()
+	c, ok := e.settings[guildID]
+	e.mu.Unlock()
+	if ok && e.now().Sub(c.at) < settingsTTL {
+		return c.s, c.trusted, nil
+	}
+	g := parseID(guildID)
+	s, err := e.st.GetSettings(ctx, g)
+	if err != nil {
+		return nil, nil, err
+	}
+	trusted, err := e.st.ListTrusted(ctx, g)
+	if err != nil {
+		return nil, nil, err
+	}
+	e.mu.Lock()
+	e.settings[guildID] = cachedSettings{s: s, trusted: trusted, at: e.now()}
+	e.mu.Unlock()
+	return s, trusted, nil
+}
+
+// Invalidate drops the cached settings after a change, so it applies at once.
+func (e *Engine) Invalidate(guildID string) {
+	e.mu.Lock()
+	delete(e.settings, guildID)
+	e.mu.Unlock()
+}
+
+// Settings returns the current settings (for status displays).
+func (e *Engine) Settings(ctx context.Context, guildID string) (*securityrepo.Settings, []securityrepo.Trusted, error) {
+	return e.load(ctx, guildID)
+}
+
+// OwnerID returns the guild owner's ID, cached.
+func (e *Engine) OwnerID(guildID string) (string, error) {
+	e.mu.Lock()
+	c, ok := e.owners[guildID]
+	e.mu.Unlock()
+	if ok && e.now().Sub(c.at) < ownerTTL {
+		return c.id, nil
+	}
+	g, err := e.d.Guild(guildID)
+	if err != nil {
+		return "", err
+	}
+	e.mu.Lock()
+	e.owners[guildID] = cachedOwner{id: g.OwnerID, name: g.Name, at: e.now()}
+	e.mu.Unlock()
+	return g.OwnerID, nil
+}
+
+// guildName returns the guild's name (cached with the owner), or "".
+func (e *Engine) guildName(guildID string) string {
+	if _, err := e.OwnerID(guildID); err != nil {
+		return ""
+	}
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	return e.owners[guildID].name
+}
+
+// trustedBy reports whether a user (with their role IDs) is on the list.
+func trustedBy(list []securityrepo.Trusted, userID string, roles []string) bool {
+	uid := parseID(userID)
+	for _, t := range list {
+		switch t.Kind {
+		case "user":
+			if t.TargetID == uid {
+				return true
+			}
+		case "role":
+			for _, r := range roles {
+				if parseID(r) == t.TargetID {
+					return true
+				}
+			}
+		}
+	}
+	return false
+}
+
+// IsTrusted reports whether a user is exempt from anti-nuke and may change
+// security settings: the owner, the bot itself, or someone on the trusted
+// list (directly or by role). When roles is nil the member is looked up.
+// Any lookup failure counts as not trusted.
+func (e *Engine) IsTrusted(ctx context.Context, guildID, userID string, roles []string) bool {
+	if userID == "" {
+		return false
+	}
+	if userID == e.botID {
+		return true
+	}
+	if owner, err := e.OwnerID(guildID); err == nil && owner == userID {
+		return true
+	}
+	_, trusted, err := e.load(ctx, guildID)
+	if err != nil {
+		return false
+	}
+	if roles == nil {
+		m, err := e.d.GuildMember(guildID, userID)
+		if err != nil {
+			return trustedBy(trusted, userID, nil)
+		}
+		roles = m.Roles
+	}
+	return trustedBy(trusted, userID, roles)
+}
+
+// IsOwner reports whether the user owns the guild. Lookup failures are "no".
+func (e *Engine) IsOwner(guildID, userID string) bool {
+	owner, err := e.OwnerID(guildID)
+	return err == nil && owner != "" && owner == userID
+}
+
+// RequireTrusted returns ErrNotTrusted unless the actor is owner or trusted.
+func (e *Engine) RequireTrusted(ctx context.Context, guildID string, actor *discordgo.Member) error {
+	if actor == nil || actor.User == nil || !e.IsTrusted(ctx, guildID, actor.User.ID, actor.Roles) {
+		return ErrNotTrusted
+	}
+	return nil
+}
+
+func (e *Engine) event(ctx context.Context, guildID string, kind string, actor, target string, detail string) {
+	_ = e.st.AddEvent(ctx, securityrepo.Event{
+		GuildID: parseID(guildID), Kind: kind, ActorID: parseID(actor), TargetID: parseID(target), Detail: clip(detail, 1000),
+	})
+}
+
+func clip(s string, n int) string {
+	if r := []rune(s); len(r) > n {
+		return string(r[:n-1]) + "…"
+	}
+	return s
+}
+
+// safeName renders a user-controlled name for an embed: markdown escaped and
+// mentions defused (allowed mentions are restricted too, this is belt and
+// braces).
+func safeName(u *discordgo.User) string {
+	if u == nil {
+		return "unknown"
+	}
+	name := u.Username
+	if u.GlobalName != "" && u.GlobalName != u.Username {
+		name = u.GlobalName + " (" + u.Username + ")"
+	}
+	r := strings.NewReplacer(
+		`\`, `\\`, `*`, `\*`, `_`, `\_`, "`", "\\`", `~`, `\~`, `|`, `\|`, `>`, `\>`, `#`, `\#`,
+		`[`, `\[`, `]`, `\]`, `(`, `\(`, `)`, `\)`, `@`, "@​", `<`, "<​",
+	)
+	return clip(r.Replace(name), 80)
+}

internal/security/security_test.go

@@ -0,0 +1,594 @@
+package security
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	"velox-bot/internal/db/repos/securityrepo"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+var ctx = context.Background()
+
+// testEngine is a guild (id 100) owned by user 1, with Velox as user 999,
+// alerts going to channel 500 and pinging role 201.
+func testEngine(t *testing.T) (*Engine, *fakeDiscord, *fakeStore, *time.Time) {
+	t.Helper()
+	d, st := newDiscord(), newStore()
+	e := New(d, st, "999")
+	e.syncDMs = true
+	now := time.Date(2026, 10, 20, 12, 0, 0, 0, time.UTC)
+	e.now = func() time.Time { return now }
+	s := st.set(100)
+	s.AlertChannelID, s.AlertRoleID = 500, 201
+	return e, d, st, &now
+}
+
+func refresh(e *Engine) { e.Invalidate(guild) }
+
+// snowflake for an account created at t.
+func snowflakeAt(t time.Time, n int) string {
+	ms := t.UnixMilli() - 1420070400000
+	return fmt.Sprint(ms<<22 | int64(n))
+}
+
+func entry(action discordgo.AuditLogAction, user, target string, changes ...*discordgo.AuditLogChange) *discordgo.AuditLogEntry {
+	return &discordgo.AuditLogEntry{ActionType: &action, UserID: user, TargetID: target, Changes: changes}
+}
+
+func change(key discordgo.AuditLogChangeKey, old, new any) *discordgo.AuditLogChange {
+	return &discordgo.AuditLogChange{Key: &key, OldValue: old, NewValue: new}
+}
+
+func contains(list []string, v string) bool {
+	for _, x := range list {
+		if x == v {
+			return true
+		}
+	}
+	return false
+}
+
+// ---- Join Gate ----
+
+func TestCheckJoin(t *testing.T) {
+	now := time.Date(2026, 10, 20, 12, 0, 0, 0, time.UTC)
+	s := securityrepo.Defaults(1)
+	s.JoinGateEnabled = true
+	s.NoAvatar, s.NewAccount, s.AdvertisingName = securityrepo.ActionTimeout, securityrepo.ActionKick, securityrepo.ActionBan
+	s.UsernameFilter, s.UsernamePatterns = securityrepo.ActionKick, []string{" FreeNitro "}
+	s.UnverifiedBot = securityrepo.ActionKick
+
+	old := snowflakeAt(now.AddDate(-1, 0, 0), 1)
+	young := snowflakeAt(now.Add(-48*time.Hour), 2)
+
+	for _, c := range []struct {
+		name string
+		u    *discordgo.User
+		want string
+	}{
+		{"clean", &discordgo.User{ID: old, Username: "ana", Avatar: "x"}, "off"},
+		{"no avatar", &discordgo.User{ID: old, Username: "ana"}, "timeout"},
+		{"new account beats no avatar", &discordgo.User{ID: young, Username: "ana"}, "kick"},
+		{"invite in display name", &discordgo.User{ID: old, Username: "ana", GlobalName: "join DISCORD.GG/abc", Avatar: "x"}, "ban"},
+		{"blocked word, case-insensitive", &discordgo.User{ID: old, Username: "freenitro_giveaway", Avatar: "x"}, "kick"},
+		{"verified bot passes", &discordgo.User{ID: young, Bot: true, PublicFlags: discordgo.UserFlagVerifiedBot}, "off"},
+		{"unverified bot", &discordgo.User{ID: young, Bot: true}, "kick"},
+	} {
+		if got := CheckJoin(s, c.u, now).Action; got != c.want {
+			t.Errorf("%s: got %s, want %s", c.name, got, c.want)
+		}
+	}
+	s.JoinGateEnabled = false
+	if CheckJoin(s, &discordgo.User{ID: young}, now).Action != "off" {
+		t.Error("a disabled Join Gate must not act")
+	}
+}
+
+func TestJoinGateAndJoinLock(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.JoinGateEnabled, s.NewAccount = true, securityrepo.ActionKick
+	refresh(e)
+
+	young := d.addMember(snowflakeAt(now.Add(-time.Hour), 5))
+	if removed := e.OnMemberJoin(ctx, guild, young); !removed || !contains(d.kicked, young.User.ID) {
+		t.Errorf("new account should be kicked: removed=%v kicked=%v", removed, d.kicked)
+	}
+	if d.sentCount() != 1 || !contains(st.eventKinds(), securityrepo.EventJoinGate) {
+		t.Error("the action should be alerted and recorded")
+	}
+
+	st.set(100).JoinLock = securityrepo.ActionBan
+	refresh(e)
+	m := d.addMember(snowflakeAt(now.AddDate(-2, 0, 0), 6))
+	if !e.OnMemberJoin(ctx, guild, m) || !contains(d.banned, m.User.ID) {
+		t.Error("a join lock bans everyone new")
+	}
+}
+
+func TestOwnerAndBotAreNeverPunished(t *testing.T) {
+	e, d, st, _ := testEngine(t)
+	st.set(100).JoinLock = securityrepo.ActionBan
+	refresh(e)
+	if e.OnMemberJoin(ctx, guild, d.members["1"]) || len(d.banned) != 0 {
+		t.Error("the owner must never be banned")
+	}
+	if err := e.Quarantine(ctx, guild, "1", "x"); err == nil {
+		t.Error("the owner must never be quarantined")
+	}
+	if err := e.Quarantine(ctx, guild, "999", "x"); err == nil {
+		t.Error("the bot must never quarantine itself")
+	}
+}
+
+// ---- Raids ----
+
+func TestRaidModeStartsActsAndEnds(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.AntiRaidEnabled, s.RaidJoinCount, s.RaidJoinSeconds, s.RaidAction, s.RaidQuietMinutes = true, 3, 10, securityrepo.ActionKick, 5
+	refresh(e)
+
+	old := now.AddDate(-1, 0, 0)
+	join := func(n int) *discordgo.Member {
+		m := d.addMember(snowflakeAt(old, n))
+		e.OnMemberJoin(ctx, guild, m)
+		return m
+	}
+	a := join(1)
+	*now = now.Add(2 * time.Second)
+	join(2)
+	if len(d.kicked) != 0 || e.RaidActive(guild) {
+		t.Fatal("two joins are not a raid")
+	}
+	*now = now.Add(2 * time.Second)
+	join(3)
+	if !e.RaidActive(guild) || len(d.kicked) != 3 || !contains(d.kicked, a.User.ID) {
+		t.Fatalf("the third join starts a raid and the whole burst is kicked: %v", d.kicked)
+	}
+	if len(d.requests) != 1 || !strings.Contains(d.requests[0], "/incident-actions") || !strings.Contains(d.requests[0], "2026-10-21") {
+		t.Errorf("invites should be paused for 24h: %v", d.requests)
+	}
+	alert := d.channelSends()[0]
+	if alert.Content != "<@&201>" || strings.Join(alert.AllowedMentions.Roles, ",") != "201" || len(alert.AllowedMentions.Users) != 0 {
+		t.Errorf("a raid pings only the alert role: %+v", alert)
+	}
+
+	// During the raid every join is acted on.
+	*now = now.Add(time.Minute)
+	join(4)
+	if len(d.kicked) != 4 {
+		t.Errorf("joins during a raid are kicked: %v", d.kicked)
+	}
+
+	// Quiet for 5 minutes: it ends, invites resume, the list is posted.
+	*now = now.Add(6 * time.Minute)
+	e.checkRaids(ctx)
+	if e.RaidActive(guild) {
+		t.Fatal("the raid should end after the quiet period")
+	}
+	if len(d.requests) != 2 || !strings.Contains(d.requests[1], "invites_disabled_until:<nil>") {
+		t.Errorf("invites should be resumed: %v", d.requests)
+	}
+	var list string
+	for name, content := range d.files {
+		if strings.HasPrefix(name, "raid-") {
+			list = content
+		}
+	}
+	if strings.Count(list, "\tkick\t") != 4 {
+		t.Errorf("the summary should list the 4 kicked accounts:\n%s", list)
+	}
+	if err := e.EndRaid(ctx, guild, "1"); err == nil {
+		t.Error("ending twice should say there's no raid")
+	}
+}
+
+func TestNoAlertFloodDuringARaid(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.JoinGateEnabled, s.NoAvatar = true, securityrepo.ActionKick
+	s.AntiRaidEnabled, s.RaidJoinCount, s.RaidAction, s.RaidPauseInvites = true, 3, securityrepo.ActionKick, false
+	refresh(e)
+	for i := 0; i < 50; i++ {
+		e.OnMemberJoin(ctx, guild, &discordgo.Member{User: &discordgo.User{ID: snowflakeAt(now.AddDate(-1, 0, 0), i)}}) // no avatar
+	}
+	if n := d.sentCount(); n > 4 {
+		t.Errorf("a raid of 50 should produce a handful of alerts, got %d", n)
+	}
+}
+
+func TestRaidAlertOnlyTouchesNobody(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.AntiRaidEnabled, s.RaidJoinCount, s.RaidAction, s.RaidPauseInvites = true, 3, securityrepo.ActionAlert, false
+	refresh(e)
+	for i := 0; i < 5; i++ {
+		e.OnMemberJoin(ctx, guild, d.addMember(snowflakeAt(now.AddDate(-1, 0, 0), i)))
+	}
+	if !e.RaidActive(guild) || len(d.kicked)+len(d.banned) != 0 || len(d.requests) != 0 {
+		t.Error("alert-only raid mode must not remove anyone or pause invites")
+	}
+}
+
+func TestRaidMemoryIsBounded(t *testing.T) {
+	e, d, st, now := testEngine(t)
+	s := st.set(100)
+	s.AntiRaidEnabled, s.RaidJoinCount, s.RaidAction = true, 3, securityrepo.ActionAlert
+	refresh(e)
+	for i := 0; i < maxRecentJoins+300; i++ {
+		e.OnMemberJoin(ctx, guild, &discordgo.Member{User: &discordgo.User{ID: snowflakeAt(now.AddDate(-1, 0, 0), i), Avatar: "a"}})
+	}
+	r := e.raidFor(guild)
+	if len(r.joins) > maxRecentJoins {
+		t.Errorf("recent joins not capped: %d", len(r.joins))
+	}
+	_ = d
+}
+
+// ---- Anti-nuke ----
+
+func nukeEngine(t *testing.T) (*Engine, *fakeDiscord, *fakeStore) {
+	e, d, st, _ := testEngine(t)
+	st.set(100).AntiNukeEnabled = true
+	refresh(e)
+	d.addMember("50", "200", "202", "204") // a rogue admin with a booster role
+	return e, d, st
+}
+
+func TestNukeOverTheLimitIsQuarantined(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	// Limit is 2 channel deletes per 10s.
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionChannelDelete, "50", "c1"))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionChannelDelete, "50", "c2"))
+	if _, ok := st.quarantines[key(100, 50)]; ok {
+		t.Fatal("two deletes are within the limit")
+	}
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionChannelDelete, "50", "c3"))
+
+	q, ok := st.quarantines[key(100, 50)]
+	if !ok || fmt.Sprint(q.PreviousRoleIDs) != "[200 202]" {
+		t.Fatalf("roles should be saved (not the managed one): %+v", q)
+	}
+	if got := strings.Join(d.members["50"].Roles, ","); got != "204" {
+		t.Errorf("only the unremovable booster role should remain, got %s", got)
+	}
+	if d.timeouts["50"] == nil {
+		t.Error("the nuker should be timed out")
+	}
+	sends := d.channelSends()
+	last := sends[len(sends)-1]
+	if !strings.Contains(last.Embeds[0].Title, "Nuke attempt stopped") || !contains(last.AllowedMentions.Users, "1") {
+		t.Errorf("the owner should be pinged: %+v", last)
+	}
+
+	// The next delete within a minute doesn't trigger a second response.
+	before := len(d.sent)
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionChannelDelete, "50", "c4"))
+	if len(d.sent) != before {
+		t.Error("one attempt should be answered once")
+	}
+}
+
+func TestTrustedOwnerAndBotAreExempt(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	d.addMember("60", "201")
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 50, Kind: "user"}, {TargetID: 201, Kind: "role"}}
+	refresh(e)
+	for _, who := range []string{"50", "60", "1", "999"} {
+		for i := 0; i < 5; i++ {
+			e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberBanAdd, who, "x"))
+		}
+	}
+	if len(st.quarantines) != 0 {
+		t.Errorf("trusted users, trusted roles, the owner and the bot are exempt: %v", st.quarantines)
+	}
+}
+
+func TestInstantTriggers(t *testing.T) {
+	for name, ent := range map[string]*discordgo.AuditLogEntry{
+		"prune":   entry(discordgo.AuditLogActionMemberPrune, "50", ""),
+		"vanity":  entry(discordgo.AuditLogActionGuildUpdate, "50", guild, change("vanity_url_code", "old", "scam")),
+		"perms":   entry(discordgo.AuditLogActionRoleUpdate, "50", "202", change("permissions", "0", fmt.Sprint(discordgo.PermissionAdministrator))),
+		"grant":   entry(discordgo.AuditLogActionMemberRoleUpdate, "50", "70", change("$add", nil, []any{map[string]any{"id": "200"}})),
+		"newrole": entry(discordgo.AuditLogActionRoleCreate, "50", "x", change("permissions", nil, fmt.Sprint(discordgo.PermissionManageRoles))),
+		"botrole": entry(discordgo.AuditLogActionRoleUpdate, "50", "299", change("name", "Velox", "x")),
+	} {
+		t.Run(name, func(t *testing.T) {
+			e, d, st := nukeEngine(t)
+			d.addMember("70")
+			e.OnAuditLogEntry(ctx, guild, ent)
+			if _, ok := st.quarantines[key(100, 50)]; !ok {
+				t.Errorf("%s should quarantine at once", name)
+			}
+		})
+	}
+}
+
+func TestHarmlessChangesAreIgnored(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	d.addMember("70")
+	// Renaming a role, removing permissions, giving a plain role.
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionRoleUpdate, "50", "202", change("permissions", fmt.Sprint(discordgo.PermissionAdministrator), "0")))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberRoleUpdate, "50", "70", change("$add", nil, []any{map[string]any{"id": "202"}})))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionChannelUpdate, "50", "c"))
+	if len(st.quarantines) != 0 {
+		t.Error("harmless changes must not trigger anything")
+	}
+}
+
+func TestHarmlessEntriesCostNoLookups(t *testing.T) {
+	e, d, _ := nukeEngine(t)
+	d.lookups = 0
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMessageDelete, "50", "x"))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberUpdate, "50", "x"))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberRoleUpdate, "50", "70", change("$remove", nil, []any{map[string]any{"id": "202"}})))
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionGuildUpdate, "50", guild, change("name", "a", "b")))
+	if d.lookups != 0 {
+		t.Errorf("harmless entries made %d Discord lookups", d.lookups)
+	}
+}
+
+func TestSelfGrantedTrustedRoleIsNotABypass(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 201, Kind: "role"}}
+	refresh(e)
+	// The rogue admin gives themselves the trusted role...
+	d.members["50"].Roles = append(d.members["50"].Roles, "201")
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberRoleUpdate, "50", "50", change("$add", nil, []any{map[string]any{"id": "201"}})))
+	if _, ok := st.quarantines[key(100, 50)]; !ok {
+		t.Fatal("granting yourself a trusted role must be stopped, not count as trust")
+	}
+	if contains(d.members["50"].Roles, "201") {
+		t.Error("the trusted role should be gone")
+	}
+}
+
+func TestTrustedRoleGrantedToAnAltIsTakenBack(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 201, Kind: "role"}}
+	refresh(e)
+	d.addMember("71", "201")
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberRoleUpdate, "50", "71", change("$add", nil, []any{map[string]any{"id": "201"}})))
+	if _, ok := st.quarantines[key(100, 50)]; !ok {
+		t.Error("the granter should be quarantined")
+	}
+	if contains(d.members["71"].Roles, "201") {
+		t.Error("the alt should lose the trusted role")
+	}
+}
+
+func TestNukingBotIsKicked(t *testing.T) {
+	e, d, _ := nukeEngine(t)
+	d.members["80"] = &discordgo.Member{User: &discordgo.User{ID: "80", Bot: true}}
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "80", ""))
+	if !contains(d.kicked, "80") {
+		t.Error("a nuking bot should be kicked")
+	}
+}
+
+func TestAntiNukeOffDoesNothing(t *testing.T) {
+	e, _, st := nukeEngine(t)
+	st.set(100).AntiNukeEnabled = false
+	refresh(e)
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+	if len(st.quarantines) != 0 {
+		t.Error("anti-nuke off must not act")
+	}
+}
+
+func TestUnauthorizedBotAdd(t *testing.T) {
+	e, d, st, _ := testEngine(t)
+	st.set(100).JoinGateEnabled = true
+	refresh(e)
+	d.addMember("50", "200")
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionBotAdd, "50", "81"))
+	if !contains(d.kicked, "81") {
+		t.Error("a bot added by someone untrusted should be kicked")
+	}
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionBotAdd, "1", "82"))
+	if contains(d.kicked, "82") {
+		t.Error("the owner may add bots")
+	}
+}
+
+func TestDangerousQuarantineRoleIsNotAssigned(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.set(100).QuarantineRoleID = 200 // misconfigured: the Admin role
+	refresh(e)
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+	if contains(d.members["50"].Roles, "200") {
+		t.Error("a quarantine role with dangerous permissions must never be assigned")
+	}
+
+	st.set(100).QuarantineRoleID = 203
+	refresh(e)
+	d.addMember("51", "201")
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "51", ""))
+	if !contains(d.members["51"].Roles, "203") {
+		t.Error("a safe quarantine role should be assigned")
+	}
+}
+
+func TestQuarantineRoleVeloxCantAssignDoesNotBlockQuarantine(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.set(100).QuarantineRoleID = 203
+	refresh(e)
+	d.rejectRole = "203" // e.g. moved above Velox's role after it was configured
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+	if got := strings.Join(d.members["50"].Roles, ","); got != "204" {
+		t.Errorf("roles must still be removed without the quarantine role, got %s", got)
+	}
+	if d.timeouts["50"] == nil {
+		t.Error("and the member still timed out")
+	}
+}
+
+func TestReleaseGivesRolesBack(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	st.set(100).QuarantineRoleID = 203
+	refresh(e)
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+
+	// The Mod role was deleted meanwhile... no wait, Member (202) was.
+	d.roles = append(d.roles[:3], d.roles[4:]...)
+	if err := e.Release(ctx, guild, "50", "1"); err != nil {
+		t.Fatal(err)
+	}
+	got := strings.Join(d.members["50"].Roles, ",")
+	if got != "204,200" {
+		t.Errorf("roles after release = %s (want the booster role kept, Admin back, deleted Member skipped, quarantine role gone)", got)
+	}
+	if d.timeouts["50"] != nil {
+		t.Error("the timeout should be removed")
+	}
+	if _, ok := st.quarantines[key(100, 50)]; ok {
+		t.Error("the quarantine record should be gone")
+	}
+	if err := e.Release(ctx, guild, "50", "1"); err == nil {
+		t.Error("releasing twice should fail")
+	}
+}
+
+// ---- Lockdown ----
+
+func TestLockAndUnlockRestoreExactly(t *testing.T) {
+	e, d, _, _ := testEngine(t)
+	d.channels["300"] = &discordgo.Channel{ID: "300", GuildID: guild, Type: discordgo.ChannelTypeGuildText,
+		PermissionOverwrites: []*discordgo.PermissionOverwrite{{ID: guild, Type: discordgo.PermissionOverwriteTypeRole,
+			Allow: discordgo.PermissionAddReactions, Deny: discordgo.PermissionAttachFiles}}}
+	d.channels["301"] = &discordgo.Channel{ID: "301", GuildID: guild, Type: discordgo.ChannelTypeGuildText}
+	d.channels["302"] = &discordgo.Channel{ID: "302", GuildID: guild, Type: discordgo.ChannelTypeGuildCategory}
+	d.channels["400"] = &discordgo.Channel{ID: "400", GuildID: "other", Type: discordgo.ChannelTypeGuildText}
+
+	if err := e.LockChannel(ctx, guild, "400", "1", false); err == nil {
+		t.Fatal("a channel of another server must never be touched")
+	}
+
+	locked, failed, err := e.LockServer(ctx, guild, "1")
+	if err != nil || locked != 2 || failed != 0 {
+		t.Fatalf("locked=%d failed=%d err=%v (categories are skipped)", locked, failed, err)
+	}
+	o := d.channels["300"].PermissionOverwrites[0]
+	if o.Deny&discordgo.PermissionSendMessages == 0 || o.Allow&discordgo.PermissionAddReactions != 0 || o.Deny&discordgo.PermissionAttachFiles == 0 {
+		t.Errorf("lock should deny chat and keep other bits: %+v", o)
+	}
+	// Someone changes an unrelated bit during the lockdown; it must survive.
+	o.Allow |= discordgo.PermissionEmbedLinks
+	// Locking again must not overwrite the saved "before" state.
+	_ = e.LockChannel(ctx, guild, "300", "1", false)
+
+	if _, _, err := e.UnlockServer(ctx, guild, "1"); err != nil {
+		t.Fatal(err)
+	}
+	o = d.channels["300"].PermissionOverwrites[0]
+	if o.Allow != discordgo.PermissionAddReactions|discordgo.PermissionEmbedLinks || o.Deny != discordgo.PermissionAttachFiles {
+		t.Errorf("unlock should restore the original lock bits and keep the new one: allow=%d deny=%d", o.Allow, o.Deny)
+	}
+	if len(d.channels["301"].PermissionOverwrites) != 0 {
+		t.Error("a channel that had no overwrite should have none again")
+	}
+	if _, _, err := e.UnlockServer(ctx, guild, "1"); err == nil {
+		t.Error("unlocking an unlocked server should say so")
+	}
+}
+
+// ---- Configuration rules ----
+
+func TestConfigurationPermissions(t *testing.T) {
+	e, d, st, _ := testEngine(t)
+	admin := d.addMember("50", "200")
+	owner := d.members["1"]
+	trustedUser := d.addMember("60")
+	st.trusted[100] = []securityrepo.Trusted{{TargetID: 60, Kind: "user"}}
+	refresh(e)
+
+	// Turning on: Manage Server is enough. Turning off: owner or trusted only.
+	if err := e.SetFeature(ctx, guild, admin, discordgo.PermissionManageGuild, securityrepo.FeatureAntiNuke, true); err != nil {
+		t.Errorf("an admin may turn anti-nuke on: %v", err)
+	}
+	if err := e.SetFeature(ctx, guild, admin, discordgo.PermissionAdministrator, securityrepo.FeatureAntiNuke, false); !errors.Is(err, ErrNotTrusted) {
+		t.Errorf("an untrusted admin must not turn anti-nuke off: %v", err)
+	}
+	if err := e.SetFeature(ctx, guild, trustedUser, 0, securityrepo.FeatureAntiNuke, false); err != nil {
+		t.Errorf("a trusted user may: %v", err)
+	}
+	if err := e.SetFeature(ctx, guild, d.addMember("61"), 0, securityrepo.FeatureJoinGate, true); err == nil {
+		t.Error("a regular member must not turn things on")
+	}
+	if err := e.SetFeature(ctx, guild, nil, discordgo.PermissionAdministrator, securityrepo.FeatureJoinGate, true); err == nil {
+		t.Error("no actor, no change")
+	}
+
+	// Alerts: trusted only, never @everyone, only this server's channels.
+	d.channels["500"] = &discordgo.Channel{ID: "500", GuildID: guild, Type: discordgo.ChannelTypeGuildText}
+	d.channels["501"] = &discordgo.Channel{ID: "501", GuildID: "other", Type: discordgo.ChannelTypeGuildText}
+	if err := e.SetAlerts(ctx, guild, admin, "500", "201"); !errors.Is(err, ErrNotTrusted) {
+		t.Errorf("untrusted alert change: %v", err)
+	}
+	if err := e.SetAlerts(ctx, guild, owner, "500", guild); err == nil {
+		t.Error("alerts must never ping @everyone")
+	}
+	if err := e.SetAlerts(ctx, guild, owner, "501", ""); err == nil {
+		t.Error("another server's channel must be refused")
+	}
+	if err := e.SetAlerts(ctx, guild, owner, "500", "201"); err != nil {
+		t.Error(err)
+	}
+
+	// Quarantine role: safe roles below Velox only.
+	for role, ok := range map[string]bool{"200": false, guild: false, "204": false, "299": false, "203": true} {
+		err := e.SetQuarantineRole(ctx, guild, owner, role)
+		if (err == nil) != ok {
+			t.Errorf("quarantine role %s: err=%v", role, err)
+		}
+	}
+
+	// Trust: owner only, never @everyone, bounded.
+	if err := e.Trust(ctx, guild, trustedUser, "user", "50"); !errors.Is(err, ErrNotOwner) {
+		t.Errorf("trusted users must not spread trust: %v", err)
+	}
+	if err := e.Trust(ctx, guild, owner, "role", guild); err == nil {
+		t.Error("trusting @everyone must be refused")
+	}
+	if err := e.Trust(ctx, guild, owner, "user", "404"); err == nil {
+		t.Error("trusting someone not in the server must be refused")
+	}
+	if err := e.Trust(ctx, guild, owner, "role", "201"); err != nil {
+		t.Error(err)
+	}
+	if err := e.Untrust(ctx, guild, admin, "201"); !errors.Is(err, ErrNotOwner) {
+		t.Errorf("only the owner untrusts: %v", err)
+	}
+}
+
+func TestDashboardCommands(t *testing.T) {
+	e, d, st := nukeEngine(t)
+	e.OnAuditLogEntry(ctx, guild, entry(discordgo.AuditLogActionMemberPrune, "50", ""))
+	st.cmds = []securityrepo.Command{
+		{ID: 1, GuildID: 100, CommandType: "release_quarantine", Payload: []byte(`{"user_id":"50; DROP"}`), RequestedBy: 1},
+		{ID: 2, GuildID: 100, CommandType: "release_quarantine", Payload: []byte(`{"user_id":"50"}`), RequestedBy: 1},
+		{ID: 3, GuildID: 100, CommandType: "nope", RequestedBy: 1},
+	}
+	e.ProcessCommands(ctx)
+	if _, ok := st.quarantines[key(100, 50)]; ok {
+		t.Error("the valid release should have run")
+	}
+	if len(st.done) != 3 {
+		t.Errorf("every command must be marked done: %v", st.done)
+	}
+	_ = d
+}
+
+func TestSafeNameDefusesMentionsAndMarkdown(t *testing.T) {
+	got := safeName(&discordgo.User{Username: "x", GlobalName: "@everyone **hi** <@&1> [link](http://a)"})
+	if strings.Contains(got, "@everyone") || strings.Contains(got, "<@&") || strings.Contains(got, "**") || strings.Contains(got, "](") {
+		t.Errorf("unsafe name rendering: %q", got)
+	}
+}

internal/security/session_check.go

@@ -0,0 +1,6 @@
+package security
+
+import "github.com/bwmarrin/discordgo"
+
+// The real session must provide everything the system calls.
+var _ Discord = (*discordgo.Session)(nil)

internal/tickets/manage.go

@@ -182,7 +182,7 @@ func postLog(ctx context.Context, d Discord, st Store, t *ticketrepo.Ticket, tra
 	embed := &discordgo.MessageEmbed{
 		Title:       fmt.Sprintf("Ticket #%04d closed · %s", t.Number, clip(t.CategoryName, 60)),
 		Description: "**" + clip(t.Subject, maxSubject) + "**",
-		Color:       0x6b7280,
+		Color:       accent,
 		Fields: []*discordgo.MessageEmbedField{
 			{Name: "Opened by", Value: "<@" + id(t.OpenerID) + ">", Inline: true},
 			{Name: "Claimed by", Value: claimed, Inline: true},

internal/tickets/open.go

@@ -86,7 +86,6 @@ func IntroEmbed(t *ticketrepo.Ticket, details string) *discordgo.MessageEmbed {
 		Footer: &discordgo.MessageEmbedFooter{Text: "Staff can claim this ticket. Anyone here can close it once it's sorted."},
 	}
 	if t.Status == ticketrepo.StatusClosed {
-		e.Color = 0x6b7280
 		e.Footer.Text = "This ticket is closed."
 	}
 	return e

internal/tickets/panel.go

@@ -15,8 +15,9 @@ import (
 // Custom IDs. Everything starts with "tickets:" so the interaction router can
 // hand it to this package.
 const (
-	idOpenPrefix     = "tickets:open:"     // panel button, + category ID
-	idSelect         = "tickets:select"    // panel dropdown (many categories)
+	idOpenPrefix     = "tickets:open:"     // older panels: one button per category, + category ID
+	idSelect         = "tickets:select"    // panel dropdown
+	idCreate         = "tickets:create"    // panel "Create ticket" button
 	idOpenFormPrefix = "tickets:openform:" // opening form, + category ID
 	idClaim          = "tickets:claim"
 	idClose          = "tickets:close"
@@ -42,8 +43,8 @@ func parseEmoji(s string) *discordgo.ComponentEmoji {
 }
 
 // BuildPanel is the message members open tickets from: an embed with the
-// guild's text and one button per category, or a dropdown once there are
-// more categories than fit comfortably in a row.
+// guild's text and each category's description, a dropdown to pick the
+// category, and a Create ticket button that opens the form for that pick.
 func BuildPanel(s *ticketrepo.Settings, cats []ticketrepo.Category) (*discordgo.MessageEmbed, []discordgo.MessageComponent) {
 	embed := &discordgo.MessageEmbed{
 		Title:       clip(s.PanelTitle, 256),
@@ -54,27 +55,7 @@ func BuildPanel(s *ticketrepo.Settings, cats []ticketrepo.Category) (*discordgo.
 		cats = cats[:maxCategories]
 	}
 
-	if len(cats) <= maxPanelButtons {
-		var buttons []discordgo.MessageComponent
-		for _, c := range cats {
-			buttons = append(buttons, discordgo.Button{
-				Label:    clip(c.Name, 80),
-				Style:    discordgo.PrimaryButton,
-				CustomID: idOpenPrefix + id(c.ID),
-				Emoji:    parseEmoji(c.Emoji),
-			})
-		}
-		// With few categories their descriptions go in the embed, since a
-		// button has no room for one.
-		for _, c := range cats {
-			if c.Description != "" {
-				embed.Fields = append(embed.Fields, &discordgo.MessageEmbedField{Name: clip(c.Name, 256), Value: clip(c.Description, 1024)})
-			}
-		}
-		return embed, []discordgo.MessageComponent{discordgo.ActionsRow{Components: buttons}}
-	}
-
-	var opts []discordgo.SelectMenuOption
+	opts := make([]discordgo.SelectMenuOption, 0, len(cats))
 	for _, c := range cats {
 		opts = append(opts, discordgo.SelectMenuOption{
 			Label:       clip(c.Name, 100),
@@ -82,10 +63,18 @@ func BuildPanel(s *ticketrepo.Settings, cats []ticketrepo.Category) (*discordgo.
 			Description: clip(c.Description, 100),
 			Emoji:       parseEmoji(c.Emoji),
 		})
+		if c.Description != "" {
+			embed.Fields = append(embed.Fields, &discordgo.MessageEmbedField{Name: clip(c.Name, 256), Value: clip(c.Description, 1024)})
 		}
-	return embed, []discordgo.MessageComponent{discordgo.ActionsRow{Components: []discordgo.MessageComponent{
+	}
+	return embed, []discordgo.MessageComponent{
+		discordgo.ActionsRow{Components: []discordgo.MessageComponent{
 			discordgo.SelectMenu{CustomID: idSelect, Placeholder: "Choose what you need help with", Options: opts},
-	}}}
+		}},
+		discordgo.ActionsRow{Components: []discordgo.MessageComponent{
+			discordgo.Button{Label: "Create ticket", Style: discordgo.PrimaryButton, CustomID: idCreate, Emoji: &discordgo.ComponentEmoji{Name: "🎫"}},
+		}},
+	}
 }
 
 // PostPanel posts the panel in the ticket channel, or updates the one it

internal/tickets/pick.go

@@ -0,0 +1,59 @@
+package tickets
+
+import (
+	"sync"
+	"time"
+)
+
+// Discord doesn't send a dropdown's value along with a button click, so the
+// panel's category pick is remembered here between the two interactions:
+// per guild and member, for a short while, in memory. A bot restart forgets
+// it, which only means picking the category again.
+const (
+	pickTTL  = 15 * time.Minute
+	maxPicks = 10000 // a ceiling, so a flood of picks can't grow this forever
+)
+
+type pickKey struct{ guild, user int64 }
+
+type pick struct {
+	category int64
+	at       time.Time
+}
+
+var (
+	picksMu sync.Mutex
+	picks   = map[pickKey]pick{}
+	now     = time.Now
+)
+
+// RememberPick records the category a member chose in the panel dropdown.
+func RememberPick(guildID, userID, categoryID int64) {
+	picksMu.Lock()
+	defer picksMu.Unlock()
+	t := now()
+	k := pickKey{guildID, userID}
+	if _, ok := picks[k]; !ok && len(picks) >= maxPicks {
+		for k, p := range picks {
+			if t.Sub(p.at) > pickTTL {
+				delete(picks, k)
+			}
+		}
+		if len(picks) >= maxPicks {
+			return
+		}
+	}
+	picks[k] = pick{categoryID, t}
+}
+
+// PickedCategory returns the category a member chose, if they did recently.
+func PickedCategory(guildID, userID int64) (int64, bool) {
+	picksMu.Lock()
+	defer picksMu.Unlock()
+	p, ok := picks[pickKey{guildID, userID}]
+	if !ok || now().Sub(p.at) > pickTTL {
+		delete(picks, pickKey{guildID, userID})
+		return 0, false
+	}
+	return p.category, true
+}

internal/tickets/tickets.go

@@ -1,7 +1,8 @@
-// Package tickets is the support ticket system: a panel message with one
-// button per category, a short form, and a private thread per ticket that
-// staff can claim and anyone involved can close. Closing locks and archives
-// the thread and posts a transcript to the log channel.
+// Package tickets is the support ticket system: a panel message with a
+// category dropdown and a Create ticket button, a short form, and a private
+// thread per ticket that staff can claim and anyone involved can close.
+// Closing locks and archives the thread and posts a transcript to the log
+// channel.
 //
 // The Discord and database calls go through small interfaces so the flows
 // can be tested without either; the slash command and button handlers in
@@ -67,7 +68,9 @@ const (
 
 var (
 	defaultStore Store
-	accent       = 0x2b7bfa
+	// Every ticket embed (panel, ticket, log) is orange, so support stands
+	// apart from the bot's other messages.
+	accent = 0xf97316
 )
 
 func Init(s Store) { defaultStore = s }
@@ -80,7 +83,6 @@ const (
 	maxSubject      = 100
 	maxDetails      = 1000
 	maxReason       = 300
-	maxPanelButtons = 5 // more categories than this switch the panel to a dropdown
 	maxCategories   = 25
 	autoArchiveWeek = 10080
 )

internal/tickets/tickets_test.go

@@ -74,26 +74,77 @@ func TestBuildPanel(t *testing.T) {
 		{ID: 2, Name: "Appeal", Emoji: "<a:party:123>"},
 	}
 	embed, comps := BuildPanel(s, cats)
-	row := comps[0].(discordgo.ActionsRow)
-	b1, b2 := row.Components[0].(discordgo.Button), row.Components[1].(discordgo.Button)
-	if embed.Title != "Help" || b1.CustomID != "tickets:open:1" || b1.Emoji.Name != "🛟" {
-		t.Errorf("first button wrong: %+v", b1)
+	if embed.Title != "Help" || embed.Color != 0xf97316 {
+		t.Errorf("panel embed wrong: %+v", embed)
 	}
-	if b2.Emoji.ID != "123" || b2.Emoji.Name != "party" || !b2.Emoji.Animated {
-		t.Errorf("custom emoji not parsed: %+v", b2.Emoji)
+	if len(comps) != 2 {
+		t.Fatalf("want a dropdown row and a button row, got %d rows", len(comps))
+	}
+	menu := comps[0].(discordgo.ActionsRow).Components[0].(discordgo.SelectMenu)
+	if menu.CustomID != "tickets:select" || len(menu.Options) != 2 || menu.Options[0].Value != "1" || menu.Options[0].Emoji.Name != "🛟" {
+		t.Errorf("dropdown wrong: %+v", menu)
+	}
+	if e := menu.Options[1].Emoji; e.ID != "123" || e.Name != "party" || !e.Animated {
+		t.Errorf("custom emoji not parsed: %+v", e)
+	}
+	button := comps[1].(discordgo.ActionsRow).Components[0].(discordgo.Button)
+	if button.CustomID != "tickets:create" || button.Label != "Create ticket" {
+		t.Errorf("create button wrong: %+v", button)
 	}
 	if len(embed.Fields) != 1 || embed.Fields[0].Value != "General help" {
 		t.Errorf("descriptions belong in the embed: %+v", embed.Fields)
 	}
 
 	var many []ticketrepo.Category
-	for i := 1; i <= 7; i++ {
+	for i := 1; i <= 30; i++ {
 		many = append(many, ticketrepo.Category{ID: int64(i), Name: fmt.Sprint("Cat ", i)})
 	}
 	_, comps = BuildPanel(s, many)
-	menu := comps[0].(discordgo.ActionsRow).Components[0].(discordgo.SelectMenu)
-	if menu.CustomID != "tickets:select" || len(menu.Options) != 7 || menu.Options[6].Value != "7" {
-		t.Errorf("more than 5 categories should use a dropdown: %+v", menu)
+	if n := len(comps[0].(discordgo.ActionsRow).Components[0].(discordgo.SelectMenu).Options); n != 25 {
+		t.Errorf("a dropdown holds at most 25 options, got %d", n)
+	}
+}
+
+func TestPicks(t *testing.T) {
+	clock := time.Date(2026, 10, 21, 12, 0, 0, 0, time.UTC)
+	now = func() time.Time { return clock }
+	t.Cleanup(func() { now = time.Now; picks = map[pickKey]pick{} })
+
+	if _, ok := PickedCategory(guild, 5); ok {
+		t.Error("nothing picked yet")
+	}
+	RememberPick(guild, 5, 3)
+	RememberPick(guild, 5, 4)
+	RememberPick(guild, 6, 9)
+	if c, ok := PickedCategory(guild, 5); !ok || c != 4 {
+		t.Errorf("the latest pick wins: %d %v", c, ok)
+	}
+	if _, ok := PickedCategory(guild+1, 5); ok {
+		t.Error("picks are per guild")
+	}
+
+	clock = clock.Add(pickTTL + time.Second)
+	if _, ok := PickedCategory(guild, 5); ok {
+		t.Error("a pick expires")
+	}
+
+	// Full: new members can't add more, but expired ones make room.
+	picks = map[pickKey]pick{}
+	for i := 0; i < maxPicks; i++ {
+		picks[pickKey{guild + 100, int64(i)}] = pick{1, clock}
+	}
+	RememberPick(guild, 7, 1)
+	if _, ok := PickedCategory(guild, 7); ok {
+		t.Error("a full map takes no new members")
+	}
+	RememberPick(guild+100, 0, 2)
+	if c, _ := PickedCategory(guild+100, 0); c != 2 {
+		t.Error("someone already in the map can still change their pick")
+	}
+	clock = clock.Add(pickTTL + time.Second)
+	RememberPick(guild, 7, 1)
+	if _, ok := PickedCategory(guild, 7); !ok {
+		t.Error("expired picks should be cleared to make room")
 	}
 }
 

main.go

@@ -17,6 +17,7 @@ import (
 	"velox-bot/internal/db/repos/projectsrepo"
 	"velox-bot/internal/db/repos/rpsrepo"
 	"velox-bot/internal/db/repos/schedulerepo"
+	"velox-bot/internal/db/repos/securityrepo"
 	"velox-bot/internal/db/repos/settingsrepo"
 	"velox-bot/internal/db/repos/ticketrepo"
 	"velox-bot/internal/db/repos/twitchrepo"
@@ -35,6 +36,7 @@ import (
 	"velox-bot/internal/db/services/twitch"
 	"velox-bot/internal/db/services/usersettings"
 	"velox-bot/internal/db/services/welcome"
+	"velox-bot/internal/security"
 )
 
 func main() {
@@ -62,6 +64,7 @@ func main() {
 	twitchRepo := twitchrepo.NewRepo(db)
 	defaultRoleRepo := defaultrolerepo.NewRepo(db)
 	cmdtickets.Init(ticketrepo.NewRepo(db))
+	security.Configure(securityrepo.NewRepo(db))
 	levelService := level.New(levelRepo, settingsRepo)
 	levelSettingsService := levelsettings.New(settingsRepo)
 	logSettingsService := logsettings.New(settingsRepo)

schema.sql

@@ -228,3 +228,162 @@ CREATE TABLE IF NOT EXISTS ticket_commands (
     created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
     processed_at TIMESTAMPTZ
 );
+
+-- Security: anti-raid and anti-nuke (mirror of velox-dashboard-api migration 000017_security)
+CREATE TABLE IF NOT EXISTS security_settings (
+    guild_id BIGINT PRIMARY KEY,
+    -- Where alerts go, and who gets pinged for raids and nukes.
+    alert_channel_id BIGINT,
+    alert_role_id BIGINT,
+
+    -- Join Gate: checks run on every join, each with its own action.
+    joingate_enabled BOOLEAN NOT NULL DEFAULT FALSE,
+    joingate_no_avatar TEXT NOT NULL DEFAULT 'off' CHECK (joingate_no_avatar IN ('off', 'timeout', 'kick', 'ban')),
+    joingate_new_account TEXT NOT NULL DEFAULT 'off' CHECK (joingate_new_account IN ('off', 'timeout', 'kick', 'ban')),
+    joingate_min_account_age_days INT NOT NULL DEFAULT 7 CHECK (joingate_min_account_age_days BETWEEN 1 AND 365),
+    joingate_advertising_name TEXT NOT NULL DEFAULT 'off' CHECK (joingate_advertising_name IN ('off', 'timeout', 'kick', 'ban')),
+    joingate_username_filter TEXT NOT NULL DEFAULT 'off' CHECK (joingate_username_filter IN ('off', 'timeout', 'kick', 'ban')),
+    joingate_username_patterns TEXT[] NOT NULL DEFAULT '{}',
+    joingate_unverified_bot TEXT NOT NULL DEFAULT 'off' CHECK (joingate_unverified_bot IN ('off', 'kick', 'ban')),
+    -- A bot added by someone who isn't the owner or trusted.
+    joingate_unauthorized_bot TEXT NOT NULL DEFAULT 'kick' CHECK (joingate_unauthorized_bot IN ('off', 'kick', 'ban')),
+
+    -- Raid mode: raid_join_count joins within raid_join_seconds starts it; it
+    -- ends after raid_quiet_minutes without a join, or when staff end it.
+    antiraid_enabled BOOLEAN NOT NULL DEFAULT FALSE,
+    raid_join_count INT NOT NULL DEFAULT 10 CHECK (raid_join_count BETWEEN 3 AND 100),
+    raid_join_seconds INT NOT NULL DEFAULT 10 CHECK (raid_join_seconds BETWEEN 5 AND 300),
+    raid_action TEXT NOT NULL DEFAULT 'kick' CHECK (raid_action IN ('alert', 'timeout', 'kick', 'ban')),
+    raid_pause_invites BOOLEAN NOT NULL DEFAULT TRUE,
+    raid_quiet_minutes INT NOT NULL DEFAULT 10 CHECK (raid_quiet_minutes BETWEEN 1 AND 120),
+
+    -- Anti-nuke: anyone who isn't the owner or trusted and goes over a limit
+    -- within antinuke_window_seconds is quarantined. Limits are per action
+    -- (channel_delete, channel_create, role_delete, role_create, ban, kick,
+    -- webhook_create); a limit of 0 means the action is never allowed.
+    antinuke_enabled BOOLEAN NOT NULL DEFAULT FALSE,
+    antinuke_window_seconds INT NOT NULL DEFAULT 10 CHECK (antinuke_window_seconds BETWEEN 5 AND 300),
+    antinuke_limits JSONB NOT NULL DEFAULT '{"channel_delete": 2, "channel_create": 5, "role_delete": 2, "role_create": 5, "ban": 3, "kick": 5, "webhook_create": 3}',
+    -- Also lock every channel when a nuke is stopped.
+    antinuke_lock_server BOOLEAN NOT NULL DEFAULT FALSE,
+    quarantine_role_id BIGINT,
+
+    -- Restore: snapshots of roles and channels are taken every few hours; a
+    -- restore recreates what's missing. Automatic after a stopped nuke when
+    -- antinuke_auto_restore is on, otherwise by the owner or trusted.
+    antinuke_auto_restore BOOLEAN NOT NULL DEFAULT FALSE,
+
+    -- Heat: every message adds heat to its author (more for repeats,
+    -- mentions, emoji walls, links, blocked words; an invite link maxes it),
+    -- and heat cools down over time. Reaching the maximum deletes the message
+    -- and applies heat_action. heat_strictness scales how fast heat builds.
+    heat_enabled BOOLEAN NOT NULL DEFAULT FALSE,
+    heat_strictness TEXT NOT NULL DEFAULT 'medium' CHECK (heat_strictness IN ('low', 'medium', 'high')),
+    heat_action TEXT NOT NULL DEFAULT 'timeout' CHECK (heat_action IN ('timeout', 'kick', 'ban')),
+    heat_timeout_minutes INT NOT NULL DEFAULT 10 CHECK (heat_timeout_minutes BETWEEN 1 AND 10080),
+    -- Each new offence within a day doubles the timeout (capped at 28 days).
+    heat_escalate BOOLEAN NOT NULL DEFAULT TRUE,
+    heat_blocked_words TEXT[] NOT NULL DEFAULT '{}',
+    -- Heat panic: this many members maxing out within a minute times out
+    -- anyone who joined in the last day as soon as they speak, for 10
+    -- minutes. 0 turns it off.
+    heat_panic_members INT NOT NULL DEFAULT 3 CHECK (heat_panic_members BETWEEN 0 AND 50),
+    -- Mention flood: this many mentions by non-exempt members within 30
+    -- seconds locks every channel. 0 turns it off.
+    heat_lockdown_mentions INT NOT NULL DEFAULT 0 CHECK (heat_lockdown_mentions BETWEEN 0 AND 1000),
+
+    -- Join lockdown (/lockdown joins): every new member is kicked or banned.
+    join_lock TEXT NOT NULL DEFAULT 'off' CHECK (join_lock IN ('off', 'kick', 'ban'))
+);
+
+-- Users and roles exempt from anti-nuke, who may also manage its settings.
+-- The server owner is always trusted and never listed here.
+CREATE TABLE IF NOT EXISTS security_trusted (
+    guild_id BIGINT NOT NULL,
+    target_id BIGINT NOT NULL,
+    kind TEXT NOT NULL CHECK (kind IN ('user', 'role')),
+    added_by BIGINT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    PRIMARY KEY (guild_id, target_id)
+);
+
+-- Members currently quarantined, with the roles they had, so releasing them
+-- gives every role back.
+CREATE TABLE IF NOT EXISTS security_quarantines (
+    guild_id BIGINT NOT NULL,
+    user_id BIGINT NOT NULL,
+    previous_role_ids BIGINT[] NOT NULL DEFAULT '{}',
+    reason TEXT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    PRIMARY KEY (guild_id, user_id)
+);
+
+-- Channels the bot locked, with @everyone's permission overwrite from before,
+-- so unlocking puts back exactly what was there.
+CREATE TABLE IF NOT EXISTS security_lockdowns (
+    guild_id BIGINT NOT NULL,
+    channel_id BIGINT NOT NULL,
+    had_overwrite BOOLEAN NOT NULL,
+    previous_allow BIGINT NOT NULL DEFAULT 0,
+    previous_deny BIGINT NOT NULL DEFAULT 0,
+    server_wide BOOLEAN NOT NULL DEFAULT FALSE,
+    locked_by BIGINT NOT NULL,
+    locked_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    PRIMARY KEY (guild_id, channel_id)
+);
+
+-- A raid in progress, so raid mode survives a bot restart: the quiet timer
+-- carries on and the summary still lists everyone caught.
+CREATE TABLE IF NOT EXISTS security_raids (
+    guild_id BIGINT PRIMARY KEY,
+    started_at TIMESTAMPTZ NOT NULL,
+    last_join_at TIMESTAMPTZ NOT NULL,
+    invites_paused BOOLEAN NOT NULL DEFAULT FALSE,
+    caught_total INT NOT NULL DEFAULT 0
+);
+
+CREATE TABLE IF NOT EXISTS security_raid_caught (
+    guild_id BIGINT NOT NULL,
+    user_id BIGINT NOT NULL,
+    action TEXT NOT NULL,
+    name TEXT NOT NULL,
+    caught_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    PRIMARY KEY (guild_id, user_id)
+);
+
+-- Snapshots of a guild's roles and channels for restoring after a nuke. The
+-- bot keeps the last three per guild.
+CREATE TABLE IF NOT EXISTS security_snapshots (
+    id BIGSERIAL PRIMARY KEY,
+    guild_id BIGINT NOT NULL,
+    data JSONB NOT NULL,
+    roles INT NOT NULL,
+    channels INT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS security_snapshots_guild_idx ON security_snapshots (guild_id, created_at DESC);
+
+-- What the system did, for the dashboard's history.
+CREATE TABLE IF NOT EXISTS security_events (
+    id BIGSERIAL PRIMARY KEY,
+    guild_id BIGINT NOT NULL,
+    kind TEXT NOT NULL,
+    actor_id BIGINT,
+    target_id BIGINT,
+    detail TEXT NOT NULL DEFAULT '',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS security_events_guild_idx ON security_events (guild_id, created_at DESC);
+
+-- Dashboard -> bot requests, same pattern as music_commands.
+CREATE TABLE IF NOT EXISTS security_commands (
+    id BIGSERIAL PRIMARY KEY,
+    guild_id BIGINT NOT NULL,
+    command_type TEXT NOT NULL CHECK (command_type IN ('end_raid', 'release_quarantine', 'unlock_server', 'unlock_joins', 'snapshot', 'restore')),
+    payload JSONB,
+    requested_by BIGINT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    processed_at TIMESTAMPTZ
+);