feat: add welcome message functionality

- Introduced a new welcome service and repository for managing welcome messages, channels, and GIFs.
- Added commands to set welcome channel, message, DM, and GIF through the bot's configuration.
- Implemented event handling for new guild members to send welcome messages and DMs based on configuration.
- Updated main application to include the new welcome service in the bot's services.

internal/db/repos/welcomerepo/repo.go

@@ -0,0 +1,111 @@
+package welcomerepo
+
+import (
+	"context"
+	"database/sql"
+)
+
+type Repo struct {
+	db *sql.DB
+}
+
+type Settings struct {
+	GuildID          int64
+	ChannelID        int64
+	WelcomeMessage   string
+	WelcomeDM        string
+	WelcomeGIFURL    string
+	HasConfiguration bool
+}
+
+func NewRepo(db *sql.DB) *Repo {
+	return &Repo{db: db}
+}
+
+func (r *Repo) GetSettings(ctx context.Context, guildID int64) (*Settings, error) {
+	const q = `
+		SELECT welcome_channel_id, welcome_message, welcome_dm, welcome_gif_url
+		FROM welcome
+		WHERE guild_id = $1
+	`
+	row := r.db.QueryRowContext(ctx, q, guildID)
+	var ch sql.NullInt64
+	var msg, dm, gif sql.NullString
+
+	switch err := row.Scan(&ch, &msg, &dm, &gif); err {
+	case nil:
+		s := &Settings{
+			GuildID:          guildID,
+			ChannelID:        0,
+			WelcomeMessage:   "",
+			WelcomeDM:        "",
+			WelcomeGIFURL:    "",
+			HasConfiguration: true,
+		}
+		if ch.Valid {
+			s.ChannelID = ch.Int64
+		}
+		if msg.Valid {
+			s.WelcomeMessage = msg.String
+		}
+		if dm.Valid {
+			s.WelcomeDM = dm.String
+		}
+		if gif.Valid {
+			s.WelcomeGIFURL = gif.String
+		}
+		return s, nil
+	case sql.ErrNoRows:
+		return &Settings{
+			GuildID:          guildID,
+			HasConfiguration: false,
+		}, nil
+	default:
+		return nil, err
+	}
+}
+
+func (r *Repo) UpsertChannel(ctx context.Context, guildID, channelID int64) error {
+	const q = `
+		INSERT INTO welcome (guild_id, welcome_channel_id)
+		VALUES ($1, $2)
+		ON CONFLICT (guild_id)
+		DO UPDATE SET welcome_channel_id = EXCLUDED.welcome_channel_id
+	`
+	_, err := r.db.ExecContext(ctx, q, guildID, channelID)
+	return err
+}
+
+func (r *Repo) UpsertMessage(ctx context.Context, guildID int64, message string) error {
+	const q = `
+		INSERT INTO welcome (guild_id, welcome_message)
+		VALUES ($1, $2)
+		ON CONFLICT (guild_id)
+		DO UPDATE SET welcome_message = EXCLUDED.welcome_message
+	`
+	_, err := r.db.ExecContext(ctx, q, guildID, message)
+	return err
+}
+
+func (r *Repo) UpsertDM(ctx context.Context, guildID int64, dm string) error {
+	const q = `
+		INSERT INTO welcome (guild_id, welcome_dm)
+		VALUES ($1, $2)
+		ON CONFLICT (guild_id)
+		DO UPDATE SET welcome_dm = EXCLUDED.welcome_dm
+	`
+	_, err := r.db.ExecContext(ctx, q, guildID, dm)
+	return err
+}
+
+func (r *Repo) UpsertGIF(ctx context.Context, guildID int64, gifURL string) error {
+	const q = `
+		INSERT INTO welcome (guild_id, welcome_gif_url)
+		VALUES ($1, $2)
+		ON CONFLICT (guild_id)
+		DO UPDATE SET welcome_gif_url = EXCLUDED.welcome_gif_url
+	`
+	_, err := r.db.ExecContext(ctx, q, guildID, gifURL)
+	return err
+}
+

internal/db/services/services.go

@@ -9,6 +9,7 @@ import (
 	"velox-bot/internal/db/services/schedule"
 	"velox-bot/internal/db/services/twitch"
 	"velox-bot/internal/db/services/usersettings"
+	"velox-bot/internal/db/services/welcome"
 )
 
 type Services struct {
@@ -20,11 +21,12 @@ type Services struct {
 	Projects      *projects.Service
 	RPS           *rps.Service
 	Twitch        *twitch.Service
+	Welcome       *welcome.Service
 }
 
 var Global *Services
 
-func NewServices(level *level.Service, levelSettings *levelsettings.Service, meeting *meeting.Service, schedule *schedule.Service, userSettings *usersettings.Service, projects *projects.Service, rps *rps.Service, twitchSvc *twitch.Service) *Services {
+func NewServices(level *level.Service, levelSettings *levelsettings.Service, meeting *meeting.Service, schedule *schedule.Service, userSettings *usersettings.Service, projects *projects.Service, rps *rps.Service, twitchSvc *twitch.Service, welcomeSvc *welcome.Service) *Services {
 	s := &Services{
 		Level:         level,
 		LevelSettings: levelSettings,
@@ -34,6 +36,7 @@ func NewServices(level *level.Service, levelSettings *levelsettings.Service, mee
 		Projects:      projects,
 		RPS:           rps,
 		Twitch:        twitchSvc,
+		Welcome:       welcomeSvc,
 	}
 	Global = s
 	return s

internal/db/services/welcome/service.go

@@ -0,0 +1,36 @@
+package welcome
+
+import (
+	"context"
+
+	"velox-bot/internal/db/repos/welcomerepo"
+)
+
+type Service struct {
+	repo *welcomerepo.Repo
+}
+
+func New(repo *welcomerepo.Repo) *Service {
+	return &Service{repo: repo}
+}
+
+func (s *Service) GetSettings(ctx context.Context, guildID int64) (*welcomerepo.Settings, error) {
+	return s.repo.GetSettings(ctx, guildID)
+}
+
+func (s *Service) SetChannel(ctx context.Context, guildID, channelID int64) error {
+	return s.repo.UpsertChannel(ctx, guildID, channelID)
+}
+
+func (s *Service) SetMessage(ctx context.Context, guildID int64, message string) error {
+	return s.repo.UpsertMessage(ctx, guildID, message)
+}
+
+func (s *Service) SetDM(ctx context.Context, guildID int64, dm string) error {
+	return s.repo.UpsertDM(ctx, guildID, dm)
+}
+
+func (s *Service) SetGIF(ctx context.Context, guildID int64, gifURL string) error {
+	return s.repo.UpsertGIF(ctx, guildID, gifURL)
+}
+