package public

import (
	"fmt"
	"strings"

	"velox-bot/internal/commands/music/shared"
	"velox-bot/internal/music"

	"github.com/bwmarrin/discordgo"
)

// Queue editing. Pausing, skipping, repeating and stopping are buttons on the
// now-playing message, so the only queue controls that need commands are
// removing a song and moving one. They need the DJ role, like /play, /queue
// and /volume. Turning music on or off needs Manage Server.

func positionOption(name, desc string) *discordgo.ApplicationCommandOption {
	return &discordgo.ApplicationCommandOption{
		Type: discordgo.ApplicationCommandOptionInteger, Name: name, Description: desc,
		Required: true, MinValue: ptrFloat(1), MaxValue: 1000,
	}
}

func playerOptions() []*discordgo.ApplicationCommandOption {
	sub := func(name, desc string, o ...*discordgo.ApplicationCommandOption) *discordgo.ApplicationCommandOption {
		return &discordgo.ApplicationCommandOption{Type: discordgo.ApplicationCommandOptionSubCommand, Name: name, Description: desc, Options: o}
	}
	return []*discordgo.ApplicationCommandOption{
		sub("remove", "Remove a song from the queue (DJ)", positionOption("position", "Its number in /queue")),
		sub("move", "Move a song to another place in the queue (DJ)",
			positionOption("from", "Its number in /queue"), positionOption("to", "The number it should have")),
	}
}

// queueEntry returns the queued song at position n (1 is the first one after
// the song that is playing), as /queue numbers them.
func queueEntry(guildID string, n int) (*music.TrackEntry, int) {
	_, rest := music.GetQueue(guildID)
	if n < 1 || n > len(rest) {
		return nil, len(rest)
	}
	e := rest[n-1]
	return &e, len(rest)
}

func title(e *music.TrackEntry) string {
	return strings.TrimSpace(e.Track.Info.Title)
}

// handlePlayer runs a queue subcommand. The caller has checked that music is
// on and that the member has the DJ role. Pause, skip, repeat and stop are
// buttons on the now-playing message, so only what has no button is a command.
func handlePlayer(s *discordgo.Session, i *discordgo.InteractionCreate, sub *discordgo.ApplicationCommandInteractionDataOption) {
	g := i.GuildID
	args := map[string]*discordgo.ApplicationCommandInteractionDataOption{}
	for _, o := range sub.Options {
		args[o.Name] = o
	}

	var err error
	var msg string
	switch sub.Name {
	case "remove":
		n := int(args["position"].IntValue())
		e, size := queueEntry(g, n)
		if e == nil {
			shared.RespondEphemeral(s, i, fmt.Sprintf("There is no song number %d in the queue (it has %d).", n, size))
			return
		}
		err, msg = music.RemoveFromQueue(g, e.QueueID), fmt.Sprintf("Removed **%s**.", title(e))
	case "move":
		from, to := int(args["from"].IntValue()), int(args["to"].IntValue())
		e, size := queueEntry(g, from)
		if e == nil {
			shared.RespondEphemeral(s, i, fmt.Sprintf("There is no song number %d in the queue (it has %d).", from, size))
			return
		}
		if to > size {
			to = size
		}
		err, msg = music.Reorder(g, e.QueueID, to), fmt.Sprintf("Moved **%s** to number %d.", title(e), to)
	default:
		shared.RespondEphemeral(s, i, "Unknown subcommand.")
		return
	}
	if err != nil {
		shared.RespondEphemeral(s, i, "That didn't work: "+err.Error())
		return
	}
	shared.RespondEphemeral(s, i, msg)
}