Implement slash commands for playback control

internal/commands/seek.go

@@ -0,0 +1,63 @@
+package commands
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"github.com/disgoorg/disgo/discord"
+	"github.com/disgoorg/disgo/events"
+
+	"discord-music-bot/internal/music"
+)
+
+type SeekCommand struct {
+	deps *Dependencies
+}
+
+func NewSeekCommand(deps *Dependencies) *SeekCommand {
+	return &SeekCommand{deps: deps}
+}
+
+func (c *SeekCommand) Definition() discord.ApplicationCommandCreate {
+	return discord.SlashCommandCreate{
+		Name:        "seek",
+		Description: "Jumps to a position in the current track",
+		Options: []discord.ApplicationCommandOption{
+			discord.ApplicationCommandOptionString{
+				Name:        "position",
+				Description: "Position to seek to: seconds, mm:ss or hh:mm:ss (e.g. 90 or 1:30)",
+				Required:    true,
+			},
+		},
+	}
+}
+
+func (c *SeekCommand) Execute(ctx context.Context, event *events.ApplicationCommandInteractionCreate) error {
+	gid, err := requirePlaybackAccess(c.deps.Discord, event)
+	if err != nil {
+		return err
+	}
+
+	raw := event.SlashCommandInteractionData().String("position")
+	position, err := parsePosition(raw)
+	if err != nil {
+		return rejectEphemeral(event, fmt.Sprintf("Invalid position %q: %s", raw, err))
+	}
+
+	if err := c.deps.Music.Guild(gid).Seek(ctx, position); err != nil {
+		return replyWithError(event, seekErrorMessage(err), err)
+	}
+	return reply(event, fmt.Sprintf("Seeked to **%s**.", position))
+}
+
+func seekErrorMessage(err error) string {
+	switch {
+	case errors.Is(err, music.ErrNoTrackPlaying):
+		return "Nothing is playing right now."
+	case errors.Is(err, music.ErrStreamNotSeekable):
+		return "Can't seek within a live stream."
+	default:
+		return "Could not seek."
+	}
+}