Implement slash commands for playback control

internal/commands/shuffle.go

@@ -0,0 +1,37 @@
+package commands
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/disgoorg/disgo/discord"
+	"github.com/disgoorg/disgo/events"
+)
+
+type ShuffleCommand struct {
+	deps *Dependencies
+}
+
+func NewShuffleCommand(deps *Dependencies) *ShuffleCommand {
+	return &ShuffleCommand{deps: deps}
+}
+
+func (c *ShuffleCommand) Definition() discord.ApplicationCommandCreate {
+	return discord.SlashCommandCreate{
+		Name:        "shuffle",
+		Description: "Shuffles the upcoming tracks in the queue",
+	}
+}
+
+func (c *ShuffleCommand) Execute(ctx context.Context, event *events.ApplicationCommandInteractionCreate) error {
+	gid, err := requirePlaybackAccess(c.deps.Discord, event)
+	if err != nil {
+		return err
+	}
+
+	count := c.deps.Music.Guild(gid).Shuffle()
+	if count == 0 {
+		return reply(event, "The queue is empty, nothing to shuffle.")
+	}
+	return reply(event, fmt.Sprintf("Shuffled **%d** queued track(s).", count))
+}