Implement slash commands for playback control

internal/commands/queue.go

@@ -0,0 +1,44 @@
+package commands
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/disgoorg/disgo/discord"
+	"github.com/disgoorg/disgo/events"
+)
+
+type QueueCommand struct {
+	deps *Dependencies
+}
+
+func NewQueueCommand(deps *Dependencies) *QueueCommand {
+	return &QueueCommand{deps: deps}
+}
+
+func (c *QueueCommand) Definition() discord.ApplicationCommandCreate {
+	return discord.SlashCommandCreate{
+		Name:        "queue",
+		Description: "Shows the upcoming tracks",
+	}
+}
+
+func (c *QueueCommand) Execute(ctx context.Context, event *events.ApplicationCommandInteractionCreate) error {
+	gid, ok := guildID(event)
+	if !ok {
+		return guildOnlyError(event)
+	}
+
+	tracks := c.deps.Music.Guild(gid).Queued()
+	if len(tracks) == 0 {
+		return reply(event, "The queue is empty.")
+	}
+
+	var builder strings.Builder
+	builder.WriteString("Up next:\n")
+	for i, track := range tracks {
+		fmt.Fprintf(&builder, "%d. **%s** (%s)\n", i+1, track.Info.Title, track.Info.Length)
+	}
+	return reply(event, builder.String())
+}