package music

import (
	"testing"

	"github.com/disgoorg/disgolink/v4/lavalink"
)

func TestQueuePushPop(t *testing.T) {
	q := NewQueue()

	if _, ok := q.Pop(); ok {
		t.Fatal("expected empty queue to return ok=false")
	}

	first := lavalink.Track{Info: lavalink.TrackInfo{Title: "first"}}
	second := lavalink.Track{Info: lavalink.TrackInfo{Title: "second"}}

	q.Push(first)
	q.Push(second)

	if got := q.Len(); got != 2 {
		t.Fatalf("expected length 2, got %d", got)
	}

	track, ok := q.Pop()
	if !ok || track.Info.Title != "first" {
		t.Fatalf("expected first track, got %+v ok=%v", track, ok)
	}

	track, ok = q.Pop()
	if !ok || track.Info.Title != "second" {
		t.Fatalf("expected second track, got %+v ok=%v", track, ok)
	}

	if _, ok := q.Pop(); ok {
		t.Fatal("expected queue to be empty after popping all tracks")
	}
}

func TestQueueClear(t *testing.T) {
	q := NewQueue()
	q.Push(lavalink.Track{})
	q.Push(lavalink.Track{})

	q.Clear()

	if got := q.Len(); got != 0 {
		t.Fatalf("expected length 0 after clear, got %d", got)
	}
}

func TestQueueRemoveAt(t *testing.T) {
	q := NewQueue()
	q.Push(lavalink.Track{Info: lavalink.TrackInfo{Title: "first"}})
	q.Push(lavalink.Track{Info: lavalink.TrackInfo{Title: "second"}})
	q.Push(lavalink.Track{Info: lavalink.TrackInfo{Title: "third"}})

	track, ok := q.RemoveAt(1)
	if !ok || track.Info.Title != "second" {
		t.Fatalf("expected to remove second track, got %+v ok=%v", track, ok)
	}

	if got := q.Len(); got != 2 {
		t.Fatalf("expected length 2 after removal, got %d", got)
	}

	list := q.List()
	if list[0].Info.Title != "first" || list[1].Info.Title != "third" {
		t.Fatalf("unexpected queue order after removal: %+v", list)
	}

	if _, ok := q.RemoveAt(5); ok {
		t.Fatal("expected out-of-range removal to return ok=false")
	}
	if _, ok := q.RemoveAt(-1); ok {
		t.Fatal("expected negative index removal to return ok=false")
	}
}

func TestQueueShuffle(t *testing.T) {
	q := NewQueue()
	for i := 0; i < 5; i++ {
		q.Push(lavalink.Track{Info: lavalink.TrackInfo{Title: string(rune('a' + i))}})
	}

	if count := q.Shuffle(); count != 5 {
		t.Fatalf("expected shuffle to report 5 tracks, got %d", count)
	}

	if got := q.Len(); got != 5 {
		t.Fatalf("expected length to stay 5 after shuffle, got %d", got)
	}

	seen := make(map[string]bool)
	for _, track := range q.List() {
		seen[track.Info.Title] = true
	}
	for i := 0; i < 5; i++ {
		title := string(rune('a' + i))
		if !seen[title] {
			t.Fatalf("expected shuffled queue to still contain %q", title)
		}
	}
}

func TestQueueListReturnsCopy(t *testing.T) {
	q := NewQueue()
	q.Push(lavalink.Track{Info: lavalink.TrackInfo{Title: "only"}})

	list := q.List()
	list[0].Info.Title = "mutated"

	track, _ := q.Pop()
	if track.Info.Title != "only" {
		t.Fatalf("expected internal queue to be unaffected by mutation of returned list, got %q", track.Info.Title)
	}
}