package playlist_test

import (
	"io"
	"segmento/pkg/media"
	"segmento/pkg/playlist"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
)

type FakeReader struct {
}

func (r *FakeReader) Read([]byte) (int, error) {
	return 0, nil
}

type FakeSegmenter struct {
	count int
}

func (s *FakeSegmenter) Segment(r io.Reader) (chan *media.Segment, error) {
	c := make(chan *media.Segment)

	go func() {
		dur := 2500 * time.Millisecond
		for i := 0; i < s.count; i++ {
			segment := media.NewSegment(dur, 0)
			segment.IncrementDuration(dur)
			c <- segment
		}
		close(c)
	}()

	return c, nil
}

type FakeSegmentPublisher struct {
	count int
}

func (p *FakeSegmentPublisher) Publish(s *media.Segment) (string, error) {
	p.count++
	return "", nil
}

type consumer struct {
	pCount, sCount int
}

func (c *consumer) PlaylistUpdated(p playlist.Playlist) {
	c.pCount++
}

func (c *consumer) PlaylistSegmentAdded(p playlist.Playlist, s *playlist.PlaylistSegment) {
	c.sCount++
}

func TestMediaPlaylistImplements(t *testing.T) {
	require.Implements(t, (*playlist.Playlist)(nil), new(playlist.MediaPlaylist))
}

func TestMediaPlaylist(t *testing.T) {
	publisher := &FakeSegmentPublisher{}
	playlist := playlist.NewMediaPlaylist(&FakeReader{}, &FakeSegmenter{3}, publisher)

	err := playlist.Run()
	require.NoError(t, err)
	require.Equal(t, 3, playlist.Len())
	require.Equal(t, 3, publisher.count)
}

func TestMediaPlaylistRender(t *testing.T) {
	playlist := playlist.NewMediaPlaylist(&FakeReader{}, &FakeSegmenter{2}, &FakeSegmentPublisher{})
	err := playlist.Run()
	require.NoError(t, err)

	lines := strings.Split(playlist.Render(), "\n")

	require.Equal(t, "#EXTM3U", lines[0])
	require.Equal(t, "#EXT-X-VERSION:3", lines[1])
	require.Equal(t, "#EXT-X-TARGETDURATION:3", lines[2])
	require.Equal(t, "#EXTINF:2.50000", lines[3])
	require.Equal(t, "http://www.example.com/x.mp3", lines[4])
	require.Equal(t, "#EXTINF:2.50000", lines[5])
	require.Equal(t, "http://www.example.com/x.mp3", lines[6])
}

func TestMediaPlaylistConsumer(t *testing.T) {
	consumer := &consumer{}
	require.Implements(t, (*playlist.Consumer)(nil), consumer)

	playlist := playlist.NewMediaPlaylist(&FakeReader{}, &FakeSegmenter{4}, &FakeSegmentPublisher{})
	playlist.AddConsumer(consumer)
	err := playlist.Run()
	require.NoError(t, err)
	require.Equal(t, 4, consumer.sCount)
	require.Equal(t, 0, consumer.pCount) // TODO
}