package media

import (
	"io"
	"io/ioutil"
	"os"
	"sync"
	"testing"

	. "github.com/smartystreets/goconvey/convey"
)

func Test_Demux(t *testing.T) {
	Convey("Demux", t, func() {
		Convey("audio-only", func() {
			reader, _ := os.Open("mpthreetest.mp3")
			defer reader.Close()

			demuxer := Demux(reader)
			var audioStream *DemuxedStream
			var err error
		forloop:
			for {
				select {
				case err = <-demuxer.Error():
					break forloop
				case stream := <-demuxer.Streams():
					So(audioStream, ShouldBeNil)
					So(stream.StreamId, ShouldEqual, 0)
					So(stream.Pts, ShouldEqual, 0)
					So(stream.CodecInfo.CodecName, ShouldEqual, "mp3")
					So(stream.CodecInfo.Type, ShouldEqual, Audio)
					audioStream = stream
				}
			}
			So(err, ShouldBeNil)

			audioReader := audioStream.Sub()

			n, err := io.Copy(ioutil.Discard, audioReader)
			So(err, ShouldBeNil)
			So(n, ShouldBeGreaterThan, 0)
		})

		Convey("video and audio", func() {
			reader, _ := os.Open("small.ogv")
			defer reader.Close()

			demuxer := Demux(reader)
			var audioStream, videoStream *DemuxedStream
			var err error
		forloop:
			for {
				select {
				case err = <-demuxer.Error():
					break forloop
				case stream := <-demuxer.Streams():
					So(stream.Pts, ShouldEqual, 0)
					switch stream.CodecInfo.Type {
					case Audio:
						So(stream.StreamId, ShouldEqual, 1)
						So(audioStream, ShouldBeNil)
						So(stream.CodecInfo.CodecName, ShouldEqual, "vorbis")
						audioStream = stream
					case Video:
						So(stream.StreamId, ShouldEqual, 0)
						So(videoStream, ShouldBeNil)
						So(stream.CodecInfo.CodecName, ShouldEqual, "theora")
						videoStream = stream
					}
				}
			}
			So(err, ShouldBeNil)

			audioReader := audioStream.Sub()
			videoReader := videoStream.Sub()

			var videoN, audioN int64
			var videoErr, audioErr error

			var wg sync.WaitGroup
			wg.Add(2)
			go func() {
				audioN, audioErr = io.Copy(ioutil.Discard, audioReader)
				wg.Done()
			}()
			go func() {
				videoN, videoErr = io.Copy(ioutil.Discard, videoReader)
				wg.Done()
			}()
			wg.Wait()

			t.Log("Audio read:", audioN)
			t.Log("Video read:", videoN)

			So(audioErr, ShouldBeNil)
			So(audioN, ShouldBeGreaterThan, 0)
			So(videoErr, ShouldBeNil)
			So(videoN, ShouldBeGreaterThan, 0)
		})
	})
}