seek to correct position when switching players

backend/playbackengine.go

@@ -171,10 +171,7 @@ func (p *playbackEngine) SetPlayer(pl player.BasePlayer) error {
 	p.registerPlayerCallbacks(pl)
 
 	if needToUnpause {
-		p.PlayTrackAt(p.nowPlayingIdx)
+		p.playTrackAt(p.nowPlayingIdx, p.pendingPlayerChangeTimePos)
-		// TODO - find a better way to wait until the players are ready
-		time.Sleep(200 * time.Millisecond)
-		p.SeekSeconds(p.pendingPlayerChangeTimePos)
 		p.pendingPlayerChange = false
 	}
 	p.invokeNoArgCallbacks(p.onPlayerChange)
@@ -188,6 +185,10 @@ func (p *playbackEngine) SetPlayer(pl player.BasePlayer) error {
 }
 
 func (p *playbackEngine) PlayTrackAt(idx int) error {
+	return p.playTrackAt(idx, 0)
+}
+
+func (p *playbackEngine) playTrackAt(idx int, startTime float64) error {
 	if idx < 0 || idx >= len(p.playQueue) {
 		return errors.New("track index out of range")
 	}
@@ -195,7 +196,7 @@ func (p *playbackEngine) PlayTrackAt(idx int) error {
 	p.checkScrobble()
 	p.alreadyScrobbled = true
 	p.pendingTrackChangeNum = idx
-	err := p.setTrack(idx, false)
+	err := p.setTrack(idx, false, startTime)
 	return err
 }
 
@@ -475,7 +476,7 @@ func (p *playbackEngine) RemoveTracksFromQueue(idxs []int) {
 			p.Stop()
 		} else {
 			p.nowPlayingIdx -= 1 // will be incremented in newtrack callback from player
-			p.setTrack(newNowPlaying, false)
+			p.setTrack(newNowPlaying, false, 0)
 		}
 		// setNextTrack and onSongChange callbacks will be handled
 		// when we receive new track event from player
@@ -617,7 +618,7 @@ func (p *playbackEngine) setNextTrackAfterQueueUpdate() {
 	}
 }
 
-func (p *playbackEngine) setTrack(idx int, next bool) error {
+func (p *playbackEngine) setTrack(idx int, next bool, startTime float64) error {
 	if urlP, ok := p.player.(player.URLPlayer); ok {
 		url := ""
 		var meta mediaprovider.MediaItemMetadata
@@ -637,7 +638,7 @@ func (p *playbackEngine) setTrack(idx int, next bool) error {
 		if next {
 			return urlP.SetNextFile(url, meta)
 		}
-		return urlP.PlayFile(url, meta)
+		return urlP.PlayFile(url, meta, startTime)
 	} else if trP, ok := p.player.(player.TrackPlayer); ok {
 		var track *mediaprovider.Track
 		if idx >= 0 {
@@ -649,13 +650,13 @@ func (p *playbackEngine) setTrack(idx int, next bool) error {
 		if next {
 			return trP.SetNextTrack(track)
 		}
-		return trP.PlayTrack(track)
+		return trP.PlayTrack(track, startTime)
 	}
 	panic("Unsupported player type")
 }
 
 func (p *playbackEngine) setNextTrack(idx int) error {
-	return p.setTrack(idx, true)
+	return p.setTrack(idx, true, 0)
 }
 
 // call BEFORE updating p.nowPlayingIdx

backend/player/dlna/dlnaplayer.go

@@ -123,7 +123,7 @@ func (d *DLNAPlayer) GetVolume() int {
 	return vol
 }
 
-func (d *DLNAPlayer) PlayFile(urlstr string, meta mediaprovider.MediaItemMetadata) error {
+func (d *DLNAPlayer) PlayFile(urlstr string, meta mediaprovider.MediaItemMetadata, startTime float64) error {
 	d.ensureSetupProxy()
 
 	d.metaLock.Lock()
@@ -139,13 +139,23 @@ func (d *DLNAPlayer) PlayFile(urlstr string, meta mediaprovider.MediaItemMetadat
 	if err := d.playAVTransportMedia(&media); err != nil {
 		return err
 	}
+	if startTime > 0 {
+		// TODO: do something better than this!!
+		time.Sleep(2 * time.Second)
+		d.sendSeekCmd(startTime)
+	}
 	d.state = playing
-	d.setTrackChangeTimer(time.Duration(meta.Duration) * time.Second)
+	remainingDur := meta.Duration - int(startTime)
+	d.setTrackChangeTimer(time.Duration(remainingDur) * time.Second)
 	d.stopwatch.Reset()
 	d.stopwatch.Start()
-	d.lastStartTime = 0
+	d.lastStartTime = int(startTime)
 	d.InvokeOnPlaying()
 	d.InvokeOnTrackChange()
+	if startTime > 0 {
+		d.InvokeOnSeek()
+	}
+
 	return nil
 }
 
@@ -251,12 +261,9 @@ func (d *DLNAPlayer) SeekSeconds(secs float64) error {
 		d.pendingSeek = true
 		d.pendingSeekSecs = secs
 	} else {
-		d.seeking = true
+		if err := d.sendSeekCmd(secs); err != nil {
-		if err := d.avTransport.Seek(context.Background(), int(secs)); err != nil {
-			d.seeking = false
 			return err
 		}
-		d.seeking = false
 	}
 
 	d.lastStartTime = int(secs)
@@ -274,6 +281,16 @@ func (d *DLNAPlayer) SeekSeconds(secs float64) error {
 	return nil
 }
 
+func (d *DLNAPlayer) sendSeekCmd(secs float64) error {
+	d.seeking = true
+	if err := d.avTransport.Seek(context.Background(), int(secs)); err != nil {
+		d.seeking = false
+		return err
+	}
+	d.seeking = false
+	return nil
+}
+
 func (d *DLNAPlayer) IsSeeking() bool {
 	return d.seeking
 }

backend/player/jukebox/jukeboxplayer.go

@@ -80,7 +80,7 @@ func (j *JukeboxPlayer) Stop() error {
 	return nil
 }
 
-func (j *JukeboxPlayer) PlayTrack(track *mediaprovider.Track) error {
+func (j *JukeboxPlayer) PlayTrack(track *mediaprovider.Track, _ float64) error {
 	if err := j.provider.JukeboxSet(track.ID); err != nil {
 		return err
 	}

backend/player/mpv/player.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math"
 	"strconv"
+	"sync"
 
 	"github.com/dweymouth/supersonic/backend/mediaprovider"
 	"github.com/dweymouth/supersonic/backend/player"
@@ -68,6 +69,9 @@ type Player struct {
 	equalizer      Equalizer
 	peaksEnabled   bool
 
+	fileLoadedLock sync.Mutex
+	fileLoadedSig  *sync.Cond
+
 	bgCancel context.CancelFunc
 }
 
@@ -80,10 +84,12 @@ func New() *Player {
 // Same as New, but sets the application name that mpv
 // reports to the system audio API.
 func NewWithClientName(c string) *Player {
-	return &Player{
+	p := &Player{
 		vol:        -1, // use 100 in Init
 		clientName: c,
 	}
+	p.fileLoadedSig = sync.NewCond(&p.fileLoadedLock)
+	return p
 }
 
 // Initializes the Player and makes it ready for playback.
@@ -134,18 +140,27 @@ func (p *Player) Init(maxCacheMB int) error {
 }
 
 // Plays the specified file, clearing the previous play queue, if any.
-func (p *Player) PlayFile(url string, _ mediaprovider.MediaItemMetadata) error {
+func (p *Player) PlayFile(url string, _ mediaprovider.MediaItemMetadata, startTime float64) error {
 	if !p.initialized {
 		return ErrUnitialized
 	}
 	err := p.mpv.Command([]string{"loadfile", url, "replace"})
-	if err == nil {
+	if err != nil {
+		return err
+	}
 	p.lenPlaylist = 1
 	if p.status.State == player.Paused {
-			return p.Continue()
+		err = p.Continue()
-		}
+	} else {
 		p.setState(player.Playing)
 	}
+	if startTime > 0 {
+		p.fileLoadedLock.Lock()
+		p.fileLoadedSig.Wait()
+		p.fileLoadedLock.Unlock()
+		p.SeekSeconds(startTime)
+	}
+
 	return err
 }
 
@@ -481,10 +496,9 @@ func (p *Player) eventHandler(ctx context.Context) {
 			}
 			switch e.Event_Id {
 			case mpv.EVENT_PLAYBACK_RESTART:
-				if p.seeking {
 				p.seeking = false
-				}
 			case mpv.EVENT_SEEK:
+				p.seeking = false
 				p.InvokeOnSeek()
 			case mpv.EVENT_FILE_LOADED:
 				p.curPlaylistPos, _ = p.getInt64Property("playlist-pos")
@@ -494,6 +508,7 @@ func (p *Player) eventHandler(ctx context.Context) {
 					p.InvokeOnSeek()
 				}
 				p.InvokeOnTrackChange()
+				p.fileLoadedSig.Signal()
 			case mpv.EVENT_IDLE:
 				p.status.Duration = 0
 				p.status.TimePos = 0

backend/player/player.go

@@ -4,13 +4,13 @@ import "github.com/dweymouth/supersonic/backend/mediaprovider"
 
 type URLPlayer interface {
 	BasePlayer
-	PlayFile(url string, metadata mediaprovider.MediaItemMetadata) error
+	PlayFile(url string, metadata mediaprovider.MediaItemMetadata, startTime float64) error
 	SetNextFile(url string, metadata mediaprovider.MediaItemMetadata) error
 }
 
 type TrackPlayer interface {
 	BasePlayer
-	PlayTrack(track *mediaprovider.Track) error
+	PlayTrack(track *mediaprovider.Track, startTime float64) error
 	SetNextTrack(track *mediaprovider.Track) error
 }