Revert "refactor play count update to be cleaner, code-wise"

This reverts commit cd52a893d4, which introduced a regression.
Pages with a tracklist may not have the same in-memory model of the track,
so it is necessary to directly inform them of play count updates.

backend/playbackmanager.go

@@ -28,7 +28,10 @@ type PlaybackManager struct {
 	playQueue     []*subsonic.Child
 	nowPlayingIdx int64
 
-	onSongChange     []func(nowPlaying *subsonic.Child)
+	// to pass to onSongChange listeners; clear once listeners have been called
+	lastScrobbled *subsonic.Child
+
+	onSongChange     []func(nowPlaying *subsonic.Child, justScrobbledIfAny *subsonic.Child)
 	onPlayTimeUpdate []func(float64, float64)
 }
 
@@ -95,7 +98,7 @@ func (p *PlaybackManager) NowPlaying() *subsonic.Child {
 }
 
 // Sets a callback that is notified whenever a new song begins playing.
-func (p *PlaybackManager) OnSongChange(cb func(nowPlaying *subsonic.Child)) {
+func (p *PlaybackManager) OnSongChange(cb func(nowPlaying *subsonic.Child, justScrobbledIfAny *subsonic.Child)) {
 	p.onSongChange = append(p.onSongChange, cb)
 }
 
@@ -225,15 +228,16 @@ func (p *PlaybackManager) checkScrobble(playDur time.Duration) {
 	song := p.playQueue[p.nowPlayingIdx]
 	if playDur.Seconds()/p.curTrackTime > ScrobbleThreshold {
 		log.Printf("Scrobbling %q", song.Title)
-		song.PlayCount += 1
+		p.lastScrobbled = song
 		p.sm.Server.Scrobble(song.ID, map[string]string{"time": strconv.FormatInt(time.Now().Unix()*1000, 10)})
 	}
 }
 
 func (p *PlaybackManager) invokeOnSongChangeCallbacks() {
 	for _, cb := range p.onSongChange {
-		cb(p.NowPlaying())
+		cb(p.NowPlaying(), p.lastScrobbled)
 	}
+	p.lastScrobbled = nil
 }
 
 func (p *PlaybackManager) startPollTimePos() {

ui/bottompanel.go

@@ -84,7 +84,7 @@ func (bp *BottomPanel) SetPlaybackManager(pm *backend.PlaybackManager) {
 	})
 }
 
-func (bp *BottomPanel) onSongChange(song *subsonic.Child) {
+func (bp *BottomPanel) onSongChange(song *subsonic.Child, _ *subsonic.Child) {
 	if song == nil {
 		bp.NowPlaying.Update("", "", "", nil)
 	} else {

ui/browsing/albumpage.go

@@ -100,15 +100,14 @@ func (a *AlbumPage) Route() Route {
 	return AlbumRoute(a.albumID)
 }
 
-var _ CanShowNowPlaying = (*AlbumPage)(nil)
+func (a *AlbumPage) OnSongChange(song *subsonic.Child, lastScrobbledIfAny *subsonic.Child) {
-
-func (a *AlbumPage) OnSongChange(song *subsonic.Child) {
 	if song == nil {
 		a.nowPlayingID = ""
 	} else {
 		a.nowPlayingID = song.ID
 	}
 	a.tracklist.SetNowPlaying(a.nowPlayingID)
+	a.tracklist.IncrementPlayCount(lastScrobbledIfAny)
 }
 
 func (a *AlbumPage) Reload() {

ui/browsing/browsingpane.go

@@ -36,7 +36,7 @@ type CanSelectAll interface {
 }
 
 type CanShowNowPlaying interface {
-	OnSongChange(song *subsonic.Child)
+	OnSongChange(song *subsonic.Child, lastScrobbledIfAny *subsonic.Child)
 }
 
 type BrowsingPane struct {
@@ -150,7 +150,7 @@ func (b *BrowsingPane) doSetPage(p Page) bool {
 	b.curPage = p
 	if np, ok := p.(CanShowNowPlaying); ok {
 		// inform page of currently playing track
-		np.OnSongChange(b.app.PlaybackManager.NowPlaying())
+		np.OnSongChange(b.app.PlaybackManager.NowPlaying(), nil)
 	}
 	b.pageContainer.Remove(b.curPage)
 	b.pageContainer.Objects[1] = p
@@ -158,12 +158,12 @@ func (b *BrowsingPane) doSetPage(p Page) bool {
 	return true
 }
 
-func (b *BrowsingPane) onSongChange(song *subsonic.Child) {
+func (b *BrowsingPane) onSongChange(song *subsonic.Child, lastScrobbledIfAny *subsonic.Child) {
 	if b.curPage == nil {
 		return
 	}
 	if p, ok := b.curPage.(CanShowNowPlaying); ok {
-		p.OnSongChange(song)
+		p.OnSongChange(song, lastScrobbledIfAny)
 	}
 }
 

ui/browsing/nowplayingpage.go

@@ -79,15 +79,14 @@ func (a *NowPlayingPage) SelectAll() {
 	a.tracklist.SelectAll()
 }
 
-var _ CanShowNowPlaying = (*NowPlayingPage)(nil)
+func (a *NowPlayingPage) OnSongChange(song *subsonic.Child, lastScrobbledIfAny *subsonic.Child) {
-
-func (a *NowPlayingPage) OnSongChange(song *subsonic.Child) {
 	if song == nil {
 		a.nowPlayingID = ""
 	} else {
 		a.nowPlayingID = song.ID
 	}
 	a.tracklist.SetNowPlaying(a.nowPlayingID)
+	a.tracklist.IncrementPlayCount(lastScrobbledIfAny)
 }
 
 func (a *NowPlayingPage) Reload() {

ui/browsing/playlistpage.go

@@ -86,15 +86,14 @@ func (a *PlaylistPage) Route() Route {
 	return PlaylistRoute(a.playlistID)
 }
 
-var _ CanShowNowPlaying = (*PlaylistPage)(nil)
+func (a *PlaylistPage) OnSongChange(song *subsonic.Child, lastScrobbledIfAny *subsonic.Child) {
-
-func (a *PlaylistPage) OnSongChange(song *subsonic.Child) {
 	if song == nil {
 		a.nowPlayingID = ""
 	} else {
 		a.nowPlayingID = song.ID
 	}
 	a.tracklist.SetNowPlaying(a.nowPlayingID)
+	a.tracklist.IncrementPlayCount(lastScrobbledIfAny)
 }
 
 func (a *PlaylistPage) Reload() {

ui/mainwindow.go

@@ -64,7 +64,7 @@ func NewMainWindow(fyneApp fyne.App, appName string, app *backend.App, size fyne
 	m.container = container.NewBorder(nil, m.BottomPanel, nil, nil, m.BrowsingPane)
 	m.Window.SetContent(m.container)
 	m.Window.Resize(size)
-	app.PlaybackManager.OnSongChange(func(song *subsonic.Child) {
+	app.PlaybackManager.OnSongChange(func(song *subsonic.Child, _ *subsonic.Child) {
 		if song == nil {
 			m.Window.SetTitle(appName)
 			return

ui/widgets/tracklist.go

@@ -145,6 +145,19 @@ func (t *Tracklist) SetNowPlaying(trackID string) {
 	t.list.Refresh()
 }
 
+func (t *Tracklist) IncrementPlayCount(track *subsonic.Child) {
+	if track == nil {
+		return
+	}
+	for _, tr := range t.Tracks {
+		if tr.ID == track.ID {
+			tr.PlayCount += 1
+			t.Refresh()
+			return
+		}
+	}
+}
+
 func (t *Tracklist) SelectAll() {
 	t.selectionMgr.SelectAll()
 	t.Refresh()
@@ -347,7 +360,8 @@ func NewTrackRow(tracklist *Tracklist, playingIcon fyne.CanvasObject) *TrackRow
 }
 
 func (t *TrackRow) Update(tr *subsonic.Child, isPlaying bool, rowNum int) {
-	if tr.ID != t.trackID {
+	if tr.ID != t.trackID || isPlaying != t.isPlaying || tr.PlayCount != t.playCount {
+		t.isPlaying = isPlaying
 		t.trackID = tr.ID
 		t.playCount = tr.PlayCount
 
@@ -362,15 +376,7 @@ func (t *TrackRow) Update(tr *subsonic.Child, isPlaying bool, rowNum int) {
 		t.year.Segments[0].(*widget.TextSegment).Text = strconv.Itoa(tr.Year)
 		t.plays.Segments[0].(*widget.TextSegment).Text = strconv.Itoa(int(tr.PlayCount))
 		t.bitrate.Segments[0].(*widget.TextSegment).Text = strconv.Itoa(tr.BitRate)
-	}
 
-	if tr.PlayCount != t.playCount {
-		t.playCount = tr.PlayCount
-		t.plays.Segments[0].(*widget.TextSegment).Text = strconv.Itoa(int(tr.PlayCount))
-	}
-
-	if isPlaying != t.isPlaying {
-		t.isPlaying = isPlaying
 		t.name.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
 		t.artist.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
 		t.album.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
@@ -378,6 +384,7 @@ func (t *TrackRow) Update(tr *subsonic.Child, isPlaying bool, rowNum int) {
 		t.year.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
 		t.plays.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
 		t.bitrate.Segments[0].(*widget.TextSegment).Style.TextStyle.Bold = isPlaying
+
 		if isPlaying {
 			t.container.Objects[1].(*fyne.Container).Objects[0] = container.NewCenter(t.playingIcon)
 		} else {