fix: slider jumping after drag issue. Fix player can not play again issue

Mastodon/Scene/Share/ViewModel/AudioContainerViewModel.swift

@@ -20,7 +20,6 @@ class AudioContainerViewModel {
 
         audioView.playButton.publisher(for: .touchUpInside)
             .sink { _ in
-
                 if audioAttachment === AudioPlayer.shared.attachment {
                     if AudioPlayer.shared.isPlaying() {
                         AudioPlayer.shared.pause()
@@ -53,16 +52,26 @@ class AudioContainerViewModel {
         audioAttachment: Attachment
     ) {
         let audioView = cell.statusView.audioView
+        var lastCurrentTimeSubject: TimeInterval?
         AudioPlayer.shared.currentTimeSubject
-            .receive(on: DispatchQueue.main)
-            .filter { _ in
-                audioAttachment === AudioPlayer.shared.attachment
+            .throttle(for: 0.33, scheduler: DispatchQueue.main, latest: true)
+            .compactMap { time -> (TimeInterval, Float)? in
+                defer {
+                    lastCurrentTimeSubject = time
                 }
-            .sink(receiveValue: { time in
+                guard audioAttachment === AudioPlayer.shared.attachment else { return nil }
+                guard let duration = audioAttachment.meta?.original?.duration else { return nil }
+                
+                if let lastCurrentTimeSubject = lastCurrentTimeSubject, time != 0.0 {
+                    guard abs(time - lastCurrentTimeSubject) < 0.5 else { return nil }  // debounce
+                }
+                
+                guard !audioView.slider.isTracking else { return nil }
+                return (time, Float(time / duration))
+            }
+            .sink(receiveValue: { time, progress in
                 audioView.timeLabel.text = time.asString(style: .positional)
-                if let duration = audioAttachment.meta?.original?.duration, !audioView.slider.isTracking {
-                    audioView.slider.setValue(Float(time / duration), animated: true)
-                }
+                audioView.slider.setValue(progress, animated: true)
             })
             .store(in: &cell.disposeBag)
         AudioPlayer.shared.playbackState

Mastodon/Service/AudioPlayer.swift

@@ -18,14 +18,16 @@ final class AudioPlayer: NSObject {
     var timeObserver: Any?
     var statusObserver: Any?
     var attachment: Attachment?
-    var currentURL: URL?
+
     let session = AVAudioSession.sharedInstance()
     let playbackState = CurrentValueSubject<PlaybackState, Never>(PlaybackState.unknown)
+    
+    // MARK: - singleton
     public static let shared = AudioPlayer()
 
     let currentTimeSubject = CurrentValueSubject<TimeInterval, Never>(0)
 
-    override init() {
+    private override init() {
         super.init()
         addObserver()
     }
@@ -45,7 +47,7 @@ extension AudioPlayer {
 
         if audioAttachment == attachment {
             if self.playbackState.value == .stopped {
-                self.seekToTime(time: 0)
+                self.seekToTime(time: .zero)
             }
             player.play()
             self.playbackState.value = .playing
@@ -97,12 +99,14 @@ extension AudioPlayer {
                 case .unknown:
                     self.playbackState.value = .unknown
                 @unknown default:
-                    fatalError()
+                    assertionFailure()
                 }
             })
             .store(in: &disposeBag)
         NotificationCenter.default.publisher(for: .AVPlayerItemDidPlayToEndTime, object: nil)
-            .sink { _ in
+            .sink { [weak self] _ in
+                guard let self = self else { return }
+                self.player.seek(to: .zero)
                 self.playbackState.value = .stopped
                 self.currentTimeSubject.value = 0
             }