fixed a bug

2026-09-09 12:31:05 +08:00
parent fb64343a9f
commit 9d956183c7
5 changed files with 185 additions and 9 deletions
--- a/ios/OralTrainer/Player/PlayerController.swift
+++ b/ios/OralTrainer/Player/PlayerController.swift
@@ -26,6 +26,8 @@ final class PlayerController: ObservableObject {
    private var swipeBackAnchorTime: TimeInterval = 0
    private var speedBeforeLongPress: Float?
    private var transientTask: Task<Void, Never>?
+    private var sentenceEndTimeObserver: Any?
+    private var sentenceEndGuardToken = 0

    private static let swipeBackPhaseTimeout: TimeInterval = 1.2
    /// AVPlayer 在个别句子边界会把 seek 结果上报得比目标早 1ms 左右。
@@ -40,6 +42,7 @@ final class PlayerController: ObservableObject {
    init() {
        configureAudioSession()
        player.automaticallyWaitsToMinimizeStalling = true
+        player.actionAtItemEnd = .pause
        timeObserver = player.addPeriodicTimeObserver(
            forInterval: CMTime(seconds: 0.25, preferredTimescale: 600),
            queue: .main
@@ -55,6 +58,7 @@ final class PlayerController: ObservableObject {
        }
        timeControlObserver = player.observe(\.timeControlStatus, options: [.new]) { [weak self] _, _ in
            DispatchQueue.main.async {
+                self?.refreshSentenceBoundaryGuard()
                self?.tick()
            }
        }
@@ -68,6 +72,7 @@ final class PlayerController: ObservableObject {
        if let endObserver = endObserver {
            NotificationCenter.default.removeObserver(endObserver)
        }
+        cancelSentenceBoundaryGuard()
        itemStatusObserver?.invalidate()
        timeControlObserver?.invalidate()
    }
@@ -75,6 +80,7 @@ final class PlayerController: ObservableObject {
    // MARK: - 装载

    func load(_ item: TrainingMediaItem) {
+        cancelSentenceBoundaryGuard()
        lastSentenceIndex = nil
        swipeBackAnchorIndex = nil
        pendingSeekPositionMs = nil
@@ -96,11 +102,15 @@ final class PlayerController: ObservableObject {

    func play() {
        player.play()
+        // play() 可能在 AVPlayer 还没有把 timeControlStatus 切到 playing 前被调用；
+        // 立即强制注册一次，避免最初的几十毫秒没有被句尾守卫覆盖。
+        refreshSentenceBoundaryGuard(force: true)
    }

    func pause() {
        stopAtSentenceEnd = false
        stopAtSentenceEndIndex = nil
+        cancelSentenceBoundaryGuard()
        player.pause()
    }

@@ -119,6 +129,7 @@ final class PlayerController: ObservableObject {
    func stop() {
        stopAtSentenceEnd = false
        stopAtSentenceEndIndex = nil
+        cancelSentenceBoundaryGuard()
        player.pause()
        seek(to: .zero)
    }
@@ -270,10 +281,12 @@ final class PlayerController: ObservableObject {

    func setContinuousPlayback(_ enabled: Bool) {
        config.continuousPlayback = enabled
+        refreshSentenceBoundaryGuard()
    }

    func setSentenceMode(_ enabled: Bool) {
        config.sentenceMode = enabled
+        refreshSentenceBoundaryGuard()
    }

    func setLoopMode(_ mode: LoopMode) {
@@ -412,7 +425,7 @@ final class PlayerController: ObservableObject {

    /// AVPlayer 的 seek 是异步的；所有 seek 必须统一走这里，避免播放循环、
    /// 用户手势和 seek 完成回调交错后把位置拉回旧句子。
-    private func performSeek(to positionMs: Int64) {
+    private func performSeek(to positionMs: Int64, completion: (() -> Void)? = nil) {
        let targetPositionMs = max(0, positionMs)
        seekGeneration += 1
        let generation = seekGeneration
@@ -428,8 +441,10 @@ final class PlayerController: ObservableObject {
                }
                self.pendingSeekPositionMs = nil
                self.tick()
+                completion?()
            }
        }
+        refreshSentenceBoundaryGuard()
        tick()
    }

@@ -518,8 +533,122 @@ final class PlayerController: ObservableObject {
        }
    }

-    private func seekRaw(_ positionMs: Int64) {
-        performSeek(to: positionMs)
+    private func seekRaw(_ positionMs: Int64, completion: (() -> Void)? = nil) {
+        performSeek(to: positionMs, completion: completion)
+    }
+
+    /// AVPlayer 的 periodic observer 间隔是 250ms。仅靠它回收句尾时，
+    /// 最坏情况已经播进下一句约 250ms。这里参照安卓端 PlayerMessage 的做法，
+    /// 在当前句 endMs 精确注册 boundary observer，到点立即执行句尾动作。
+    private func refreshSentenceBoundaryGuard(force: Bool = false) {
+        cancelSentenceBoundaryGuard()
+        guard config.sentenceMode,
+              let item = mediaItem,
+              !item.sentences.isEmpty else {
+            clearForwardPlaybackEnd()
+            return
+        }
+        guard force || isActivelyPlaying() else {
+            return
+        }
+
+        guard let sentence = sentenceBoundaryTarget(in: item) else {
+            clearForwardPlaybackEnd()
+            return
+        }
+        let currentPosition = referencePositionMs()
+        if currentPosition >= sentence.endMs {
+            applySentenceEndAction(sentence)
+            return
+        }
+
+        let token = sentenceEndGuardToken
+        let endTime = CMTime(value: CMTimeValue(sentence.endMs), timescale: 1000)
+        // boundary observer 负责回到句首；forwardPlaybackEndTime 是解码层硬边界，
+        // 即使主线程回调稍晚，AVPlayer 也不会继续渲染 endMs 之后的内容。
+        player.currentItem?.forwardPlaybackEndTime = endTime
+        sentenceEndTimeObserver = player.addBoundaryTimeObserver(
+            forTimes: [NSValue(time: endTime)],
+            queue: .main
+        ) { [weak self] in
+            guard let self, token == self.sentenceEndGuardToken else {
+                return
+            }
+            self.applySentenceEndAction(sentence)
+        }
+    }
+
+    private func cancelSentenceBoundaryGuard() {
+        sentenceEndGuardToken += 1
+        if let observer = sentenceEndTimeObserver {
+            player.removeTimeObserver(observer)
+        }
+        sentenceEndTimeObserver = nil
+    }
+
+    private func clearForwardPlaybackEnd() {
+        player.currentItem?.forwardPlaybackEndTime = .invalid
+    }
+
+    private func isActivelyPlaying() -> Bool {
+        player.timeControlStatus == .playing
+            || player.timeControlStatus == .waitingToPlayAtSpecifiedRate
+    }
+
+    private func sentenceBoundaryTarget(in item: TrainingMediaItem) -> SentenceBoundary? {
+        if stopAtSentenceEnd {
+            guard let index = stopAtSentenceEndIndex else {
+                return nil
+            }
+            return item.sentences.first(where: { $0.index == index })
+        }
+        if config.continuousPlayback {
+            return nil
+        }
+        if let index = lastSentenceIndex ?? currentSentence?.index,
+           let sentence = item.sentences.first(where: { $0.index == index }) {
+            return sentence
+        }
+
+        let position = referencePositionMs()
+        if let sentence = sentence(at: position) {
+            return sentence
+        }
+        return item.sentences.last(where: { $0.startMs <= position })
+    }
+
+    private func applySentenceEndAction(_ target: SentenceBoundary) {
+        cancelSentenceBoundaryGuard()
+        guard let item = mediaItem,
+              let sentence = item.sentences.first(where: { $0.index == target.index }) else {
+            return
+        }
+        lastSentenceIndex = sentence.index
+
+        if stopAtSentenceEnd, stopAtSentenceEndIndex == sentence.index {
+            stopAtSentenceEnd = false
+            stopAtSentenceEndIndex = nil
+            player.pause()
+            seekRaw(sentenceSeekPosition(sentence))
+            tick()
+            return
+        }
+        if config.continuousPlayback {
+            clearForwardPlaybackEnd()
+            return
+        }
+
+        // forwardPlaybackEndTime 到点后 AVPlayer 会自动暂停。这里先回到句首，
+        // 等 seek 完成后再恢复播放，实现同一句循环且不混入下一句内容。
+        player.pause()
+        seekRaw(sentenceSeekPosition(sentence)) { [weak self] in
+            guard let self else {
+                return
+            }
+            self.player.play()
+            self.refreshSentenceBoundaryGuard(force: true)
+            self.tick()
+        }
    }

    private func sentenceSeekPosition(_ sentence: SentenceBoundary) -> Int64 {
@@ -537,11 +666,47 @@ final class PlayerController: ObservableObject {
            tick()
            return
        }
+        // 句尾守卫已经发起“回到句首”的 seek 时，这个通知只是硬边界的附带通知，
+        // 不能再被识别成整条视频结束。
+        guard pendingSeekPositionMs == nil else {
+            tick()
+            return
+        }
+        // 若最后一个句子的 endMs 就是视频末尾，forwardPlaybackEndTime 和自然结束
+        // 是同一时间点。此时必须执行“当前句”的句尾动作，而不能整条视频回零。
+        if config.sentenceMode,
+           !config.continuousPlayback,
+           let sentence = currentSentence,
+           currentPositionMs() + 30 >= sentence.endMs {
+            applySentenceEndAction(sentence)
+            return
+        }
+        // 自定义 forwardPlaybackEndTime 到达时也会发布 didPlayToEndTime。
+        // 这时不能当成整条视频结束回到 0；句尾守卫会马上回到当前句。
+        guard isNaturalMediaEnd() else {
+            tick()
+            return
+        }
        performSeek(to: .zero)
        player.play()
        tick()
    }

+    private func isNaturalMediaEnd() -> Bool {
+        guard let item = player.currentItem else {
+            return true
+        }
+        let durationMs = durationMs(of: item)
+        let positionMs = currentPositionMs()
+        if durationMs > 0 {
+            return positionMs + 30 >= durationMs
+        }
+        guard let sentence = currentSentence else {
+            return true
+        }
+        return positionMs + 30 >= sentence.endMs
+    }
+
    // MARK: - 观察器

    private func attachItemObservers(to item: AVPlayerItem) {