#include "utils_synchronizer_v2.h"
#include "../base/logger.h"
#include <algorithm>
#include <cmath>
#include <sstream>
#include <iomanip>

namespace av {
namespace utils {

SynchronizerV2::SynchronizerV2(const SyncConfigV2& config)
    : config_(config)
    , masterClockType_(ClockType::AUDIO)
    , state_(SyncState::IDLE)
    , initialized_(false)
    , running_(false)
    , paused_(false)
    , recoveryAttempts_(0)
    , lastSyncError_(0.0) {
    
    // 初始化时钟
    audioClock_ = ClockInfo();
    videoClock_ = ClockInfo();
    externalClock_ = ClockInfo();
    
    // 初始化历史记录
    audioClockHistory_.clear();
    videoClockHistory_.clear();
    syncErrorHistory_.clear();
    
    Logger::instance().info("SynchronizerV2 created with strategy: " + 
                           std::to_string(static_cast<int>(config_.strategy)));
}

SynchronizerV2::~SynchronizerV2() {
    close();
    Logger::instance().info("SynchronizerV2 destroyed");
}

ErrorCode SynchronizerV2::initialize() {
    if (initialized_) {
        return ErrorCode::ALREADY_INITIALIZED;
    }
    
    std::lock_guard<std::mutex> clockLock(clockMutex_);
    std::lock_guard<std::mutex> statsLock(statsMutex_);
    
    // 重置所有时钟
    resetClock(ClockType::AUDIO);
    resetClock(ClockType::VIDEO);
    resetClock(ClockType::EXTERNAL);
    
    // 选择主时钟
    selectMasterClock();
    
    // 重置统计信息
    stats_ = SyncStatsV2();
    stats_.lastUpdateTime = std::chrono::steady_clock::now();
    
    // 设置开始时间
    startTime_ = std::chrono::steady_clock::now();
    lastClockUpdate_ = startTime_;
    lastStatsUpdate_ = startTime_;
    
    state_ = SyncState::IDLE;
    initialized_ = true;
    recoveryAttempts_ = 0;
    
    Logger::instance().info("SynchronizerV2 initialized");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::start() {
    if (!initialized_) {
        return ErrorCode::NOT_INITIALIZED;
    }
    
    if (running_) {
        return ErrorCode::ALREADY_STARTED;
    }
    
    running_ = true;
    paused_ = false;
    state_ = SyncState::INITIALIZING;
    
    startTime_ = std::chrono::steady_clock::now();
    lastClockUpdate_ = startTime_;
    
    // 启动后立即进入同步状态
    state_ = SyncState::SYNCING;
    
    Logger::instance().info("SynchronizerV2 started");
    return ErrorCode::SUCCESS;
}

void SynchronizerV2::setStreamInfo(bool hasAudio, bool hasVideo) {
    std::lock_guard<std::mutex> lock(clockMutex_);
    hasAudioStream_ = hasAudio;
    hasVideoStream_ = hasVideo;
    
    Logger::instance().info("Stream info updated: hasAudio=" + std::to_string(hasAudio) + 
                           ", hasVideo=" + std::to_string(hasVideo));
    
    // 重新选择主时钟
    selectMasterClock();
}

ErrorCode SynchronizerV2::stop() {
    if (!running_) {
        return ErrorCode::NOT_STARTED;
    }
    
    running_ = false;
    paused_ = false;
    state_ = SyncState::IDLE;
    
    Logger::instance().info("SynchronizerV2 stopped");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::pause() {
    if (!running_) {
        return ErrorCode::NOT_STARTED;
    }
    
    if (paused_) {
        return ErrorCode::ALREADY_PAUSED;
    }
    
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    paused_ = true;
    
    // 暂停所有时钟
    pauseClock(ClockType::AUDIO, true);
    pauseClock(ClockType::VIDEO, true);
    pauseClock(ClockType::EXTERNAL, true);
    
    Logger::instance().info("SynchronizerV2 paused");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::resume() {
    if (!running_) {
        return ErrorCode::NOT_STARTED;
    }
    
    if (!paused_) {
        return ErrorCode::NOT_PAUSED;
    }
    
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    paused_ = false;
    
    // 恢复所有时钟
    pauseClock(ClockType::AUDIO, false);
    pauseClock(ClockType::VIDEO, false);
    pauseClock(ClockType::EXTERNAL, false);
    
    state_ = SyncState::SYNCING;
    
    Logger::instance().info("SynchronizerV2 resumed");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::reset() {
    std::lock_guard<std::mutex> clockLock(clockMutex_);
    std::lock_guard<std::mutex> statsLock(statsMutex_);
    std::lock_guard<std::mutex> historyLock(historyMutex_);
    
    // 重置时钟
    resetClock(ClockType::AUDIO);
    resetClock(ClockType::VIDEO);
    resetClock(ClockType::EXTERNAL);
    
    // 重置统计信息
    stats_ = SyncStatsV2();
    stats_.lastUpdateTime = std::chrono::steady_clock::now();
    
    // 清空历史记录
    audioClockHistory_.clear();
    videoClockHistory_.clear();
    syncErrorHistory_.clear();
    
    // 重置状态
    state_ = running_ ? SyncState::SYNCING : SyncState::IDLE;
    recoveryAttempts_ = 0;
    lastSyncError_ = 0.0;
    
    // 重新选择主时钟
    selectMasterClock();
    
    Logger::instance().info("SynchronizerV2 reset");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::close() {
    if (running_) {
        stop();
    }
    
    initialized_ = false;
    
    Logger::instance().info("SynchronizerV2 closed");
    return ErrorCode::SUCCESS;
}

ErrorCode SynchronizerV2::setAudioClock(double pts, double time, int serial) {
    return updateClock(ClockType::AUDIO, pts, time, serial);
}

ErrorCode SynchronizerV2::setVideoClock(double pts, double time, int serial) {
    return updateClock(ClockType::VIDEO, pts, time, serial);
}

ErrorCode SynchronizerV2::setExternalClock(double time, int serial) {
    if (time < 0) {
        time = getCurrentTime();
    }
    return updateClock(ClockType::EXTERNAL, time, time, serial);
}

double SynchronizerV2::getAudioClock(bool predict) const {
    return getClock(ClockType::AUDIO, predict);
}

double SynchronizerV2::getVideoClock(bool predict) const {
    return getClock(ClockType::VIDEO, predict);
}

double SynchronizerV2::getExternalClock(bool predict) const {
    return getClock(ClockType::EXTERNAL, predict);
}

double SynchronizerV2::getMasterClock(bool predict) const {
    return getClock(masterClockType_, predict);
}

FrameDecision SynchronizerV2::shouldDisplayVideoFrame(double pts, double duration) {
    FrameDecision decision;
    decision.actualPts = pts;
    
    if (!running_ || paused_) {
        decision.action = FrameAction::DELAY;
        decision.delay = 0.01; // 10ms
        decision.reason = paused_ ? "Paused" : "Not running";
        return decision;
    }
    
    // 获取主时钟
    double masterClock = getMasterClock(true); // 使用预测
    decision.targetPts = masterClock;
    
    // 计算同步误差
    double syncError = pts - masterClock;
    decision.syncError = syncError;
    
    // 如果视频是主时钟，直接显示
    if (masterClockType_ == ClockType::VIDEO) {
        decision.action = FrameAction::DISPLAY;
        decision.delay = duration > 0 ? duration : (1.0 / 25.0); // 默认25fps
        decision.reason = "Video master";
        return decision;
    }
    
    // 根据同步误差决定动作
    if (syncError < -config_.frameDropThreshold) {
        // 视频太慢，丢帧
        decision.action = FrameAction::DROP;
        decision.reason = "Video too slow, drop frame";
        
        // 通知丢帧
        if (frameDropCallback_) {
            frameDropCallback_(ClockType::VIDEO, pts);
        }
        
        // 更新统计
        std::lock_guard<std::mutex> lock(statsMutex_);
        stats_.droppedFrames++;
        
    } else if (syncError > config_.frameDupThreshold) {
        // 视频太快，重复帧或延迟
        if (duration > 0 && syncError < config_.frameDupThreshold * 2) {
            decision.action = FrameAction::DELAY;
            decision.delay = std::min(syncError, config_.maxSyncError);
            decision.reason = "Video too fast, delay";
        } else {
            decision.action = FrameAction::Frame_DUPLICATE;
            decision.reason = "Video too fast, duplicate frame";
            
            // 通知重复帧
            if (frameDuplicateCallback_) {
                frameDuplicateCallback_(ClockType::VIDEO, pts);
            }
            
            // 更新统计
            std::lock_guard<std::mutex> lock(statsMutex_);
            stats_.duplicatedFrames++;
        }
        
    } else {
        // 正常显示
        decision.action = FrameAction::DISPLAY;
        decision.delay = calculateTargetDelay(pts, ClockType::VIDEO);
        decision.reason = "Normal display";
    }
    
    // 更新统计
    {
        std::lock_guard<std::mutex> lock(statsMutex_);
        stats_.totalFrames++;
        stats_.syncError = syncError;
        
        // 更新平均同步误差
        if (stats_.totalFrames == 1) {
            stats_.avgSyncError = std::abs(syncError);
        } else {
            stats_.avgSyncError = stats_.avgSyncError * 0.9 + std::abs(syncError) * 0.1;
        }
        
        // 更新最大同步误差
        stats_.maxSyncError = std::max(stats_.maxSyncError, std::abs(syncError));
    }
    
    return decision;
}

FrameDecision SynchronizerV2::shouldPlayAudioFrame(double pts, double duration) {
    FrameDecision decision;
    decision.actualPts = pts;
    
    if (!running_ || paused_) {
        decision.action = FrameAction::DELAY;
        decision.delay = 0.01; // 10ms
        decision.reason = paused_ ? "Paused" : "Not running";
        return decision;
    }
    
    // 音频通常作为主时钟，或者需要与主时钟同步
    if (masterClockType_ == ClockType::AUDIO) {
        decision.action = FrameAction::DISPLAY;
        decision.delay = duration > 0 ? duration : 0.023; // 默认23ms (44.1kHz, 1024 samples)
        decision.reason = "Audio master";
        decision.targetPts = pts;
        return decision;
    }
    
    // 与主时钟同步
    double masterClock = getMasterClock(true);
    decision.targetPts = masterClock;
    
    double syncError = pts - masterClock;
    decision.syncError = syncError;
    
    if (std::abs(syncError) > config_.maxSyncError) {
        // 同步误差太大，丢弃或延迟
        if (syncError < 0) {
            decision.action = FrameAction::DROP;
            decision.reason = "Audio too slow, drop";
        } else {
            decision.action = FrameAction::DELAY;
            decision.delay = std::min(syncError, config_.maxSyncError);
            decision.reason = "Audio too fast, delay";
        }
    } else {
        decision.action = FrameAction::DISPLAY;
        decision.delay = calculateTargetDelay(pts, ClockType::AUDIO);
        decision.reason = "Normal audio play";
    }
    
    return decision;
}

double SynchronizerV2::calculateTargetDelay(double pts, ClockType clockType) {
    if (!running_) {
        return 0.0;
    }
    
    // 基础延迟
    double baseDelay = 0.0;
    if (clockType == ClockType::VIDEO) {
        baseDelay = 1.0 / 25.0; // 默认25fps
    } else if (clockType == ClockType::AUDIO) {
        baseDelay = 0.023; // 默认23ms
    }
    
    // 如果是主时钟，返回基础延迟
    if (clockType == masterClockType_) {
        return baseDelay;
    }
    
    // 计算与主时钟的差异
    double masterClock = getMasterClock(true);
    double diff = pts - masterClock;
    
    // 调整延迟
    double adjustedDelay = baseDelay;
    
    if (std::abs(diff) < config_.syncThreshold) {
        // 在同步阈值内，正常延迟
        adjustedDelay = baseDelay;
    } else if (diff < 0) {
        // 落后于主时钟，减少延迟
        adjustedDelay = std::max(0.0, baseDelay + diff);
    } else {
        // 超前于主时钟，增加延迟
        adjustedDelay = baseDelay + std::min(diff, config_.maxSyncError);
    }
    
    return adjustedDelay;
}

bool SynchronizerV2::shouldDropFrame(double pts, ClockType clockType) {
    if (!running_ || clockType == masterClockType_) {
        return false;
    }
    
    double masterClock = getMasterClock();
    double diff = pts - masterClock;
    
    return diff < -config_.frameDropThreshold;
}

bool SynchronizerV2::shouldDuplicateFrame(double pts, ClockType clockType) {
    if (!running_ || clockType == masterClockType_) {
        return false;
    }
    
    double masterClock = getMasterClock();
    double diff = pts - masterClock;
    
    return diff > config_.frameDupThreshold;
}

double SynchronizerV2::calculateSyncError() const {
    if (!running_) {
        return 0.0;
    }
    
    double audioClock = getAudioClock();
    double videoClock = getVideoClock();
    
    if (audioClock <= 0 || videoClock <= 0) {
        return 0.0;
    }
    
    return std::abs(audioClock - videoClock);
}

// 内部版本，假设调用者已经持有clockMutex_锁
double SynchronizerV2::calculateSyncErrorInternal() const {
    if (!running_) {
        return 0.0;
    }
    
    // 直接计算时钟值，避免调用getClock导致死锁
    double audioClock = 0.0;
    double videoClock = 0.0;
    
    // 计算音频时钟
    if (!audioClock_.paused) {
        auto now = std::chrono::steady_clock::now();
        double elapsed = std::chrono::duration<double>(now - audioClock_.lastUpdate).count();
        audioClock = audioClock_.pts + elapsed * audioClock_.speed;
    } else {
        audioClock = audioClock_.pts;
    }
    
    // 计算视频时钟
    if (!videoClock_.paused) {
        auto now = std::chrono::steady_clock::now();
        double elapsed = std::chrono::duration<double>(now - videoClock_.lastUpdate).count();
        videoClock = videoClock_.pts + elapsed * videoClock_.speed;
    } else {
        videoClock = videoClock_.pts;
    }
    
    if (audioClock <= 0 || videoClock <= 0) {
        return 0.0;
    }
    
    return std::abs(audioClock - videoClock);
}

double SynchronizerV2::calculateAudioDelay(double pts) const {
    if (masterClockType_ == ClockType::AUDIO) {
        return 0.0;
    }
    
    double masterClock = getMasterClock();
    return pts - masterClock;
}

double SynchronizerV2::calculateVideoDelay(double pts) const {
    if (masterClockType_ == ClockType::VIDEO) {
        return 0.0;
    }
    
    double masterClock = getMasterClock();
    return pts - masterClock;
}

void SynchronizerV2::setConfig(const SyncConfigV2& config) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_ = config;
    
    // 重新选择主时钟
    selectMasterClock();
    
    Logger::instance().info("SynchronizerV2 config updated");
}

SyncConfigV2 SynchronizerV2::getConfig() const {
    std::lock_guard<std::mutex> lock(configMutex_);
    return config_;
}

void SynchronizerV2::setSyncStrategy(SyncStrategy strategy) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_.strategy = strategy;
    selectMasterClock();
    
    Logger::instance().info("Sync strategy set to: " + std::to_string(static_cast<int>(strategy)));
}

SyncStrategy SynchronizerV2::getSyncStrategy() const {
    std::lock_guard<std::mutex> lock(configMutex_);
    return config_.strategy;
}

void SynchronizerV2::setPlaybackSpeed(double speed) {
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    audioClock_.speed = speed;
    videoClock_.speed = speed;
    externalClock_.speed = speed;
    
    Logger::instance().info("Playback speed set to: " + std::to_string(speed) + "x");
}

double SynchronizerV2::getPlaybackSpeed() const {
    std::lock_guard<std::mutex> lock(clockMutex_);
    return audioClock_.speed;
}

bool SynchronizerV2::isSynchronized() const {
    return state_ == SyncState::SYNCHRONIZED;
}

SyncStatsV2 SynchronizerV2::getStats() const {
    std::lock_guard<std::mutex> lock(statsMutex_);
    SyncStatsV2 stats = stats_;
    
    // 更新当前时钟值
    stats.audioClock = getAudioClock();
    stats.videoClock = getVideoClock();
    stats.externalClock = getExternalClock();
    stats.masterClock = getMasterClock();
    stats.state = state_;
    stats.masterClockType = masterClockType_;
    
    return stats;
}

void SynchronizerV2::resetStats() {
    std::lock_guard<std::mutex> lock(statsMutex_);
    stats_ = SyncStatsV2();
    stats_.lastUpdateTime = std::chrono::steady_clock::now();
    
    Logger::instance().info("SynchronizerV2 stats reset");
}

void SynchronizerV2::setSyncEventCallback(SyncEventCallback callback) {
    syncEventCallback_ = callback;
}

void SynchronizerV2::setFrameDropCallback(FrameDropCallback callback) {
    frameDropCallback_ = callback;
}

void SynchronizerV2::setFrameDuplicateCallback(FrameDuplicateCallback callback) {
    frameDuplicateCallback_ = callback;
}

void SynchronizerV2::setSyncErrorCallback(SyncErrorCallback callback) {
    syncErrorCallback_ = callback;
}

void SynchronizerV2::enableAdaptiveSync(bool enable) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_.enableAdaptiveSync = enable;
    
    Logger::instance().info("Adaptive sync " + std::string(enable ? "enabled" : "disabled"));
}

void SynchronizerV2::enablePrediction(bool enable) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_.enablePrediction = enable;
    
    Logger::instance().info("Prediction " + std::string(enable ? "enabled" : "disabled"));
}

void SynchronizerV2::setClockUpdateInterval(double interval) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_.clockUpdateInterval = interval;
    
    Logger::instance().info("Clock update interval set to: " + std::to_string(interval * 1000) + "ms");
}

void SynchronizerV2::setSmoothingWindow(int window) {
    std::lock_guard<std::mutex> lock(configMutex_);
    config_.smoothingWindow = window;
    
    // 调整历史记录大小
    std::lock_guard<std::mutex> historyLock(historyMutex_);
    while (audioClockHistory_.size() > static_cast<size_t>(window)) {
        audioClockHistory_.pop_front();
    }
    while (videoClockHistory_.size() > static_cast<size_t>(window)) {
        videoClockHistory_.pop_front();
    }
    while (syncErrorHistory_.size() > static_cast<size_t>(window)) {
        syncErrorHistory_.pop_front();
    }
    
    Logger::instance().info("Smoothing window set to: " + std::to_string(window));
}

std::string SynchronizerV2::getDebugInfo() const {
    std::ostringstream oss;
    
    SyncStatsV2 stats = getStats();
    
    oss << std::fixed << std::setprecision(3);
    oss << "SynchronizerV2 Debug Info:\n";
    oss << "  State: " << static_cast<int>(stats.state) << "\n";
    oss << "  Master Clock: " << static_cast<int>(stats.masterClockType) << "\n";
    oss << "  Audio Clock: " << stats.audioClock << "s\n";
    oss << "  Video Clock: " << stats.videoClock << "s\n";
    oss << "  External Clock: " << stats.externalClock << "s\n";
    oss << "  Master Clock: " << stats.masterClock << "s\n";
    oss << "  Sync Error: " << stats.syncError * 1000 << "ms\n";
    oss << "  Avg Sync Error: " << stats.avgSyncError * 1000 << "ms\n";
    oss << "  Max Sync Error: " << stats.maxSyncError * 1000 << "ms\n";
    oss << "  Total Frames: " << stats.totalFrames << "\n";
    oss << "  Dropped Frames: " << stats.droppedFrames << "\n";
    oss << "  Duplicated Frames: " << stats.duplicatedFrames << "\n";
    oss << "  Running: " << (running_ ? "Yes" : "No") << "\n";
    oss << "  Paused: " << (paused_ ? "Yes" : "No") << "\n";
    
    return oss.str();
}

void SynchronizerV2::dumpClockInfo() const {
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    Logger::instance().info("Clock Info Dump:");
    Logger::instance().info("  Audio - PTS: " + std::to_string(audioClock_.pts) + 
                           ", Speed: " + std::to_string(audioClock_.speed) + 
                           ", Paused: " + (audioClock_.paused ? "Yes" : "No"));
    Logger::instance().info("  Video - PTS: " + std::to_string(videoClock_.pts) + 
                           ", Speed: " + std::to_string(videoClock_.speed) + 
                           ", Paused: " + (videoClock_.paused ? "Yes" : "No"));
    Logger::instance().info("  External - PTS: " + std::to_string(externalClock_.pts) + 
                           ", Speed: " + std::to_string(externalClock_.speed) + 
                           ", Paused: " + (externalClock_.paused ? "Yes" : "No"));
}

// 私有方法实现

ErrorCode SynchronizerV2::updateClock(ClockType type, double pts, double time, int serial) {
    if (!initialized_) {
        return ErrorCode::NOT_INITIALIZED;
    }
    
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    ClockInfo* clock = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            clock = &audioClock_;
            break;
        case ClockType::VIDEO:
            clock = &videoClock_;
            break;
        case ClockType::EXTERNAL:
            clock = &externalClock_;
            break;
        default:
            return ErrorCode::INVALID_PARAMS;
    }
    
    if (time < 0) {
        time = getCurrentTime();
    }
    
    // 检查序列号
    if (serial != 0 && clock->serial != serial) {
        // 序列号不匹配，可能是seek操作，重置时钟
        resetClock(type);
        clock->serial = serial;
    }
    
    // 更新时钟
    clock->pts = pts;
    clock->time = time;
    clock->lastUpdate = std::chrono::steady_clock::now();
    
    // 平滑处理
    if (config_.smoothingWindow > 1) {
        clock->smoothedPts = smoothClock(type, pts);
    } else {
        clock->smoothedPts = pts;
    }
    
    // 更新历史记录
    updateClockHistory(type, pts);
    
    // 更新同步状态
    updateSyncState();
    
    // 定期更新统计信息
    auto now = std::chrono::steady_clock::now();
    if (std::chrono::duration_cast<std::chrono::milliseconds>(now - lastStatsUpdate_).count() > 100) {
        updateStats();
        lastStatsUpdate_ = now;
    }
    
    return ErrorCode::SUCCESS;
}

double SynchronizerV2::getClock(ClockType type, bool predict) const {
    std::lock_guard<std::mutex> lock(clockMutex_);
    
    const ClockInfo* clock = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            clock = &audioClock_;
            break;
        case ClockType::VIDEO:
            clock = &videoClock_;
            break;
        case ClockType::EXTERNAL:
            clock = &externalClock_;
            break;
        case ClockType::SYSTEM:
            return getCurrentTime();
        default:
            return 0.0;
    }
    
    if (clock->paused) {
        return clock->pts;
    }
    
    // 计算当前时间
    auto now = std::chrono::steady_clock::now();
    double elapsed = std::chrono::duration<double>(now - clock->lastUpdate).count();
    double currentPts = clock->pts + elapsed * clock->speed;
    
    // 如果启用预测
    if (predict && config_.enablePrediction) {
        return predictClock(type, config_.predictionWindow);
    }
    
    return currentPts;
}

void SynchronizerV2::resetClock(ClockType type) {
    ClockInfo* clock = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            clock = &audioClock_;
            break;
        case ClockType::VIDEO:
            clock = &videoClock_;
            break;
        case ClockType::EXTERNAL:
            clock = &externalClock_;
            break;
        default:
            return;
    }
    
    clock->pts = 0.0;
    clock->time = 0.0;
    clock->speed = 1.0;
    clock->serial = 0;
    clock->paused = false;
    clock->lastUpdate = std::chrono::steady_clock::now();
    clock->drift = 0.0;
    clock->smoothedPts = 0.0;
}

void SynchronizerV2::pauseClock(ClockType type, bool pause) {
    ClockInfo* clock = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            clock = &audioClock_;
            break;
        case ClockType::VIDEO:
            clock = &videoClock_;
            break;
        case ClockType::EXTERNAL:
            clock = &externalClock_;
            break;
        default:
            return;
    }
    
    if (clock->paused != pause) {
        if (pause) {
            // 暂停时保存当前PTS（直接计算，避免调用getClock导致死锁）
            if (!clock->paused) {
                auto now = std::chrono::steady_clock::now();
                double elapsed = std::chrono::duration<double>(now - clock->lastUpdate).count();
                clock->pts = clock->pts + elapsed * clock->speed;
            }
        }
        clock->paused = pause;
        clock->lastUpdate = std::chrono::steady_clock::now();
    }
}

void SynchronizerV2::selectMasterClock() {
    switch (config_.strategy) {
        case SyncStrategy::AUDIO_MASTER:
            masterClockType_ = ClockType::AUDIO;
            break;
        case SyncStrategy::VIDEO_MASTER:
            masterClockType_ = ClockType::VIDEO;
            break;
        case SyncStrategy::EXTERNAL_MASTER:
            masterClockType_ = ClockType::EXTERNAL;
            break;
        case SyncStrategy::ADAPTIVE:
            // 自适应选择逻辑
            if (config_.enableAdaptiveSync) {
                // 改进的自适应逻辑：优先选择音频，如果没有音频则选择视频
                // 注意：不依赖pts值，因为在播放开始时pts可能还是0
                if (hasAudioStream_) {
                    masterClockType_ = ClockType::AUDIO;
                } else if (hasVideoStream_) {
                    masterClockType_ = ClockType::VIDEO;
                } else {
                    masterClockType_ = ClockType::EXTERNAL;
                }
            } else {
                masterClockType_ = ClockType::AUDIO; // 默认音频
            }
            break;
    }

    Logger::instance().info("Master clock selected: "
                            + std::to_string(static_cast<int>(masterClockType_.load()))
                            + " (hasAudio=" + std::to_string(hasAudioStream_.load())
                            + ", hasVideo=" + std::to_string(hasVideoStream_.load()) + ")");
}

void SynchronizerV2::updateSyncState() {
    if (!running_) {
        state_ = SyncState::IDLE;
        return;
    }
    
    if (paused_) {
        return;
    }
    
    double syncError = calculateSyncErrorInternal();
    
    SyncState newState = state_;
    
    if (syncError <= config_.syncThreshold) {
        newState = SyncState::SYNCHRONIZED;
        recoveryAttempts_ = 0; // 重置恢复尝试次数
    } else if (syncError <= config_.adaptiveThreshold) {
        newState = SyncState::DRIFT;
    } else if (syncError <= config_.maxSyncError) {
        newState = SyncState::ERROR;
    } else {
        newState = SyncState::ERROR;
        // 尝试恢复
        if (recoveryAttempts_ < config_.maxRecoveryAttempts) {
            attemptRecovery();
            newState = SyncState::RECOVERING;
        }
    }
    
    if (newState != state_) {
        SyncState oldState = state_;
        state_ = newState;
        notifyStateChange(newState);
        
        Logger::instance().info("Sync state changed from " + std::to_string(static_cast<int>(oldState)) + 
                               " to " + std::to_string(static_cast<int>(newState)));
    }
}

void SynchronizerV2::updateStats() {
    // 统计信息在其他方法中已经更新
}

double SynchronizerV2::smoothClock(ClockType type, double newPts) {
    std::lock_guard<std::mutex> lock(historyMutex_);
    
    std::deque<double>* history = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            history = &audioClockHistory_;
            break;
        case ClockType::VIDEO:
            history = &videoClockHistory_;
            break;
        default:
            return newPts;
    }
    
    if (history->empty()) {
        return newPts;
    }
    
    // 简单的指数移动平均
    double lastSmoothed = history->back();
    return lastSmoothed * (1.0 - config_.smoothingFactor) + newPts * config_.smoothingFactor;
}

double SynchronizerV2::predictClock(ClockType type, double futureTime) const {
    // 注意：此方法假设调用者已经持有clockMutex_锁
    // 不能再调用getClock，否则会导致死锁
    
    const ClockInfo* clock = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            clock = &audioClock_;
            break;
        case ClockType::VIDEO:
            clock = &videoClock_;
            break;
        case ClockType::EXTERNAL:
            clock = &externalClock_;
            break;
        default:
            return 0.0;
    }
    
    if (clock->paused) {
        return clock->pts;
    }
    
    // 计算当前时间（不调用getClock避免死锁）
    auto now = std::chrono::steady_clock::now();
    double elapsed = std::chrono::duration<double>(now - clock->lastUpdate).count();
    double currentPts = clock->pts + elapsed * clock->speed;
    
    return currentPts + futureTime * clock->speed;
}

void SynchronizerV2::updateClockHistory(ClockType type, double pts) {
    std::lock_guard<std::mutex> lock(historyMutex_);
    
    std::deque<double>* history = nullptr;
    switch (type) {
        case ClockType::AUDIO:
            history = &audioClockHistory_;
            break;
        case ClockType::VIDEO:
            history = &videoClockHistory_;
            break;
        default:
            return;
    }
    
    history->push_back(pts);
    while (history->size() > static_cast<size_t>(config_.smoothingWindow)) {
        history->pop_front();
    }
}

void SynchronizerV2::attemptRecovery() {
    recoveryAttempts_++;
    lastRecoveryTime_ = std::chrono::steady_clock::now();
    
    Logger::instance().warning("Attempting sync recovery, attempt: " + std::to_string(recoveryAttempts_));
    
    // 重置时钟漂移
    std::lock_guard<std::mutex> lock(clockMutex_);
    audioClock_.drift = 0.0;
    videoClock_.drift = 0.0;
    externalClock_.drift = 0.0;
    
    // 可能需要重新选择主时钟
    if (config_.enableAdaptiveSync) {
        selectMasterClock();
    }
}

double SynchronizerV2::getCurrentTime() const {
    auto now = std::chrono::steady_clock::now();
    return std::chrono::duration<double>(now - startTime_).count();
}

double SynchronizerV2::getSystemTime() const {
    return av_gettime_relative() / 1000000.0;
}

void SynchronizerV2::notifyStateChange(SyncState newState) {
    if (syncEventCallback_) {
        syncEventCallback_(state_, newState);
    }
}

void SynchronizerV2::notifyFrameDrop(ClockType type, double pts) {
    if (frameDropCallback_) {
        frameDropCallback_(type, pts);
    }
}

void SynchronizerV2::notifyFrameDuplicate(ClockType type, double pts) {
    if (frameDuplicateCallback_) {
        frameDuplicateCallback_(type, pts);
    }
}

void SynchronizerV2::notifySyncError(double error, const std::string& reason) {
    if (syncErrorCallback_) {
        syncErrorCallback_(error, reason);
    }
}

} // namespace utils
} // namespace av