import 'package:star_lock/app_settings/app_settings.dart';
import '../../proto/talk_data_h264_frame.pb.dart';

class H264FrameHandler {
  final Map<int, TalkDataH264Frame> _frameBuffer = {};
  final void Function(List<int> frameData) onCompleteFrame;
  int _lastProcessedSeq = -1;

  H264FrameHandler({required this.onCompleteFrame});

  void handleFrame(TalkDataH264Frame frame) {
    // 存储帧
    _frameBuffer[frame.frameSeq] = frame;

    // 检查是否可以组装完整的 GOP (Group of Pictures)
    _tryAssembleFrames(frame.frameSeq);
  }

  void _tryAssembleFrames(int currentSeq) {
    // 找到连续的帧序列
    final List<int> sortedSeqs = _frameBuffer.keys.toList()..sort();
    final List<int> framesToProcess = [];

    // 从当前帧开始向前找到最近的 I 帧或 P 帧
    int? startFrameSeq;
    for (var seq in sortedSeqs.reversed) {
      final frame = _frameBuffer[seq];
      if (frame?.frameType == TalkDataH264Frame_FrameTypeE.I) {
        startFrameSeq = seq;
        break;
      } else if (frame?.frameType == TalkDataH264Frame_FrameTypeE.P) {
        // 检查 P 帧是否有对应的 I 帧
        if (_frameBuffer.containsKey(frame?.frameSeqI)) {
          startFrameSeq = seq;
          break;
        } else {
          // 丢弃没有对应 I 帧的 P 帧
          _frameBuffer.remove(seq);
        }
      }
    }

    if (startFrameSeq != null) {
      // 收集从 I 帧或 P 帧开始的连续帧
      int expectedSeq = startFrameSeq;
      for (var seq in sortedSeqs.where((s) => s >= startFrameSeq!)) {
        if (seq != expectedSeq) break;
        framesToProcess.add(seq);
        expectedSeq++;
      }

      if (framesToProcess.isNotEmpty) {
        _processFrames(framesToProcess);
      }
    } else {
      _clearOldFrames(currentSeq);
    }
  }

  void _clearOldFrames(int currentSeq) {
    // 清理比当前帧序列旧的帧
    _frameBuffer.removeWhere((seq, frame) => seq < currentSeq - 200); // 调整阈值
  }

  void _processFrames(List<int> frameSeqs) {
    // 按顺序组装帧数据
    final List<int> assembledData = [];

    for (var seq in frameSeqs) {
      final frame = _frameBuffer[seq]!;
      assembledData.addAll(frame.frameData);

      // 处理完后从缓冲区移除
      _frameBuffer.remove(seq);
    }

    // 回调完整的帧数据
    onCompleteFrame(assembledData);
  }

  void clear() {
    _frameBuffer.clear();
  }
}