fis_lib_measure/lib/view/player/control_board/location_info.dart

part of 'control_board.dart';

/// 播放帧位置信息（帧索引、时间索引）
class LocationInfo extends StatelessWidget {
  LocationInfo({Key? key}) : super(key: key);

  /// 值展示固定宽度
  // ignore: constant_identifier_names
  static const double C_VALUE_DISPLAY_WIDTH = 30.0;

  final playerController = Get.find<IPlayerController>() as VidPlayerController;

  late final int totalFrameCount;
  late final double totalDuration;

  @override
  Widget build(BuildContext context) {
    _initTotalInfo();
    return Row(
      mainAxisSize: MainAxisSize.min,
      children: [
        _buildLabelColumn(),
        SizedBox(
          width: C_VALUE_DISPLAY_WIDTH,
          child: _CurrentValueDisplayColumn(
            totalDuration: totalDuration,
            totalFrameCount: totalFrameCount,
          ),
        ),
        _buildTotalDescColumn(),
      ],
    );
  }

  void _initTotalInfo() {
    final channel = playerController.dataChannel;
    totalFrameCount = channel.imageCount;
    totalDuration = totalFrameCount / channel.probe.frameRate;
  }

  Widget _buildLabelColumn() {
    return _SpanColumn(
      alignment: CrossAxisAlignment.start,
      durationSpan: i18nBook.measure.playLocationDurationLabel.t,
      frameCountSpan: i18nBook.measure.playLocationFrameCountLabel.t,
    );
  }

  Widget _buildTotalDescColumn() {
    final totalDurationStr = '/${totalDuration.toStringAsFixed(1)} s';
    final totalFrameCountStr = '/$totalFrameCount';
    return _SpanColumn(
      durationSpan: totalDurationStr,
      frameCountSpan: totalFrameCountStr,
    );
  }
}

class _CurrentValueDisplayColumn extends StatefulWidget {
  const _CurrentValueDisplayColumn({
    Key? key,
    required this.totalDuration,
    required this.totalFrameCount,
  }) : super(key: key);

  final double totalDuration;
  final int totalFrameCount;

  @override
  State<StatefulWidget> createState() => _CurrentValueDisplayColumnState();
}

class _CurrentValueDisplayColumnState
    extends State<_CurrentValueDisplayColumn> {
  final playerController = Get.find<IPlayerController>() as VidPlayerController;

  int currentIndex = 0;

  @override
  void initState() {
    playerController.frameUpdated.addListener(_onFrameUpdated);
    super.initState();
  }

  @override
  void dispose() {
    playerController.frameUpdated.addListener(_onFrameUpdated);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final currFrameNum = currentIndex + 1;

    double currDuration;
    if (currFrameNum == widget.totalFrameCount) {
      currDuration = widget.totalDuration;
    } else {
      currDuration =
          (currentIndex / widget.totalFrameCount) * widget.totalDuration;
    }

    return _SpanColumn(
      alignment: CrossAxisAlignment.end,
      frameCountSpan: currFrameNum.toString(),
      durationSpan: currDuration.toStringAsFixed(1),
    );
  }

  void _onFrameUpdated(Object sender, VidUsImage frame) {
    if (frame.index == currentIndex) return;

    if (mounted) {
      setState(() {
        currentIndex = frame.index;
      });
    }
  }
}

class _SpanColumn extends StatelessWidget {
  const _SpanColumn({
    Key? key,
    this.alignment = CrossAxisAlignment.start,
    this.durationSpan = '',
    this.frameCountSpan = '',
  }) : super(key: key);

  final CrossAxisAlignment alignment;
  final String durationSpan;
  final String frameCountSpan;

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      crossAxisAlignment: alignment,
      children: [
        _buildLine(durationSpan),
        _buildLine(frameCountSpan),
      ],
    );
  }

  Widget _buildLine(String content) {
    return Text(
      content,
      style: const TextStyle(color: Colors.white),
    );
  }
}