import 'package:fis_measure/interfaces/enums/annotation.dart';
import 'package:fis_measure/interfaces/enums/operate.dart';
import 'package:fis_measure/interfaces/process/items/item.dart';
import 'package:fis_measure/interfaces/process/workspace/application.dart';
import 'package:fis_measure/interfaces/process/workspace/recorder.dart';
import 'package:get/get.dart';

class MeasureRecorder implements IMeasureRecorder {
  int _lastId = 0;
  final List<_RecordModelBase> _records = [];
  late final IApplication _application;

  MeasureRecorder(IApplication application) {
    _application = application;
  }

  /// 获取一个新的记录Id
  @override
  int newRecordId() {
    return _lastId + 1;
  }

  /// 添加测量项记录
  ///
  /// [name] 测量项名称
  @override
  void recordMeasureItem(String name) {
    _records.add(_MeasureModel(name));
    _increaseId();
  }

  /// 添加注释记录
  ///
  /// [type] 注释类型
  @override
  void recordAnnotation(AnnotationType type) {
    _records.add(_AnnotationModel(type));
    // _increaseId();// 注释不占Id
  }

  /// 撤销一次操作
  bool undoOnce() {
    if (_records.isEmpty) {
      return false;
    }
    _finishLast();
    _cleanMeasureList();
    final result = _undoOnce();
    _checkReactive();
    if (result == null) return false;
    if (result.recordType == MeasureRecordType.measure) {
      _decreaseId();
    }
    return true;
  }

  /// 清除所有记录
  void clear() {
    if (_records.isEmpty) return;

    _finishLast();
    _cleanMeasureList();

    final len = _records.length;
    for (var i = 0; i < len; i++) {
      _undoOnce();
    }
    _checkReactive();
    _resetId();
  }

  _RecordModelBase? _undoOnce() {
    final record = _records.last;
    bool removed = false;
    if (record.recordType == MeasureRecordType.measure) {
      removed = _undoOnceMeasure(record as _MeasureModel);
    } else if (record.recordType == MeasureRecordType.annotation) {
      removed = _undoOnceAnnotation(record as _AnnotationModel);
    }
    if (removed) {
      _records.removeLast();
      _checkResetId();
      return record;
    } else {
      return null;
    }
  }

  void _finishLast() {
    if (_application.currentOperateType == MeasureOperateType.measure) {
      _application.activeMeasureItem?.finishOnce();
    } else {
      _application.activeAnnotationItem?.finishLast();
    }
  }

  bool _undoOnceMeasure(_MeasureModel record) {
    final index = _application.measureItems
        .lastIndexWhere((e) => e.meta.name == record.name);
    if (index < 0) return false;

    final item = _application.measureItems[index];
    if (item is ITopMeasureItem) {
      _application.measureItems.remove(item);
    } else {
      if (item.feature != null) {
        item.cancelOnce();
      } else if (item.measuredFeatures.isNotEmpty) {
        item.measuredFeatures.removeLast();
      }
      if (item.measuredFeatures.isEmpty) {
        _application.measureItems.removeAt(index);
      }
    }
    return true;
  }

  void _checkReactive() {
    if (_application.measureItems.isEmpty) {
      if (_application.activeMeasureItem != null) {
        if (_application.currentOperateType == MeasureOperateType.measure) {
          _application.switchItem(_application.activeMeasureItem!.meta);
        }
      }
    }
  }

  void _cleanMeasureList() {
    int len = _application.measureItems.length;
    final needRemoveIdxArr = <int>[];
    for (int i = 0; i < len; i++) {
      final item = _application.measureItems[i];
      if (item.feature == null && item.measuredFeatures.isEmpty) {
        needRemoveIdxArr.add(i);
      }
    }
    if (needRemoveIdxArr.isNotEmpty) {
      final arr = needRemoveIdxArr.reversed;
      for (var i in arr) {
        _application.measureItems.removeAt(i);
      }
    }
  }

  bool _undoOnceAnnotation(_AnnotationModel record) {
    final matchs =
        _application.annotationItems.where((e) => e.type == record.type);
    if (matchs.isEmpty) return false;

    final item = matchs.last;
    item.features.removeLast();
    return true;
  }

  void _resetId() {
    _lastId = 0;
  }

  void _increaseId() {
    _lastId++;
  }

  void _decreaseId() {
    _lastId--;
    if (_lastId < 0) _lastId = 0;
  }

  void _checkResetId() {
    if (_application.measureItems.isEmpty) {
      _resetId();
    } else {
      final isFeatureEmpty = _application.measureItems
          .every((e) => e.measuredFeatures.isEmpty && e.feature == null);
      if (isFeatureEmpty) {
        _resetId();
      }
    }
  }
}

class _MeasureModel extends _RecordModelBase {
  _MeasureModel(this.name) : super(MeasureRecordType.measure);

  String name;
}

class _AnnotationModel extends _RecordModelBase {
  _AnnotationModel(this.type) : super(MeasureRecordType.annotation);

  AnnotationType type;
}

class _RecordModelBase {
  _RecordModelBase(this.recordType);
  MeasureRecordType recordType;
}

enum MeasureRecordType {
  measure,
  annotation,
}