gobang/lib/state/State.dart

import 'package:gobang/state/UserContext.dart';

abstract class State {
  int _step = 0;

  int get step => _step;
  int _reg = 0;

  int get reg => _reg;
  UserContext _userContext;

  State(UserContext userContext) : _userContext = userContext;

  // 悔棋只能悔棋三次
  bool regretChess();

  // 认输10步之内不能认输
  bool surrender();

  play() {
    _step++;
  }
}

/// [StartState] 开始状态
class StartState extends State {
  StartState(UserContext userContext) : super(userContext);

  // 悔棋只能悔棋三次
  @override
  bool regretChess() {
    return false;
  }

  @override
  bool surrender() {
    return false;
  }

  @override
  play() {
    super.play();
    if (_step >= 4) {
      _userContext.setState(MidState(_userContext)
        .._step = _step
        .._reg = _reg);
    }
  }
}

/// [MidState] 中场状态
class MidState extends State {
  MidState(UserContext userContext) : super(userContext);

  @override
  int get _reg {
    return super._reg;
  }

  // 悔棋只能悔棋三次
  @override
  bool regretChess() {
    _reg++;
    if (_reg == 3) {
      print('切换到白热化阶段');
      _userContext.setState(EndState(_userContext)
        .._step = _step
        .._reg = _reg);
    }
    return true;
  }

  @override
  bool surrender() {
    return true;
  }
}

/// [EndState] 结尾状态
class EndState extends State {
  EndState(UserContext userContext) : super(userContext);

  // 悔棋只能悔棋三次
  @override
  regretChess() {
    return false;
  }

  @override
  surrender() {
    return true;
  }
}