vacuum-cleaner.dart

/*
 * Ali Ghanbari - 970216657
 * online compiler: https://dartpad.dev/a72a868f4690256e2f58f69b01823942?null_safety=true
 */

///
/// Constants
///
enum Action { Left, Right, Suck }
enum RoomState { Clean, Dirty }
const leftRoom = 0, rightRoom = 1;

///
/// State
///

class State {
  final int location; // 0 for left, 1 for right
  final Map<int, RoomState> rooms; //room location to clean

  State(this.location, this.rooms); // constructor

  @override
  String toString() => '(${roomName(location)}, $rooms)';
}

///
/// Agent
///

class Vacuum {
  State state; // enviroment
  int _actions = 0; // number of actions

  Vacuum(this.state); // constructor

  int clean() {
    while (!everyRoomClean) {
      if (currentRoomIsDirty) {
        doAction(Action.Suck);
      } else {
        if (state.location == leftRoom) {
          doAction(Action.Right);
        } else {
          doAction(Action.Left);
        }
      }
    }
    return 3 - _actions;
  }

  void doAction(Action action) {
    if (action == Action.Suck) {
      state = State(
        state.location,
        Map<int, RoomState>.from(state.rooms)
          ..[state.location] = RoomState.Clean,
      );
    } else if (action == Action.Left) {
      state = State(leftRoom, state.rooms);
    } else if (action == Action.Right) {
      state = State(rightRoom, state.rooms);
    }
    _actions++;
  }

  bool get currentRoomIsDirty {
    return state.rooms[state.location] == RoomState.Dirty;
  }

  bool get everyRoomClean {
    return state.rooms.values.every((room) => room == RoomState.Clean);
  }
}

///
/// Main Program
///

void main() {
  var allPossibleStates = List.generate(
    8, // 8 possible states
    (i) => State((i ~/ 4) % 2, {
      leftRoom: roomState((i ~/ 2) % 2 == 0),
      rightRoom: roomState(i % 2 == 0),
    }),
  );

  //print('All Possible States:');
  //print(allPossibleStates);

  var allStateScores = allPossibleStates.map((state) => {
        'state': state.toString(),
        'score': Vacuum(state).clean(),
      });

  print('\nAll State Scores:');
  print(allStateScores.map((e) => e.toString()).join('\n'));

  var averageScore = allStateScores
          .map<int>((e) => e['score'] as int)
          .reduce((value, sum) => sum + value) /
      8;

  print('\nAverage Score:');
  print(averageScore);
}

///
/// Utility
///
RoomState roomState(bool isClean) =>
    isClean ? RoomState.Clean : RoomState.Dirty;

String roomName(int location) => {
      leftRoom: 'left',
      rightRoom: 'right',
    }[location]!;