vacuum-cleaner-v2.dart

/*
 * Ali Ghanbari - 970216657
 * online compiler: https://dartpad.dev/a69b65959d0207f02adf4e78c532f87a?null_safety=true
 */

///
/// Constants
///
enum Action { Left, Right, Suck, Idle }
enum RoomState { Clean, Dirty }

const left = 0, right = 1;

///
/// State
///

class Environment {
  final int location; // 0 for left, 1 for right
  final Map<int, RoomState> rooms;

  Environment({required this.location, required this.rooms}); // constructor

  RoomState get currentRoom => rooms[location]!;

  // check if all rooms are clean
  bool get clean => rooms.entries.every((e) => e.value == RoomState.Clean);

  @override
  String toString() {
    return '${roomName(location)}\t${rooms[left]}\t${rooms[right]}\t';
  }
}

///
/// Agent
///

Action reflexVacuumAgent(Environment env) {
  if (env.currentRoom == RoomState.Dirty) {
    return Action.Suck;
  } else if (env.location == left) {
    return Action.Right;
  } else if (env.location == right) {
    return Action.Left;
  } else {
    return Action.Idle;
  }
}

int simulate(Environment environment) {
  int score = 0;
  while (!environment.clean) {
    var action = reflexVacuumAgent(environment);
    environment = applyAction(environment, action);
    score = updateScore(score, action);
  }
  return score;
}

Environment applyAction(Environment env, Action action) {
  if (action == Action.Suck) {
    return Environment(
      location: env.location,
      rooms: Map.from(env.rooms)..[env.location] = RoomState.Clean,
    );
  } else if (action == Action.Left) {
    return Environment(location: left, rooms: env.rooms);
  } else if (action == Action.Right) {
    return Environment(location: right, rooms: env.rooms);
  } else {
    return env;
  }
}

int updateScore(int score, Action action) {
  if (action == Action.Suck) {
    return score + 1;
  } else {
    return score - 1;
  }
}

///
/// Main Program
///

void main() {
  var allStates = List.generate(
    8, // 8 possible states
    (i) => Environment(
      location: (i ~/ 4) % 2,
      rooms: {
        left: roomState((i ~/ 2) % 2 == 0),
        right: roomState(i % 2 == 0),
      },
    ),
  );

  print('Loc\tLeft Room\tRight Room\tScore');
  print(allStates.map((env) => '$env${simulate(env)}').join('\n'));
  print('Average Score: ${allStates.map(simulate).reduce(sum) / 8}');
}

///
/// Utility
///
RoomState roomState(bool isClean) {
  return isClean ? RoomState.Clean : RoomState.Dirty;
}

String roomName(int location) {
  if (location == left) {
    return 'Left';
  } else {
    return 'Right';
  }
}

int Function(int a, int b) sum = (a, b) => a + b;

/* Output
Loc     Left Room       Right Room      Score
Left    RoomState.Clean RoomState.Clean 0
Left    RoomState.Clean RoomState.Dirty 0
Left    RoomState.Dirty RoomState.Clean 1
Left    RoomState.Dirty RoomState.Dirty 1
Right   RoomState.Clean RoomState.Clean 0
Right   RoomState.Clean RoomState.Dirty 1
Right   RoomState.Dirty RoomState.Clean 0
Right   RoomState.Dirty RoomState.Dirty 1
Average Score: 0.5
*/