MysteryGame - Refactored

main.dart

import 'dart:io';

abstract class GameState {
  String getPrompt();
  void process(String input, MysteryGame game);
}

//#region Concrete states
class TheKitchenGameState extends GameState {

  static const List<String> KITCHEN_ACTION_LIST = [
    'chop',
    'chop',
    'chop',
    'chop',
    'chop',
    'fry',
    'serve',
  ];

  int completedKitchenActionIndex = 0;

  @override
  String getPrompt() {
    if (completedKitchenActionIndex == 0) {
      return 'Welcome to The Kitchen. Do your actions without mistake!';
    }
  }

  @override
  void process(String input, MysteryGame game) {
    if (input == KITCHEN_ACTION_LIST[completedKitchenActionIndex]) {
      completedKitchenActionIndex++;
      if (completedKitchenActionIndex == KITCHEN_ACTION_LIST.length) {
        game.state = SuccessGameState();
      }
    } else {
      game.state = DeadGameState();
    }
  }
}

class StartGameState extends GameState {
  @override
  String getPrompt() {
    return 'Type ready to start the game';
  }

  @override
  void process(String input, MysteryGame game) {
    if (input == 'ready') {
      game.state = TheKitchenGameState();
    }
  }

}

class SuccessGameState extends GameState {
  @override
  String getPrompt() {
    return 'Congratulations! You are successful 🎉';
  }

  @override
  void process(String input, MysteryGame game) {
    if (input == 'RIP') {
      game.state = DeadGameState();
    }
  }
}


class DeadGameState extends GameState {
  @override
  String getPrompt() {
    return 'You are dead. Like this game? Feel free to retry.';
  }

  @override
  void process(String input, MysteryGame game) {
    if (input == 'retry') {
      game.state = StartGameState();
    }
  }

}

//#endregion

class MysteryGame {
  GameState state;

  MysteryGame() {
    state = StartGameState();
  }

  String getPrompt() {
    return state.getPrompt();
  }

  void process(String input) {
    return state.process(input, this);
  }
}


void main() {
  print('MysteryMaze v1.0');
  print('---');
  MysteryGame game = MysteryGame();
  while (true) {
    if (game.getPrompt() != null) {
      print(game.getPrompt());
    }
    String input = stdin.readLineSync();
    if (input == 'exit') {
      break;
    } else {
      game.process(input);
    }
  }
  print('Good bye! Come MysteryMaze again soon!');
}