let Game = {
  display: null,
  map: {},
  engine: null,
  player: null,
  pedro: null,
  ananas: null,

  init: function () {
    this.display = new ROT.Display({ spacing: 1.1 });
    document.body.appendChild(this.display.getContainer());

    this._generateMap();

    let scheduler = new ROT.Scheduler.Simple();
    scheduler.add(this.player, true);
    scheduler.add(this.pedro, true);

    this.engine = new ROT.Engine(scheduler);
    this.engine.start();
  },

  _generateMap: function () {
    let digger = new ROT.Map.Digger();
    let freeCells = [];

    let digCallback = function (x, y, value) {
      if (value) {
        return;
      }

      let key = x + "," + y;
      this.map[key] = ".";
      freeCells.push(key);
    };
    digger.create(digCallback.bind(this));

    this._generateBoxes(freeCells);
    this._drawWholeMap();

    this.player = this._createBeing(Player, freeCells);
    this.pedro = this._createBeing(Pedro, freeCells);
  },

  _createBeing: function (what, freeCells) {
    let index = Math.floor(ROT.RNG.getUniform() * freeCells.length);
    let key = freeCells.splice(index, 1)[0];
    let parts = key.split(",");
    let x = parseInt(parts[0]);
    let y = parseInt(parts[1]);
    return new what(x, y);
  },

  _generateBoxes: function (freeCells) {
    for (let i = 0; i < 10; i++) {
      let index = Math.floor(ROT.RNG.getUniform() * freeCells.length);
      let key = freeCells.splice(index, 1)[0];
      this.map[key] = "*";
      if (!i) {
        this.ananas = key;
      } /* first box contains an ananas */
    }
  },

  _drawWholeMap: function () {
    for (let key in this.map) {
      let parts = key.split(",");
      let x = parseInt(parts[0]);
      let y = parseInt(parts[1]);
      this.display.draw(x, y, this.map[key]);
    }
  },
};

let Player = function (x, y) {
  this._x = x;
  this._y = y;
  this._draw();
};

Player.prototype.getSpeed = function () {
  return 100;
};
Player.prototype.getX = function () {
  return this._x;
};
Player.prototype.getY = function () {
  return this._y;
};

Player.prototype.act = function () {
  Game.engine.lock();
  window.addEventListener("keydown", this);
};

Player.prototype.handleEvent = function (e) {
  let code = e.keyCode;
  if (code == 13 || code == 32) {
    this._checkBox();
    return;
  }

  let keyMap = {};
  keyMap[38] = 0;
  keyMap[33] = 1;
  keyMap[39] = 2;
  keyMap[34] = 3;
  keyMap[40] = 4;
  keyMap[35] = 5;
  keyMap[37] = 6;
  keyMap[36] = 7;

  /* one of numpad directions? */
  if (!(code in keyMap)) {
    return;
  }

  /* is there a free space? */
  let dir = ROT.DIRS[8][keyMap[code]];
  let newX = this._x + dir[0];
  let newY = this._y + dir[1];
  let newKey = newX + "," + newY;
  if (!(newKey in Game.map)) {
    return;
  }

  Game.display.draw(this._x, this._y, Game.map[this._x + "," + this._y]);
  this._x = newX;
  this._y = newY;
  this._draw();
  window.removeEventListener("keydown", this);
  Game.engine.unlock();
};

Player.prototype._draw = function () {
  Game.display.draw(this._x, this._y, "@", "#ff0");
};

Player.prototype._checkBox = function () {
  let key = this._x + "," + this._y;
  if (Game.map[key] != "*") {
    alert("There is no box here!");
  } else if (key == Game.ananas) {
    alert("Hooray! You found an ananas and won this game.");
    Game.engine.lock();
    window.removeEventListener("keydown", this);
  } else {
    alert("This box is empty :-(");
  }
};

let Pedro = function (x, y) {
  this._x = x;
  this._y = y;
  this._draw();
};

Pedro.prototype.getSpeed = function () {
  return 100;
};

Pedro.prototype.act = function () {
  let x = Game.player.getX();
  let y = Game.player.getY();

  let passableCallback = function (x, y) {
    return x + "," + y in Game.map;
  };
  let astar = new ROT.Path.AStar(x, y, passableCallback, { topology: 4 });

  let path = [];
  let pathCallback = function (x, y) {
    path.push([x, y]);
  };
  astar.compute(this._x, this._y, pathCallback);

  path.shift();
  if (path.length == 1) {
    Game.engine.lock();
    alert("Game over - you were captured by Pedro!");
  } else {
    x = path[0][0];
    y = path[0][1];
    Game.display.draw(this._x, this._y, Game.map[this._x + "," + this._y]);
    this._x = x;
    this._y = y;
    this._draw();
  }
};

Pedro.prototype._draw = function () {
  Game.display.draw(this._x, this._y, "P", "red");
};

Game.init();