var inherits = require('inherits');
var Game = require('crtrdg-gameloop');
var Entity = require('crtrdg-entity');
var Keyboard = require('crtrdg-keyboard');

inherits(Player, Entity);

function Player(options){
  this.position = { 
    x: options.position.x, 
    y: options.position.y 
  };

  this.size = {
    x: options.size.x,
    y: options.size.y
  };

  this.velocity = {
    x: options.velocity.x,
    y: options.velocity.y
  };
  
  this.speed = options.speed;
  this.friction = options.friction;
  this.color = options.color;
}

Player.prototype.move = function(velocity){
  this.position.x += velocity.x;
  this.position.y += velocity.y;
};

Player.prototype.checkBoundaries = function(){
  if (this.position.x <= 0){
    this.position.x = 0;
  }

  if (this.position.x >= this.game.width - this.size.x){
    this.position.x = this.game.width - this.size.x;
  }

  if (this.position.y <= 0){
    this.position.y = 0;
  }

  if (this.position.y >= this.game.height - this.size.y){
    this.position.y = this.game.height - this.size.y;
  }
};

Player.prototype.keyboardInput = function(){
  if ('A' in keyboard.keysDown){
    this.velocity.x = -this.speed;
  }

  if ('D' in keyboard.keysDown){
    this.velocity.x = this.speed;
  }

  if ('W' in keyboard.keysDown){
    this.velocity.y = -this.speed;
  }

  if ('S' in keyboard.keysDown){
    this.velocity.y = this.speed;
  }
};

var game = new Game({
  canvasId: 'game',
  width: window.innerWidth,
  height: window.innerHeight,
  backgroundColor: '#E187B8'
});

var keyboard = new Keyboard(game);

var player = new Player({
  position: { x: 10, y: 10 },
  size: { x: 10, y: 10 },
  velocity: { x: 0, y: 0 },
  speed: 3,
  friction: 0.9,
  color: '#fff'
});

player.addTo(game);

player.on('update', function(interval){
  this.keyboardInput(keyboard);

  this.move(this.velocity);
  this.velocity.x *= this.friction;
  this.velocity.y *= this.friction;

  this.checkBoundaries();
});

player.on('draw', function(draw){
  draw.fillStyle = this.color;
  draw.fillRect(this.position.x, this.position.y, this.size.x, this.size.y);
});