var canvas;
var ctx;
var width = 600;
var height = 600;
var starfield;
var starX = 0;
var starY = 0;
var starY2 = -600;


var score = 0;
var highscore = 10;
var alive = true;
var lives = 3;
var gameStarted = false;

livesimage = new Image()
livesimage.src = 'hart.png';

var levens3 = true;
var levens2 = false;
var levens1 = false;


function livedraw()
{
	if(lives == 3)
	{
		ctx.drawImage(livesimage,10,10,50,38);
		ctx.drawImage(livesimage,50,10,50,38);
		ctx.drawImage(livesimage,90,10,50,38);
	}
	if(lives == 2)
	{
		ctx.drawImage(livesimage,10,10,50,38);
		ctx.drawImage(livesimage,50,10,50,38);
	}
	if(lives == 1)
	{
		ctx.drawImage(livesimage,10,10,50,38);
	}

}


function clearCanvas() {
  ctx.clearRect(0, 0, width, height);
}

function init() {
  canvas = document.getElementById('canvas');
  ctx = canvas.getContext('2d');
  ship = new Image();
  ship.src = 'ship.png';
  starfield = new Image();
  starfield.src = 'starfield.jpg';
  document.addEventListener('keydown', keyDown, false);
  document.addEventListener('keyup', keyUp, false);
  canvas.addEventListener('click', gameStart, false);
  gameLoop();
}


function gameStart() {
  gameStarted = true;
  canvas.removeEventListener('click', gameStart, false);
}


function gameLoop() {
  clearCanvas();
  drawStarfield();
  if (alive && gameStarted && lives > 0) {


    hitTest();
    moveEnemies();
    moveLaser();
    drawEnemies();
    drawShip();
    drawLaser();
    shipCollision();
	livedraw();
	update();
	DeleteItems();
	console.log(highscore);

  }
  scoreTotal();

  setTimeout(gameLoop, 1000 / 30);
}


function scoreTotal() {
  ctx.font = 'bold 18px VT323';
  ctx.fillStyle = '#fff';
  ctx.fillText('Score: ', 10, 55);
  ctx.fillText(score, 70, 55);
  ctx.fillText('Lives: ', 10, 30);
  ctx.fillText(lives, 68, 30);

  if (!alive) {
    ctx.fillText('Game Over!', 245, (height / 2));


    ctx.fillRect((width / 2) - 65, (height / 2) + 10, 100, 40);
    ctx.fillStyle = '#000';
    ctx.fillText('Opnieuw?', 252, (height / 2) + 35);
    canvas.addEventListener('click', continueButton, false);
  }


  if (!gameStarted) {
    ctx.font = 'bold 50px VT323';
    ctx.fillText('Sander Gouman top down', (width / 2) - 210, (height / 2));
    ctx.font = 'bold 20px VT323';
    ctx.fillText('Klik om te spelen', (width / 2) - 56, (height / 2) + 30);
    ctx.fillText('Beweeg met de pijltjes', (width / 2) - 100, (height / 2) + 60);
    ctx.fillText('Gebruik de spatiebalk om te schieten', (width / 2) - 100, (height / 2) + 90);
  }
}


function continueButton(e) {
  var cursorPos = getCursorPos(e);
  if (cursorPos.x > (width / 2) - 53 && cursorPos.x < (width / 2) + 47 && cursorPos.y > (height / 2) + 10 && cursorPos.y < (height / 2) + 50) {
    alive = true;
    lives = 3;
    reset();
    canvas.removeEventListener('click', continueButton, false);
  }
}


function getCursorPos(e) {
  var x;
  var y;

  if (e.pageX || e.pageY) {
    x = e.pageX;
    y = e.pageY;
  } else {
    x = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
    y = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;
  }

  x -= canvas.offsetLeft;
  y -= canvas.offsetTop;
  var cursorPos = new cursorPosition(x, y);

  return cursorPos;
}

function cursorPosition(x, y) {
  this.x = x;
  this.y = y;
}

function checkLives() {
  lives -= 1;
  if (lives > 0) {
    reset();
  } else if (lives == 0) {


    alive = false;
	if (score > parseInt(localStorage.getItem("highscore"))) {
            localStorage.setItem("highscore", score);

        }


  }
}


function reset() {
  var enemy_reset_x = 50;
  ship_x = (width / 2) - 25;
  ship_y = height - 75;
  ship_w = 50;
  ship_h = 57;

  for (var i = 0; i < enemies.length; i++) {
    enemies[i][0] = enemy_reset_x;
    enemies[i][1] = -45;
    enemy_reset_x = enemy_reset_x + enemy_w + 60;
  }
}


function drawStarfield() {
  ctx.drawImage(starfield, starX, starY);
  ctx.drawImage(starfield, starX, starY2);

  if (starY > 600) {
    starY = -599;
  }

  if (starY2 > 600) {
    starY2 = -599;
  }

  starY += 1;
  starY2 += 1;
}

window.onload = init;