text: const Engine = Matter.Engine;
  const World = Matter.World;
  const Bodies = Matter.Bodies;
  const Constraint = Matter.Constraint;
  var engine, world, backgroundImg, waterSound, backgroundMusic, cannonExplosion, pirateLaughSound;
  var canvas, angle, tower, ground, cannon, boat;
  var balls = [];
  var boats = [];
  
  var boatAnimation = [];
  var boatSpritedata, boatSpritesheet;
  
  var brokenBoatAnimation = [];
  var brokenBoatSpritedata, brokenBoatSpritesheet;
  var isGameOver = false; 
  var isLaughing = false;
  
  function preload() {
    backgroundImg = loadImage("./assets/background.gif");
    towerImage = loadImage("./assets/tower.png");
    boatSpritedata = loadJSON("assets/boat/boat.json");
    boatSpritesheet = loadImage("assets/boat/boat.png");
    brokenBoatSpritedata = loadJSON("assets/boat/broken_boat.json");
    brokenBoatSpritesheet = loadImage("assets/boat/broken_boat.png");
    pirateLaughSound = loadSound("./assets/pirate_laugh.mp3")
    backgroundMusic = loadSound("./assets/background_music.mp3")
    cannonExplosion = loadSound("./assets/cannon_explosion.mp3")
  }
  
  function setup() {
    canvas = createCanvas(1200,600);
    engine = Engine.create();
    world = engine.world;
    angle = -PI / 4;
    ground = new Ground(0, height - 1, width * 2, 1);
    tower = new Tower(150, 350, 160, 310);
    cannon = new Cannon(180, 110, 100, 50, angle);
  
    var boatFrames = boatSpritedata.frames;
    for (var i = 0; i < boatFrames.length; i++) {
      var pos = boatFrames[i].position;
      var img = boatSpritesheet.get(pos.x, pos.y, pos.w, pos.h);
      boatAnimation.push(img);
    }
  
    var brokenBoatFrames = brokenBoatSpritedata.frames;
    for (var i = 0; i < brokenBoatFrames.length; i++) {
      var pos = brokenBoatFrames[i].position;
      var img = brokenBoatSpritesheet.get(pos.x, pos.y, pos.w, pos.h);
      brokenBoatAnimation.push(img);
    }
  }
  
  function draw() {
    background(189);
    image(backgroundImg, 0, 0, width, height);
    if (!backgroundMusic.isPlaying()) { 
      backgroundMusic.play(); 
      backgroundMusic.setVolume(0.1); }
  
  
  
    Engine.update(engine);
    ground.display();
  
    showBoats();
  
   
    for (var i = 0; i < balls.length; i++) {
      showCannonBalls(balls[i], i);
      for (var j = 0; j < boats.length; j++) {
        if (balls[i] !== undefined && boats[j] !== undefined) {
          var collision = Matter.SAT.collides(balls[i].body, boats[j].body);
          if (collision.collided) {
            boats[j].remove(j);
  
            Matter.World.remove(world, balls[i].body);
            balls.splice(i, 1);
            i--;
            
          }
        } 
      }
    }
    cannon.display();
    tower.display();
  
  
  }
  
  
  //creating the cannon ball on key press
  function keyPressed() {
    if (keyCode === DOWN_ARROW) {
      var cannonBall = new CannonBall(cannon.x, cannon.y);
      cannonBall.trajectory = [];
      Matter.Body.setAngle(cannonBall.body, cannon.angle);
      balls.push(cannonBall);
    }
  }
  
  // function to show the ball.
  function showCannonBalls(ball, index) {
    ball.display();
    if (ball.body.position.x >= width || ball.body.position.y >= height - 50) {
      Matter.World.remove(world, ball.body);
      balls.splice(index, 1);
    }
  }
  
  
  //function to show the boat
  function showBoats() {
    if (boats.length > 0) {
      if (
        boats.length < 4 &&
        boats[boats.length - 1].body.position.x < width - 300
      ) {
        var positions = [-40, -60, -70, -20];
        var position = random(positions);
        var boat = new Boat(
          width,
          height - 100,
          170,
          170,
          position,
          boatAnimation
        );
  
  
        boats.push(boat);
      }
  
      for (var i = 0; i < boats.length; i++) {
        Matter.Body.setVelocity(boats[i].body, {
          x: -0.9,
          y: 0
          
        });
  
        boats[i].display();
        boats[i].animate();
       var collision = Matter.SAT.collides(tower.body, boats[i].body)
      if (collision.collided && ! boats[i].isBroken)
      if (collision.collided && !boats[i].isBroken) { //Added isLaughing flag and setting isLaughing to true 
      if(!isLaughing && !pirateLaughSound.isPlaying()){ 
        pirateLaughSound.play(); 
       isLaughing = true;
       isGameOver = true; 
       gameOver(); 
    }
  }   
  
      }
    } else {
      var boat = new Boat(width, height - 60, 170, 170, -60, boatAnimation);
      boats.push(boat);
    }
  }
  
  
  //releasing the cannonball on key release
  function keyReleased() {
    if (keyCode === DOWN_ARROW) {
      cannonExplosion.play();
      balls[balls.length - 1].shoot();
    }
  }
  function gameOver(){
    swal( { title: `Game Over!!!`, 
    text: "NICE TRY!!",
     imageUrl: "https://raw.githubusercontent.com/whitehatjr/PiratesInvasion/main/assets/boat.png", 
     imageSize: "150x150", confirmButtonText: "Play Again" 
    },
      function(isConfirm) { if (isConfirm) { location.reload(); } } )
  }
  
  