var gamejs = require('gamejs');
var $v = require('gamejs/utils/vectors');

function main() {
   gamejs.display.setCaption("Der Soldat");

   // create background
   var screen = gamejs.display.setMode([850, 500]);
   var displayRect = screen.rect;
   var bg = gamejs.image.load('images/ground.png');
   var clouds = gamejs.image.load('images/clouds.png');
   var heliGui = gamejs.image.load('images/heligui.png');

   // test
   var combatants = new gamejs.sprite.Group();
   var bombs = new gamejs.sprite.Group();

   var getCombatant = function(type) {
      var tank = new gamejs.scene.MovingSprite();
      var pos = [0,0];
      if (Math.random() > 0.5) {
         pos[0] = parseInt(Math.random() * displayRect.width);
      } else {
         pos[1] = parseInt(Math.random() * displayRect.height);
      }
      tank.setPosition(pos);
      tank.setImage('images/' + type + '.png');
      tank.setSpeed(type === 'tank' ? 5 : 2);
      tank.goTo([Math.random() * displayRect.width, Math.random() * displayRect.height]);
      return tank;
   }

   // sounds
   /*
   var pulse = new gamejs.mixer.Sound('sounds/lowpulse.ogg');
   var explosion = new gamejs.mixer.Sound('sounds/explosion.ogg');
   var kick =
   */

   var craters = [];

   /**
    * bomb
    */
   var Bomb = function(pos) {
      var EXP_SIZE = [60, 60];
      Bomb.superConstructor.apply(this, arguments);
      this.rect = new gamejs.Rect([0,0], EXP_SIZE);
      this.rect.center = pos;
      this.image = null;

      this.flightDuration = 0;
      this.explosionDuration = 0;
      this.isOnGround = false;

      this.frameTime = 0;
      this.currentFrame = 0;
      this.frameDuration = 80;
      this.frameDirection = 1;

      (new gamejs.mixer.Sound('sounds/kick.ogg')).play();
      (new gamejs.mixer.Sound('sounds/lowpulse.ogg')).play();
      return this;
   };
   gamejs.utils.objects.extend(Bomb, gamejs.sprite.Sprite)
   Bomb.prototype.draw = function(screen) {
      if (!this.image) return;
      screen.blit(this.image, this.rect);
      return;
   };
   Bomb.prototype.update = function(msDuration) {
      if (this.isOnGround) {
         this.frameTime += msDuration;

         if (!this.image || this.frameTime > this.frameDuration) {
            if (this.currentFrame < 0) {
               this.kill();
               return;
            }

            this.image = gamejs.image.load('images/explosion_' + this.currentFrame +'.png');
            this.frameTime = 0;
            if (this.currentFrame == 11) {
               var craterRect = new gamejs.Rect(this.rect);
               craterRect.width = 15
               craterRect.height = 15;
               craterRect.center = this.rect.center;
               craters.push({
                  image: gamejs.image.load('images/crater_' + parseInt(Math.random() * 6, 10) + '.png'),
                  rect: craterRect,
               });
               this.frameDirection = -1;
            }
            this.currentFrame += this.frameDirection;
         }
      } else {
         this.flightDuration += msDuration;
         if (this.flightDuration > 3500) {
            (new gamejs.mixer.Sound('sounds/explosion.ogg')).play();
            this.isOnGround = true;
         };
      }
      return;
   };

   /**
    * Main Game 'loop'
    *
    */
   var jitterPause = 300;
   var jitterCumulated = null;
   jitterPos = displayRect;

   var spawnPause = 3500;
   var spawnCumulated = null;

   var shootPause = 1500;
   var shootCumulated = shootPause * 2;


   function tick(msDuration) {
      // event handling
      gamejs.event.get().forEach(function(event) {

         if (event.type === gamejs.event.MOUSE_UP) {
            if (event.button === 0) {
               if (shootCumulated > shootPause) {
                  bombs.add(new Bomb(event.pos));
                  shootCumulated = 0;
               }
            }
         };
      });
      shootCumulated += msDuration;

      // update models
      combatants.update(msDuration);
      bombs.update(msDuration);

      // bomb combat collision detection
      bombs.sprites().filter(function(bomb) {
         if (bomb.currentFrame >= 8) {
            gamejs.sprite.spriteCollide(bomb, combatants, true);
         }
      }, this);

      // combatent spawn
      if (spawnCumulated === null || spawnCumulated > spawnPause) {
         if (Math.random() > 0.5) {
            combatants.add(getCombatant('tank'));
            combatants.add(getCombatant('tank'));
         } else {
            combatants.add(getCombatant('infantry'));
            combatants.add(getCombatant('infantry'));
         }
         spawnCumulated = 0;
      }
      spawnCumulated += msDuration;

      // draw
      screen.blit(bg, displayRect);
      craters.forEach(function(crater) {
         screen.blit(crater.image, crater.rect);
      });
      combatants.draw(screen);
      bombs.draw(screen);
      // screen jitter
      if (jitterCumulated === null | jitterCumulated >= jitterPause) {
         jitterPos = displayRect.move(-5 + (Math.random() * 5), -5 + (Math.random() * 5))
         jitterPos.width = displayRect.width * 1.3;
         jitterPos.height = displayRect.height * 1.3;
         jitterCumulated = 0;
      }
      jitterCumulated += msDuration;
      screen.blit(clouds, jitterPos);
      screen.blit(heliGui, displayRect);
   };
   gamejs.time.fpsCallback(tick, this, 30);
   return;
}

var PRELOAD_LIST = [
   'images/ground.png',
   'images/clouds.png',
   'images/heligui.png',

   'images/tank.png',
   'images/infantry.png',

   'sounds/kick.ogg',
   'sounds/explosion.ogg',
   'sounds/lowpulse.ogg',
];
for (var i=0;i<12;i++) {
   PRELOAD_LIST.push('images/explosion_' + i + '.png');
};
for (var i=0;i<6;i++) {
   PRELOAD_LIST.push('images/crater_' + i + '.png');
};
gamejs.preload(PRELOAD_LIST);
gamejs.ready(main);