/* Chompers eat hearts, and are destroyed by bombs. */




class Chomper implements Entity
{
  static final float killRadiusBase = 5, killRadiusPerSize = 6.25, smellRadiusBase = 5, smellRadiusPerSize = 2.5;

  final static int defaultInitialSize = 4;
  int size, prevSize;
  final static int smallestSize = 2;

  final static int growAnimationLength = 75, growAnimationHalfPeriod = 5;
  int growAnimationT = -growAnimationLength;

  int walkAnimationBaseT = 0;

  float y;
  int minX, maxX;
  
  float x;
  boolean flipped;
  boolean dead;
  
  Chomper(int minX, int maxX, float y, int size)
  {
    this.minX = minX;
    this.maxX = maxX;
    this.y = y;
    this.size = size;
    this.dead = false;
  }

  Chomper(int minX, int maxX, float y)
  {
    this(minX, maxX, y, defaultInitialSize);
  }
  
  void doPhysics0()
  {
    float bestDistSq = 0;
    int besthi = -1, bestti = -1;
    for (int hi = 0; hi < theHearts.size(); ++hi) {
      Heart h = (Heart)theHearts.get(hi);
      for (int ti = 0; ti < Heart.trailLength; ti++) {
        boolean nearEnd = false;
        for (int ri = -1; ri <= 1; ri++) {
          if (!h.trailOn[(ti+ri+Heart.trailLength)%Heart.trailLength] && ti == (t/Heart.framesPerTrailPoint + ri + Heart.trailLength) % Heart.trailLength) {
            nearEnd = true;
          }
        }
        //if (nearEnd)
        //  continue;
        float dsq = distsq(h.trailX[ti],h.trailY[ti],x,y);
        if (besthi == -1 || dsq < bestDistSq) {
          bestDistSq = dsq;
          besthi = hi;
          bestti = ti;
        }
      }
    }
    //if (besthi != -1)
      //println("besthi = " + besthi + " dsq = " + bestDistSq);
    float smellRadius = size * smellRadiusPerSize + smellRadiusBase;
    if (besthi != -1 && bestDistSq < sq(smellRadius)) {
      Heart h = (Heart)theHearts.get(besthi);
      float dx = h.trailX[(bestti+1)%Heart.trailLength]-h.trailX[bestti];
      float dy = h.trailY[(bestti+1)%Heart.trailLength]-h.trailY[bestti];
      /*if (bestDistSq > sq(size * smellRadius * .5)) {
        dx = h.trailX[(bestti+1)%Heart.trailLength]-x;
        dy = h.trailY[(bestti+1)%Heart.trailLength]-y;
      }*/
      if (dx < 0 && !flipped)
        flipped = true;
      float ilen = 1.0/sqrt(dx*dx+dy*dy);
      x += 3*dx*ilen;
      y += 3*dy*ilen;
    }
    
    
    int tt = t % ((maxX - minX) * 2);
    flipped = tt >= maxX - minX;
    x = flipped ? 2 * maxX - minX - tt : minX + tt;

    // Detect hearts and bombs.
    
    for (int i = 0; i < theHearts.size(); ++ i)
    {
      Heart h = (Heart)theHearts.get(i);
      if (!h.dead && dist(h.x, h.y, x, y) < size * killRadiusPerSize + killRadiusBase)
      {
        playSound(monsterhit);
        h.die();
	startGrowAnimation(size);
	++ size;
      }
    }

    for (int i = 0; i < theBombs.size(); ++ i)
    {
      Bomb h = (Bomb)theBombs.get(i);
      if (dist(h.x, h.y, x, y) < size * killRadiusPerSize + killRadiusBase)
      {
        h.explode();
	if (size == smallestSize)
	  die();
	else
	{
	  startGrowAnimation(size);
	  size = max(size / 2, smallestSize);
	}
      }
    }
  }

  void startGrowAnimation(int prevSize)
  {
    this.prevSize = prevSize;
    growAnimationT = t;
    walkAnimationBaseT = t + growAnimationLength;
  }

  void die()
  {
    theEntities.remove(this);
    dead = true;
  }
  
  void doPhysics1() { 
  }
  
  void draw()
  {
    int drawSize, walkAnimationT;
    if (t <= growAnimationT + growAnimationLength)
    { drawSize = ((t - growAnimationT) / growAnimationHalfPeriod) % 2 == 1 ? size : prevSize;
      walkAnimationT = 0;
    } else
    { drawSize = size;
      walkAnimationT = t - walkAnimationBaseT;
    }
    walkAnimationT = t;
    chomperAnimation.display(x - chomperAnimation.w * drawSize / 2, y - chomperAnimation.h * drawSize / 2, walkAnimationT, true, drawSize, flipped);
  }

  void addToLevel()
  {
    theEntities.add(this);
  }

  void levelStart()
  {
    minX += leftBorder;
    maxX += leftBorder;
  }
}