PImage b;

Object world[][] = new Object[30][30];


class Wall{
  
}
Wall wall = new Wall();

class  Empty{
  
}
Empty empty = new Empty();;



Player p;
HashSet monsters = new HashSet();
HashSet bullets = new HashSet();
void setup(){
  size(480,480);
  
  for(int x = 0; x < 30; x++){
    for(int y = 0; y < 30; y++){
      world[x][y] = empty;
    }    
  }
  p = new Player();
  loadguys();
  for(int i = 0; i < 20; i++){
     monsters.add(new Monster());
  }
}

void draw(){
  frameRate(60);
    background(0);
    noStroke();

    Iterator i = bullets.iterator();
    while(i.hasNext()){
       Bullet b = (Bullet) i.next(); 
       
       if(b.hit()){
          i.remove(); 
       }
       b.move();
       b.draw();
    }


    if(frameCount % 10 == 0){
      p.move();
    }
      p.draw();
      i = monsters.iterator();
      while(i.hasNext()){
         Monster m = (Monster) i.next();
         
          m.wait--;
          if(m.wait <= 0){
             m.wait = monsters.size(); 
             m.move();
          }

         m.draw(); 
      }
      
}



HashMap guyart = new HashMap();
void loadguys(){
  loadguy("L");
  loadguy("R");
  loadguy("U");
  loadguy("D");
}


class Bullet{
    int x,y;
    String dir;
    Bullet(int px,int py,String pdir){
      x = px; y = py;
      dir = pdir;

  }
  
    void draw(){
        stroke(255); strokeWeight(1);
       if(dir.equals("U") || dir.equals("D")){
          line(16*x +4,16*y,16*x +4,16*(y+1));
          line(16*x +5,16*y,16*x +5,16*(y+1));
       } else {
          line(16*x ,16*y+4,16*(x+1) ,16*y+4);
          line(16*x ,16*y+5,16*(x+1) ,16*y+5);
       } 
    }
  
    void  move(){
        moveTo(newXFromDir(x,y,dir),newYFromDir(x,y,dir)); 
    }

    void moveTo(int newx, int newy){
     
      x = newx; y = newy;

    }
    boolean hit(){
       Object what = whatsInWorld(x,y);
       if(what == wall){
          return true;
       }
       if(what instanceof Monster){

          monsters.remove(what);
          world[x][y] = empty;
          return true;
       }
      return false; 
    }
  
}

class Guy{
  int x, y;
   String dir = "R";
   String  frame;
   String type;
   
   void randomizeDir(){
          int r = int(random(4));
      switch(r){
         case 0: dir = "R"; break; 
         case 3: dir = "L"; break; 
         case 2: dir = "D"; break; 
         case 1: dir = "U"; break; 
      } 
   }
   
   Guy(){
      if(random(1)< .5){
         frame = "1"; 
      } else {
         frame = "2"; 
      }
      randomizeDir();
            x = int(random(0,30));
            y = int(random(0,30));
            
            while(!(empty.equals(world[x][y]))){     
              print("got "+world[x][y]);
              x = int(random(0,30));
              y = int(random(0,30));
            }

            
   } 
   color c ;
  void draw(){
   fill(c);noStroke();
    drawguy(x,y,dir,frame);
  }
  
  void advanceFrame(){
     if("1".equals(frame)){
       frame = "2"; 
        return;
       }
     if("2".equals(frame)) {
      frame = "1";
      return;
     }
  }
   void animate(){ 
         int newX = newXFromDir(x,y,dir);
         int newY = newYFromDir(x,y,dir);
        if(empty.equals(whatsInWorld(newX,newY))){
           world[x][y] = empty;
           x = newX; y = newY;
           world[x][y] = this;

        }
}
  
}

int newXFromDir(int x, int y, String dir){
    if("L".equals(dir)){
       return x-1; 
    }
    if("R".equals(dir)){
       return x+1; 
    }
    return x;
}
int newYFromDir(int x, int y, String dir){
    if("U".equals(dir)){
       return y-1; 
    }
    if("D".equals(dir)){
       return y+1; 
    }
    return y;
}



Object  whatsInWorld(int x,int y){
  if(x < 0 || x >= 30 || y < 0 || y >= 30){
     return wall; 
  }
  return world[x][y];
}

class Monster extends Guy{
  String type;  
  int wait;
  Monster(){
       super();
       wait = monsters.size();
       int r = int(random(3));
       if(r == 0) { type="R"; c = color(255,0,0); }
       if(r == 1) {type="G";c = color(0,255,0); }
       if(r == 2) {type="B";c = color(0,0,255); }
                   world[x][y] = type;
    }
    
    void move(){
       if(random(10) < 3){
          randomizeDir();
       } 
       advanceFrame();
      animate();
    }
    
}


class Player extends Guy{
  Player(){
    super();
    type = "P";
    c = color(150)  ;
                world[x][y] = "P";
  }
  
  
  
  void move(){
    boolean ismoving = false;

    if(isKeyDown(32)){
      Bullet b   = new Bullet (newXFromDir(x,y,dir),newYFromDir(x,y,dir),dir);
      bullets.add(b);
//        println("bang"); 
          
  }

    if(isKeyDown(37)){
      dir="L";
      ismoving = true;
    }
    if(isKeyDown(38)){
      dir="U";
            ismoving = true;
    }
    if(isKeyDown(39)){
      dir="R";
            ismoving = true;
    }
    if(isKeyDown(40)){
      dir="D";
            ismoving = true;
    }
    if(ismoving){
      advanceFrame();
      animate();
    }
    
  }    
}


void loadguy(String dir){
  loadguy_helper(dir,"1");
  loadguy_helper(dir,"2");
}

void loadguy_helper(String dir, String frame){
  PImage i = loadImage("red_"+dir+"_"+frame+".png");
  guyart.put(dir+frame,i);

}


void drawguy(int x, int y, String dir, String frame){
 rect(16*x,16*y,16,16);  
 
  image((PImage)guyart.get(dir+frame),16*x,16*y);
}


HashSet keysDown = new HashSet();
void keyPressed(){
//  println(this.keyEvent.getKeyCode());
  this.keysDown.add(this.keyEvent.getKeyCode());
}
void keyReleased(){
  this.keysDown.remove(this.keyEvent.getKeyCode());  
}
boolean isKeyDown(int keyCode){
  if(keysDown.contains(keyCode)) return true;
  return false; 
}