// Swarm.java
// Written by THC for CS 5 Lab Assignment #2.
// Modified by Scot Drysdale to demostrate iterators.
// Maintains information about a swarm of bugs.

import java.awt.*;
import java.util.ArrayList;
import java.util.Iterator;

public class Swarm {
  private ArrayList<Bug> insects;    // array of Bug objects
  
  // Constructor.  Given how many Bug objects we'll ever have at once, create
  // the array and initialize bugCount to 0.
  // Note that this version ignores howMany.
  public Swarm(int howMany) {
    insects = new ArrayList<Bug>();
  }
  
  // Return how many Bugs currently exist.
  public int getBugCount() {
    return insects.size();
  }
  
  // Draw every Bug that currently exists.
  // This version uses the foreach construct.
  public void draw(Graphics page) {
    for (Bug aBug: insects)
      aBug.draw(page);
  }
  
  // Move every Bug that currently exists.
  // Any Bug that moves fully off the top of the window no longer exists.
  // Because we remove bugs, we have to use an iterator rather than a for-all
  public void move() {
    
  	Iterator<Bug> iter = insects.iterator();
    while (iter.hasNext()) {
      // Move a Bug.  If it's still in the window, go on to the next one.
      // Otherwise, terminate this Bug.
    	Bug thisBug = iter.next();
      if (!thisBug.move())
        iter.remove();   // moved fully off the top
    }
  }
  
  
  // Add a new Bug to the Swarm, but only if there's room.
  public void add(Point where) {
  	insects.add(new Bug(where));
  }
  
  // Hit all bugs that fall under a given Point.
  // All bugs whose bounding box contains the Point are terminated.
  public void hitBugs(Point where) { 
    Iterator<Bug> iter = insects.iterator();
    while (iter.hasNext()) {
      if (iter.next().isHit(where))  // Was current bug hit?
        iter.remove();               // If so, remove it.
    }
  }
}