Tower4

// Import graphics and ArrayList
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.util.ArrayList;
import java.util.Iterator;

/**
 * Subclass Tower4 inherits Tower data and methods
 * @author Elliott, Sina, and Christian 
 * @version June 16, 2014
 */
public class Tower4 extends Tower
{ 
	/**
	 * Construct Tower 4 object
	 * @param x the x coordinate of the Tower4
	 * @param y the y coordinate of the Tower4
	 * @param speed the speed of the Tower4 bullets
	 * @param firingRate the firing rate of the Tower4
	 */
	public Tower4(int x, int y, int speed, int firingRate)
	{
		super(x,y, firingRate, 250, 400,
				100, speed, 10, 20, 30, "tower4Drag");
		
		this.type=4;
		
	}
	/**
	 * Overrides the draw method for the Tower
	 */
	public void draw(Graphics g)
	{
	
		// Graphics for drawing sharper edges
		Graphics2D g2 = (Graphics2D) g;
		g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
				RenderingHints.VALUE_ANTIALIAS_ON);
		g2.setColor(Color.RED);
		
		
				// If the tower has an alien to fire at, calculate the amount to rotate the tower image below
				if (this.hasAlien)
				{
					if (this.closestAlien.onScreen()&&this.alienInRange(closestAlien)&&closestAlien.isAlive())
					{
				direction = Math.atan((closestAlien.xPos()-this.xPos)
						/ (this.yPos - closestAlien.yPos()));
				if (this.yPos<closestAlien.yPos())
				{
					direction += Math.PI;

				}
				else if (this.yPos == closestAlien.yPos())
				{
					if (this.xPos > closestAlien.xPos())
						direction = 3 * Math.PI / 2;
					else if (this.xPos < closestAlien.xPos())
						direction = Math.PI / 2;
				}
					}
				}
				
	
		// Rotates the graphics context by the direction then rotates back
		g2.rotate (direction, (int) xPos, (int) yPos);
		g.drawImage(towerImage,(int) (xPos-13), (int) (yPos - 13),
				null);
		// If it has an alien and a laser upgrade and the alien is valid then draw a laser connecting the tower to it
		if (this.hasAlien)
		{
			if (this.closestAlien.onScreen()&&this.alienInRange(closestAlien)&&closestAlien.isAlive()&&laserUpgrade)
			g2.fillRect((int) xPos, (int)(yPos-this.distanceClosestAlien()-9), 4, (int)this.distanceClosestAlien());
			
		}
		
		g2.rotate (-direction,(int) xPos, (int) yPos);
	}
	/**
	 * Calculates the distance to the closest alien squared
	 * @return the distance to the closest alien squared
	 */
	public double distanceClosestAlien()
	{
		
		return Math.sqrt((closestAlien.xPos() - this.xPos)*(closestAlien.xPos() - this.xPos)+(closestAlien.yPos() - this.yPos)*(closestAlien.yPos() - this.yPos));
	}
	
	
	/**
	 * Overrides the tower method to make a laser if the tower is upgraded
	 */
	public void alienSelect(ArrayList<Alien> aliens, ArrayList <Bullet> bullets)
	{
		// Increase the time of the tower by the time interval for the timerEventHandler
		this.time += 35;

		// Iterator to go through all the aliens
		Iterator<Alien> it = aliens.iterator();
		// If the tower doesn't have an alien to fire at, try to find one
		if (!this.hasAlien)
		{

			int index = 0;
			int indexOfClosestAlien = -1;
			// Goes through the aliens until there is one that is alive, on screen and in range
			while (!(this.hasAlien) && it.hasNext())
			{

				Alien nextAlien = it.next();
				if (this.alienInRange(nextAlien) && nextAlien.isAlive()&&nextAlien.onScreen())
				{
					indexOfClosestAlien = index;
					this.hasAlien = true;
				}
				index++;
			}
			// If no alien meets the condition, the tower doesn't have an alien to fire at

			if (indexOfClosestAlien == -1)
				this.hasAlien = false;
			// Otherwise, keep going until the closest alien is found
			else
			{
				// Initially the closest alien is the alien that was in range, alive and on screen from the previous loop
				closestAlien = aliens.get(indexOfClosestAlien);
				// Go through the remaining aliens and if the distance from the alien to the tower is less than the closest alien
				// it becomes the new closest alien

				while (it.hasNext())
				{
					Alien nextAlien = it.next();
					if ((nextAlien.xPos() - this.xPos)
							* (nextAlien.xPos() - this.xPos)
							+ (nextAlien.yPos() - this.yPos)
							* (nextAlien.yPos() - this.yPos) < (closestAlien
							.xPos() - this.xPos)
							* (closestAlien.xPos() - this.xPos)
							+ (closestAlien.yPos() - this.yPos)
							* (closestAlien.yPos() - this.yPos)
							&& nextAlien.isAlive()&&nextAlien.onScreen())
						closestAlien = nextAlien;
				}
				this.time=0;
				
				
			}
		}
		// If the tower already has an alien to fire at
		if (this.hasAlien)
		{
			// If the closest alien is in range, alive an don screen then attack it
			if (this.alienInRange(closestAlien) && closestAlien.isAlive()&&closestAlien.onScreen())
			{
				// If it doesn't have a laser upgrade, fire a regular bullet
				if (this.time % firingRate == 0&&!laserUpgrade)
				{
					bullets.add(new Bullet(this.xPos, this.yPos, this.sizeOfBullets,
							this.speed, this.damage, this.closestAlien,this));
					
				}
				// Otherwise just take damage since the laser inflicts constant damage
				else if (laserUpgrade)
					closestAlien.takeDamage(this.damage);
			}
			else
				// Otherwise set the tower to find a new alien to fire at the next time the method is called
			this.hasAlien = false;
		}
		
		

	}
	/**
	 * Overrides Tower method since Tower4 doesn't have explode upgrade
	 */
	public boolean isExploding()
	{
		return false;
	}
	/**
	 * Overrides Tower method since Tower4 doesn't have freeze upgrade
	 */
	public boolean isFreezing()
	{
		return false;
	}
	
}