import java.awt.*;
import java.util.*;
import java.util.concurrent.TimeUnit;

import javax.swing.JOptionPane;

public class Memory extends java.applet.Applet
{
	private int xMouse;
	private int yMouse;
	private boolean mouseClicked = false;
	private boolean firstRun = true;
	private boolean gameOver = false;
	private static final int WIDTH = 100;
	private static int numClick = 0;
	private long startTime;
	private long elapsedTime = -1;
	
	/*****  add the rest of your instance variables here  *****/


	/*Sets the background of your memory board to black*/
	public void init() 
	{
		setSize(400,400);
		setBackground(Color.BLACK);  	
	} 	

	/*This is main in java applets
	You don't need to change this method, but you need to fill the methods called
	inside the paint method, i.e., buildBoard and displayHit
	 */
	public void paint(Graphics canvas)
	{
		displayBoard(canvas);
		
		if(firstRun) //for the first run we need to build our random board
		{
			buildBoard(4);
			firstRun = false;
		} 
		else if(!gameOver) // once our board is built we will display the game
		{
			if (mouseClicked) // if the mouse has been clicked
			{
				displayHit(canvas); //find which box the user clicked
				mouseClicked = false;
				numClick++;
				if(numClick == 1) startTime = System.nanoTime();  // count elapsed time
			}
		}
		
	}

	/*
   	DO NOT change this method
   	determines if the mouse has been pressed
   	sets x and y Mouse to the location of the mouse arrow
   	redraws the image
	 */
	public boolean mouseDown(Event e, int x, int y ) 
	{
		mouseClicked = true; 
		xMouse = x;
		yMouse = y;
		repaint();
		return true;
	}

	/*DO NOT change this method
   	redraws the scene
	 */
	public void update ( Graphics canvas ) 
	{
		paint(canvas);
		
		if(gameOver = isGameOver())
		{
			if(elapsedTime < 0)
				elapsedTime = TimeUnit.SECONDS.convert(System.nanoTime()-startTime, TimeUnit.NANOSECONDS);
			JOptionPane.showMessageDialog(null, "Game Over! \nYou found all pairs in " + elapsedTime + " seconds!");
		}
	}

	/*DO NOT change this method
   	draw the board
	 */
	public void displayBoard(Graphics canvas)
	{
		canvas.setColor(Color.WHITE);

		for(int i = 0; i < 400; i += WIDTH)
			for(int j = 0; j < 400; j += WIDTH)
				canvas.drawRect(i, j, WIDTH, WIDTH);

	}

	/***** fill this method *****/
	/*
   	pre: pass in the size of the board
   	post: build an array that holds the memory values for a board of size * size
   	the board will hold two of each int from 0 to size*size/2-1 randomly placed in the array
	 */
	public void buildBoard(int size)
	{ 
	
	}


	/***** fill this method *****/
	/*
	Pre: xMouse and yMouse have been initialized (stored in the associated instance variables)
	Post: A circle is displayed in the correct box on the screen
	*/
	public void displayHit(Graphics canvas)
	{
		int i, j;
		// add your code to implement the game functionality
		// when you locate the clicked region, call displayCircle method below to draw the circle
		
	}

	/***** fill this method *****/
	/*
	Pre: i and j are the indices of the clicked region, value is the integer
	     at (i, j) on the board
	Post: A circle is displayed in the correct box on the screen
	      finish the part to set the color of canvas according to value
	 */
	private void displayCircle(Graphics canvas, int i, int j, int value)
	{
		// use canvas.setColor(...) to set the color of the circle
		
		canvas.fillOval(j*100+30, i*100+30, 40, 40);
	}
	
	/***** fill this method *****/
	/*
	Pre: none
	Post: return true if the game is over
	 */
	private boolean isGameOver()
	{
		
		return false;
	}

}