/**
 * The main program class that makes the window and handles menu events.
 *
 * Please see Readme.txt for more information.
 *
 * Assignment: MP2
 * Class: CS 340, Fall 2005
 * TA: Nitin Jindal
 * System: jEdit, jdk-1.5.0.4, Windows XP
 * @author Michael Leonhard (CS account mleonhar)
 * @version 22 Sep 2005
*/

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Random;

public class MemoryGame implements ActionListener
{
	// data fields
	private JFrame mainFrame;					// top level window
	private Container mainContentPane;			// frame that holds card field and turn counter
	private TurnCounterLabel turnCounterLabel;
	private ImageIcon cardIcon[]; // 0-7 are faces, 8 is back
	
	/**
	 * Make a JMenuItem, associate an action command and listener, add to menu
	*/
	private static void newMenuItem(String text, JMenu menu, ActionListener listener)
	{
		JMenuItem newItem = new JMenuItem(text);
		newItem.setActionCommand(text);
		newItem.addActionListener(listener);
		menu.add(newItem);
	}
	
	/**
	 * Loads the card icons from GIF files
	 *
	 * @return ImageIcon[9] containing the card icons
	*/
	private ImageIcon[] loadCardIcons()
	{
		// allocate array to store icons
		ImageIcon icon[] = new ImageIcon[9];
		// for each icon
		for(int i = 0; i < 9; i++ )
		{
			// make a new icon from a cardX.gif file
			String fileName = "card" + i + ".gif";
			icon[i] = new ImageIcon(fileName);
			// unable to load icon
			if(icon[i].getImageLoadStatus() == MediaTracker.ERRORED)
			{
				// inform the user of the error and then quit
				JOptionPane.showMessageDialog(this.mainFrame
					, "The image " + fileName + " could not be loaded."
					, "Memory Game Error", JOptionPane.ERROR_MESSAGE);
				System.exit(1);
			}
		}
		return icon;
	}
	
	/**
	 * Default constructor loads card images, makes window
	*/
	public MemoryGame()
	{
		// make toplevel window
		this.mainFrame = new JFrame("Memory (CS340 MP2 Michael Leonhard)");
		this.mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.mainFrame.setSize(400,500);
		this.mainContentPane = this.mainFrame.getContentPane();
		this.mainContentPane.setLayout(new BoxLayout(this.mainContentPane, BoxLayout.PAGE_AXIS)); 
		// make counter label
		this.turnCounterLabel = new TurnCounterLabel();
		// Menu bar
		JMenuBar menuBar = new JMenuBar();
		this.mainFrame.setJMenuBar(menuBar);
		// Game menu
		JMenu gameMenu = new JMenu("Game");
		menuBar.add(gameMenu);
		newMenuItem("New Game", gameMenu, this);
		newMenuItem("Exit", gameMenu, this);
		// Help menu
		JMenu helpMenu = new JMenu("Help");
		menuBar.add(helpMenu);
		newMenuItem("How To Play", helpMenu, this);
		newMenuItem("About", helpMenu, this);
		// Load icons
		this.cardIcon = loadCardIcons(); 
	}
	
	/**
	 * Shows an instructional dialog box to the user
	*/
	private void showInstructions()
	{
		dprintln("MemoryGame.showInstructions()");
		final String HOWTOPLAYTEXT = 
			"How To Play\r\n" +
			"\r\n" +
			"The game consists of 8 pairs of cards.  At the start of the game,\r\n"+
			"every card is face down.  The object is to find all the pairs and\r\n"+
			"turn them face up.\r\n"+
			"\r\n"+
			"Click on two cards to turn them face up. If the cards are the \r\n"+
			"same, then you have discovered a pair.  The pair will remain\r\n"+
			"turned up.  If the cards are different, they will flip back\r\n"+
			"over automatically after a short delay.  Continue flipping\r\n"+
			"cards until you have discovered all of the pairs.  The game\r\n"+
			"is won when all cards are face up.\r\n"+
			"\r\n"+
			"Each time you flip two cards up, the turn counter will\r\n"+
			"increase.  Try to win the game in the fewest number of turns!";
		JOptionPane.showMessageDialog(this.mainFrame, HOWTOPLAYTEXT
			, "How To Play", JOptionPane.PLAIN_MESSAGE);
	}
	
	/**
	 * Shows an dialog box with information about the program
	*/
	private void showAbout()
	{
		dprintln("MemoryGame.showAbout()");
		final String ABOUTTEXT = 
			"Memory Game is a Java program\r\n" +
			"written by Michael Leonhard.\r\n" +
			"\r\n" +
 			"Michael is an undergraduate studying\r\n" +
			"Computer Science at the University\r\n" +
			"of Illinois at Chicago.  This program\r\n" +
			"is a project for CS340 Software Design.\r\n" +
			"\r\n" +
			"Michael has a website at:\r\n" +
			"http://tamale.net/\r\n" +
			"------------------------------------------\r\n" +
 			"CS 340, Fall 2005\r\n" +
 			"Instructor: Pat Troy\r\n" +
 			"TA: Nitin Jindal\r\n" +
 			"Assignment 2 (MP2)\r\n" +
			"Created 21 Sep 2005 with\r\n" +
			"jdk-1.5.0.4 and jEdit on Windows XP";
		JOptionPane.showMessageDialog(this.mainFrame, ABOUTTEXT
			, "About Memory Game", JOptionPane.PLAIN_MESSAGE);
	}
	
	/**
	 * Handles menu events.  Necessary for implementing ActionListener.
	 *
	 * @param e object with information about the event
	*/
	public void actionPerformed(ActionEvent e)
	{
		dprintln("actionPerformed " + e.getActionCommand());
		if(e.getActionCommand().equals("New Game")) newGame();
		else if(e.getActionCommand().equals("How To Play")) showInstructions();
		else if(e.getActionCommand().equals("About")) showAbout();
		else if(e.getActionCommand().equals("Exit")) System.exit(0);
	}
	
	/**
	 * Prints debugging messages to the console
	 *
	 * @param message the string to print to the console
	 */
	static public void dprintln( String message )
	{
		//System.out.println( message );
	}
	
	/**
	 * Randomize the order of elements in an int array
	 *
	 * The method iterates over the array.  For each position in the array,
	 * another position is chosen randomly and the two integer values are
	 * exchanged.
	 *
	 * @param a the int[] to randomize
	*/
	public static void randomizeIntArray(int[] a)
	{
		Random randomizer = new Random();
		// iterate over the array
		for(int i = 0; i < a.length; i++ )
		{
			// choose a random int to swap with
			int d = randomizer.nextInt(a.length);
			// swap the entries
			int t = a[d];
			a[d] = a[i];
			a[i] = t;
		}
	}
	
	/**
	 * Makes a new set of cards and puts them in a new card field (a JPanel)
	 *
	 * @return new panel populated with new cards
	*/
	public JPanel makeCards()
	{
		// make the panel to hold all of the cards
		JPanel panel = new JPanel(new GridLayout(4, 4));
		// this set of cards must have their own manager
		TurnedCardManager turnedManager = new TurnedCardManager(this.turnCounterLabel);
		// all cards have same back
		ImageIcon backIcon = this.cardIcon[8];
		
		// make an array of card numbers: 0, 0, 1, 1, 2, 2, ..., 7, 7
		int cardsToAdd[] = new int[16];
		for(int i = 0; i < 8; i++)
		{
			cardsToAdd[2*i] = i;
			cardsToAdd[2*i + 1] = i;
		}
		// randomize the order of the array
		randomizeIntArray(cardsToAdd);
		
		// make each card object
		for(int i = 0; i < cardsToAdd.length; i++)
		{
			// number of the card, 0-7, randomized
			int num = cardsToAdd[i];
			// make the card object
			Card newCard = new Card(turnedManager, this.cardIcon[num], backIcon, num);
			// add it to the panel
			panel.add(newCard);
		}
		// return the filled panel
		return panel;
	}
	
	/**
	 * Prepares a new game (first game or non-first game)
	*/
	public void newGame()
	{
		// reset the turn counter to zero
		this.turnCounterLabel.reset();
		// clear out the content pane (removes turn counter label and card field)
		this.mainContentPane.removeAll();
		// make a new card field with cards, and add it to the window
		this.mainContentPane.add(makeCards());
		// add the turn counter label back in again
		this.mainContentPane.add(this.turnCounterLabel);
		// show the window (in case this is the first game)
		this.mainFrame.setVisible(true);
	}
}