// Description: Maze Program
// Author: Chris Wilcox
// Date: 2/1/2013

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.Image;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Scanner;

import javax.swing.Box;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.border.Border;
import javax.swing.border.LineBorder;

public class Maze extends JFrame { 

	// Window information
	private int windowWidth;
	private int windowHeight;

	// Maze variables
	private char mazeData[][];
	private int mazeRows;
	private int mazeCols;
	private int finalRow;
	private int finalCol;
	private int currRow;
	private int currCol;
	private int prevRow = -1;
	private int prevCol = -1;

	// User interface
	private JPanel panel;
	private Image nemo, dory, both, shark, jelly;
	private ArrayList<JButton> buttons;

	// Robot constructor
	public Maze(String fileName) {

		// Read maze
		readMaze(fileName);

		// Graphics setup
		setupGraphics();
	}    

	// Get width
	public int getRows()
	{
		return mazeRows;
	}
	
	// Get height
	public int getCols()
	{
		return mazeCols;
	}

	// Move right
	public boolean moveRight()
	{
		// Legal move?
		if ((currCol+1) < mazeCols)
			if ((mazeData[currRow][currCol+1] == 'W') || // Water
				(mazeData[currRow][currCol+1] == 'N'))   // Nemo
			{
				currCol++;
				redraw(true);
				return true;
			}
		System.out.println("currentCol:" + currCol);
		return false;
	}

	// Move left
	public boolean moveLeft()
	{
		// Legal move?
		if (currCol > 0)
			if ((mazeData[currRow][currCol-1] == 'W') || // Water
				(mazeData[currRow][currCol-1] == 'N'))   // Nemo
			{
				currCol--;
				redraw(true);
				return true;
			}
		System.out.println("currentCol:" + currCol);
		return false;
	}

	// Move up
	public boolean moveUp()
	{
		// Legal move?
		if (currRow > 0)
			if ((mazeData[currRow-1][currCol] == 'W') || // Water
				(mazeData[currRow-1][currCol] == 'N'))   // Nemo
			{
				currRow--;
				redraw(true);
				return true;
			}
		System.out.println("currentRow:" + currRow);
		return false;
	}

	// Move down
	public boolean moveDown()
	{
		// Legal move?
		if ((currRow+1) < mazeRows)
			if ((mazeData[currRow+1][currCol] == 'W') || // Water
				(mazeData[currRow+1][currCol] == 'N'))   // Nemo
			{
				currRow++;
				redraw(true);
				return true;
			}
		System.out.println("currentRow:" + currRow);
		return false;
	}

	private void redraw(boolean print)
	{
		// Wait for awhile
		try {
			Thread.sleep(500);
		} catch(InterruptedException ex) {
			Thread.currentThread().interrupt();
		}
		// if (print)
		//	System.out.println("Moving to row " + currRow + ", column " + currCol);

		// Update position
		if ((prevRow >= 0) && (prevCol >= 0))
			mazeData[prevRow][prevCol] = 'W';
		mazeData[currRow][currCol] = 'D';
		
		// Compute index and remove icon
		int index = (prevRow * mazeCols) + prevCol;
		if ((prevRow >= 0) && (prevCol >= 0))
			buttons.get(index).setIcon(null);

		// Compute index and add icon
		index = (currRow * mazeCols) + currCol;
		if ((currRow == finalRow) && (currCol == finalCol))
			buttons.get(index).setIcon(new ImageIcon(both));
		else
			buttons.get(index).setIcon(new ImageIcon(dory));

		// Maze solved
		if ((currRow == finalRow) && (currCol == finalCol))
			{System.out.println("currentRow when found Nemo:" + currRow);
		    System.out.println("currentCol when found Nemo:" + currCol);
			System.out.println("Dory found Nemo!");}

		// Store previous location
		prevRow = currRow;
		prevCol = currCol;
	}

	// Set button
	private void setButton(JButton button, int row, int col) {

		if (mazeData[row][col] == 'D') {
			button.setIcon(new ImageIcon(dory));
			currRow = row;
			currCol = col;
		}
		else if (mazeData[row][col] == 'N') {
			button.setIcon(new ImageIcon(nemo));
			finalRow = row;
			finalCol = col;
		}
		else if (mazeData[row][col] == 'S')
			button.setIcon(new ImageIcon(shark));
		else if (mazeData[row][col] == 'J')
			button.setIcon(new ImageIcon(jelly));
	}


	// Read maze
	private void readMaze(String filename)
	{
		try {

			// Open file
			Scanner scan = new Scanner(new File(filename));

			// Read numbers
			mazeRows = scan.nextInt();
			mazeCols = scan.nextInt();

			// Allocate maze
			mazeData = new char[mazeRows][mazeCols];

			// Read maze
			for (int row = 0; row < mazeRows; row++)
			{
				// Read line
				String line = scan.next();

				for (int col = 0; col < mazeCols; col++)
				{
					mazeData[row][col] = line.charAt(col);
				}
			}

			// Close file
			scan.close();

		} catch (IOException e) {
			System.out.println("Cannot read maze: " + filename);
			System.exit(0);
		}
	}

	// Setup graphics
	private void setupGraphics()
	{

		// Create grid
		panel = new JPanel();
		panel.setLayout(new GridLayout(mazeRows, mazeCols, 0, 0));
		add(Box.createRigidArea(new Dimension(0, 5)), BorderLayout.NORTH);    
		add(panel, BorderLayout.CENTER);

		// Look and feel
		try {
			UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		// Configure window
		windowWidth = mazeCols  * 100;
		windowHeight = mazeRows * 100;
		setSize(windowWidth, windowHeight);
		setTitle("Maze");
		setResizable(false);
		setLocationRelativeTo(null);
		setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
		setAlwaysOnTop(true);

		// Load and scale images
		ImageIcon icon0 = new ImageIcon("Nemo.jpg");
		Image image0 = icon0.getImage();
		nemo = image0.getScaledInstance(100, 100, Image.SCALE_DEFAULT);

		ImageIcon icon1 = new ImageIcon("Dory.jpg");
		Image image1 = icon1.getImage();
		dory = image1.getScaledInstance(100, 100, Image.SCALE_DEFAULT);

		ImageIcon icon2 = new ImageIcon("Both.jpg");
		Image image2 = icon2.getImage();
		both = image2.getScaledInstance(100, 100, Image.SCALE_DEFAULT);

		ImageIcon icon3 = new ImageIcon("Shark.jpg");
		Image image3 = icon3.getImage();
		shark = image3.getScaledInstance(100, 100, Image.SCALE_DEFAULT);

		ImageIcon icon4 = new ImageIcon("Jelly.jpg");
		Image image4 = icon4.getImage();
		jelly = image4.getScaledInstance(100, 100, Image.SCALE_DEFAULT);

		// Build panel of buttons
		buttons = new ArrayList<JButton>(); 
		for (int row = 0; row < mazeRows; row++) {
			for (int col = 0; col < mazeCols; col++) {

				// Initialize and add button
				JButton button = new JButton();
				Border border = new LineBorder(Color.darkGray, 4);
				button.setOpaque(true);
				button.setBackground(Color.blue); 
				button.setBorder(border);
				setButton(button, row, col);
				panel.add(button);
				buttons.add(button);
			}
		}

		// Show window
		redraw(false);
		setVisible(true);
	}
}