//
//  SudokuApplet.java
//  SudokuApplet
//
//  Created by Jack Wimberley on 4/6/08.
//  Copyright (c) 2008 __MyCompanyName__. All rights reserved.
//
//  A simple signed Java applet
//	This implementation of Algorithm X owes a lot to Stan Chesnutt's code.
//	I learned a lot about how to do this by looking over his freely provided code,
//	basing my code on his (restricting it for only Sudoku puzzles).
//	Many thanks to Mr. Chesnutt.

import java.awt.*;
import java.util.*;
import java.io.*;
import java.applet.*;
import javax.swing.*;
import java.awt.event.*;

class NoSolutionException extends Exception {}
class NoUniqueSolutionException extends Exception{}

public class SudokuApplet extends JApplet implements ActionListener{
	public Container content;
	public JPanel panel;
	public JPanel[][] grid;
	public JTextField[][] info;
	public JButton solve;
	public JButton clear;
	public JButton reset;
	public JLabel dialog;

	public AlgorithmPOE poe;
	public AlgorithmDLX dlx;
	public int[][] data;
	public int[][] solution;
	
	public void init() {
		content = getContentPane();
		panel = new JPanel();
		panel.setLayout(new GridBagLayout());
		GridBagConstraints c = new GridBagConstraints();
		
		// LOOK AND FEEL
		try {
			UIManager.setLookAndFeel(
				UIManager.getSystemLookAndFeelClassName());
		} catch(Exception e){}
		
		// PUZZLE
		grid = new JPanel[3][3];
		info = new JTextField[9][9];
		for (int i = 0; i < 3; i++) {
			for (int j = 0; j < 3; j++) {
				grid[i][j] = new JPanel();
				grid[i][j].setLayout(new GridBagLayout());
				for (int x = 0; x < 3; x++) {
					for (int y = 0; y < 3; y++) {
						int row = 3*j+y;
						int col = 3*i+x;
						info[row][col] = new JTextField(2);
						info[i][j].setEditable(true);
						c.gridx = x;
						c.gridy = y;
						c.ipadx = 0;
						c.ipady = 0;
						grid[i][j].add(info[row][col],c);
					}
				}
				c.gridx = i;
				c.gridy = j;
				c.ipadx = 8;
				c.ipady = 8;
				panel.add(grid[i][j],c);
			}
		}
		
		// Solve Button
		c.gridx = 0;
		c.gridy = 3;
		c.gridwidth = 1;
		solve = new JButton("Solve");
		panel.add(solve, c);
        solve.addActionListener(this);
		
		// Reset Button
		c.gridx = 1;
		c.gridy = 3;
		c.gridwidth = 1;
		reset = new JButton("Reset");
		panel.add(reset, c);
        reset.addActionListener(this);
		
		// Clear Button
		c.gridx = 2;
		c.gridy = 3;
		c.gridwidth = 1;
		clear = new JButton("Clear");
		panel.add(clear, c);
        clear.addActionListener(this);
		
		// Dialog Box
		c.gridx = 0;
		c.gridy = 4;
		c.gridwidth = 3;
		dialog = new JLabel("Enter in your data...");
		panel.add(dialog, c);
		
		
		// Create GUI
		content.add(panel);
		setContentPane(content);
		setVisible(true);
		
		// Sudoku Variables
		data = new int[9][9];
		solution = new int[9][9];
		for (int i = 0; i < 9; i++ ) {
			Arrays.fill(data[i], -1);
			Arrays.fill(solution[i], -1);
		}
    }
	
	public void actionPerformed(ActionEvent event) {
		JButton button = (JButton) event.getSource();
		
		if (button == solve) {
			try {
				// Get Data
				addData();
			
				// Do the Algorithms
				long start = System.currentTimeMillis();
				AlgorithmPOE poe = new AlgorithmPOE(data);
				solution = poe.solve();
				long stop = System.currentTimeMillis();
				print(solution);
				dialog.setText((stop - start) + " ms");
			} catch(NoSolutionException e) {
				dialog.setText("There is no solution to this puzzle.");
			} catch(NumberFormatException nfe) {
				dialog.setText("You must enter integers between 1 and 9.");
			}
		}
		if (button == clear) {
			for (int i = 0; i < 9; i++) {
				Arrays.fill(data[i], -1);
				Arrays.fill(solution[i], -1);
				for (int j = 0; j < 9; j++) {
					info[i][j].setText("");
				}
			}
			dialog.setText("Enter in you data...");
		}
		if (button == reset) {
			for (int i = 0; i < 9; i++) {
				Arrays.fill(solution[i], -1);
				for (int j = 0; j < 9; j++) {
					info[i][j].setText("");
				}
			}
			print(data);
			dialog.setText("Back where you started!");
		}
    }
	
	public void addData() throws NumberFormatException {
		for (int i = 0; i < 9; i++) {
			for (int j = 0; j < 9; j++) {
				String s = info[i][j].getText();
				try {
					int num = Integer.parseInt(s);
					data[i][j] = num-1;
				} catch(NumberFormatException nfe) {
					if (!s.equals("")) {
						throw nfe;
					}
				}
				if (data[i][j] < -1 || data[i][j] > 8) {
					throw new NumberFormatException();
				}
			}
		}
	}
	
	public void print(int[][] x) {
		for (int i = 0; i < 9; i++) {
			for (int j = 0; j < 9; j++) {
				if (x[i][j] != -1) {
					info[i][j].setText((x[i][j]+1) + "");
				}
			}
		}
	}
}