import java.awt.Container;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.event.ChangeListener;
import javax.swing.event.ChangeEvent;
import javax.swing.*;

// package life;

public class MainApp {
	static JButton[][] gridCell;
	static JLabel turnCountDisplay = new JLabel("0",SwingConstants.CENTER);
	static int rows;
	static int turnCount = 0;
	static int turnSpeed = 2000;
	static boolean running = false;
	static ActionListener taskPerformer = new ActionListener() {
		public void actionPerformed(ActionEvent evt) {
			doUpdate(gridCell);
			turnCount++;
			turnCountUpdate();
		}
	};

	public static void main(String[] args) {
		if (args.length > 0) {
			try {
				rows = Integer.parseInt(args[0]);
			} catch (NumberFormatException except) {
				System.err.println("The first parameter should be a number");
				System.exit(0);
			}
		} else {
			rows = 40;
		}
		javax.swing.SwingUtilities.invokeLater(new Runnable() {
			public void run() {
				if (rows > 2) {
					lifeWindow(rows);
				} else {
					System.out.println("Must choose grid size of at least 3");
				}
			}
		});
	}

	static Timer t = new Timer(turnSpeed, taskPerformer);

	static class ButtonListener implements ActionListener {
		public void actionPerformed(ActionEvent event) {
			t.setInitialDelay(0);
			JButton sent = (JButton)event.getSource(); // the button pressed
			String label = sent.getText();           // the button's label
			if (label.equals("Clear") && !running) {
				turnCount = 0;
				turnCountUpdate();
				for (int i=0; i < rows; i++) {
					for (int j=0; j < rows; j++) {
						gridCell[i][j].setBackground(Color.gray);
					}
				}
				t.setRepeats(true);
			} else if (label.equals("Step") && !running) {
				running = true;
				t.setRepeats(false);
				t.start();
				running = false;
			} else if (label.equals("Run") && !running) {
				sent.setText("Pause");
				t.setRepeats(true);
				t.start();
				running = true;
			} else if (label.equals("Pause")) {
				sent.setText("Run");
				t.stop();
				running = false;
			} else if (label.equals("Stop") && !running) {
				System.exit(0);
			}
		}
	}


	public static void turnCountUpdate() {
		turnCountDisplay.setText(String.valueOf(turnCount));
	}

	public static void doUpdate(JButton[][] gridCell) {
		int[][] hold = new int[rows][rows];
		for (int i=0; i < rows; i++) {
			for (int j=0; j < rows; j++) {
				hold[i][j] = getColourValue(gridCell[i][j]);
			}
		}
		processValues(hold);
		for (int i=0; i < rows; i++) {
			for (int j=0; j < rows; j++) {
				gridCell[i][j] = putColourValue(hold[i][j]);
			}
		}
	}

	public static void processValues(int[][] values) {
		int[] surroundingCellData = new int[8];
		for (int i=0; i < rows; i++) {
			for (int j=0; j < rows; j++) {
				surroundingCellData[0] = values[transCoOrd(i-1)][transCoOrd(j-1)];
				surroundingCellData[1] = values[transCoOrd(i-1)][transCoOrd( j )];
				surroundingCellData[2] = values[transCoOrd(i-1)][transCoOrd(j+1)];
				surroundingCellData[3] = values[transCoOrd( i )][transCoOrd(j-1)];
				surroundingCellData[4] = values[transCoOrd( i )][transCoOrd(j+1)];
				surroundingCellData[5] = values[transCoOrd(i+1)][transCoOrd(j-1)];
				surroundingCellData[6] = values[transCoOrd(i+1)][transCoOrd( j )];
				surroundingCellData[7] = values[transCoOrd(i+1)][transCoOrd(j+1)];

				int redCount = 0;
				int greenCount = 0;

				for (int k=0; k < surroundingCellData.length; k++) {
					if (surroundingCellData[k] == 1)		{ redCount++;   }
					else if (surroundingCellData[k] == 2)	{ greenCount++; }
				}
				if (((redCount + greenCount) >= 4) || ((redCount + greenCount) <= 1)) {
					values[i][j] = 0;
				} else if (((redCount + greenCount) == 3) && (values[i][j] == 0)) {
					if (redCount > greenCount) { values[i][j] = 1; }
					else { values[i][j] = 2; }
				}

			}
		}
	}

	public static int transCoOrd(int CoOrd) {
		if (CoOrd == -1) {
			CoOrd = CoOrd + rows;
		} else if (CoOrd == rows) {
			CoOrd = CoOrd - rows;
		}
		return CoOrd;
	}

	public static int getColourValue(JButton button) {
		if (button.getBackground() == Color.red) {
			return 1;
		} else if (button.getBackground() == Color.green) {
			return 2;
		} else {
			return 0;
		}
	}

	public static JButton putColourValue(int colour) {
		JButton newButton = new JButton();
		if (colour == 1) {
			newButton.setBackground(Color.red);
		} else if (colour == 2) {
			newButton.setBackground(Color.green);
		} else {
			newButton.setBackground(Color.gray);
		}
		return newButton;
	}

	public static void lifeWindow(int rows) {
		gridCell = new JButton[rows][rows];
			MouseButtonControl mouseListen = new MouseButtonControl();
			for (int i=0; i < rows; i++) {
				for (int j=0; j < rows; j++) {
					gridCell[i][j] = new JButton();
					gridCell[i][j].addMouseListener(mouseListen);
				}
			}

		JButton clearBtn = new JButton("Clear");
		JButton stepBtn = new JButton("Step");
		JButton runBtn = new JButton("Run");
		JButton stopBtn = new JButton("Stop");
			ButtonListener listen = new ButtonListener();
			clearBtn.addActionListener(listen);
			stepBtn.addActionListener(listen);
			runBtn.addActionListener(listen);
			stopBtn.addActionListener(listen);

		JFrame frame = new JFrame();
			frame.setSize(500,500);
			Container contentPane = frame.getContentPane();
				JPanel cellGrid = new JPanel();
				JPanel buttonPanel = new JPanel();

		cellGrid.setLayout(new GridLayout(rows,rows,0,0));
			for (int i=0; i < rows; i++) {
				for (int j=0; j < rows; j++) {
					cellGrid.add(gridCell[i][j]);
					gridCell[i][j].setBackground(Color.gray);
				}
			}
			cellGrid.setBorder(BorderFactory.createEmptyBorder(0,10,0,0));

		JSlider slide = new JSlider(JSlider.VERTICAL,1,10,1);
			slide.setMajorTickSpacing(1);
			slide.setMinorTickSpacing(1);
			slide.setPaintTicks(true);
			slide.setPaintLabels(true);
			slide.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));

		buttonPanel.add(clearBtn);
		buttonPanel.add(stepBtn);
		buttonPanel.add(runBtn);
		buttonPanel.add(stopBtn);

		contentPane.add(turnCountDisplay,BorderLayout.NORTH);
		contentPane.add(cellGrid,BorderLayout.CENTER);
		contentPane.add(slide,BorderLayout.EAST);
		contentPane.add(buttonPanel,BorderLayout.SOUTH);

		slide.addChangeListener(new ChangeValue());
		frame.setVisible(true);
	}

	static class ChangeValue implements ChangeListener {

		public void stateChanged(ChangeEvent expn) {

			JSlider source = (JSlider)expn.getSource();
			if (!source.getValueIsAdjusting()) {
					t.setDelay(2000 / (int)source.getValue());
			}
		}
	}

	static class MouseButtonControl extends MouseAdapter {

		public void mousePressed(MouseEvent event) {
			JButton cell = (JButton)event.getSource();
			if (!running) {
				if (SwingUtilities.isLeftMouseButton(event)) {
					cell.setBackground(Color.red);
				} else if (SwingUtilities.isRightMouseButton(event)) {
					cell.setBackground(Color.green);
				} else {
					cell.setBackground(Color.gray);
				}
			}
		}
	}
}