//
//	Tetris game
//

import java.awt.*;
import java.awt.event.*;

class Tetris extends Frame {

	public static void main(String [] args)
		{ Tetris world = new Tetris(); world.show(); }

		// data fields
	public static final int FrameWidth = 300;
	public static final int FrameHeight = 400;
	private PieceMover player;
	
	public Tetris () 
	{
		setSize (FrameWidth, FrameHeight);
		setTitle("Tetris");

		addKeyListener (new keyDown());
		//requestFocus();
		player = new PieceMover(this);
		player.start();
	}
	
		// interface point between two threads
	private int currentCommand = Piece.Down;

	public synchronized int getCommand(int nextCommand) {
		int oldCommand = currentCommand;
		currentCommand = nextCommand;
		return oldCommand;
		}
			
	private class keyDown extends KeyAdapter {
		public void keyPressed (KeyEvent e) {
			char key = e.getKeyChar();
			switch (key) {
				case 'g': player.newGame(); break;
				case 'j': getCommand(Piece.Left); break;
				case 'k': getCommand(Piece.Rotate); break;
				case 'l': getCommand(Piece.Right); break;
				case 'q': System.exit(0);
				}
			}
		}
	
	public void update (Graphics g)
	{
		Image buffer = createImage (FrameWidth, FrameHeight);
		Graphics sg = buffer.getGraphics();
		sg.clearRect(0, 0, FrameWidth, FrameHeight);
		player.paint(sg);
		g.drawImage (buffer, 0, 0, this);
	}
}

class PieceMover extends Thread {

		// private data fields
	private Tetris controller;
	private Color table[][];
	private Piece currentPiece;
	private int score = 0;
	
		// constructor
	public PieceMover (Tetris t)
	{
		controller = t;
		table = new Color[15][30];
		newGame();
	}
	
		// thread starting point
	public void run ()
	{
		while (dropPiece()) { }
	}

		// other methods
	public void newGame () 
	{
		for (int i = 0; i  < 30; i++)
			for (int j = 0; j < 15; j++)
				table[j][i] = Color.white;
	}
	
	public void paint (Graphics g)
	{
		for (int i = 0; i < 30; i++)
			for (int j = 0; j < 15; j++) {
				g.setColor(table[j][i]);
				g.fillRect(20+10*j, 350-10*i, 10, 10);
				}
		g.setColor(Color.blue);
		g.drawString("Score " + score, 200, 200);
	}

	private boolean dropPiece ()
	{
		int piecetype = 1 + (int) (7 * Math.random());
		currentPiece = new Piece(piecetype);
		if (! currentPiece.move(Piece.Down, table))
			return false;
		int command = controller.getCommand(Piece.Down);
		while (currentPiece.move(command, table)) {
			controller.repaint();
			yield();
			try {
				sleep(100);
				} catch(InterruptedException e) { }
			command = controller.getCommand(Piece.Down);
			}
		// piece cannot move, check score
		checkScore();
		return true;
	}
	
	private void checkScore() 
	{
		for (int i = 0; i < 30; i++) {
			boolean scored = true;
			for (int j = 0; j < 15; j++)
				if (table[j][i] == Color.white)
					scored = false;
			if (scored) {
				score += 10;
				moveDown(i);
				i = i - 1; // check row again
				}
			}
	}

	private void moveDown (int start)
	{
		for (int i = start; i < 30; i++)
			for (int j = 0; j < 15; j++)
				if (i < 29)
					table[j][i] = table[j][i+1];
				else
					table[j][i] = Color.white;
	}
}