/**
 *   $Id: Board.java 148 2008-04-25 22:05:48Z mbroeker $
 *  $URL: http://localhost/svn/eclipse/Schachspiel/trunk/org/homelinux/largo/games/board/Board.java $
 */

package org.homelinux.largo.games.board;

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.util.Vector;

public class Board extends Canvas {
	static final long serialVersionUID = 140208;

	protected boolean UNDO_DEBUG  = false;

	protected Piece board_pieces[];
	private Piece pieces[];

	protected Vector<History> stack;
	protected int moveNr;

	protected static final int EMPTY = 0;

	Color color_black;
	Color color_white;

	int iHeight;
	int iWidth;
	int xPos;
	int yPos;

	boolean black;
	boolean blacksTurn;

	MouseListener listener = null;

	/**
	 * The init method initializes an empty board with a history.
	 */
	public void init() {
		int i;
		pieces = new Piece[64];

		for (i = 0; i < 64; i++) {
			pieces[i] = new Piece(null, null, EMPTY, 0);
		}

		xPos = 0;
		yPos = 0;

		black = false;
		blacksTurn = false;
		board_pieces = getPieces(pieces);
		stack = new Vector<History>();
		moveNr = 0;
	}

	public Board (int w, int h) {
		iWidth = w;
		iHeight = h;
		color_white = new Color (255, 255, 255);
		color_black = new Color (50, 100, 200);
		setPreferredSize (new Dimension(8 * iWidth, 8 * iHeight));

		init();
		listener = new MouseListener(iWidth, iHeight);
		addMouseListener(listener);
	}

	/**
	 * getPiece returns a Piece-Object from the Board Cache. It might not be visible on the current board.
	 */
	public Piece getPiece(int t) {
		return pieces[t];
	}

	/**
	 * setPiece sets a Piece-Object into the Board Cache and will not be visible.
	 */
	protected void setPiece(int t, Piece p) {
		pieces[t] = p;
	}

	protected Piece[] getPieces() {
		return getPieces(pieces);
	}

	private Piece[] getPieces(Piece[] which_pieces) {
		Piece[] p = new Piece[64];
		int i;

		for ( i=0;i<64;i++)
			p[i] = new Piece(which_pieces[i]);

		return p;
	}

	protected void setPieces(Piece[] p) {
		pieces = p;
	}

	/**
	 * needed in paint(Graphics g)
	 */
	private Image getBoardImage (int i) {
		return board_pieces[i].image;
	}

	/**
	 * getMouseListener returns a valid MouseListener for this Board.
	 */
	public MouseListener getMouseListener() {
		return listener;
	}

	/**
	 * currentMove returns the current stack.size().
	 */
	public int currentMove() {
		return stack.size();
	}

	/**
	 * returns the color of piece[i].
	 */
	public String getColor(int i) {
		return pieces[i].color;
	}

	/**
	 * returns the current Value of a particular piece.
	 */
	public int getValue(int i) {
		return pieces[i].value;
	}

	/**
	 * Defined Integer Constants: EMTPY = 0
	 */
	public int getType(int i) {
		return pieces[i].type;
	}

	public boolean isEmpty (int i) {
		if (pieces[i].type == EMPTY)
			return true;
		return false;
	}

	boolean BoardisEmpty (int i) {
		if (board_pieces[i].type == EMPTY)
			return true;
		return false;
	}

	/**
	 * blacksTurn = true  -> Black moves
	 * blacksTurn = false -> White moves
	 */
	public boolean isBlacksTurn() {
		return blacksTurn;
	}

	public void setBlacksTurn(boolean b) {
		blacksTurn = b;
	}

	/**
	 * returns true, when piece[i] is white
	 */
	public boolean isWhite(int i) {
		if ( isEmpty(i) )
			return false;

		if ( pieces[i].color.equals ("white") )
			return true;
		return false;
	}

	/**
	 * returns true, when piece[i] is black
	 */
	public boolean isBlack(int i) {
		if ( isEmpty(i) )
			return false;

		if ( pieces[i].color.equals ("black") )
			return true;
		return false;
	}

	/**
	 * returns true, when both pieces have opposite colors
	 */
	public boolean isEnemy(int t, int o) {
		if ( isEmpty(t) )
			return false;

		if (!pieces[t].color.equals (pieces[o].color) )
			return true;
		return false;
	}

	/**
	 * returns true, when both pieces have the same color
	 */
	public boolean isSamePiece(int t, int o) {
		if ( isEmpty(t) )
			return false;

		if (pieces[t].color.equals (pieces[o].color) )
			return true;
		return false;
	}

	/**
	 * This function checks for the color of the piece at piece[i] and returns true,
	 * if the color matches the current Turn.
	 */
	public boolean validTurn(int i) {
		if ( isEmpty(i) )
			return false;

		if ( getColor(i).equals("white") && isBlacksTurn() )
			return false;
		if ( getColor(i).equals("black") && !isBlacksTurn() )
			return false;
		return true;
	}

	/**
	 * simulates a "valid" move or returns false.
	 * all changes are relative to pieces and will not be painted.
	 * This method sets internal variables for the rochade() method, which will be overidden.
	 */
	public boolean simulateMove(int t, int o) {
		if ( !validMove(t, o) ) {
			return false;
		}

		push(pieces[t], t, pieces[o], o);

		pieces[t] = new Piece(pieces[o]);
		pieces[o] = new Piece(null, null, EMPTY, 0);

		return true;
	}

	/**
	 * Moves a Piece on the Board at Point p
	 */
	public boolean move (Point p) {
		int t;
		int o;

		t = (p.endy * 8) + p.endx;
		o = (p.starty * 8) + p.startx;

		if ( t < 0 || t > 63 )
			return false;
		if ( o < 0 || o > 63 )
			return false;

		if (validTurn(o))
			return doMove (t, o);

		System.out.println("It's not your turn!");
		return false;
	}

	/**
	 * Moves one half-move backward.
	 */
	public void backwards() {
		History h1 = null;
		History h2 = null;

		if ( moveNr < 2)
			return;

		moveNr -= 2;

		h1 = stack.elementAt(moveNr);
		h2 = stack.elementAt(moveNr+1);

		board_pieces[h1.pos] = h1.piece;
		board_pieces[h2.pos] = h2.piece;

		repaint();
	}

	/**
	 * Moves one half-move forward.
	 */
	public void forward() {
		History h1 = null;
		History h2 = null;

		if ( moveNr > stack.size()-2 )
			return;

		h1 = stack.elementAt(moveNr);
		h2 = stack.elementAt(moveNr+1);

		board_pieces[h1.pos] = h2.piece;
		board_pieces[h2.pos] = new Piece(null, null, EMPTY, 0);

		moveNr += 2;
		repaint();
	}

	/**
	 * pushes 2 pieces onto the stack.
	 */
	public void push(Piece p1, int t, Piece p2, int o) {
		stack.add(new History(p1, t, isBlacksTurn()));
		stack.add(new History(p2, o, isBlacksTurn()));
	}

	/**
	 * pop: undo the push operation.
	 */
	public void undo() {
		History h1 = null;
		History h2 = null;
		int size = stack.size();

		if ( size < 2 )
			return;

		h1 = stack.elementAt(size-1);
		h2 = stack.elementAt(size-2);

		pieces[h1.pos] = h1.piece;
		pieces[h2.pos] = h2.piece;

		stack.setSize(size-2);

		/* Reset the current player */
		setBlacksTurn(h2.turn);
	}

	/**
	 * This method must be implemented in your "GameBoard"
	 * Return value:  TRUE: the move IS possible
	 * Return value: FALSE: the move IS NOT possible
	 */
	public boolean validMove(int t, int o) {
		System.out.println("public boolean validMove(int t, int o): Implement me");
		return false;
	}

	/**
	 * This method must be implemented in your "GameBoard"
	 * Return value:  TRUE: the move was performed
	 * Return value: FALSE: the move was not performed
	 */
	public boolean doMove(int t, int o) {
		System.out.println("public boolean doMove(int t, int o): Implement me");
		return false;
	}

	public void update(Graphics g){
		paint(g);
	}

	public void paint (Graphics g) {
		for (int i = 0; i < 8; i++) {
			for (int j = 0; j < 8; j++) {
				if (black == true) {
					g.setColor (color_black);
					g.fillRect (xPos, yPos, iWidth, iHeight);
					black = false;
				} else {
					g.setColor (color_white);
					g.fillRect (xPos, yPos, iWidth, iHeight);
					black = true;
				}
				if ( !BoardisEmpty ((i * 8) + j) )
					g.drawImage (getBoardImage ((i * 8) + j), xPos + 5, yPos, this);
				xPos += iWidth;
			}
			xPos = 0;
			yPos += iHeight;
			black = !black;
		}
		xPos = 0;
		yPos = 0;
	}
}