/**
 *   $Id: ChessBoard.java 152 2008-04-27 02:04:31Z mbroeker $
 *  $URL: http://localhost/svn/eclipse/Schachspiel/trunk/org/homelinux/largo/games/board/chessboard/ChessBoard.java $
 */

package org.homelinux.largo.games.board.chessboard;

import java.awt.Image;

import org.homelinux.largo.games.board.Board;
import org.homelinux.largo.games.board.Piece;
import org.homelinux.largo.utils.ImgComponent;

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

	static final int ROOK = 1;
	static final int KNIGHT = 2;
	static final int BISHOP = 3;
	static final int QUEEN = 4;
	static final int KING = 5;
	static final int PAWN = 6;

	final Piece white_queen = new Piece(new ImgComponent("images/white_queen.png").getImage(),
					"white", QUEEN, 90);
	final Piece black_queen = new Piece(new ImgComponent("images/black_queen.png").getImage(), 
					"black", QUEEN, 90);

	boolean white_rochades_small;
	boolean white_rochades_big;
	boolean black_rochades_small;
	boolean black_rochades_big;

	void initBoard () {
		add (new ImgComponent ("images/black_rook.png").getImage (), 0, "black", ROOK);
		add (new ImgComponent ("images/black_knight.png").getImage (), 1, "black", KNIGHT);
		add (new ImgComponent ("images/black_bishop.png").getImage (), 2, "black", BISHOP);
		add (new ImgComponent ("images/black_queen.png").getImage (), 3, "black", QUEEN);
		add (new ImgComponent ("images/black_king.png").getImage (), 4, "black", KING);
		add (new ImgComponent ("images/black_bishop.png").getImage (), 5, "black", BISHOP);
		add (new ImgComponent ("images/black_knight.png").getImage (), 6, "black", KNIGHT);
		add (new ImgComponent ("images/black_rook.png").getImage (), 7, "black", ROOK);

		for (int i = 0; i < 8; i++)
			add (new ImgComponent ("images/black_pawn.png").getImage (), 8 + i, "black", PAWN);

		add (new ImgComponent ("images/white_rook.png").getImage (), 56, "white", ROOK);
		add (new ImgComponent ("images/white_knight.png").getImage (), 57, "white", KNIGHT);
		add (new ImgComponent ("images/white_bishop.png").getImage (), 58, "white", BISHOP);
		add (new ImgComponent ("images/white_queen.png").getImage (), 59, "white", QUEEN);
		add (new ImgComponent ("images/white_king.png").getImage (), 60, "white", KING);
		add (new ImgComponent ("images/white_bishop.png").getImage (), 61, "white", BISHOP);
		add (new ImgComponent ("images/white_knight.png").getImage (), 62, "white", KNIGHT);
		add (new ImgComponent ("images/white_rook.png").getImage (), 63, "white", ROOK);

		for (int i = 0; i < 8; i++)
			add (new ImgComponent ("images/white_pawn.png").getImage (), 55 - i, "white", PAWN);
	}

	/**
	 * The init method initializes a complete chess board with figures and a history.
	 */
	public void init() {
		super.init();
		initBoard();
		board_pieces = getPieces();
		repaint();
	}

	public ChessBoard (int w, int h) {
		super(w, h);
	}

	void add (Image img, int i, String c, int t) {
		int v = 0;

		switch (t) {
		case ROOK:
			v = 40;
			break;
		case KNIGHT:
			v = 30;
			break;
		case BISHOP:
			v = 30;
			break;
		case QUEEN:
			v = 90;
			break;
		case KING:
			v = 500;
			break;
		case PAWN:
			v = 10;
			break;
		}

		setPiece(i, new Piece(img, c, t, v));
	}

	/**
	 * returns true, when the white king is at pieces[i]
	 */
	public boolean isWhiteKing(int i) {
		if ( isWhite(i) && getType(i) == KING)
			return true;
		return false;
	}

	/**
	 * returns true, when the black king is at pieces[i]
	 */
	public boolean isBlackKing(int i) {
		if ( isBlack(i) && getType(i) == KING)
			return true;
		return false;
	}

	/**
	 * Returns the score of the current position
	 * Every field controlled by [color] gives one point
	 * A King, controlled by [color], gives 10 extra points
	 */
	public int controls(String color) {
		int t, o;
		int value = 0;

		for ( o=0;o<64;o++) {
			if (color.equals(getColor(o))) {
				for (t=0;t<64;t++) {
					if(validMove(t, o)) {
						if ( getType(t) == KING )
							value+=10;
						value++;
					}
				}
			}
		}
		return value;
	}

	/**
	 * Checks, wether this move is possible or not.
	 */
	public boolean validMove (int t, int o) {
		int steps;
		int rows;
		int dx;

		/* Must be here */
		white_rochades_small = false;
		white_rochades_big = false;
		black_rochades_small = false;
		black_rochades_big = false;

		if ( t == o )
			return false;

		if (isSamePiece(t, o))
			return false;

		if (getType(o) == EMPTY)
			return false;

		/*
		 *	00 01 02 03 04 05 06 07
		 *	08 09 10 11 12 13 14 15
		 *	16 17 18 19 20 21 22 23
		 *	24 25 26 27 28 29 30 31
		 *	32 33 34 35 36 37 38 39
		 *	40 41 42 43 44 45 46 47
		 *	48 49 50 51 52 53 54 55
		 *	56 57 58 59 60 61 62 63
		 */

		steps = Math.abs(t-o);
		rows = Math.abs(t/8 - o/8);

		switch( getType(o) ) {
		case ROOK:
			if (steps < 8 && rows == 0 ) {
				if(t>o)
					for ( dx = o+1; dx < t; dx++ ) {
						if ( getColor(dx) != null ) {
							return false;
						}
					}
				else
					for ( dx = o-1; dx > t; dx-- ) {
						if ( getColor(dx) != null ) {
							return false;
						}
					}
				return true;
			}
			if (steps % 8 == 0 ) {
				if ( t>o ) {
					for ( dx = o+8;  dx < t; dx+=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-8;  dx > t; dx-=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				}
				if (steps == 8 && rows == 1)
					return true;
				if (steps == 16 && rows == 2)
					return true;
				if (steps == 24 && rows == 3)
					return true;
				if (steps == 32 && rows == 4)
					return true;
				if (steps == 40 && rows == 5)
					return true;
				if (steps == 48 && rows == 6)
					return true;
				if (steps == 56 && rows == 7)
					return true;
			}
			break;
		case KNIGHT:
			/* works fine */
			if (steps == 6 && rows == 1)
				return true;
			if (steps == 10 && rows == 1)
				return true;
			if (steps == 15 && rows == 2)
				return true;
			if (steps == 17 && rows == 2)
				return true;
			break;
		case BISHOP:
			if (steps % 7 == 0 ) {
				if ( t>o ) {
					for ( dx = o+7;  dx < t; dx+=7 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-7;  dx > t; dx-=7 ) {
						if (getColor(dx) != null)
							return false;
					}
				}
				if (steps == 7 && rows == 1)
					return true;
				if (steps == 14 && rows == 2)
					return true;
				if (steps == 21 && rows == 3)
					return true;
				if (steps == 28 && rows == 4)
					return true;
				if (steps == 35 && rows == 5)
					return true;
				if (steps == 42 && rows == 6)
					return true;
				if (steps == 49 && rows == 7)
					return true;
			}
			if (steps % 9 == 0 ) {
				if ( t>o ) {
					for ( dx = o+9;  dx < t; dx+=9 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-9; dx > t; dx-=9 ) {
						if (getColor(dx) != null)
							return false;
					}
				}
				if (steps == 9 && rows == 1)
					return true;
				if (steps == 18 && rows == 2)
					return true;
				if (steps == 27 && rows == 3)
					return true;
				if (steps == 36 && rows == 4)
					return true;
				if (steps == 45 && rows == 5)
					return true;
				if (steps == 54 && rows == 6)
					return true;
				if (steps == 63 && rows == 7)
					return true;
			}
			break;

		case QUEEN:
			if (steps < 8 && rows == 0 ) {
				if(t>o)
					for ( dx = o+1; dx < t; dx++ ) {
						if ( getColor(dx) != null )
							return false;
					}
				else
					for ( dx = o-1; dx > t; dx-- ) {
						if ( getColor(dx) != null )
							return false;
					}
				return true;
			}

			if (steps % 8 == 0 ) {
				if ( t>o ) {
					for ( dx = o+8;  dx < t; dx+=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-8;  dx > t; dx-=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				}

				if (steps == 8 && rows == 1)
					return true;
				if (steps == 16 && rows == 2)
					return true;
				if (steps == 24 && rows == 3)
					return true;
				if (steps == 32 && rows == 4)
					return true;
				if (steps == 40 && rows == 5)
					return true;
				if (steps == 48 && rows == 6)
					return true;
				if (steps == 56 && rows == 7)
					return true;
			}
			if (steps % 7 == 0 ) {
				if ( t>o ) {
					for ( dx = o+7;  dx < t; dx+=7 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-7;  dx > t; dx-=7 ) {
						if (getColor(dx) != null)
							return false;
					}
				}
				if (steps == 7 && rows == 1)
					return true;
				if (steps == 14 && rows == 2)
					return true;
				if (steps == 21 && rows == 3)
					return true;
				if (steps == 28 && rows == 4)
					return true;
				if (steps == 35 && rows == 5)
					return true;
				if (steps == 42 && rows == 6)
					return true;
				if (steps == 49 && rows == 7)
					return true;
			}

			if (steps % 9 == 0 ) {
				if ( t>o ) {
					for ( dx = o+9;  dx < t; dx+=9 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-9;  dx > t; dx -=9 ) {
						if (getColor(dx) != null)
							return false;
					}
				}
				if (steps == 9 && rows == 1)
					return true;
				if (steps == 18 && rows == 2)
					return true;
				if (steps == 27 && rows == 3)
					return true;
				if (steps == 36 && rows == 4)
					return true;
				if (steps == 45 && rows == 5)
					return true;
				if (steps == 54 && rows == 6)
					return true;
				if (steps == 63 && rows == 7)
					return true;
			}
			break;

		case KING:
			if ( (steps == 1) && (rows == 0) )
				return true;

			if ( (steps == 8) && (rows == 1) )
				return true;

			if ( (steps == 7) && (rows == 1) )
				return true;

			if ( (steps == 9) && (rows == 1) )
				return true;

			if ( (steps == 2) && (rows == 0) ) {
				if ( isWhiteKing(o) ) {		/* White: Rochade */
					if ( isWhiteKing(60) && isEmpty(61) && isEmpty(62) && (t==62) ) {
						if ( (getType(63) == ROOK) && isWhite(63) ) {
							white_rochades_small = true;
							return true;
						}
					}

					if ( isWhiteKing(60) && isEmpty(59) && isEmpty(58) && isEmpty(57) && (t==58) ) {
						if ( (getType(56) == ROOK) && isWhite(56) ) {
							white_rochades_big = true;
							return true;
						}
					}
				}

				if ( isBlackKing(o) ) {		/* Black: Rochade */
					if ( isBlackKing(4) && isEmpty(5) && isEmpty(6) && (t==6) ) {
						if ( (getType(7) == ROOK) && isBlack(7) ) {
							black_rochades_small = true;
							return true;
						}
					}

					if ( isBlackKing(4) && isEmpty(3) && isEmpty(2) && isEmpty(1) && (t==2) ) {
						if ( (getType(0) == ROOK) && isBlack(0) ) {
							black_rochades_big = true;
							return true;
						}
					}
				}
			}
			break;

		case PAWN:
			if (getColor(o).equals("white")) {
				if (steps == 7 && rows == 1 && isEnemy(t, o) && t<o)
					return true;

				if (steps == 9 && rows == 1 && isEnemy(t, o) && t<o)
					return true;
			} else {
				if (steps == 7 && rows == 1 && isEnemy(t, o) && t>o)
					return true;

				if (steps == 9 && rows == 1 && isEnemy(t, o) && t>o)
					return true;
			}

			if (steps % 8 == 0 ) {
				if ( t>o ) {
					for ( dx = o+8;  dx <= t; dx+=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				} else {
					for ( dx = o-8; dx >= t; dx-=8 ) {
						if (getColor(dx) != null)
							return false;
					}
				}

				if (steps == 8 && rows == 1) {
					if ( getColor(o).equals("white") && t < o )
						return true;
					if ( getColor(o).equals("black") && t > o )
						return true;
				}

				if (steps == 16 && rows == 2 && (o>= 8 && o <=15) ) {
					if ( getColor(o).equals("white") && t < o )
						return true;
					if ( getColor(o).equals("black") && t > o )
						return true;
				}

				if (steps == 16 && rows == 2 && (o>=48 && o <=55) ) {
					if ( getColor(o).equals("white") && t < o )
						return true;
					if ( getColor(o).equals("black") && t > o )
						return true;
				}
			}
			break;
		}
		return false;
	}

	/**
	 * This method must be called immediately after isValidMove(t, o)
	 */
	boolean rochade() {
		if (white_rochades_small) {
			setPiece(61, getPiece(63));
			setPiece(63, new Piece(null, null, EMPTY, 0));
			return true;
		}

		if (white_rochades_big) {
			setPiece(59, getPiece(56));
			setPiece(56, new Piece(null, null, EMPTY, 0));
			return true;
		}

		if (black_rochades_small) {
			setPiece(5, getPiece(7));
			setPiece(7, new Piece(null, null, EMPTY, 0));
			return true;
		}

		if (black_rochades_big) {
			setPiece(3, getPiece(0));
			setPiece(0, new Piece(null, null, EMPTY, 0));
			return true;
		}

		return false;
	}

	/**
	 * checks, whether color is in check or not.
	 */
	public boolean isCheck(String color) {
		int i;
		int wking;
		int bking;

		wking = bking = -1;

		for (i=0;i<64;i++) {
			if (isWhiteKing(i)) {
				wking = i;
			}
			if (isBlackKing(i)) {
				bking = i;
			}
		}

		// returns 64 false positives
		if (wking == -1 || bking == -1)
			return true;

		if (color.equals("white")) {
			for (i=0;i<64;i++)
				if (validMove(wking, i)) {
					return true;
				}

			return false;
		}

		if (color.equals("black")) {
			for (i=0;i<64;i++)
				if (validMove(bking, i)) {
					return true;
				}

			return false;
		}
		return false;
	}

	/**
	 * 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 overwritten.
	 */
	public boolean simulateMove(int t, int o) {
		if ( !validMove(t, o) ) {
			return false;
		}

		push(getPiece(t), t, getPiece(o), o);

		if ( getType(o) == PAWN ) {
			if(isBlack(o) && t >=56)
				setPiece(o, new Piece(black_queen));

			if(isWhite(o) && t <=7)
				setPiece(o, new Piece(white_queen));
		}

		setPiece(t, new Piece(getPiece(o)));
		setPiece(o, new Piece(null, null, EMPTY, 0));

		if (isCheck(getColor(t))) {
			/* restore current position */
			if(UNDO_DEBUG)
				print("UNDO", t, o, 0);
			undo();
			return false;
		}

		return true;
	}

	/**
	 * performs a "valid" move or returns false.
	 * all changes are relative to board_pieces and will be painted.
	 */
	public boolean doMove(int t, int o) {
		if ( !validMove(t, o) ) {
			return false;
		}

		push(getPiece(t), t, getPiece(o), o);

		if ( getType(o) == PAWN ) {
			if(isBlack(o) && t >=56)
				setPiece(o, new Piece(black_queen));

			if(isWhite(o) && t <=7)
				setPiece(o, new Piece(white_queen));
		}
		
		setPiece(t, new Piece(getPiece(o)));
		setPiece(o, new Piece(null, null, EMPTY, 0));

		if (rochade())
			System.out.println("Rochade");

		if (isCheck(getColor(t))) {
			// restore current positions
			if(UNDO_DEBUG)
				print("UNDO", t, o, 0);
			undo();
			return false;
		}

		board_pieces = getPieces();
		repaint();

		moveNr = stack.size();

		return true;
	}

	/**
	 * converts the internal representation into normal chess notation and writes it to stdout
	 */
	public void print(String s, int t, int o, int value) {
		int row1, col1, row2, col2;

		row1 = o/8;
		col1 = o-(8*row1);

		row2 = t/8;
		col2 = t-(8*row2);

		System.out.printf("%s: %C%d-%c%d = %3d\n", s,
				('A')+col1, 8-row1,
				('A')+col2, 8-row2, value);
	}
}