chesshog-db-etude/src/main/java/org/hedgecode/chess/EtudeUtils.java

   1 /*
   2  * Copyright (c) 2018. Developed by Hedgecode.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *   http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.hedgecode.chess;
  18
  19 import java.math.BigInteger;
  20 import java.util.Arrays;
  21 import java.util.HashMap;
  22 import java.util.Map;
  23
  24 import org.hedgecode.chess.position.Color;
  25 import org.hedgecode.chess.position.ColorPiece;
  26 import org.hedgecode.chess.position.Piece;
  27 import org.hedgecode.chess.position.Position;
  28 import org.hedgecode.chess.position.Positions;
  29 import org.hedgecode.chess.position.Square;
  30 import org.hedgecode.chess.position.SquareSort;
  31
  32 /**
  33  *
  34  *
  35  * @author Dmitry Samoshin aka gotty
  36  */
  37 public final class EtudeUtils {
  38
  39     private static final byte PIECE_MASK   = 0b1111;
  40     private static final byte PIECE_LENGTH = 4;
  41
  42     private static final byte NUM_WHITE_PAWN   = 0;
  43     private static final byte NUM_WHITE_KNIGHT = 1;
  44     private static final byte NUM_WHITE_BISHOP = 2;
  45     private static final byte NUM_WHITE_ROOK   = 3;
  46     private static final byte NUM_WHITE_QUEEN  = 4;
  47
  48     private static final byte NUM_BLACK_PAWN   = 5;
  49     private static final byte NUM_BLACK_KNIGHT = 6;
  50     private static final byte NUM_BLACK_BISHOP = 7;
  51     private static final byte NUM_BLACK_ROOK   = 8;
  52     private static final byte NUM_BLACK_QUEEN  = 9;
  53
  54     private static final byte BLOB_PIECE_EMPTY  = 0b0000;
  55
  56     private static final byte BLOB_WHITE_PAWN   = 0b0001;
  57     private static final byte BLOB_WHITE_KNIGHT = 0b0010;
  58     private static final byte BLOB_WHITE_BISHOP = 0b0011;
  59     private static final byte BLOB_WHITE_ROOK   = 0b0100;
  60     private static final byte BLOB_WHITE_QUEEN  = 0b0101;
  61     private static final byte BLOB_WHITE_KING   = 0b0110;
  62
  63     private static final byte BLOB_BLACK_PAWN   = 0b1001;
  64     private static final byte BLOB_BLACK_KNIGHT = 0b1010;
  65     private static final byte BLOB_BLACK_BISHOP = 0b1011;
  66     private static final byte BLOB_BLACK_ROOK   = 0b1100;
  67     private static final byte BLOB_BLACK_QUEEN  = 0b1101;
  68     private static final byte BLOB_BLACK_KING   = 0b1110;
  69
  70     private static final Map<ColorPiece, Byte> PIECE_NUMBERS = new HashMap<ColorPiece, Byte>() {
  71         {
  72             put(ColorPiece.WHITE_PAWN, NUM_WHITE_PAWN);     put(ColorPiece.BLACK_PAWN, NUM_BLACK_PAWN);
  73             put(ColorPiece.WHITE_KNIGHT, NUM_WHITE_KNIGHT); put(ColorPiece.BLACK_KNIGHT, NUM_BLACK_KNIGHT);
  74             put(ColorPiece.WHITE_BISHOP, NUM_WHITE_BISHOP); put(ColorPiece.BLACK_BISHOP, NUM_BLACK_BISHOP);
  75             put(ColorPiece.WHITE_ROOK, NUM_WHITE_ROOK);     put(ColorPiece.BLACK_ROOK, NUM_BLACK_ROOK);
  76             put(ColorPiece.WHITE_QUEEN, NUM_WHITE_QUEEN);   put(ColorPiece.BLACK_QUEEN, NUM_BLACK_QUEEN);
  77         }
  78     };
  79
  80     private static final Map<ColorPiece, Byte> BLOB_PIECES = new HashMap<ColorPiece, Byte>() {
  81         {
  82             put(ColorPiece.WHITE_PAWN, BLOB_WHITE_PAWN);     put(ColorPiece.BLACK_PAWN, BLOB_BLACK_PAWN);
  83             put(ColorPiece.WHITE_KNIGHT, BLOB_WHITE_KNIGHT); put(ColorPiece.BLACK_KNIGHT, BLOB_BLACK_KNIGHT);
  84             put(ColorPiece.WHITE_BISHOP, BLOB_WHITE_BISHOP); put(ColorPiece.BLACK_BISHOP, BLOB_BLACK_BISHOP);
  85             put(ColorPiece.WHITE_ROOK, BLOB_WHITE_ROOK);     put(ColorPiece.BLACK_ROOK, BLOB_BLACK_ROOK);
  86             put(ColorPiece.WHITE_QUEEN, BLOB_WHITE_QUEEN);   put(ColorPiece.BLACK_QUEEN, BLOB_BLACK_QUEEN);
  87             put(ColorPiece.WHITE_KING, BLOB_WHITE_KING);     put(ColorPiece.BLACK_KING, BLOB_BLACK_KING);
  88         }
  89     };
  90
  91     public static BigInteger hashPosition(Position position) {
  92         StringBuilder sb = new StringBuilder();
  93         sb.append(
  94                 numSquare(
  95                         kingSquare(Color.WHITE, position)
  96                 )
  97         ).append(
  98                 numSquare(
  99                         kingSquare(Color.BLACK, position)
 100                 )
 101         );
 102         int empty = 0;
 103         for (Map.Entry<Square, ColorPiece> entry : position.getSquares(SquareSort.A8H1).entrySet()) {
 104             ColorPiece colorPiece = entry.getValue();
 105             if (colorPiece != null && !Piece.KING.equals(colorPiece.piece())) {
 106                 if (empty > 0)
 107                     sb.append(empty);
 108                 sb.append(
 109                         PIECE_NUMBERS.get(colorPiece)
 110                 );
 111                 empty = 0;
 112             } else {
 113                 ++empty;
 114             }
 115         }
 116         if (empty > 0)
 117             sb.append(empty);
 118
 119         return new BigInteger(
 120                 sb.toString() /* todo: SQL: NUMERIC(64,0) */
 121         );
 122     }
 123
 124     public static byte[] blobPosition(Position position) {
 125         byte[] blob = new byte[Square.getSize() * Square.getSize()];
 126         int i = 0;
 127         for (Map.Entry<Square, ColorPiece> entry : position.getSquares(SquareSort.A8H1).entrySet()) {
 128             ColorPiece colorPiece = entry.getValue();
 129             blob[i++] = colorPiece != null ? BLOB_PIECES.get(colorPiece) : BLOB_PIECE_EMPTY;
 130         }
 131         return compress(blob);
 132     }
 133
 134     private static Square kingSquare(Color color, Position position) {
 135         Square kingSquare = null;
 136
 137         Map<Square, ColorPiece> king = position.getSquarePieces(color, Piece.KING);
 138
 139         if (king.isEmpty() || king.size() > 1)
 140             throw new RuntimeException("Incorrect position"); // todo
 141
 142         for (Square square : king.keySet()) {
 143             kingSquare = square;
 144         }
 145         return kingSquare;
 146     }
 147
 148     private static int numSquare(Square square) {
 149         int v = square.getV() + 1;
 150         int h = Square.getSize() - square.getH();
 151         return Square.getSize() * (h - 1) + v;
 152     }
 153
 154     private static byte[] compress(byte[] bytes) {
 155         byte[] cmpBytes = new byte[bytes.length / 2];
 156         byte high, low;
 157         int i = 0;
 158         for (int j = 0; j < cmpBytes.length; ++j) {
 159             high = (byte) ((bytes[i++] & PIECE_MASK) << PIECE_LENGTH);
 160             low  = (byte) (bytes[i++] & PIECE_MASK);
 161             cmpBytes[j] = (byte) (high | low);
 162         }
 163         return cmpBytes;
 164     }
 165
 166     private EtudeUtils() {
 167         throw new AssertionError(
 168                 "No org.hedgecode.chess.EtudeUtils instances!"
 169         );
 170     }
 171
 172
 173     public static void main(String... args) {
 174         System.out.println(
 175                 hashPosition(Positions.INITIAL.getPosition())
 176         );
 177         System.out.println(
 178                 Arrays.toString(blobPosition(Positions.INITIAL.getPosition()))
 179         );
 180     }
 181
 182 }