src/main/java/org/hedgecode/chess/tcd/TCDParser.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.tcd;
  18
  19 import org.hedgecode.chess.position.Castle;
  20 import org.hedgecode.chess.position.Color;
  21 import org.hedgecode.chess.position.ParseException;
  22 import org.hedgecode.chess.position.Parser;
  23 import org.hedgecode.chess.position.Position;
  24 import org.hedgecode.chess.position.Positions;
  25 import org.hedgecode.chess.position.Square;
  26
  27 /**
  28  * Tiny Chess Diagram (TCD) parser.
  29  *
  30  * @author Dmitry Samoshin aka gotty
  31  */
  32 public final class TCDParser implements Parser {
  33
  34     private static Parser _instance = new TCDParser();
  35
  36     private TCDParser() {
  37     }
  38
  39     private final class TCDIterator {
  40
  41         private byte[] bytes;
  42         private int pos;
  43         private boolean isHighPart;
  44
  45         TCDIterator(byte[] bytes) {
  46             this.bytes = bytes;
  47             this.pos = 0;
  48             this.isHighPart = true;
  49         }
  50
  51         boolean hasNext() {
  52             return (bytes.length > pos + 1) || (isHighPart && bytes.length > pos);
  53         }
  54
  55         boolean isLast() {
  56             return !isHighPart && (bytes.length - 1 == pos);
  57         }
  58
  59         byte next() throws ParseException {
  60             isHighPart = !isHighPart;
  61             if (isHighPart)
  62                 pos++;
  63             return current();
  64         }
  65
  66         byte current() throws ParseException {
  67             if (bytes.length <= pos)
  68                 throw new ParseException("parse.tcd.index.out.of.bounds");
  69             byte frame = bytes[pos];
  70             if (isHighPart)
  71                 frame = (byte) (frame >> TCD.FRAME_LENGTH);
  72             return (byte) (frame & TCD.FRAME_MASK);
  73         }
  74     }
  75
  76     @Override
  77     public Position parse(String string) throws ParseException {
  78         return parse(
  79                 string.getBytes()
  80         );
  81     }
  82
  83     public Position parse(byte[] bytes) throws ParseException {
  84         TCD.replaceFrom(bytes);
  85         if (!TCD.isValid(bytes))
  86             throw new ParseException("parse.tcd.invalid.bytes");
  87         TCDIterator iterator = new TCDIterator(bytes);
  88         return _parse(iterator);
  89     }
  90
  91     private Position _parse(TCDIterator iterator) throws ParseException {
  92         Position position;
  93
  94         byte curr = iterator.current();
  95         byte next = iterator.next();
  96
  97         if (TCD.isBlackWhite(curr, next)) {
  98             position = Positions.INITIAL.getPosition();
  99             curr = iterator.next();
 100             next = iterator.next();
 101         } else {
 102             position = Positions.EMPTY.getPosition();
 103             boolean isWhiteAssigned = false, isBlackAssigned = false;
 104             while (!isWhiteAssigned || !isBlackAssigned) {
 105                 switch (curr) {
 106                     case TCD.WHITE:
 107                         _parsePieces(Color.WHITE, position, iterator);
 108                         isWhiteAssigned = true;
 109                         break;
 110                     case TCD.BLACK:
 111                         _parsePieces(Color.BLACK, position, iterator);
 112                         isBlackAssigned = true;
 113                         break;
 114                     default:
 115                         throw new ParseException("parse.tcd.incorrect.color");
 116                 }
 117                 curr = iterator.current();
 118                 next = iterator.next();
 119             }
 120         }
 121
 122         if (!TCD.isWhiteBlack(curr, next))
 123             throw new ParseException("parse.tcd.incorrect.end");
 124
 125         _parseAddition(position, iterator);
 126
 127         return position;
 128     }
 129
 130     private void _parsePieces(Color color, Position position, TCDIterator iterator) throws ParseException {
 131         byte piece = iterator.current();
 132         while (TCD.isNotColor(piece)) {
 133             int pieceCount = iterator.next() + 1;
 134             for (int i = 0; i < pieceCount; ++i) {
 135                 Square square = _parseSquare(iterator);
 136                 switch (piece) {
 137                     case TCD.PAWN:
 138                         position.setPawn(color, square);
 139                         break;
 140                     case TCD.KNIGHT:
 141                         position.setKnight(color, square);
 142                         break;
 143                     case TCD.BISHOP:
 144                         position.setBishop(color, square);
 145                         break;
 146                     case TCD.ROOK:
 147                         position.setRook(color, square);
 148                         break;
 149                     case TCD.QUEEN:
 150                         position.setQueen(color, square);
 151                         break;
 152                     case TCD.KING:
 153                         position.setKing(color, square);
 154                         break;
 155                     default:
 156                         throw new ParseException("parse.tcd.incorrect.piece");
 157                 }
 158             }
 159             piece = iterator.next();
 160         }
 161     }
 162
 163     private void _parseAddition(Position position, TCDIterator iterator) throws ParseException {
 164         if (iterator.hasNext()) {
 165             byte frame = iterator.next();
 166             if (iterator.isLast() && frame != TCD.END) {
 167                 throw new ParseException("parse.tcd.incorrect.end");
 168             } else {
 169                 boolean isEndPosition = false;
 170                 while (!isEndPosition) {
 171                     switch (frame) {
 172                         case TCD.MOVE:
 173                             position.setMove(
 174                                     _parseMove(iterator)
 175                             );
 176                             break;
 177                         case TCD.CASTLE_WHITE:
 178                             position.setCastle(
 179                                     Color.WHITE, _parseCastle(iterator)
 180                             );
 181                             break;
 182                         case TCD.CASTLE_BLACK:
 183                             position.setCastle(
 184                                     Color.BLACK, _parseCastle(iterator)
 185                             );
 186                             break;
 187                         case TCD.EN_PASSANT:
 188                             position.setEnPassant(
 189                                     _parseSquare(iterator)
 190                             );
 191                             break;
 192                         case TCD.HALFMOVE:
 193                             position.setHalfMove(
 194                                     _parseNumber(iterator)
 195                             );
 196                             break;
 197                         case TCD.FULLMOVE:
 198                             position.setFullMove(
 199                                     _parseNumber(iterator)
 200                             );
 201                             break;
 202                         default:
 203                             throw new ParseException("parse.tcd.incorrect.addition");
 204                     }
 205                     isEndPosition = true;
 206                     if (iterator.hasNext()) {
 207                         frame = iterator.next();
 208                         if (iterator.isLast() && frame != TCD.END) {
 209                             throw new ParseException("parse.tcd.incorrect.end");
 210                         }
 211                         isEndPosition = iterator.isLast();
 212                     }
 213                 }
 214             }
 215         }
 216     }
 217
 218     private Square _parseSquare(TCDIterator iterator) throws ParseException {
 219         byte vl = iterator.next();
 220         byte hl = iterator.next();
 221         return Square.getSquare(vl, hl);
 222     }
 223
 224     private Color _parseMove(TCDIterator iterator) throws ParseException {
 225         byte frame = iterator.next();
 226         if (TCD.isNotColor(frame))
 227             throw new ParseException("parse.tcd.incorrect.move.color");
 228         return frame == TCD.WHITE ? Color.WHITE : Color.BLACK;
 229     }
 230
 231     private Castle _parseCastle(TCDIterator iterator) throws ParseException {
 232         byte frame = iterator.next();
 233         if (TCD.isNotCastle(frame))
 234             throw new ParseException("parse.tcd.incorrect.castle");
 235         Castle castle = Castle.NONE;
 236         switch (frame) {
 237             case TCD.CASTLE_KING:
 238                 castle = Castle.KING;
 239                 break;
 240             case TCD.CASTLE_QUEEN:
 241                 castle = Castle.QUEEN;
 242                 break;
 243             case TCD.CASTLE_BOTH:
 244                 castle = Castle.BOTH;
 245                 break;
 246         }
 247         return castle;
 248     }
 249
 250     private int _parseNumber(TCDIterator iterator) throws ParseException {
 251         return iterator.next() << (2 * TCD.FRAME_LENGTH)
 252                 | iterator.next() << TCD.FRAME_LENGTH
 253                 | iterator.next();
 254     }
 255
 256     public static Parser getInstance() {
 257         return _instance;
 258     }
 259
 260
 261     public static void main(String[] args) throws ParseException {
 262         //Position position = getInstance().parse("A7ONMILHJJIFCJEDO0ECFD0OvFV+4fnNQwOYoWaG-h5pgG");
 263         //Position position = getInstance().parse("xG");
 264         Position position = getInstance().parse("A7ONMILHJJIFCJEDO0ECFDGOvFV+4fnNQwOYoWaG-h5pgG");
 265         System.out.println(position);
 266     }
 267
 268 }