chesshog-format/src/main/java/org/hedgecode/chess/fen/FENBuilder.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.fen;
  18
  19 import java.util.Map;
  20
  21 import org.hedgecode.chess.Parsers;
  22 import org.hedgecode.chess.position.Builder;
  23 import org.hedgecode.chess.position.Color;
  24 import org.hedgecode.chess.position.ColorPiece;
  25 import org.hedgecode.chess.position.ParseException;
  26 import org.hedgecode.chess.position.Position;
  27 import org.hedgecode.chess.position.Square;
  28
  29 /**
  30  * Forsyth–Edwards Notation (FEN) builder.
  31  *
  32  * @author Dmitry Samoshin aka gotty
  33  */
  34 public final class FENBuilder implements Builder {
  35
  36     private static Builder _instance = new FENBuilder();
  37
  38     private FENBuilder() {
  39     }
  40
  41     @Override
  42     public String build(Position position) {
  43         return _build(
  44                 position
  45         );
  46     }
  47
  48     private String _build(Position position) {
  49         StringBuilder sb = new StringBuilder();
  50         sb.append(
  51                 _buildPosition(position)
  52         ).append(
  53                 FEN.FIELDS_SEP
  54         ).append(
  55                 FEN.getColor(
  56                         position.getMove()
  57                 )
  58         ).append(
  59                 FEN.FIELDS_SEP
  60         ).append(
  61                 FEN.getCastle(
  62                         position.getCastle(Color.WHITE),
  63                         position.getCastle(Color.BLACK)
  64                 )
  65         ).append(
  66                 FEN.FIELDS_SEP
  67         ).append(
  68                 FEN.getEnPassant(
  69                         position.getEnPassant()
  70                 )
  71         ).append(
  72                 FEN.FIELDS_SEP
  73         ).append(
  74                 position.getHalfMove()
  75         ).append(
  76                 FEN.FIELDS_SEP
  77         ).append(
  78                 position.getFullMove()
  79         );
  80         return sb.toString();
  81     }
  82
  83     private String _buildPosition(Position position) {
  84         StringBuilder sb = new StringBuilder();
  85         Map<Square, ColorPiece> squares = position.getSquares();
  86         for (int i = Square.getSize() - 1; i >= 0; --i) {
  87             int empty = 0;
  88             for (int j = 0; j < Square.getSize(); ++j) {
  89                 Square square = Square.getSquare(j, i);
  90                 ColorPiece piece = squares.get(square);
  91                 if (piece != null) {
  92                     if (empty > 0)
  93                         sb.append(empty);
  94                     sb.append(
  95                             FEN.getFenPiece(piece)
  96                     );
  97                     empty = 0;
  98                 } else {
  99                     ++empty;
 100                 }
 101             }
 102             if (empty > 0)
 103                 sb.append(empty);
 104             if (i > 0)
 105                 sb.append(FEN.LINE_SEP);
 106         }
 107         return sb.toString();
 108     }
 109
 110     public static Builder getInstance() {
 111         return _instance;
 112     }
 113
 114
 115     public static void main(String[] args) throws ParseException {
 116
 117         Position position = Parsers.FEN.parser().parse(
 118                 "r7/7p/8/8/8/8/PPPPPP2/1N1Q2NR w KQkq a3 1 20"
 119         );
 120         System.out.println(
 121                 getInstance().build(position)
 122         );
 123
 124     }
 125
 126 }