Fix Berolina notation + Marseille PGN
[vchess.git] / public / javascripts / variants / Marseille.js
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1class MarseilleRules extends ChessRules
2{
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3 static IsGoodEnpassant(enpassant)
4 {
5 if (enpassant != "-")
6 {
7 const squares = enpassant.split(",");
8 if (squares.length > 2)
9 return false;
10 for (let sq of squares)
11 {
12 const ep = V.SquareToCoords(sq);
13 if (isNaN(ep.x) || !V.OnBoard(ep))
14 return false;
15 }
16 }
17 return true;
18 }
19
20 getTurnFen()
21 {
22 if (this.startAtFirstMove && this.moves.length==0)
23 return "w";
24 return this.turn + this.subTurn;
25 }
26
27 // There may be 2 enPassant squares (if 2 pawns jump 2 squares in same turn)
28 getEnpassantFen()
29 {
30 const L = this.epSquares.length;
31 if (this.epSquares[L-1].every(epsq => epsq === undefined))
32 return "-"; //no en-passant
33 let res = "";
34 this.epSquares[L-1].forEach(epsq => {
35 if (!!epsq)
36 res += V.CoordsToSquare(epsq) + ",";
37 });
38 return res.slice(0,-1); //remove last comma
39 }
40
41 setOtherVariables(fen)
42 {
43 const parsedFen = V.ParseFen(fen);
44 this.setFlags(parsedFen.flags);
45 if (parsedFen.enpassant == "-")
46 this.epSquares = [ [undefined,undefined] ];
47 else
48 {
49 let res = [];
50 const squares = parsedFen.enpassant.split(",");
51 for (let sq of squares)
52 res.push(V.SquareToCoords(sq));
53 if (res.length == 1)
54 res.push(undefined); //always 2 slots in epSquares[i]
55 this.epSquares = [ res ];
56 }
57 this.scanKingsRooks(fen);
58 // Extract subTurn from turn indicator: "w" (first move), or
59 // "w1" or "w2" white subturn 1 or 2, and same for black
60 const fullTurn = V.ParseFen(fen).turn;
61 this.startAtFirstMove = (fullTurn == "w");
62 this.turn = fullTurn[0];
63 this.subTurn = (fullTurn[1] || 1);
64 }
65
66 getPotentialPawnMoves([x,y])
67 {
68 const color = this.turn;
69 let moves = [];
70 const [sizeX,sizeY] = [V.size.x,V.size.y];
71 const shiftX = (color == "w" ? -1 : 1);
72 const firstRank = (color == 'w' ? sizeX-1 : 0);
73 const startRank = (color == "w" ? sizeX-2 : 1);
74 const lastRank = (color == "w" ? 0 : sizeX-1);
75 const pawnColor = this.getColor(x,y); //can be different for checkered
76
77 if (x+shiftX >= 0 && x+shiftX < sizeX) //TODO: always true
78 {
79 const finalPieces = x + shiftX == lastRank
80 ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN]
81 : [V.PAWN]
82 // One square forward
83 if (this.board[x+shiftX][y] == V.EMPTY)
84 {
85 for (let piece of finalPieces)
86 {
87 moves.push(this.getBasicMove([x,y], [x+shiftX,y],
88 {c:pawnColor,p:piece}));
89 }
90 // Next condition because pawns on 1st rank can generally jump
91 if ([startRank,firstRank].includes(x)
92 && this.board[x+2*shiftX][y] == V.EMPTY)
93 {
94 // Two squares jump
95 moves.push(this.getBasicMove([x,y], [x+2*shiftX,y]));
96 }
97 }
98 // Captures
99 for (let shiftY of [-1,1])
100 {
101 if (y + shiftY >= 0 && y + shiftY < sizeY
102 && this.board[x+shiftX][y+shiftY] != V.EMPTY
103 && this.canTake([x,y], [x+shiftX,y+shiftY]))
104 {
105 for (let piece of finalPieces)
106 {
107 moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY],
108 {c:pawnColor,p:piece}));
109 }
110 }
111 }
112 }
113
114 // En passant: always OK if subturn 1,
115 // OK on subturn 2 only if enPassant was played at subturn 1
116 // (and if there are two e.p. squares available).
117 const Lep = this.epSquares.length;
118 const epSquares = this.epSquares[Lep-1]; //always at least one element
119 let epSqs = [];
120 epSquares.forEach(sq => {
121 if (!!sq)
122 epSqs.push(sq);
123 });
124 if (epSqs.length == 0)
125 return moves;
126 for (let sq of epSqs)
127 {
128 if (this.subTurn == 1 || (epSqs.length == 2 &&
129 // Was this en-passant capture already played at subturn 1 ?
130 this.board[epSqs[0].x][epSqs[0].y] != V.EMPTY))
131 {
132 if (sq.x == x+shiftX && Math.abs(sq.y - y) == 1)
133 {
134 let epMove = this.getBasicMove([x,y], [sq.x,sq.y]);
135 epMove.vanish.push({
136 x: x,
137 y: sq.y,
138 p: 'p',
139 c: this.getColor(x,sq.y)
140 });
141 moves.push(epMove);
142 }
143 }
144 }
145
146 return moves;
147 }
148
149 play(move, ingame)
150 {
6e62b1c7 151 if (!!ingame)
1b61a94d 152 {
6e62b1c7 153 move.notation = [this.getNotation(move), this.getLongNotation(move)];
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154 // In this special case, we also need the "move color":
155 move.color = this.turn;
156 }
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157 move.flags = JSON.stringify(this.aggregateFlags());
158 let lastEpsq = this.epSquares[this.epSquares.length-1];
159 const epSq = this.getEpSquare(move);
160 if (lastEpsq.length == 1)
161 lastEpsq.push(epSq);
162 else
163 {
164 // New turn
165 let newEpsqs = [epSq];
166 if (this.startAtFirstMove && this.moves.length == 0)
167 newEpsqs.push(undefined); //at first move, to force length==2 (TODO)
168 this.epSquares.push(newEpsqs);
169 }
170 V.PlayOnBoard(this.board, move);
171 if (this.startAtFirstMove && this.moves.length == 0)
172 this.turn = "b";
173 // Does this move give check on subturn 1? If yes, skip subturn 2
174 else if (this.subTurn==1 && this.underCheck(this.getOppCol(this.turn)))
175 {
176 this.epSquares[this.epSquares.length-1].push(undefined);
177 this.turn = this.getOppCol(this.turn);
178 move.checkOnSubturn1 = true;
179 }
180 else
181 {
182 if (this.subTurn == 2)
183 this.turn = this.getOppCol(this.turn);
184 this.subTurn = 3 - this.subTurn;
185 }
186 this.moves.push(move);
187 this.updateVariables(move);
188 if (!!ingame)
189 move.hash = hex_md5(this.getFen());
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190 }
191
192 undo(move)
193 {
194 this.disaggregateFlags(JSON.parse(move.flags));
195 let lastEpsq = this.epSquares[this.epSquares.length-1];
196 if (lastEpsq.length == 2)
197 {
198 if (!!move.checkOnSubturn1 ||
199 (this.startAtFirstMove && this.moves.length == 1))
200 {
201 this.epSquares.pop(); //remove real + artificial e.p. squares
202 }
203 else
204 lastEpsq.pop();
205 }
206 else
207 this.epSquares.pop();
208 V.UndoOnBoard(this.board, move);
209 if (this.startAtFirstMove && this.moves.length == 1)
210 this.turn = "w";
211 else if (move.checkOnSubturn1)
212 {
213 this.turn = this.getOppCol(this.turn);
214 this.subTurn = 1;
215 }
216 else
217 {
218 if (this.subTurn == 1)
219 this.turn = this.getOppCol(this.turn);
220 this.subTurn = 3 - this.subTurn;
221 }
222 this.moves.pop();
223 this.unupdateVariables(move);
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224 }
225
226 // NOTE: GenRandInitFen() is OK,
227 // since at first move turn indicator is just "w"
228
229 // No alpha-beta here, just adapted min-max at depth 2(+1)
230 getComputerMove()
231 {
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232 if (this.subTurn == 2)
233 return null; //TODO: imperfect interface setup
234
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235 const maxeval = V.INFINITY;
236 const color = this.turn;
237 const oppCol = this.getOppCol(this.turn);
238
239 // Search best (half) move for opponent turn
240 const getBestMoveEval = () => {
241 let moves = this.getAllValidMoves();
242 if (moves.length == 0)
243 {
244 const score = this.checkGameEnd();
245 if (score == "1/2")
246 return 0;
247 return maxeval * (score == "1-0" ? 1 : -1);
248 }
249 let res = (oppCol == "w" ? -maxeval : maxeval);
250 for (let m of moves)
251 {
252 this.play(m);
253 this.turn = color; //very artificial...
254 if (!this.atLeastOneMove())
255 {
256 const score = this.checkGameEnd();
257 if (score == "1/2")
258 res = (oppCol == "w" ? Math.max(res, 0) : Math.min(res, 0));
259 else
260 {
261 // Found a mate
262 this.turn = oppCol;
263 this.undo(m);
264 return maxeval * (score == "1-0" ? 1 : -1);
265 }
266 }
267 const evalPos = this.evalPosition();
268 res = (oppCol == "w" ? Math.max(res, evalPos) : Math.min(res, evalPos));
269 this.turn = oppCol;
270 this.undo(m);
271 }
272 return res;
273 };
274
275 let moves11 = this.getAllValidMoves();
276 let doubleMoves = [];
277 // Rank moves using a min-max at depth 2
278 for (let i=0; i<moves11.length; i++)
279 {
280 moves11[i].eval = (color=="w" ? -1 : 1) * maxeval;
281 this.play(moves11[i]);
282 if (this.turn != color)
283 {
284 // We gave check with last move: search the best opponent move
285 doubleMoves.push({moves:[moves11[i]], eval:getBestMoveEval()});
286 }
287 else
288 {
289 let moves12 = this.getAllValidMoves();
290 for (let j=0; j<moves12.length; j++)
291 {
292 this.play(moves12[j]);
293 doubleMoves.push({
294 moves:[moves11[i],moves12[j]],
295 eval:getBestMoveEval()});
296 this.undo(moves12[j]);
297 }
298 }
299 this.undo(moves11[i]);
300 }
301
302 doubleMoves.sort( (a,b) => {
303 return (color=="w" ? 1 : -1) * (b.eval - a.eval); });
304 let candidates = [0]; //indices of candidates moves
305 for (let i=1;
306 i<doubleMoves.length && doubleMoves[i].eval == doubleMoves[0].eval;
307 i++)
308 {
309 candidates.push(i);
310 }
78bab51e 311
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312 const selected = doubleMoves[_.sample(candidates, 1)].moves;
313 if (selected.length == 1)
314 return selected[0];
315 return selected;
316 }
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317
318 getPGN(mycolor, score, fenStart, mode)
319 {
320 let pgn = "";
321 pgn += '[Site "vchess.club"]<br>';
322 const opponent = mode=="human" ? "Anonymous" : "Computer";
323 pgn += '[Variant "' + variant + '"]<br>';
324 pgn += '[Date "' + getDate(new Date()) + '"]<br>';
325 pgn += '[White "' + (mycolor=='w'?'Myself':opponent) + '"]<br>';
326 pgn += '[Black "' + (mycolor=='b'?'Myself':opponent) + '"]<br>';
327 pgn += '[FenStart "' + fenStart + '"]<br>';
328 pgn += '[Fen "' + this.getFen() + '"]<br>';
329 pgn += '[Result "' + score + '"]<br><br>';
330
331 let counter = 1;
332 let i = 0;
333 while (i < this.moves.length)
334 {
335 pgn += (counter++) + ".";
336 for (let color of ["w","b"])
337 {
338 let move = "";
339 while (i < this.moves.length && this.moves[i].color == color)
340 move += this.moves[i++].notation[0] + ",";
341 move = move.slice(0,-1); //remove last comma
342 pgn += move + (i < this.moves.length-1 ? " " : "");
343 }
344 }
345 pgn += "<br><br>";
346
347 // "Complete moves" PGN (helping in ambiguous cases)
348 counter = 1;
349 i = 0;
350 while (i < this.moves.length)
351 {
352 pgn += (counter++) + ".";
353 for (let color of ["w","b"])
354 {
355 let move = "";
356 while (i < this.moves.length && this.moves[i].color == color)
357 move += this.moves[i++].notation[1] + ",";
358 move = move.slice(0,-1); //remove last comma
359 pgn += move + (i < this.moves.length-1 ? " " : "");
360 }
361 }
362
363 return pgn;
364 }
365
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366}
367
368const VariantRules = MarseilleRules;