d0baa6f9966fce4bd79ec5796daceae6a835cbdc
[vchess.git] / client / src / variants / Wildebeest.js
1 class WildebeestRules extends ChessRules
2 {
3 static getPpath(b)
4 {
5 return ([V.CAMEL,V.WILDEBEEST].includes(b[1]) ? "Wildebeest/" : "") + b;
6 }
7
8 static get size() { return {x:10,y:11}; }
9
10 static get CAMEL() { return 'c'; }
11 static get WILDEBEEST() { return 'w'; }
12
13 static get PIECES()
14 {
15 return ChessRules.PIECES.concat([V.CAMEL,V.WILDEBEEST]);
16 }
17
18 static get steps()
19 {
20 return Object.assign(
21 ChessRules.steps, //add camel moves:
22 {'c': [ [-3,-1],[-3,1],[-1,-3],[-1,3],[1,-3],[1,3],[3,-1],[3,1] ]}
23 );
24 }
25
26 static IsGoodEnpassant(enpassant)
27 {
28 if (enpassant != "-")
29 {
30 const squares = enpassant.split(",");
31 if (squares.length > 2)
32 return false;
33 for (let sq of squares)
34 {
35 const ep = V.SquareToCoords(sq);
36 if (isNaN(ep.x) || !V.OnBoard(ep))
37 return false;
38 }
39 }
40 return true;
41 }
42
43 // There may be 2 enPassant squares (if pawn jump 3 squares)
44 getEnpassantFen()
45 {
46 const L = this.epSquares.length;
47 if (!this.epSquares[L-1])
48 return "-"; //no en-passant
49 let res = "";
50 this.epSquares[L-1].forEach(sq => {
51 res += V.CoordsToSquare(sq) + ",";
52 });
53 return res.slice(0,-1); //remove last comma
54 }
55
56 // En-passant after 2-sq or 3-sq jumps
57 getEpSquare(moveOrSquare)
58 {
59 if (!moveOrSquare)
60 return undefined;
61 if (typeof moveOrSquare === "string")
62 {
63 const square = moveOrSquare;
64 if (square == "-")
65 return undefined;
66 let res = [];
67 square.split(",").forEach(sq => {
68 res.push(V.SquareToCoords(sq));
69 });
70 return res;
71 }
72 // Argument is a move:
73 const move = moveOrSquare;
74 const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x];
75 if (this.getPiece(sx,sy) == V.PAWN && Math.abs(sx - ex) >= 2)
76 {
77 const step = (ex-sx) / Math.abs(ex-sx);
78 let res = [{
79 x: sx + step,
80 y: sy
81 }];
82 if (sx + 2*step != ex) //3-squares move
83 {
84 res.push({
85 x: sx + 2*step,
86 y: sy
87 });
88 }
89 return res;
90 }
91 return undefined; //default
92 }
93
94 getPotentialMovesFrom([x,y])
95 {
96 switch (this.getPiece(x,y))
97 {
98 case V.CAMEL:
99 return this.getPotentialCamelMoves([x,y]);
100 case V.WILDEBEEST:
101 return this.getPotentialWildebeestMoves([x,y]);
102 default:
103 return super.getPotentialMovesFrom([x,y])
104 }
105 }
106
107 // Pawns jump 2 or 3 squares, and promote to queen or wildebeest
108 getPotentialPawnMoves([x,y])
109 {
110 const color = this.turn;
111 let moves = [];
112 const [sizeX,sizeY] = [V.size.x,V.size.y];
113 const shiftX = (color == "w" ? -1 : 1);
114 const startRanks = (color == "w" ? [sizeX-2,sizeX-3] : [1,2]);
115 const lastRank = (color == "w" ? 0 : sizeX-1);
116 const finalPieces = x + shiftX == lastRank
117 ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN]
118 : [V.PAWN];
119
120 if (this.board[x+shiftX][y] == V.EMPTY)
121 {
122 // One square forward
123 for (let piece of finalPieces)
124 moves.push(this.getBasicMove([x,y], [x+shiftX,y], {c:color,p:piece}));
125 if (startRanks.includes(x))
126 {
127 if (this.board[x+2*shiftX][y] == V.EMPTY)
128 {
129 // Two squares jump
130 moves.push(this.getBasicMove([x,y], [x+2*shiftX,y]));
131 if (x==startRanks[0] && this.board[x+3*shiftX][y] == V.EMPTY)
132 {
133 // Three squares jump
134 moves.push(this.getBasicMove([x,y], [x+3*shiftX,y]));
135 }
136 }
137 }
138 }
139 // Captures
140 for (let shiftY of [-1,1])
141 {
142 if (y + shiftY >= 0 && y + shiftY < sizeY
143 && this.board[x+shiftX][y+shiftY] != V.EMPTY
144 && this.canTake([x,y], [x+shiftX,y+shiftY]))
145 {
146 for (let piece of finalPieces)
147 {
148 moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY],
149 {c:color,p:piece}));
150 }
151 }
152 }
153
154 // En passant
155 const Lep = this.epSquares.length;
156 const epSquare = this.epSquares[Lep-1];
157 if (!!epSquare)
158 {
159 for (let epsq of epSquare)
160 {
161 // TODO: some redundant checks
162 if (epsq.x == x+shiftX && Math.abs(epsq.y - y) == 1)
163 {
164 var enpassantMove = this.getBasicMove([x,y], [epsq.x,epsq.y]);
165 // WARNING: the captured pawn may be diagonally behind us,
166 // if it's a 3-squares jump and we take on 1st passing square
167 const px = (this.board[x][epsq.y] != V.EMPTY ? x : x - shiftX);
168 enpassantMove.vanish.push({
169 x: px,
170 y: epsq.y,
171 p: 'p',
172 c: this.getColor(px,epsq.y)
173 });
174 moves.push(enpassantMove);
175 }
176 }
177 }
178
179 return moves;
180 }
181
182 // TODO: wildebeest castle
183
184 getPotentialCamelMoves(sq)
185 {
186 return this.getSlideNJumpMoves(sq, V.steps[V.CAMEL], "oneStep");
187 }
188
189 getPotentialWildebeestMoves(sq)
190 {
191 return this.getSlideNJumpMoves(
192 sq, V.steps[V.KNIGHT].concat(V.steps[V.CAMEL]), "oneStep");
193 }
194
195 isAttacked(sq, colors)
196 {
197 return super.isAttacked(sq, colors)
198 || this.isAttackedByCamel(sq, colors)
199 || this.isAttackedByWildebeest(sq, colors);
200 }
201
202 isAttackedByCamel(sq, colors)
203 {
204 return this.isAttackedBySlideNJump(sq, colors,
205 V.CAMEL, V.steps[V.CAMEL], "oneStep");
206 }
207
208 isAttackedByWildebeest(sq, colors)
209 {
210 return this.isAttackedBySlideNJump(sq, colors, V.WILDEBEEST,
211 V.steps[V.KNIGHT].concat(V.steps[V.CAMEL]), "oneStep");
212 }
213
214 checkGameEnd()
215 {
216 // No valid move: game is lost (stalemate is a win)
217 return this.turn == "w" ? "0-1" : "1-0";
218 }
219
220 static get VALUES() {
221 return Object.assign(
222 ChessRules.VALUES,
223 {'c': 3, 'w': 7} //experimental
224 );
225 }
226
227 static get SEARCH_DEPTH() { return 2; }
228
229 static GenRandInitFen()
230 {
231 let pieces = { "w": new Array(10), "b": new Array(10) };
232 for (let c of ["w","b"])
233 {
234 let positions = range(11);
235
236 // Get random squares for bishops + camels (different colors)
237 let randIndexes = sample(range(6), 2).map(i => { return 2*i; });
238 let bishop1Pos = positions[randIndexes[0]];
239 let camel1Pos = positions[randIndexes[1]];
240 // The second bishop (camel) must be on a square of different color
241 let randIndexes_tmp = sample(range(5), 2).map(i => { return 2*i+1; });
242 let bishop2Pos = positions[randIndexes_tmp[0]];
243 let camel2Pos = positions[randIndexes_tmp[1]];
244 for (let idx of randIndexes.concat(randIndexes_tmp)
245 .sort((a,b) => { return b-a; })) //largest indices first
246 {
247 positions.splice(idx, 1);
248 }
249
250 let randIndex = randInt(7);
251 let knight1Pos = positions[randIndex];
252 positions.splice(randIndex, 1);
253 randIndex = randInt(6);
254 let knight2Pos = positions[randIndex];
255 positions.splice(randIndex, 1);
256
257 randIndex = randInt(5);
258 let queenPos = positions[randIndex];
259 positions.splice(randIndex, 1);
260
261 // Random square for wildebeest
262 randIndex = randInt(4);
263 let wildebeestPos = positions[randIndex];
264 positions.splice(randIndex, 1);
265
266 let rook1Pos = positions[0];
267 let kingPos = positions[1];
268 let rook2Pos = positions[2];
269
270 pieces[c][rook1Pos] = 'r';
271 pieces[c][knight1Pos] = 'n';
272 pieces[c][bishop1Pos] = 'b';
273 pieces[c][queenPos] = 'q';
274 pieces[c][camel1Pos] = 'c';
275 pieces[c][camel2Pos] = 'c';
276 pieces[c][wildebeestPos] = 'w';
277 pieces[c][kingPos] = 'k';
278 pieces[c][bishop2Pos] = 'b';
279 pieces[c][knight2Pos] = 'n';
280 pieces[c][rook2Pos] = 'r';
281 }
282 return pieces["b"].join("") +
283 "/ppppppppppp/11/11/11/11/11/11/PPPPPPPPPPP/" +
284 pieces["w"].join("").toUpperCase() +
285 " w 1111 -";
286 }
287 }