Commit | Line | Data |
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0c3fe8a6 | 1 | import { ChessRules } from "@/base_rules"; |
6808d7a1 | 2 | import { ArrayFun } from "@/utils/array"; |
0c3fe8a6 BA |
3 | import { randInt } from "@/utils/alea"; |
4 | ||
6808d7a1 | 5 | export const VariantRules = class DarkRules extends ChessRules { |
20620465 | 6 | // Analyse in Dark mode makes no sense |
8477e53d | 7 | static get CanAnalyze() { |
20620465 BA |
8 | return false; |
9 | } | |
10 | ||
11 | // Moves are revealed only when game ends | |
12 | static get ShowMoves() { | |
13 | return "none"; | |
14 | } | |
15 | ||
6808d7a1 | 16 | setOtherVariables(fen) { |
dac39588 | 17 | super.setOtherVariables(fen); |
6808d7a1 | 18 | const [sizeX, sizeY] = [V.size.x, V.size.y]; |
dac39588 | 19 | this.enlightened = { |
6808d7a1 BA |
20 | w: ArrayFun.init(sizeX, sizeY), |
21 | b: ArrayFun.init(sizeX, sizeY) | |
dac39588 BA |
22 | }; |
23 | // Setup enlightened: squares reachable by each side | |
24 | // (TODO: one side would be enough ?) | |
25 | this.updateEnlightened(); | |
26 | } | |
375ecdd1 | 27 | |
6808d7a1 BA |
28 | updateEnlightened() { |
29 | for (let i = 0; i < V.size.x; i++) { | |
30 | for (let j = 0; j < V.size.y; j++) { | |
dac39588 BA |
31 | this.enlightened["w"][i][j] = false; |
32 | this.enlightened["b"][i][j] = false; | |
33 | } | |
34 | } | |
6808d7a1 | 35 | const pawnShift = { w: -1, b: 1 }; |
dac39588 | 36 | // Initialize with pieces positions (which are seen) |
6808d7a1 BA |
37 | for (let i = 0; i < V.size.x; i++) { |
38 | for (let j = 0; j < V.size.y; j++) { | |
39 | if (this.board[i][j] != V.EMPTY) { | |
40 | const color = this.getColor(i, j); | |
dac39588 BA |
41 | this.enlightened[color][i][j] = true; |
42 | // Add potential squares visible by "impossible pawn capture" | |
6808d7a1 BA |
43 | if (this.getPiece(i, j) == V.PAWN) { |
44 | for (let shiftY of [-1, 1]) { | |
45 | if ( | |
46 | V.OnBoard(i + pawnShift[color], j + shiftY) && | |
47 | this.board[i + pawnShift[color]][j + shiftY] == V.EMPTY | |
48 | ) { | |
241bf8f2 | 49 | this.enlightened[color][i + pawnShift[color]][j + shiftY] = true; |
dac39588 BA |
50 | } |
51 | } | |
52 | } | |
53 | } | |
54 | } | |
55 | } | |
56 | const currentTurn = this.turn; | |
57 | this.turn = "w"; | |
58 | const movesWhite = this.getAllValidMoves(); | |
59 | this.turn = "b"; | |
60 | const movesBlack = this.getAllValidMoves(); | |
61 | this.turn = currentTurn; | |
62 | for (let move of movesWhite) | |
63 | this.enlightened["w"][move.end.x][move.end.y] = true; | |
64 | for (let move of movesBlack) | |
65 | this.enlightened["b"][move.end.x][move.end.y] = true; | |
d048c4c9 BA |
66 | // Include en-passant capturing square if any: |
67 | let moves = currentTurn == "w" ? movesWhite : movesBlack; | |
68 | for (let m of moves) { | |
69 | if ( | |
70 | m.appear[0].p == V.PAWN && | |
71 | m.vanish.length == 2 && | |
72 | m.vanish[1].x != m.end.x | |
73 | ) { | |
74 | const psq = m.vanish[1]; | |
75 | this.enlightened[currentTurn][psq.x][psq.y] = true; | |
76 | break; | |
77 | } | |
78 | } | |
dac39588 | 79 | } |
375ecdd1 | 80 | |
dac39588 | 81 | // Has to be redefined to avoid an infinite loop |
6808d7a1 | 82 | getAllValidMoves() { |
dac39588 | 83 | const color = this.turn; |
dac39588 | 84 | let potentialMoves = []; |
6808d7a1 BA |
85 | for (let i = 0; i < V.size.x; i++) { |
86 | for (let j = 0; j < V.size.y; j++) { | |
87 | if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == color) | |
88 | Array.prototype.push.apply( | |
89 | potentialMoves, | |
90 | this.getPotentialMovesFrom([i, j]) | |
91 | ); | |
dac39588 BA |
92 | } |
93 | } | |
94 | return potentialMoves; //because there are no checks | |
95 | } | |
f6dbe8e3 | 96 | |
6808d7a1 | 97 | getCheckSquares() { |
dac39588 BA |
98 | return []; |
99 | } | |
375ecdd1 | 100 | |
6808d7a1 | 101 | updateVariables(move) { |
dac39588 | 102 | super.updateVariables(move); |
241bf8f2 BA |
103 | if (move.vanish.length >= 2 && move.vanish[1].p == V.KING) |
104 | // We took opponent king (because if castle vanish[1] is a rook) | |
6808d7a1 | 105 | this.kingPos[this.turn] = [-1, -1]; |
388e4c40 | 106 | |
dac39588 BA |
107 | // Update lights for both colors: |
108 | this.updateEnlightened(); | |
109 | } | |
388e4c40 | 110 | |
6808d7a1 | 111 | unupdateVariables(move) { |
dac39588 BA |
112 | super.unupdateVariables(move); |
113 | const c = move.vanish[0].c; | |
114 | const oppCol = V.GetOppCol(c); | |
241bf8f2 BA |
115 | if (this.kingPos[oppCol][0] < 0) |
116 | // Last move took opponent's king: | |
117 | this.kingPos[oppCol] = [move.vanish[1].x, move.vanish[1].y]; | |
388e4c40 | 118 | |
dac39588 BA |
119 | // Update lights for both colors: |
120 | this.updateEnlightened(); | |
121 | } | |
375ecdd1 | 122 | |
6808d7a1 | 123 | getCurrentScore() { |
dac39588 BA |
124 | const color = this.turn; |
125 | const kp = this.kingPos[color]; | |
6808d7a1 | 126 | if (kp[0] < 0) |
241bf8f2 | 127 | // King disappeared |
6808d7a1 | 128 | return color == "w" ? "0-1" : "1-0"; |
241bf8f2 BA |
129 | // Assume that stalemate is impossible (I think so. Would need proof...) |
130 | return "*"; | |
dac39588 | 131 | } |
375ecdd1 | 132 | |
6808d7a1 | 133 | static get THRESHOLD_MATE() { |
dac39588 BA |
134 | return 500; //checkmates evals may be slightly below 1000 |
135 | } | |
5915f720 | 136 | |
dac39588 | 137 | // In this special situation, we just look 1 half move ahead |
6808d7a1 | 138 | getComputerMove() { |
dac39588 BA |
139 | const maxeval = V.INFINITY; |
140 | const color = this.turn; | |
141 | const oppCol = V.GetOppCol(color); | |
6808d7a1 | 142 | const pawnShift = color == "w" ? -1 : 1; |
5915f720 | 143 | |
dac39588 BA |
144 | // Do not cheat: the current enlightment is all we can see |
145 | const myLight = JSON.parse(JSON.stringify(this.enlightened[color])); | |
5915f720 | 146 | |
dac39588 BA |
147 | // Can a slider on (i,j) apparently take my king? |
148 | // NOTE: inaccurate because assume yes if some squares are shadowed | |
6808d7a1 | 149 | const sliderTake = ([i, j], piece) => { |
dac39588 BA |
150 | const kp = this.kingPos[color]; |
151 | let step = undefined; | |
6808d7a1 BA |
152 | if (piece == V.BISHOP) { |
153 | if (Math.abs(kp[0] - i) == Math.abs(kp[1] - j)) { | |
154 | step = [ | |
155 | (i - kp[0]) / Math.abs(i - kp[0]), | |
156 | (j - kp[1]) / Math.abs(j - kp[1]) | |
dac39588 BA |
157 | ]; |
158 | } | |
6808d7a1 BA |
159 | } else if (piece == V.ROOK) { |
160 | if (kp[0] == i) step = [0, (j - kp[1]) / Math.abs(j - kp[1])]; | |
161 | else if (kp[1] == j) step = [(i - kp[0]) / Math.abs(i - kp[0]), 0]; | |
dac39588 | 162 | } |
6808d7a1 | 163 | if (!step) return false; |
dac39588 BA |
164 | // Check for obstacles |
165 | let obstacle = false; | |
166 | for ( | |
6808d7a1 | 167 | let x = kp[0] + step[0], y = kp[1] + step[1]; |
dac39588 | 168 | x != i && y != j; |
6808d7a1 BA |
169 | x += step[0], y += step[1] |
170 | ) { | |
171 | if (myLight[x][y] && this.board[x][y] != V.EMPTY) { | |
dac39588 BA |
172 | obstacle = true; |
173 | break; | |
174 | } | |
175 | } | |
6808d7a1 | 176 | if (!obstacle) return true; |
dac39588 BA |
177 | return false; |
178 | }; | |
5915f720 | 179 | |
dac39588 BA |
180 | // Do I see something which can take my king ? |
181 | const kingThreats = () => { | |
182 | const kp = this.kingPos[color]; | |
6808d7a1 BA |
183 | for (let i = 0; i < V.size.x; i++) { |
184 | for (let j = 0; j < V.size.y; j++) { | |
185 | if ( | |
186 | myLight[i][j] && | |
187 | this.board[i][j] != V.EMPTY && | |
188 | this.getColor(i, j) != color | |
189 | ) { | |
190 | switch (this.getPiece(i, j)) { | |
dac39588 | 191 | case V.PAWN: |
6808d7a1 | 192 | if (kp[0] + pawnShift == i && Math.abs(kp[1] - j) == 1) |
dac39588 BA |
193 | return true; |
194 | break; | |
195 | case V.KNIGHT: | |
6808d7a1 BA |
196 | if ( |
197 | (Math.abs(kp[0] - i) == 2 && Math.abs(kp[1] - j) == 1) || | |
198 | (Math.abs(kp[0] - i) == 1 && Math.abs(kp[1] - j) == 2) | |
199 | ) { | |
dac39588 BA |
200 | return true; |
201 | } | |
202 | break; | |
203 | case V.KING: | |
204 | if (Math.abs(kp[0] - i) == 1 && Math.abs(kp[1] - j) == 1) | |
205 | return true; | |
206 | break; | |
207 | case V.BISHOP: | |
6808d7a1 | 208 | if (sliderTake([i, j], V.BISHOP)) return true; |
dac39588 BA |
209 | break; |
210 | case V.ROOK: | |
6808d7a1 | 211 | if (sliderTake([i, j], V.ROOK)) return true; |
dac39588 BA |
212 | break; |
213 | case V.QUEEN: | |
6808d7a1 | 214 | if (sliderTake([i, j], V.BISHOP) || sliderTake([i, j], V.ROOK)) |
dac39588 BA |
215 | return true; |
216 | break; | |
217 | } | |
218 | } | |
219 | } | |
220 | } | |
221 | return false; | |
222 | }; | |
5915f720 | 223 | |
dac39588 | 224 | let moves = this.getAllValidMoves(); |
6808d7a1 | 225 | for (let move of moves) { |
dac39588 | 226 | this.play(move); |
6808d7a1 | 227 | if (this.kingPos[oppCol][0] >= 0 && kingThreats()) { |
dac39588 BA |
228 | // We didn't take opponent king, and our king will be captured: bad |
229 | move.eval = -maxeval; | |
230 | } | |
231 | this.undo(move); | |
4f518610 | 232 | |
6808d7a1 | 233 | if (move.eval) continue; |
5915f720 | 234 | |
dac39588 | 235 | move.eval = 0; //a priori... |
5915f720 | 236 | |
dac39588 | 237 | // Can I take something ? If yes, do it if it seems good... |
6808d7a1 | 238 | if (move.vanish.length == 2 && move.vanish[1].c != color) { |
71ef1664 | 239 | // OK this isn't a castling move |
dac39588 BA |
240 | const myPieceVal = V.VALUES[move.appear[0].p]; |
241 | const hisPieceVal = V.VALUES[move.vanish[1].p]; | |
71ef1664 BA |
242 | // Favor captures |
243 | if (myPieceVal <= hisPieceVal) move.eval = hisPieceVal - myPieceVal + 1; | |
6808d7a1 | 244 | else { |
dac39588 BA |
245 | // Taking a pawn with minor piece, |
246 | // or minor piece or pawn with a rook, | |
247 | // or anything but a queen with a queen, | |
248 | // or anything with a king. | |
71ef1664 BA |
249 | move.eval = hisPieceVal - myPieceVal; |
250 | //Math.random() < 0.5 ? 1 : -1; | |
dac39588 BA |
251 | } |
252 | } | |
253 | } | |
5915f720 | 254 | |
dac39588 BA |
255 | // TODO: also need to implement the case when an opponent piece (in light) |
256 | // is threatening something - maybe not the king, but e.g. pawn takes rook. | |
5915f720 | 257 | |
6808d7a1 | 258 | moves.sort((a, b) => b.eval - a.eval); |
dac39588 | 259 | let candidates = [0]; |
6808d7a1 | 260 | for (let j = 1; j < moves.length && moves[j].eval == moves[0].eval; j++) |
dac39588 BA |
261 | candidates.push(j); |
262 | return moves[candidates[randInt(candidates.length)]]; | |
263 | } | |
6808d7a1 | 264 | }; |