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 | ||
32f6285e | 5 | export 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 | |
c3d16e78 BA |
81 | filterValid(moves) { |
82 | // Used in the interface | |
83 | return moves; | |
84 | } | |
85 | ||
dac39588 | 86 | // Has to be redefined to avoid an infinite loop |
6808d7a1 | 87 | getAllValidMoves() { |
dac39588 | 88 | const color = this.turn; |
dac39588 | 89 | let potentialMoves = []; |
6808d7a1 BA |
90 | for (let i = 0; i < V.size.x; i++) { |
91 | for (let j = 0; j < V.size.y; j++) { | |
92 | if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == color) | |
93 | Array.prototype.push.apply( | |
94 | potentialMoves, | |
95 | this.getPotentialMovesFrom([i, j]) | |
96 | ); | |
dac39588 BA |
97 | } |
98 | } | |
99 | return potentialMoves; //because there are no checks | |
100 | } | |
f6dbe8e3 | 101 | |
6808d7a1 | 102 | getCheckSquares() { |
dac39588 BA |
103 | return []; |
104 | } | |
375ecdd1 | 105 | |
3a2a7b5f BA |
106 | postPlay(move) { |
107 | super.postPlay(move); | |
241bf8f2 BA |
108 | if (move.vanish.length >= 2 && move.vanish[1].p == V.KING) |
109 | // We took opponent king (because if castle vanish[1] is a rook) | |
6808d7a1 | 110 | this.kingPos[this.turn] = [-1, -1]; |
388e4c40 | 111 | |
dac39588 BA |
112 | // Update lights for both colors: |
113 | this.updateEnlightened(); | |
114 | } | |
388e4c40 | 115 | |
3a2a7b5f BA |
116 | postUndo(move) { |
117 | super.postUndo(move); | |
dac39588 BA |
118 | const c = move.vanish[0].c; |
119 | const oppCol = V.GetOppCol(c); | |
241bf8f2 BA |
120 | if (this.kingPos[oppCol][0] < 0) |
121 | // Last move took opponent's king: | |
122 | this.kingPos[oppCol] = [move.vanish[1].x, move.vanish[1].y]; | |
388e4c40 | 123 | |
dac39588 BA |
124 | // Update lights for both colors: |
125 | this.updateEnlightened(); | |
126 | } | |
375ecdd1 | 127 | |
6808d7a1 | 128 | getCurrentScore() { |
dac39588 BA |
129 | const color = this.turn; |
130 | const kp = this.kingPos[color]; | |
6808d7a1 | 131 | if (kp[0] < 0) |
241bf8f2 | 132 | // King disappeared |
6808d7a1 | 133 | return color == "w" ? "0-1" : "1-0"; |
241bf8f2 BA |
134 | // Assume that stalemate is impossible (I think so. Would need proof...) |
135 | return "*"; | |
dac39588 | 136 | } |
375ecdd1 | 137 | |
6808d7a1 | 138 | static get THRESHOLD_MATE() { |
dac39588 BA |
139 | return 500; //checkmates evals may be slightly below 1000 |
140 | } | |
5915f720 | 141 | |
dac39588 | 142 | // In this special situation, we just look 1 half move ahead |
6808d7a1 | 143 | getComputerMove() { |
dac39588 BA |
144 | const maxeval = V.INFINITY; |
145 | const color = this.turn; | |
146 | const oppCol = V.GetOppCol(color); | |
6808d7a1 | 147 | const pawnShift = color == "w" ? -1 : 1; |
5915f720 | 148 | |
dac39588 BA |
149 | // Do not cheat: the current enlightment is all we can see |
150 | const myLight = JSON.parse(JSON.stringify(this.enlightened[color])); | |
5915f720 | 151 | |
dac39588 BA |
152 | // Can a slider on (i,j) apparently take my king? |
153 | // NOTE: inaccurate because assume yes if some squares are shadowed | |
6808d7a1 | 154 | const sliderTake = ([i, j], piece) => { |
dac39588 BA |
155 | const kp = this.kingPos[color]; |
156 | let step = undefined; | |
6808d7a1 BA |
157 | if (piece == V.BISHOP) { |
158 | if (Math.abs(kp[0] - i) == Math.abs(kp[1] - j)) { | |
159 | step = [ | |
160 | (i - kp[0]) / Math.abs(i - kp[0]), | |
161 | (j - kp[1]) / Math.abs(j - kp[1]) | |
dac39588 BA |
162 | ]; |
163 | } | |
6808d7a1 BA |
164 | } else if (piece == V.ROOK) { |
165 | if (kp[0] == i) step = [0, (j - kp[1]) / Math.abs(j - kp[1])]; | |
166 | else if (kp[1] == j) step = [(i - kp[0]) / Math.abs(i - kp[0]), 0]; | |
dac39588 | 167 | } |
6808d7a1 | 168 | if (!step) return false; |
dac39588 BA |
169 | // Check for obstacles |
170 | let obstacle = false; | |
171 | for ( | |
6808d7a1 | 172 | let x = kp[0] + step[0], y = kp[1] + step[1]; |
dac39588 | 173 | x != i && y != j; |
6808d7a1 BA |
174 | x += step[0], y += step[1] |
175 | ) { | |
176 | if (myLight[x][y] && this.board[x][y] != V.EMPTY) { | |
dac39588 BA |
177 | obstacle = true; |
178 | break; | |
179 | } | |
180 | } | |
6808d7a1 | 181 | if (!obstacle) return true; |
dac39588 BA |
182 | return false; |
183 | }; | |
5915f720 | 184 | |
dac39588 BA |
185 | // Do I see something which can take my king ? |
186 | const kingThreats = () => { | |
187 | const kp = this.kingPos[color]; | |
6808d7a1 BA |
188 | for (let i = 0; i < V.size.x; i++) { |
189 | for (let j = 0; j < V.size.y; j++) { | |
190 | if ( | |
191 | myLight[i][j] && | |
192 | this.board[i][j] != V.EMPTY && | |
193 | this.getColor(i, j) != color | |
194 | ) { | |
195 | switch (this.getPiece(i, j)) { | |
dac39588 | 196 | case V.PAWN: |
6808d7a1 | 197 | if (kp[0] + pawnShift == i && Math.abs(kp[1] - j) == 1) |
dac39588 BA |
198 | return true; |
199 | break; | |
200 | case V.KNIGHT: | |
6808d7a1 BA |
201 | if ( |
202 | (Math.abs(kp[0] - i) == 2 && Math.abs(kp[1] - j) == 1) || | |
203 | (Math.abs(kp[0] - i) == 1 && Math.abs(kp[1] - j) == 2) | |
204 | ) { | |
dac39588 BA |
205 | return true; |
206 | } | |
207 | break; | |
208 | case V.KING: | |
209 | if (Math.abs(kp[0] - i) == 1 && Math.abs(kp[1] - j) == 1) | |
210 | return true; | |
211 | break; | |
212 | case V.BISHOP: | |
6808d7a1 | 213 | if (sliderTake([i, j], V.BISHOP)) return true; |
dac39588 BA |
214 | break; |
215 | case V.ROOK: | |
6808d7a1 | 216 | if (sliderTake([i, j], V.ROOK)) return true; |
dac39588 BA |
217 | break; |
218 | case V.QUEEN: | |
6808d7a1 | 219 | if (sliderTake([i, j], V.BISHOP) || sliderTake([i, j], V.ROOK)) |
dac39588 BA |
220 | return true; |
221 | break; | |
222 | } | |
223 | } | |
224 | } | |
225 | } | |
226 | return false; | |
227 | }; | |
5915f720 | 228 | |
dac39588 | 229 | let moves = this.getAllValidMoves(); |
6808d7a1 | 230 | for (let move of moves) { |
dac39588 | 231 | this.play(move); |
6808d7a1 | 232 | if (this.kingPos[oppCol][0] >= 0 && kingThreats()) { |
dac39588 BA |
233 | // We didn't take opponent king, and our king will be captured: bad |
234 | move.eval = -maxeval; | |
235 | } | |
236 | this.undo(move); | |
4f518610 | 237 | |
6808d7a1 | 238 | if (move.eval) continue; |
5915f720 | 239 | |
dac39588 | 240 | move.eval = 0; //a priori... |
5915f720 | 241 | |
dac39588 | 242 | // Can I take something ? If yes, do it if it seems good... |
6808d7a1 | 243 | if (move.vanish.length == 2 && move.vanish[1].c != color) { |
71ef1664 | 244 | // OK this isn't a castling move |
dac39588 BA |
245 | const myPieceVal = V.VALUES[move.appear[0].p]; |
246 | const hisPieceVal = V.VALUES[move.vanish[1].p]; | |
71ef1664 BA |
247 | // Favor captures |
248 | if (myPieceVal <= hisPieceVal) move.eval = hisPieceVal - myPieceVal + 1; | |
6808d7a1 | 249 | else { |
dac39588 BA |
250 | // Taking a pawn with minor piece, |
251 | // or minor piece or pawn with a rook, | |
252 | // or anything but a queen with a queen, | |
253 | // or anything with a king. | |
71ef1664 BA |
254 | move.eval = hisPieceVal - myPieceVal; |
255 | //Math.random() < 0.5 ? 1 : -1; | |
dac39588 BA |
256 | } |
257 | } | |
258 | } | |
5915f720 | 259 | |
dac39588 BA |
260 | // TODO: also need to implement the case when an opponent piece (in light) |
261 | // is threatening something - maybe not the king, but e.g. pawn takes rook. | |
5915f720 | 262 | |
6808d7a1 | 263 | moves.sort((a, b) => b.eval - a.eval); |
dac39588 | 264 | let candidates = [0]; |
6808d7a1 | 265 | for (let j = 1; j < moves.length && moves[j].eval == moves[0].eval; j++) |
dac39588 BA |
266 | candidates.push(j); |
267 | return moves[candidates[randInt(candidates.length)]]; | |
268 | } | |
6808d7a1 | 269 | }; |