Draft Hiddenqueen, Grasshopper and Knightmate chess (rules unwritten)
[vchess.git] / client / src / variants / Antiking.js
1 import { ChessRules } from "@/base_rules";
2 import { ArrayFun } from "@/utils/array";
3 import { randInt } from "@/utils/alea";
4
5 export const VariantRules = class AntikingRules extends ChessRules {
6 static get ANTIKING() {
7 return "a";
8 }
9
10 static get PIECES() {
11 return ChessRules.PIECES.concat([V.ANTIKING]);
12 }
13
14 getPpath(b) {
15 return b[1] == "a" ? "Antiking/" + b : b;
16 }
17
18 setOtherVariables(fen) {
19 super.setOtherVariables(fen);
20 this.antikingPos = { w: [-1, -1], b: [-1, -1] };
21 const rows = V.ParseFen(fen).position.split("/");
22 for (let i = 0; i < rows.length; i++) {
23 let k = 0;
24 for (let j = 0; j < rows[i].length; j++) {
25 switch (rows[i].charAt(j)) {
26 case "a":
27 this.antikingPos["b"] = [i, k];
28 break;
29 case "A":
30 this.antikingPos["w"] = [i, k];
31 break;
32 default: {
33 const num = parseInt(rows[i].charAt(j));
34 if (!isNaN(num)) k += num - 1;
35 }
36 }
37 k++;
38 }
39 }
40 }
41
42 canTake([x1, y1], [x2, y2]) {
43 const piece1 = this.getPiece(x1, y1);
44 const piece2 = this.getPiece(x2, y2);
45 const color1 = this.getColor(x1, y1);
46 const color2 = this.getColor(x2, y2);
47 return (
48 piece2 != "a" &&
49 ((piece1 != "a" && color1 != color2) ||
50 (piece1 == "a" && color1 == color2))
51 );
52 }
53
54 getPotentialMovesFrom([x, y]) {
55 switch (this.getPiece(x, y)) {
56 case V.ANTIKING:
57 return this.getPotentialAntikingMoves([x, y]);
58 default:
59 return super.getPotentialMovesFrom([x, y]);
60 }
61 }
62
63 getPotentialAntikingMoves(sq) {
64 return this.getSlideNJumpMoves(
65 sq,
66 V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
67 "oneStep"
68 );
69 }
70
71 isAttacked(sq, colors) {
72 return (
73 super.isAttacked(sq, colors) || this.isAttackedByAntiking(sq, colors)
74 );
75 }
76
77 isAttackedByKing([x, y], colors) {
78 if (this.getPiece(x, y) == V.ANTIKING) return false; //antiking is not attacked by king
79 return this.isAttackedBySlideNJump(
80 [x, y],
81 colors,
82 V.KING,
83 V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
84 "oneStep"
85 );
86 }
87
88 isAttackedByAntiking([x, y], colors) {
89 if ([V.KING, V.ANTIKING].includes(this.getPiece(x, y))) return false; //(anti)king is not attacked by antiking
90 return this.isAttackedBySlideNJump(
91 [x, y],
92 colors,
93 V.ANTIKING,
94 V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
95 "oneStep"
96 );
97 }
98
99 underCheck(color) {
100 const oppCol = V.GetOppCol(color);
101 let res =
102 this.isAttacked(this.kingPos[color], [oppCol]) ||
103 !this.isAttacked(this.antikingPos[color], [oppCol]);
104 return res;
105 }
106
107 getCheckSquares(color) {
108 let res = super.getCheckSquares(color);
109 if (!this.isAttacked(this.antikingPos[color], [V.GetOppCol(color)]))
110 res.push(JSON.parse(JSON.stringify(this.antikingPos[color])));
111 return res;
112 }
113
114 updateVariables(move) {
115 super.updateVariables(move);
116 const piece = move.vanish[0].p;
117 const c = move.vanish[0].c;
118 // Update antiking position
119 if (piece == V.ANTIKING) {
120 this.antikingPos[c][0] = move.appear[0].x;
121 this.antikingPos[c][1] = move.appear[0].y;
122 }
123 }
124
125 unupdateVariables(move) {
126 super.unupdateVariables(move);
127 const c = move.vanish[0].c;
128 if (move.vanish[0].p == V.ANTIKING)
129 this.antikingPos[c] = [move.start.x, move.start.y];
130 }
131
132 getCurrentScore() {
133 if (this.atLeastOneMove())
134 return "*";
135
136 const color = this.turn;
137 const oppCol = V.GetOppCol(color);
138 if (
139 !this.isAttacked(this.kingPos[color], [oppCol]) &&
140 this.isAttacked(this.antikingPos[color], [oppCol])
141 ) {
142 return "1/2";
143 }
144 return color == "w" ? "0-1" : "1-0";
145 }
146
147 static get VALUES() {
148 return Object.assign(
149 { a: 1000 },
150 ChessRules.VALUES
151 );
152 }
153
154 static GenRandInitFen() {
155 let pieces = { w: new Array(8), b: new Array(8) };
156 let antikingPos = { w: -1, b: -1 };
157 for (let c of ["w", "b"]) {
158 let positions = ArrayFun.range(8);
159
160 // Get random squares for bishops, but avoid corners; because,
161 // if an antiking blocks a cornered bishop, it can never be checkmated
162 let randIndex = 2 * randInt(1, 4);
163 const bishop1Pos = positions[randIndex];
164 let randIndex_tmp = 2 * randInt(3) + 1;
165 const bishop2Pos = positions[randIndex_tmp];
166 positions.splice(Math.max(randIndex, randIndex_tmp), 1);
167 positions.splice(Math.min(randIndex, randIndex_tmp), 1);
168
169 randIndex = randInt(6);
170 const knight1Pos = positions[randIndex];
171 positions.splice(randIndex, 1);
172 randIndex = randInt(5);
173 const knight2Pos = positions[randIndex];
174 positions.splice(randIndex, 1);
175
176 randIndex = randInt(4);
177 const queenPos = positions[randIndex];
178 positions.splice(randIndex, 1);
179
180 const rook1Pos = positions[0];
181 const kingPos = positions[1];
182 const rook2Pos = positions[2];
183
184 // Random squares for antikings
185 antikingPos[c] = randInt(8);
186
187 pieces[c][rook1Pos] = "r";
188 pieces[c][knight1Pos] = "n";
189 pieces[c][bishop1Pos] = "b";
190 pieces[c][queenPos] = "q";
191 pieces[c][kingPos] = "k";
192 pieces[c][bishop2Pos] = "b";
193 pieces[c][knight2Pos] = "n";
194 pieces[c][rook2Pos] = "r";
195 }
196 const ranks23_black =
197 "pppppppp/" +
198 (antikingPos["w"] > 0 ? antikingPos["w"] : "") +
199 "A" +
200 (antikingPos["w"] < 7 ? 7 - antikingPos["w"] : "");
201 const ranks23_white =
202 (antikingPos["b"] > 0 ? antikingPos["b"] : "") +
203 "a" +
204 (antikingPos["b"] < 7 ? 7 - antikingPos["b"] : "") +
205 "/PPPPPPPP";
206 return (
207 pieces["b"].join("") +
208 "/" +
209 ranks23_black +
210 "/8/8/" +
211 ranks23_white +
212 "/" +
213 pieces["w"].join("").toUpperCase() +
214 " w 0 1111 -"
215 );
216 }
217 };