Some fixes, work on Eightpieces draft, add a few capturing variants

[vchess.git] / client / src / variants / Racingkings.js

diff --git a/client/src/variants/Racingkings.js b/client/src/variants/Racingkings.js
new file mode 100644 (file)
index 0000000..21d5c85
--- /dev/null
+++ b/client/src/variants/Racingkings.js
@@ -0,0 +1,63 @@
+import { ChessRules } from "@/base_rules";
+
+export const VariantRules = class RacingkingsRules extends ChessRules {
+  static get HasFlags() {
+    return false;
+  }
+
+  static get HasEnpassant() {
+    return false;
+  }
+
+  static get CanFlip() {
+    return false;
+  }
+
+  static GenRandInitFen() {
+    return "8/8/8/8/8/8/krbnNBRK/qrbnNBRQ w 0";
+  }
+
+  filterValid(moves) {
+    if (moves.length == 0) return [];
+    const color = this.turn;
+    const oppCol = V.GetOppCol(color);
+    return moves.filter(m => {
+      this.play(m);
+      // Giving check is forbidden as well:
+      const res = !this.underCheck(color) && !this.underCheck(oppCol);
+      this.undo(m);
+      return res;
+    });
+  }
+
+  getCurrentScore() {
+    // If both kings arrived on the last rank, it's a draw
+    if (this.kingPos['w'][0] == 0 && this.kingPos['b'][0] == 0) return "1/2";
+    // If after my move the opponent king is on last rank, I lose.
+    // This is only possible with black.
+    if (this.turn == 'w' && this.kingPos['w'][0] == 0) return "1-0";
+    // Turn has changed:
+    const color = V.GetOppCol(this.turn);
+    if (this.kingPos[color][0] == 0) {
+      // The opposing edge is reached!
+      // If color is white and the black king can arrive on 8th rank
+      // at next move, then it should be a draw:
+      if (color == "w" && this.kingPos['b'][0] == 1) {
+        // Search for a move
+        const oppKingMoves = this.getPotentialKingMoves(this.kingPos['b']);
+        if (oppKingMoves.some(m => m.end.x == 0)) return "*";
+      }
+      return color == "w" ? "1-0" : "0-1";
+    }
+    if (this.atLeastOneMove()) return "*";
+    // Stalemate (will probably never happen)
+    return "1/2";
+  }
+
+  evalPosition() {
+    // Count material:
+    let evaluation = super.evalPosition();
+    // Ponder with king position:
+    return evaluation/5 + this.kingPos["b"][0] - this.kingPos["w"][0];
+  }
+};