Some fixes, draw lines on board, add 7 variants

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

diff --git a/client/src/variants/Madrasi.js b/client/src/variants/Madrasi.js
new file mode 100644 (file)
index 0000000..54c1862
--- /dev/null
+++ b/client/src/variants/Madrasi.js
@@ -0,0 +1,64 @@
+import { ChessRules } from "@/base_rules";
+
+export class MadrasiRules extends ChessRules {
+  isImmobilized(sq) {
+    const oppCol = V.GetOppCol(this.turn);
+    const piece = this.getPiece(sq[0], sq[1]);
+    let steps = [];
+    switch (piece) {
+      // NOTE: cannot use super.isAttackedByXXX
+      // because it would call the redefined isAttackedBySlideNJump
+      // => Infinite recursive calls.
+      case V.PAWN: {
+        const forward = (oppCol == 'w' ? 1 : -1);
+        steps = [[forward, 1], [forward, -1]];
+        break;
+      }
+      case V.ROOK:
+      case V.BISHOP:
+      case V.KNIGHT:
+        steps = V.steps[piece];
+        break;
+      case V.KING:
+      case V.QUEEN:
+        steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+        break;
+    }
+    return super.isAttackedBySlideNJump(
+      sq, oppCol, piece, steps, [V.KING, V.PAWN, V.KNIGHT].includes(piece))
+  }
+
+  getPotentialMovesFrom([x, y]) {
+    return (
+      !this.isImmobilized([x, y])
+        ? super.getPotentialMovesFrom([x, y])
+        : []
+    );
+  }
+
+  isAttackedBySlideNJump([x, y], color, piece, steps, oneStep) {
+    for (let step of steps) {
+      let rx = x + step[0],
+          ry = y + step[1];
+      while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
+        rx += step[0];
+        ry += step[1];
+      }
+      if (
+        V.OnBoard(rx, ry) &&
+        this.getPiece(rx, ry) == piece &&
+        this.getColor(rx, ry) == color &&
+        // If enemy is immobilized, it doesn't attack:
+        !this.isImmobilized([rx, ry])
+      ) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  isAttackedByKing() {
+    // Connected kings paralyze each other
+    return false;
+  }
+};