Improve(?) Monochrome + simplify Zen variant

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

diff --git a/client/src/variants/Zen.js b/client/src/variants/Zen.js
index 56e7108..808d543 100644 (file)
--- a/client/src/variants/Zen.js
+++ b/client/src/variants/Zen.js
@@ -1,9 +1,29 @@
 import { ChessRules } from "@/base_rules";
 
 export class ZenRules extends ChessRules {
-  // NOTE: enPassant, if enabled, would need to redefine carefully getEpSquare
-  static get HasEnpassant() {
-    return false;
+  getEpSquare(moveOrSquare) {
+    if (!moveOrSquare) return undefined;
+    if (typeof moveOrSquare === "string") {
+      const square = moveOrSquare;
+      if (square == "-") return undefined;
+      return V.SquareToCoords(square);
+    }
+    const move = moveOrSquare;
+    const s = move.start,
+          e = move.end;
+    if (
+      // Exclude captures (of rooks for example)
+      move.vanish.length == 1 &&
+      s.y == e.y &&
+      Math.abs(s.x - e.x) == 2 &&
+      move.appear[0].p == V.PAWN
+    ) {
+      return {
+        x: (s.x + e.x) / 2,
+        y: s.y
+      };
+    }
+    return undefined;
   }
 
   // TODO(?): some duplicated code in 2 next functions
@@ -46,6 +66,7 @@ export class ZenRules extends ChessRules {
     const oneStep = [V.KNIGHT,V.PAWN].includes(asA); //we don't capture king
     const lastRank = color == "w" ? 0 : V.size.x - 1;
     const promotionPieces = [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN];
+    const oppCol = V.GetOppCol(color);
     outerLoop: for (let loop = 0; loop < steps.length; loop++) {
       const step = steps[loop];
       let i = x + step[0];
@@ -57,7 +78,7 @@ export class ZenRules extends ChessRules {
       }
       if (
         V.OnBoard(i, j) &&
-        this.getColor(i, j) == V.GetOppCol(color) &&
+        this.getColor(i, j) == oppCol &&
         this.getPiece(i, j) == asA
       ) {
         // eat!
@@ -78,13 +99,11 @@ export class ZenRules extends ChessRules {
   // Find possible captures from a square: look in every direction!
   findCaptures(sq) {
     let moves = [];
-
     Array.prototype.push.apply(moves, this.findCaptures_aux(sq, V.PAWN));
     Array.prototype.push.apply(moves, this.findCaptures_aux(sq, V.ROOK));
     Array.prototype.push.apply(moves, this.findCaptures_aux(sq, V.KNIGHT));
     Array.prototype.push.apply(moves, this.findCaptures_aux(sq, V.BISHOP));
     Array.prototype.push.apply(moves, this.findCaptures_aux(sq, V.QUEEN));
-
     return moves;
   }
 
@@ -92,49 +111,8 @@ export class ZenRules extends ChessRules {
     return false; //captures handled separately
   }
 
-  getPotentialPawnMoves([x, y]) {
-    let moves = super.getPotentialPawnMoves([x, y]);
-    // Add "zen" captures
-    Array.prototype.push.apply(moves, this.findCaptures([x, y]));
-    return moves;
-  }
-
-  getPotentialRookMoves(sq) {
-    let noCaptures = this.getSlideNJumpMoves(sq, V.steps[V.ROOK]);
-    let captures = this.findCaptures(sq);
-    return noCaptures.concat(captures);
-  }
-
-  getPotentialKnightMoves(sq) {
-    let noCaptures = this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep");
-    let captures = this.findCaptures(sq);
-    return noCaptures.concat(captures);
-  }
-
-  getPotentialBishopMoves(sq) {
-    let noCaptures = this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]);
-    let captures = this.findCaptures(sq);
-    return noCaptures.concat(captures);
-  }
-
-  getPotentialQueenMoves(sq) {
-    let noCaptures = this.getSlideNJumpMoves(
-      sq,
-      V.steps[V.ROOK].concat(V.steps[V.BISHOP])
-    );
-    let captures = this.findCaptures(sq);
-    return noCaptures.concat(captures);
-  }
-
-  getPotentialKingMoves(sq) {
-    // Initialize with normal moves
-    let noCaptures = this.getSlideNJumpMoves(
-      sq,
-      V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
-      "oneStep"
-    );
-    let captures = this.findCaptures(sq);
-    return noCaptures.concat(captures).concat(this.getCastleMoves(sq));
+  getPotentialMovesFrom(sq) {
+    return super.getPotentialMovesFrom(sq).concat(this.findCaptures(sq));
   }
 
   getNotation(move) {
@@ -145,7 +123,7 @@ export class ZenRules extends ChessRules {
       return "0-0";
     }
 
-    // Translate initial square (because pieces may fly unusually in this variant!)
+    // Translate initial square (because pieces may fly unusually!)
     const initialSquare = V.CoordsToSquare(move.start);
 
     // Translate final square
@@ -155,15 +133,16 @@ export class ZenRules extends ChessRules {
     const piece = this.getPiece(move.start.x, move.start.y);
     if (piece == V.PAWN) {
       // pawn move (TODO: enPassant indication)
-      if (move.vanish.length > 1) {
+      if (move.vanish.length == 2) {
         // capture
         notation = initialSquare + "x" + finalSquare;
-      } //no capture
+      }
       else notation = finalSquare;
       if (piece != move.appear[0].p)
         //promotion
         notation += "=" + move.appear[0].p.toUpperCase();
-    } else {
+    }
+    else {
       // Piece movement
       notation = piece.toUpperCase();
       if (move.vanish.length > 1) notation += initialSquare + "x";