Add Relayup

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

diff --git a/client/src/variants/Relayup.js b/client/src/variants/Relayup.js
index 4b85fde..446c927 100644 (file)
--- a/client/src/variants/Relayup.js
+++ b/client/src/variants/Relayup.js
@@ -1,6 +1,6 @@
 import { ChessRules } from "@/base_rules";
 
-// Pawns relayed by one square at a time (but with relaying pioece movements)
+// Pawns relayed by one square at a time (but with relaying piece movements)
 // diff from https://www.chessvariants.com/rules/relay-chess ==> new name
 export class RelayupRules extends ChessRules {
 
@@ -22,13 +22,69 @@ export class RelayupRules extends ChessRules {
 
   getPotentialMovesFrom([x, y]) {
     let moves = super.getPotentialMovesFrom([x, y]);
+    // Expand potential moves if guarded by friendly pieces.
+    // NOTE: pawns cannot be promoted through a relaying move
+    const piece = this.getPiece(x,y);
+    const color = this.turn;
+    const lastRank = (color == 'w' ? 0 : 7);
+    const sq = [x, y];
+    const oneStep = (piece == V.PAWN);
+    let guardedBy = {};
+    if (piece != V.ROOK && super.isAttackedByRook(sq, color))
+      guardedBy[V.ROOK] = true;
+    if (piece != V.KNIGHT && super.isAttackedByKnight(sq, color))
+      guardedBy[V.KNIGHT] = true;
+    if (piece != V.BISHOP && super.isAttackedByBishop(sq, color))
+      guardedBy[V.BISHOP] = true;
+    if (piece != V.QUEEN && super.isAttackedByQueen(sq, color))
+      guardedBy[V.QUEEN] = true;
+    if (piece != V.KING && super.isAttackedByKing(sq, color))
+      guardedBy[V.KING] = true;
+    Object.keys(guardedBy).forEach(pg => {
+      let steps = null;
+      if ([V.ROOK, V.KNIGHT, V.BISHOP].includes(pg)) steps = V.steps[pg];
+      else steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+      const extraMoves =
+        super.getSlideNJumpMoves(
+          sq, steps, oneStep || [V.KNIGHT, V.KING].includes(pg))
+        .filter(m => {
+          return (
+            (piece != V.PAWN || m.end.x != lastRank) &&
+            (moves.every(mv => mv.end.x != m.end.x || mv.end.y != m.end.y))
+          );
+        });
+      moves = moves.concat(extraMoves);
+    });
+    return moves;
+  }
 
-    // Expand possible moves if guarded by friendly pieces:
-    // --> Pawns cannot be promoted through a relaying move (thus 8th rank forbidden)
-    // TODO
-
+  filterValid(moves) {
     return moves;
   }
+  getCheckSquares() {
+    return [];
+  }
+
+  postPlay(move) {
+    super.postPlay(move);
+    if (move.vanish.length == 2 && move.vanish[1].p == V.KING)
+      this.kingPos[move.vanish[1].c] = [-1, -1];
+  }
+
+  postUndo(move) {
+    super.postUndo(move);
+    if (move.vanish.length == 2 && move.vanish[1].p == V.KING) {
+      const v = move.vanish[1];
+      this.kingPos[v.c] = [v.x, v.y];
+    }
+  }
+
+  getCurrentScore() {
+    const c = this.turn;
+    if (this.kingPos[c][0] < 0) return (c == 'w' ? "0-1" : "1-0");
+    // It seems that there is always a possible move (TODO: check this)
+    return "*";
+  }
 
   getNotation(move) {
     // Translate final and initial square