Add Forward + Doubleorda variants

[vchess.git] / client / src / base_rules.js

diff --git a/client/src/base_rules.js b/client/src/base_rules.js
index 53001f6..ee13d5e 100644 (file)
--- a/client/src/base_rules.js
+++ b/client/src/base_rules.js
@@ -80,6 +80,19 @@ export const ChessRules = class ChessRules {
     return V.ShowMoves;
   }
 
+  // Sometimes moves must remain hidden until game ends
+  static get SomeHiddenMoves() {
+    return false;
+  }
+  get someHiddenMoves() {
+    return V.SomeHiddenMoves;
+  }
+
+  // Generally true, unless the variant includes random effects
+  static get CorrConfirm() {
+    return true;
+  }
+
   // Used for Monochrome variant (TODO: harmonize: !canFlip ==> showFirstTurn)
   get showFirstTurn() {
     return false;
@@ -93,11 +106,35 @@ export const ChessRules = class ChessRules {
     return V.CanFlip;
   }
 
+  // For (generally old) variants without checkered board
+  static get Monochrome() {
+    return false;
+  }
+
+  // Some variants require lines drawing
+  static get Lines() {
+    if (V.Monochrome) {
+      let lines = [];
+      // Draw all inter-squares lines
+      for (let i = 0; i <= V.size.x; i++)
+        lines.push([[i, 0], [i, V.size.y]]);
+      for (let j = 0; j <= V.size.y; j++)
+        lines.push([[0, j], [V.size.x, j]]);
+      return lines;
+    }
+    return null;
+  }
+
   // Some variants use click infos:
   doClick() {
     return null;
   }
 
+  // Some variants may need to highlight squares on hover (Hamilton, Weiqi...)
+  hoverHighlight() {
+    return false;
+  }
+
   static get IMAGE_EXTENSION() {
     // All pieces should be in the SVG format
     return ".svg";
@@ -714,8 +751,7 @@ export const ChessRules = class ChessRules {
     if (x2 == lastRank) {
       // promotions arg: special override for Hiddenqueen variant
       if (!!promotions) finalPieces = promotions;
-      else if (!!V.PawnSpecs.promotions)
-        finalPieces = V.PawnSpecs.promotions;
+      else if (!!V.PawnSpecs.promotions) finalPieces = V.PawnSpecs.promotions;
     }
     let tr = null;
     for (let piece of finalPieces) {
@@ -730,6 +766,7 @@ export const ChessRules = class ChessRules {
     const [sizeX, sizeY] = [V.size.x, V.size.y];
     const pawnShiftX = V.PawnSpecs.directions[color];
     const firstRank = (color == "w" ? sizeX - 1 : 0);
+    const forward = (color == 'w' ? -1 : 1);
 
     // Pawn movements in shiftX direction:
     const getPawnMoves = (shiftX) => {
@@ -737,7 +774,7 @@ export const ChessRules = class ChessRules {
       // NOTE: next condition is generally true (no pawn on last rank)
       if (x + shiftX >= 0 && x + shiftX < sizeX) {
         if (this.board[x + shiftX][y] == V.EMPTY) {
-          // One square forward
+          // One square forward (or backward)
           this.addPawnMoves([x, y], [x + shiftX, y], moves, promotions);
           // Next condition because pawns on 1st rank can generally jump
           if (
@@ -748,7 +785,10 @@ export const ChessRules = class ChessRules {
               (color == 'b' && x <= V.PawnSpecs.initShift['b'])
             )
           ) {
-            if (this.board[x + 2 * shiftX][y] == V.EMPTY) {
+            if (
+              shiftX == forward &&
+              this.board[x + 2 * shiftX][y] == V.EMPTY
+            ) {
               // Two squares jump
               moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
               if (
@@ -764,10 +804,7 @@ export const ChessRules = class ChessRules {
         // Captures
         if (V.PawnSpecs.canCapture) {
           for (let shiftY of [-1, 1]) {
-            if (
-              y + shiftY >= 0 &&
-              y + shiftY < sizeY
-            ) {
+            if (y + shiftY >= 0 && y + shiftY < sizeY) {
               if (
                 this.board[x + shiftX][y + shiftY] != V.EMPTY &&
                 this.canTake([x, y], [x + shiftX, y + shiftY])
@@ -778,13 +815,13 @@ export const ChessRules = class ChessRules {
                 );
               }
               if (
-                V.PawnSpecs.captureBackward &&
+                V.PawnSpecs.captureBackward && shiftX == forward &&
                 x - shiftX >= 0 && x - shiftX < V.size.x &&
                 this.board[x - shiftX][y + shiftY] != V.EMPTY &&
                 this.canTake([x, y], [x - shiftX, y + shiftY])
               ) {
                 this.addPawnMoves(
-                  [x, y], [x + shiftX, y + shiftY],
+                  [x, y], [x - shiftX, y + shiftY],
                   moves, promotions
                 );
               }
@@ -884,6 +921,7 @@ export const ChessRules = class ChessRules {
         if (
           // NOTE: "castling" arg is used by some variants (Monster),
           // where "isAttacked" is overloaded in an infinite-recursive way.
+          // TODO: not used anymore (Monster + Doublemove2 are simplified).
           (!castleInCheck && this.isAttacked([x, i], oppCol, "castling")) ||
           (this.board[x][i] != V.EMPTY &&
             // NOTE: next check is enough, because of chessboard constraints
@@ -998,9 +1036,8 @@ export const ChessRules = class ChessRules {
         if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == color) {
           const moves = this.getPotentialMovesFrom([i, j]);
           if (moves.length > 0) {
-            for (let k = 0; k < moves.length; k++) {
+            for (let k = 0; k < moves.length; k++)
               if (this.filterValid([moves[k]]).length > 0) return true;
-            }
           }
         }
       }
@@ -1042,21 +1079,15 @@ export const ChessRules = class ChessRules {
   }
 
   // Is square x,y attacked by 'color' pawns ?
-  isAttackedByPawn([x, y], color) {
+  isAttackedByPawn(sq, color) {
     const pawnShift = (color == "w" ? 1 : -1);
-    if (x + pawnShift >= 0 && x + pawnShift < V.size.x) {
-      for (let i of [-1, 1]) {
-        if (
-          y + i >= 0 &&
-          y + i < V.size.y &&
-          this.getPiece(x + pawnShift, y + i) == V.PAWN &&
-          this.getColor(x + pawnShift, y + i) == color
-        ) {
-          return true;
-        }
-      }
-    }
-    return false;
+    return this.isAttackedBySlideNJump(
+      sq,
+      color,
+      V.PAWN,
+      [[pawnShift, 1], [pawnShift, -1]],
+      "oneStep"
+    );
   }
 
   // Is square x,y attacked by 'color' rooks ?
@@ -1175,10 +1206,8 @@ export const ChessRules = class ChessRules {
       piece = move.appear[0].p;
 
     // Update king position + flags
-    if (piece == V.KING && move.appear.length > 0) {
-      this.kingPos[c][0] = move.appear[0].x;
-      this.kingPos[c][1] = move.appear[0].y;
-    }
+    if (piece == V.KING && move.appear.length > 0)
+      this.kingPos[c] = [move.appear[0].x, move.appear[0].y];
     if (V.HasCastle) this.updateCastleFlags(move, piece);
   }