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[vchess.git] / public / javascripts / variants / Checkered.js
index 56fa15a..9de46ff 100644 (file)
@@ -1,10 +1,10 @@
 class CheckeredRules extends ChessRules
 {
-       // Path to pieces
        static getPpath(b)
        {
                return b[0]=='c' ? "Checkered/"+b : b;
        }
+
        static board2fen(b)
        {
                const checkered_codes = {
@@ -18,29 +18,49 @@ class CheckeredRules extends ChessRules
                        return checkered_codes[b[1]];
                return ChessRules.board2fen(b);
        }
+
        static fen2board(f)
        {
+               // Tolerate upper-case versions of checkered pieces (why not?)
                const checkered_pieces = {
                        's': 'p',
+                       'S': 'p',
                        't': 'q',
+                       'T': 'q',
                        'u': 'r',
+                       'U': 'r',
                        'c': 'b',
+                       'C': 'b',
                        'o': 'n',
+                       'O': 'n',
                };
                if (Object.keys(checkered_pieces).includes(f))
                        return 'c'+checkered_pieces[f];
                return ChessRules.fen2board(f);
        }
 
-       setFlags(fen)
+       static get PIECES()
+       {
+               return ChessRules.PIECES.concat(['s','t','u','c','o']);
+       }
+
+       static IsGoodFlags(flags)
        {
-               super.setFlags(fen); //castleFlags
+               // 4 for castle + 16 for pawns
+               return !!flags.match(/^[01]{20,20}$/);
+       }
+
+       setFlags(fenflags)
+       {
+               super.setFlags(fenflags); //castleFlags
                this.pawnFlags =
                {
-                       "w": new Array(8), //pawns can move 2 squares?
-                       "b": new Array(8)
+                       "w": _.map(_.range(8), i => true), //pawns can move 2 squares?
+                       "b": _.map(_.range(8), i => true)
                };
-               const flags = fen.split(" ")[1].substr(4); //skip first 4 digits, for castle
+               if (!fenflags)
+                       return;
+               const flags = fenflags.substr(4); //skip first 4 digits, for castle
                for (let c of ['w','b'])
                {
                        for (let i=0; i<8; i++)
@@ -48,13 +68,12 @@ class CheckeredRules extends ChessRules
                }
        }
 
-       // Aggregates flags into one object
-       get flags() {
+       aggregateFlags()
+       {
                return [this.castleFlags, this.pawnFlags];
        }
 
-       // Reverse operation
-       parseFlags(flags)
+       disaggregateFlags(flags)
        {
                this.castleFlags = flags[0];
                this.pawnFlags = flags[1];
@@ -73,14 +92,19 @@ class CheckeredRules extends ChessRules
        {
                let standardMoves = super.getPotentialMovesFrom([x,y]);
                const lastRank = this.turn == "w" ? 0 : 7;
-               if (this.getPiece(x,y) == VariantRules.KING)
+               if (this.getPiece(x,y) == V.KING)
                        return standardMoves; //king has to be treated differently (for castles)
                let moves = [];
                standardMoves.forEach(m => {
-                       if (m.vanish[0].p == VariantRules.PAWN && Math.abs(m.end.x-m.start.x)==2
-                               && !this.pawnFlags[this.turn][m.start.y])
+                       if (m.vanish[0].p == V.PAWN)
                        {
-                               return; //skip forbidden 2-squares jumps
+                               if (Math.abs(m.end.x-m.start.x)==2 && !this.pawnFlags[this.turn][m.start.y])
+                                       return; //skip forbidden 2-squares jumps
+                               if (this.board[m.end.x][m.end.y] == V.EMPTY && m.vanish.length==2
+                                       && this.getColor(m.start.x,m.start.y) == 'c')
+                               {
+                                       return; //checkered pawns cannot take en-passant
+                               }
                        }
                        if (m.vanish.length == 1)
                                moves.push(m); //no capture
@@ -89,8 +113,8 @@ class CheckeredRules extends ChessRules
                                // A capture occured (m.vanish.length == 2)
                                m.appear[0].c = "c";
                                moves.push(m);
-                               if (m.appear[0].p != m.vanish[1].p //avoid promotions:
-                                       && (m.vanish[0].p != VariantRules.PAWN || m.end.x != lastRank))
+                               if (m.appear[0].p != m.vanish[1].p //avoid promotions (already treated):
+                                       && (m.vanish[0].p != V.PAWN || m.end.x != lastRank))
                                {
                                        // Add transformation into captured piece
                                        let m2 = JSON.parse(JSON.stringify(m));
@@ -104,8 +128,7 @@ class CheckeredRules extends ChessRules
 
        canIplay(side, [x,y])
        {
-               return ((side=='w' && this.moves.length%2==0) || (side=='b' && this.moves.length%2==1))
-                       && [side,'c'].includes(this.getColor(x,y));
+               return (side == this.turn && [side,'c'].includes(this.getColor(x,y)));
        }
 
        // Does m2 un-do m1 ? (to disallow undoing checkered moves)
@@ -128,7 +151,10 @@ class CheckeredRules extends ChessRules
                        const L = this.moves.length;
                        if (L > 0 && this.oppositeMoves(this.moves[L-1], m))
                                return false;
-                       return !this.underCheck(m);
+                       this.play(m);
+                       const res = !this.underCheck(color);
+                       this.undo(m);
+                       return res;
                });
        }
 
@@ -142,7 +168,7 @@ class CheckeredRules extends ChessRules
                        {
                                for (let i of [-1,1])
                                {
-                                       if (y+i>=0 && y+i<8 && this.getPiece(x+pawnShift,y+i)==VariantRules.PAWN
+                                       if (y+i>=0 && y+i<8 && this.getPiece(x+pawnShift,y+i)==V.PAWN
                                                && this.getColor(x+pawnShift,y+i)==c)
                                        {
                                                return true;
@@ -153,67 +179,58 @@ class CheckeredRules extends ChessRules
                return false;
        }
 
-       underCheck(move)
+       underCheck(color)
        {
-               const color = this.turn;
-               this.play(move);
-               let res = this.isAttacked(this.kingPos[color], [this.getOppCol(color),'c']);
-               this.undo(move);
-               return res;
+               return this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c']);
        }
 
-       getCheckSquares(move)
+       getCheckSquares(color)
        {
-               this.play(move);
-               const color = this.turn;
-               this.moves.push(move); //artifically change turn, for checkered pawns (TODO)
-               const kingAttacked = this.isAttacked(this.kingPos[color], [this.getOppCol(color),'c']);
+               // Artifically change turn, for checkered pawns
+               this.turn = V.GetOppCol(color);
+               const kingAttacked = this.isAttacked(
+                       this.kingPos[color], [V.GetOppCol(color),'c']);
                let res = kingAttacked
-                       ? [ JSON.parse(JSON.stringify(this.kingPos[color])) ] //need to duplicate!
-                       : [ ];
-               this.moves.pop();
-               this.undo(move);
+                       ? [JSON.parse(JSON.stringify(this.kingPos[color]))] //need to duplicate!
+                       : [];
+               this.turn = color;
                return res;
        }
 
        updateVariables(move)
        {
-               const c = this.getColor(move.start.x,move.start.y);
-               if (c != 'c') //checkered not concerned by castle flags
-                       super.updateVariables(move);
-
-               // Does it turn off a 2-squares pawn flag?
+               super.updateVariables(move);
+               // Does this move turn off a 2-squares pawn flag?
                const secondRank = [1,6];
-               if (secondRank.includes(move.start.x) && move.vanish[0].p == VariantRules.PAWN)
+               if (secondRank.includes(move.start.x) && move.vanish[0].p == V.PAWN)
                        this.pawnFlags[move.start.x==6 ? "w" : "b"][move.start.y] = false;
        }
 
        checkGameEnd()
        {
                const color = this.turn;
-               if (!this.isAttacked(this.kingPos[color], this.getOppCol(color))
-                       && !this.isAttacked(this.kingPos[color], 'c'))
-               {
-                       return "1/2";
-               }
-               // OK, checkmate
-               return color == "w" ? "0-1" : "1-0";
+               // Artifically change turn, for checkered pawns
+               this.turn = V.GetOppCol(this.turn);
+               const res = this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c'])
+                       ? (color == "w" ? "0-1" : "1-0")
+                       : "1/2";
+               this.turn = V.GetOppCol(this.turn);
+               return res;
        }
 
        evalPosition()
        {
-               const [sizeX,sizeY] = VariantRules.size;
                let evaluation = 0;
                //Just count material for now, considering checkered neutral (...)
-               for (let i=0; i<sizeX; i++)
+               for (let i=0; i<V.size.x; i++)
                {
-                       for (let j=0; j<sizeY; j++)
+                       for (let j=0; j<V.size.y; j++)
                        {
-                               if (this.board[i][j] != VariantRules.EMPTY)
+                               if (this.board[i][j] != V.EMPTY)
                                {
                                        const sqColor = this.getColor(i,j);
                                        const sign = sqColor == "w" ? 1 : (sqColor=="b" ? -1 : 0);
-                                       evaluation += sign * VariantRules.VALUES[this.getPiece(i,j)];
+                                       evaluation += sign * V.VALUES[this.getPiece(i,j)];
                                }
                        }
                }
@@ -222,7 +239,9 @@ class CheckeredRules extends ChessRules
 
        static GenRandInitFen()
        {
-               return ChessRules.GenRandInitFen() + "1111111111111111"; //add 16 pawns flags
+               const randFen = ChessRules.GenRandInitFen();
+               // Add 16 pawns flags:
+               return randFen.replace(" w 1111", " w 11111111111111111111");
        }
 
        getFlagsFen()
@@ -249,24 +268,26 @@ class CheckeredRules extends ChessRules
                }
 
                // Translate final square
-               let finalSquare =
-                       String.fromCharCode(97 + move.end.y) + (VariantRules.size[0]-move.end.x);
+               const finalSquare = V.CoordsToSquare(move.end);
 
-               let piece = this.getPiece(move.start.x, move.start.y);
-               if (piece == VariantRules.PAWN)
+               const piece = this.getPiece(move.start.x, move.start.y);
+               if (piece == V.PAWN)
                {
                        // Pawn move
                        let notation = "";
                        if (move.vanish.length > 1)
                        {
                                // Capture
-                               let startColumn = String.fromCharCode(97 + move.start.y);
-                               notation = startColumn + "x" + finalSquare + "=" + move.appear[0].p.toUpperCase();
+                               const startColumn = V.CoordToColumn(move.start.y);
+                               notation = startColumn + "x" + finalSquare +
+                                       "=" + move.appear[0].p.toUpperCase();
                        }
                        else //no capture
+                       {
                                notation = finalSquare;
-                       if (move.appear.length > 0 && piece != move.appear[0].p) //promotion
-                               notation += "=" + move.appear[0].p.toUpperCase();
+                               if (move.appear.length > 0 && piece != move.appear[0].p) //promotion
+                                       notation += "=" + move.appear[0].p.toUpperCase();
+                       }
                        return notation;
                }