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[vchess.git] / public / javascripts / variants / Marseille.js
index 02daa22..7d83bd5 100644 (file)
@@ -19,8 +19,6 @@ class MarseilleRules extends ChessRules
 
        getTurnFen()
        {
-               if (this.startAtFirstMove && this.moves.length==0)
-                       return "w";
                return this.turn + this.subTurn;
        }
 
@@ -43,24 +41,21 @@ class MarseilleRules extends ChessRules
                const parsedFen = V.ParseFen(fen);
                this.setFlags(parsedFen.flags);
                if (parsedFen.enpassant == "-")
-                       this.epSquares = [ [undefined,undefined] ];
+                       this.epSquares = [ [undefined] ];
                else
                {
                        let res = [];
                        const squares = parsedFen.enpassant.split(",");
                        for (let sq of squares)
                                res.push(V.SquareToCoords(sq));
-                       if (res.length == 1)
-                               res.push(undefined); //always 2 slots in epSquares[i]
                        this.epSquares = [ res ];
                }
                this.scanKingsRooks(fen);
                // Extract subTurn from turn indicator: "w" (first move), or
                // "w1" or "w2" white subturn 1 or 2, and same for black
                const fullTurn = V.ParseFen(fen).turn;
-               this.startAtFirstMove = (fullTurn == "w");
                this.turn = fullTurn[0];
-               this.subTurn = (fullTurn[1] || 1);
+               this.subTurn = (fullTurn[1] || 0); //"w0" = special code for first move in game
        }
 
        getPotentialPawnMoves([x,y])
@@ -72,41 +67,37 @@ class MarseilleRules extends ChessRules
                const firstRank = (color == 'w' ? sizeX-1 : 0);
                const startRank = (color == "w" ? sizeX-2 : 1);
                const lastRank = (color == "w" ? 0 : sizeX-1);
-               const pawnColor = this.getColor(x,y); //can be different for checkered
+               const finalPieces = x + shiftX == lastRank
+                       ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN]
+                       : [V.PAWN];
 
-               if (x+shiftX >= 0 && x+shiftX < sizeX) //TODO: always true
+               // One square forward
+               if (this.board[x+shiftX][y] == V.EMPTY)
                {
-                       const finalPieces = x + shiftX == lastRank
-                               ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN]
-                               : [V.PAWN]
-                       // One square forward
-                       if (this.board[x+shiftX][y] == V.EMPTY)
+                       for (let piece of finalPieces)
                        {
-                               for (let piece of finalPieces)
-                               {
-                                       moves.push(this.getBasicMove([x,y], [x+shiftX,y],
-                                               {c:pawnColor,p:piece}));
-                               }
-                               // Next condition because pawns on 1st rank can generally jump
-                               if ([startRank,firstRank].includes(x)
-                                       && this.board[x+2*shiftX][y] == V.EMPTY)
-                               {
-                                       // Two squares jump
-                                       moves.push(this.getBasicMove([x,y], [x+2*shiftX,y]));
-                               }
+                               moves.push(this.getBasicMove([x,y], [x+shiftX,y],
+                                       {c:color,p:piece}));
                        }
-                       // Captures
-                       for (let shiftY of [-1,1])
+                       // Next condition because pawns on 1st rank can generally jump
+                       if ([startRank,firstRank].includes(x)
+                               && this.board[x+2*shiftX][y] == V.EMPTY)
                        {
-                               if (y + shiftY >= 0 && y + shiftY < sizeY
-                                       && this.board[x+shiftX][y+shiftY] != V.EMPTY
-                                       && this.canTake([x,y], [x+shiftX,y+shiftY]))
+                               // Two squares jump
+                               moves.push(this.getBasicMove([x,y], [x+2*shiftX,y]));
+                       }
+               }
+               // Captures
+               for (let shiftY of [-1,1])
+               {
+                       if (y + shiftY >= 0 && y + shiftY < sizeY
+                               && this.board[x+shiftX][y+shiftY] != V.EMPTY
+                               && this.canTake([x,y], [x+shiftX,y+shiftY]))
+                       {
+                               for (let piece of finalPieces)
                                {
-                                       for (let piece of finalPieces)
-                                       {
-                                               moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY],
-                                                       {c:pawnColor,p:piece}));
-                                       }
+                                       moves.push(this.getBasicMove([x,y], [x+shiftX,y+shiftY],
+                                               {c:color,p:piece}));
                                }
                        }
                }
@@ -123,20 +114,24 @@ class MarseilleRules extends ChessRules
                });
                if (epSqs.length == 0)
                        return moves;
+               const oppCol = V.GetOppCol(color);
                for (let sq of epSqs)
                {
                        if (this.subTurn == 1 || (epSqs.length == 2 &&
                                // Was this en-passant capture already played at subturn 1 ?
+                               // (Or maybe the opponent filled the en-passant square with a piece)
                                this.board[epSqs[0].x][epSqs[0].y] != V.EMPTY))
                        {
-                               if (sq.x == x+shiftX && Math.abs(sq.y - y) == 1)
+                               if (sq.x == x+shiftX && Math.abs(sq.y - y) == 1
+                                       // Add condition "enemy pawn must be present"
+                                       && this.getPiece(x,sq.y) == V.PAWN && this.getColor(x,sq.y) == oppCol)
                                {
                                        let epMove = this.getBasicMove([x,y], [sq.x,sq.y]);
                                        epMove.vanish.push({
                                                x: x,
                                                y: sq.y,
                                                p: 'p',
-                                               c: this.getColor(x,sq.y)
+                                               c: oppCol
                                        });
                                        moves.push(epMove);
                                }
@@ -146,87 +141,70 @@ class MarseilleRules extends ChessRules
                return moves;
        }
 
-       play(move, ingame)
+       play(move)
        {
-//             console.log("play " + this.getNotation(move));
-//             console.log(this.turn + " "+ this.subTurn);
-               if (!!ingame)
-                       move.notation = [this.getNotation(move), this.getLongNotation(move)];
                move.flags = JSON.stringify(this.aggregateFlags());
-               let lastEpsq = this.epSquares[this.epSquares.length-1];
+               move.turn = this.turn + this.subturn;
+               V.PlayOnBoard(this.board, move);
                const epSq = this.getEpSquare(move);
-               if (lastEpsq.length == 1)
-                       lastEpsq.push(epSq);
-               else
+               if (this.subTurn == 0) //first move in game
                {
-                       // New turn
-                       let newEpsqs = [epSq];
-                       if (this.startAtFirstMove && this.moves.length == 0)
-                               newEpsqs.push(undefined); //at first move, to force length==2 (TODO)
-                       this.epSquares.push(newEpsqs);
-               }
-               V.PlayOnBoard(this.board, move);
-               if (this.startAtFirstMove && this.moves.length == 0)
                        this.turn = "b";
+                       this.epSquares.push([epSq]);
+               }
                // Does this move give check on subturn 1? If yes, skip subturn 2
-               else if (this.subTurn==1 && this.underCheck(this.getOppCol(this.turn)))
+               else if (this.subTurn==1 && this.underCheck(V.GetOppCol(this.turn)))
                {
-                       this.epSquares[this.epSquares.length-1].push(undefined);
-                       this.turn = this.getOppCol(this.turn);
+                       this.turn = V.GetOppCol(this.turn);
+                       this.epSquares.push([epSq]);
                        move.checkOnSubturn1 = true;
                }
                else
                {
                        if (this.subTurn == 2)
-                               this.turn = this.getOppCol(this.turn);
+                       {
+                               this.turn = V.GetOppCol(this.turn);
+                               let lastEpsq = this.epSquares[this.epSquares.length-1];
+                               lastEpsq.push(epSq);
+                       }
+                       else
+                               this.epSquares.push([epSq]);
                        this.subTurn = 3 - this.subTurn;
                }
-               this.moves.push(move);
                this.updateVariables(move);
-               if (!!ingame)
-                       move.hash = hex_md5(this.getFen());
-               //console.log(move.checkOnSubturn1 + " " +this.turn + " "+ this.subTurn);
        }
 
        undo(move)
        {
                this.disaggregateFlags(JSON.parse(move.flags));
-               let lastEpsq = this.epSquares[this.epSquares.length-1];
-               if (lastEpsq.length == 2)
-               {
-                       if (!!move.checkOnSubturn1 ||
-                               (this.startAtFirstMove && this.moves.length == 1))
-                       {
-                               this.epSquares.pop(); //remove real + artificial e.p. squares
-                       }
-                       else
-                               lastEpsq.pop();
-               }
-               else
-                       this.epSquares.pop();
                V.UndoOnBoard(this.board, move);
-               if (this.startAtFirstMove && this.moves.length == 1)
-                       this.turn = "w";
-               else if (move.checkOnSubturn1)
-               {
-                       this.turn = this.getOppCol(this.turn);
-                       this.subTurn = 1;
-               }
-               else
+               if (move.turn[1] == '0' || move.checkOnSubturn1 || this.subTurn == 2)
+                       this.epSquares.pop();
+               else //this.subTurn == 1
                {
-                       if (this.subTurn == 1)
-                               this.turn = this.getOppCol(this.turn);
-                       this.subTurn = 3 - this.subTurn;
+                       let lastEpsq = this.epSquares[this.epSquares.length-1];
+                       lastEpsq.pop();
                }
-               this.moves.pop();
+               this.turn = move.turn[0];
+               this.subTurn = parseInt(move.turn[1]);
                this.unupdateVariables(move);
-//             console.log("UNDO " + this.getNotation(move));
-//             console.log(this.turn + " "+ this.subTurn);
        }
 
        // NOTE:  GenRandInitFen() is OK,
        // since at first move turn indicator is just "w"
 
+       static get VALUES()
+       {
+               return {
+                       'p': 1,
+                       'r': 5,
+                       'n': 3,
+                       'b': 3,
+                       'q': 7, //slightly less than in orthodox game
+                       'k': 1000
+               };
+       }
+
        // No alpha-beta here, just adapted min-max at depth 2(+1)
        getComputerMove()
        {
@@ -235,10 +213,11 @@ class MarseilleRules extends ChessRules
 
                const maxeval = V.INFINITY;
                const color = this.turn;
-               const oppCol = this.getOppCol(this.turn);
+               const oppCol = V.GetOppCol(this.turn);
 
                // Search best (half) move for opponent turn
                const getBestMoveEval = () => {
+                       const turnBefore = this.turn + this.subTurn;
                        let moves = this.getAllValidMoves();
                        if (moves.length == 0)
                        {
@@ -251,7 +230,8 @@ class MarseilleRules extends ChessRules
                        for (let m of moves)
                        {
                                this.play(m);
-                               this.turn = color; //very artificial...
+                               // Now turn is oppCol,2 if m doesn't give check
+                               // Otherwise it's color,1. In both cases the next test makes sense
                                if (!this.atLeastOneMove())
                                {
                                        const score = this.checkGameEnd();
@@ -260,14 +240,12 @@ class MarseilleRules extends ChessRules
                                        else
                                        {
                                                // Found a mate
-                                               this.turn = oppCol;
                                                this.undo(m);
                                                return maxeval * (score == "1-0" ? 1 : -1);
                                        }
                                }
                                const evalPos = this.evalPosition();
                                res = (oppCol == "w" ? Math.max(res, evalPos) : Math.min(res, evalPos));
-                               this.turn = oppCol;
                                this.undo(m);
                        }
                        return res;
@@ -278,7 +256,6 @@ class MarseilleRules extends ChessRules
                // Rank moves using a min-max at depth 2
                for (let i=0; i<moves11.length; i++)
                {
-                       moves11[i].eval = (color=="w" ? -1 : 1) * maxeval;
                        this.play(moves11[i]);
                        if (this.turn != color)
                        {
@@ -316,5 +293,3 @@ class MarseilleRules extends ChessRules
                return selected;
        }
 }
-
-const VariantRules = MarseilleRules;