if (x+shift == lastRank)
{
// Promotion
+ const pawnColor = this.getColor(x,y); //can be different for checkered
let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN];
promotionPieces.forEach(p => {
// Normal move
if (this.board[x+shift][y] == V.EMPTY)
- moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,p:p}));
+ moves.push(this.getBasicMove([x,y], [x+shift,y], {c:pawnColor,p:p}));
// Captures
if (y>0 && this.canTake([x,y], [x+shift,y-1])
&& this.board[x+shift][y-1] != V.EMPTY)
{
- moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:color,p:p}));
+ moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:pawnColor,p:p}));
}
if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
&& this.board[x+shift][y+1] != V.EMPTY)
{
- moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:color,p:p}));
+ moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:pawnColor,p:p}));
}
});
}
for (let i=0; i<moves1.length; i++)
{
moves1[i].eval = (color=="w" ? -1 : 1) * maxeval; //very low, I'm checkmated
- let eval2 = (color=="w" ? 1 : -1) * maxeval; //initialized with checkmate value
this.play(moves1[i]);
- // Second half-move:
- let moves2 = this.getAllValidMoves();
- // If no possible moves AND underCheck, eval2 is correct.
- // If !underCheck, eval2 is 0 (stalemate).
- if (moves2.length == 0 && this.checkGameEnd() == "1/2")
- eval2 = 0;
- for (let j=0; j<moves2.length; j++)
+ let eval2 = undefined;
+ if (this.atLeastOneMove())
{
- this.play(moves2[j]);
- let evalPos = this.atLeastOneMove()
- ? this.evalPosition("yes")
- : (this.checkGameEnd()=="1/2" ? 0 : (this.turn=="w"?-maxeval:maxeval));
- if ((color == "w" && evalPos < eval2) || (color=="b" && evalPos > eval2))
- eval2 = evalPos;
- this.undo(moves2[j]);
+ eval2 = (color=="w" ? 1 : -1) * maxeval; //initialized with checkmate value
+ // Second half-move:
+ let moves2 = this.getAllValidMoves();
+ for (let j=0; j<moves2.length; j++)
+ {
+ this.play(moves2[j]);
+ let evalPos = undefined;
+ if (this.atLeastOneMove())
+ evalPos = this.evalPosition()
+ else
+ {
+ // Work with scores for Loser variant
+ const score = this.checkGameEnd();
+ evalPos = (score=="1/2" ? 0 : (score=="1-0" ? 1 : -1) * maxeval);
+ }
+ if ((color == "w" && evalPos < eval2) || (color=="b" && evalPos > eval2))
+ eval2 = evalPos;
+ this.undo(moves2[j]);
+ }
+ }
+ else
+ {
+ const score = this.checkGameEnd();
+ eval2 = (score=="1/2" ? 0 : (score=="1-0" ? 1 : -1) * maxeval);
}
if ((color=="w" && eval2 > moves1[i].eval) || (color=="b" && eval2 < moves1[i].eval))
moves1[i].eval = eval2;
}
else
return currentBest;
- //console.log(moves1.map(m => { return [this.getNotation(m)[0], m.eval]; }));
+ //console.log(moves1.map(m => { return [this.getNotation(m), m.eval]; }));
candidates = [0];
for (let j=1; j<moves1.length && moves1[j].eval == moves1[0].eval; j++)
{
switch (this.checkGameEnd())
{
- case "1/2": return 0;
- default: return color=="w" ? -maxeval : maxeval;
+ case "1/2":
+ return 0;
+ default:
+ const score = this.checkGameEnd();
+ return (score=="1/2" ? 0 : (score=="1-0" ? 1 : -1) * maxeval);
}
}
if (depth == 0)