// Local stack of "action moves"
this.amoves = [];
const amove = V.ParseFen(fen).amove;
- if (amove == "-") this.amoves.push(null);
- else {
+ if (amove != "-") {
const amoveParts = amove.split("/");
let amove = {
// No need for start & end
vanish: []
};
[0, 1].map(i => {
- amoveParts[0].split(".").forEach(av => {
+ amoveParts[i].split(".").forEach(av => {
// Format is "bpe3"
const xy = V.SquareToCoords(av.substr(2));
move[i == 0 ? "appear" : "vanish"].push(
});
this.amoves.push(move);
}
+ this.subTurn = 1;
// Stack "first moves" (on subTurn 1) to merge and check opposite moves
this.firstMove = [];
}
static ParseFen(fen) {
return Object.assign(
ChessRules.ParseFen(fen),
- { cmove: fen.split(" ")[4] }
+ { amove: fen.split(" ")[4] }
);
}
return true;
}
- getAmove(move1, move2) {
- // Just merge (one is action one is move, one may be empty)
- return {
- appear: move1.appear.concat(move2.appear),
- vanish: move1.vanish.concat(move2.vanish)
- }
+ getFen() {
+ return super.getFen() + " " + this.getAmoveFen();
}
- doClick(square) {
- // If subTurn == 2 && square is the final square of last move,
- // then return an empty move
- const L = this.firstMove.length;
- if (
- this.subTurn == 2 &&
- square.x == this.firstMove[L-1].end.x &&
- square.y == this.firstMove[L-1].end.y
- ) {
- return {
- appear: [],
- vanish: []
- };
- }
- return null;
+ getFenForRepeat() {
+ return super.getFenForRepeat() + "_" + this.getAmoveFen();
+ }
+
+ getAmoveFen() {
+ const L = this.amoves.length;
+ if (L == 0) return "-";
+ return (
+ ["appear","vanish"].map(
+ mpart => {
+ return (
+ this.amoves[L-1][mpart].map(
+ av => {
+ const square = V.CoordsToSquare({ x: av.x, y: av.y });
+ return av.c + av.p + square;
+ }
+ ).join(".")
+ );
+ }
+ ).join("/")
+ );
}
canTake() {
return false;
}
- // TODO: re-think these next 3 methods:
- // Idea = have the info about lastMove in lastMoves[L-1],
- // In particular if moving a piece or doing an action.
-
- // "pa" : piece (as a square) doing this push/pull action
- getActionMoves([sx, sy], [ex, ey], pa) {
- const color = this.getColor(sx, sy);
- const lastRank = (color == 'w' ? 0 : 7);
- const piece = this.getPiece(sx, sy);
+ // Step is right, just add (push/pull) moves in this direction
+ // Direction is assumed normalized.
+ getMovesInDirection([x, y], [dx, dy], nbSteps) {
+ nbSteps = nbSteps || 8; //max 8 steps anyway
+ let [i, j] = [x + dx, y + dy];
let moves = [];
- if (ex == lastRank && piece == V.PAWN) {
- // Promotion by push or pull
- V.PawnSpecs.promotions.forEach(p => {
- let move = super.getBasicMove([sx, sy], [ex, ey], { c: color, p: p });
- moves.push(move);
- });
- } else moves.push(super.getBasicMove([sx, sy], [ex, ey]));
- const actionType =
- (
- Math.abs(pa[0] - sx) < Math.abs(pa[0] - ex) ||
- Math.abs(pa[1] - sy) < Math.abs(pa[1] - ey)
- )
- ? "push"
- : "pull";
- moves.forEach(m => m.action = [{ by: pa, type: actionType }]);
+ const color = this.getColor(x, y);
+ const piece = this.getPiece(x, y);
+ const lastRank = (color == 'w' ? 0 : 7);
+ let counter = 1;
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ if (i == lastRank && piece == V.PAWN) {
+ // Promotion by push or pull
+ V.PawnSpecs.promotions.forEach(p => {
+ let move = super.getBasicMove([x, y], [i, j], { c: color, p: p });
+ moves.push(move);
+ });
+ }
+ else moves.push(super.getBasicMove([x, y], [i, j]));
+ if (++counter > nbSteps) break;
+ i += dx;
+ j += dy;
+ }
+ if (!V.OnBoard(i, j) && piece != V.KING) {
+ // Add special "exit" move, by "taking king"
+ moves.push(
+ new Move({
+ start: { x: x, y: y },
+ end: { x: this.kingPos[color][0], y: this.kingPos[color][1] },
+ appear: [],
+ vanish: [{ x: x, y: y, c: color, p: piece }]
+ })
+ );
+ }
return moves;
}
- // TODO: if type is given, consider only actions of this type
- getPactions(sq, color, type) {
- const [x, y] = sq;
- let moves = [];
- let squares = {};
- if (!by) {
- const oppCol = V.GetOppCol(color);
- // Look in all directions for a "color" piece
+ // Normalize direction to know the step
+ getNormalizedDirection([dx, dy]) {
+ const absDir = [Math.abs(dx), Math.abs(dy)];
+ let divisor = 0;
+ if (absDir[0] != 0 && absDir[1] != 0 && absDir[0] != absDir[1])
+ // Knight
+ divisor = Math.min(absDir[0], absDir[1]);
+ else
+ // Standard slider (or maybe a pawn or king: same)
+ divisor = Math.max(absDir[0], absDir[1]);
+ return [dx / divisor, dy / divisor];
+ }
+
+ // There is something on x2,y2, maybe our color, pushed/pulled
+ static IsAprioriValidMove([x1, y1], [x2, y2]) {
+ const color1 = this.getColor(x1, y1);
+ const color2 = this.getColor(x2, y2);
+ const pawnShift = (color1 == 'w' ? -1 : 1);
+ const pawnStartRank = (color1 == 'w' ? 6 : 1);
+ const deltaX = Math.abs(x1 - x2);
+ const deltaY = Math.abs(y1 - y2);
+ switch (this.getPiece(x1, y1)) {
+ case V.PAWN:
+ return (
+ (
+ color1 == color2 &&
+ y1 == y2 &&
+ (
+ x1 + pawnShift == x2 ||
+ x1 == pawnStartRank && x1 + 2 * pawnShift == x2
+ )
+ )
+ ||
+ (
+ color1 != color2 &&
+ deltaY == 1 &&
+ x1 + pawnShift == x2
+ )
+ );
+ case V.ROOK:
+ return (x1 == x2 || y1 == y2);
+ case V.KNIGHT: {
+ return (deltaX + deltaY == 3 && (deltaX == 1 || deltaY == 1));
+ }
+ case V.BISHOP:
+ return (deltaX == deltaY);
+ case V.QUEEN:
+ return (
+ (deltaX == 0 || deltaY == 0 || deltaX == deltaY)
+ );
+ case V.KING:
+ return (deltaX <= 1 && deltaY <= 1);
+ }
+ return false;
+ }
+
+ // NOTE: for pushes, play the pushed piece first.
+ // for pulls: play the piece doing the action first
+ // NOTE: to push a piece out of the board, make it slide until its king
+ getPotentialMovesFrom([x, y]) {
+ const color = this.turn;
+ if (this.subTurn == 1) {
+ const getMoveHash = (m) => {
+ return V.CoordsToSquare(m.start) + V.CoordsToSquare(m.end);
+ };
+ const addMoves = (dir, nbSteps) => {
+ const newMoves =
+ this.getMovesInDirection([x, y], [-dir[0], -dir[1]], nbSteps)
+ .filter(m => !movesHash[getMoveHash(m)]);
+ newMoves.forEach(m => { movesHash[getMoveHash(m)] = true; });
+ Array.prototype.push.apply(moves, newMoves);
+ };
+ // Free to play any move:
+ const moves = super.getPotentialMovesFrom([x, y])
+ const pawnShift = (color == 'w' ? -1 : 1);
+ const pawnStartRank = (color == 'w' ? 6 : 1);
+ // Structure to avoid adding moves twice (can be action & move)
+ let movesHash = {};
+ moves.forEach(m => { movesHash[getMoveHash(m)] = true; });
+ // [x, y] is pushed by 'color'
for (let step of V.steps[V.KNIGHT]) {
- const xx = x + step[0],
- yy = y + step[1];
+ const [i, j] = [x + step[0], y + step[1]];
if (
- V.OnBoard(xx, yy) &&
- this.getPiece(xx, yy) == V.KNIGHT &&
- this.getColor(xx, yy) == color
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.KNIGHT
) {
- const px = x - step[0],
- py = y - step[1];
- if (V.OnBoard(px, py)) {
- if (this.board[px][py] == V.EMPTY) {
- const hash = "s" + px + py;
- if (!squares[hash]) {
- squares[hash] = true;
- Array.prototype.push.apply(
- moves,
- this.getActionMoves([x, y], [px, py], [xx, yy])
- );
- }
- else { //add piece doing action
+ addMoves(step, 1);
+ }
+ }
+ for (let step of V.steps[V.ROOK].concat(V.steps[V.BISHOP])) {
+ let [i, j] = [x + step[0], y + step[1]];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i += step[0];
+ j += step[1];
+ }
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color
+ ) {
+ const deltaX = Math.abs(i - x);
+ const deltaY = Math.abs(j - y);
+ // Can a priori go both ways, except with pawns
+ switch (this.getPiece(i, j)) {
+ case V.PAWN:
+ if (deltaX <= 2 && deltaY <= 1) {
+ const pColor = this.getColor(x, y);
+ if (pColor == color && deltaY == 0) {
+ // Pushed forward
+ const maxSteps = (i == pawnStartRank && deltaX == 1 ? 2 : 1);
+ addMoves(step, maxSteps);
+ }
+ else if (pColor != color && deltaY == 1 && deltaX == 1)
+ // Pushed diagonally
+ addMoves(step, 1);
}
- }
- } else {
- const hash = "s" + xx + yy;
- if (!squares[hash]) {
- squares[hash] = true;
- moves.push(
- new Move({
- start: { x: x, y: y },
- end: { x: xx, y: yy },
- appear: [],
- vanish: [
- new PiPo({
- x: x,
- y: y,
- p: this.getPiece(x, y),
- c: oppCol
- })
- ]
- })
- );
- }
+ break;
+ case V.ROOK:
+ if (deltaX == 0 || deltaY == 0) addMoves(step);
+ break;
+ case V.BISHOP:
+ if (deltaX == deltaY) addMoves(step);
+ break;
+ case V.QUEEN:
+ if (deltaX == 0 || deltaY == 0 || deltaX == deltaY)
+ addMoves(step);
+ break;
+ case V.KING:
+ if (deltaX <= 1 && deltaY <= 1) addMoves(step, 1);
+ break;
}
}
}
- for (let step in V.steps[V.ROOK]) {
- // (+ if color is ours, pawn pushes) king, rook and queen
- // --> pawns special case can push from a little distance if on 2nd rank (or 1st rank)
- }
- for (let step in V.steps[V.BISHOP]) {
- // King, bishop, queen, and possibly pawns attacks (if color is enemy)
- }
+ return moves;
}
- return moves;
- }
-
- // NOTE: to push a piece out of the board, make it slide until our piece
- // (doing the action, moving or not)
- // TODO: for pushes, play the pushed piece first.
- // for pulls: play the piece doing the action first
- // If castle, then no options available next (just re-click)
-
- getPotentialMovesFrom([x, y]) {
- const color = this.turn;
- if (this.getColor(x, y) != color)
- // The only moves possible with enemy pieces are pulls and pushes:
- return this.getPactions([x, y], color);
- // Playing my pieces: either on their own, or pushed by another
// If subTurn == 2 then we should have a first move,
- // TODO = use it to allow some type of action
- if (this.subTurn == 2) {
- return (
- this.moveOnSubturn1.isAnAction
- ? super.getPotentialMovesFrom([x, y])
- : this.getPactions([x, y], color, TODO_arg)
- );
+ // which restrict what we can play now: only in the first move direction
+ // NOTE: no need for knight or pawn checks, because the move will be
+ // naturally limited in those cases.
+ const L = this.firstMove.length;
+ const fm = this.firstMove[L-1];
+ if (fm.appear.length == 2 && fm.vanish.length == 2)
+ // Castle: no real move playable then.
+ return [];
+ if (fm.appear.length == 0) {
+ // Piece at subTurn 1 just exited the board.
+ // Can I be a piece which caused the exit?
+ this.undo(fm);
+ const moveOk = V.IsAprioriValidMove([x, y], [fm.start.x, fm.start.y]);
+ this.play(fm);
+ if (moveOk) {
+ // Seems so:
+ const dir = this.getNormalizedDirection(
+ [fm.start.x - x, fm.start.y - y]);
+ return this.getMovesInDirection([x, y], dir);
+ }
}
- // Both options are possible at subTurn1: normal move, or push
- return (
- super.getPotentialMovesFrom([x, y])
- .concat(this.getPactions([x, y], color, "push"))
- // TODO: discard moves that let the king underCheck, and no second
- // move can counter check. Example: pinned queen pushes pinned pawn.
- .filter(m => {
- this.play(m);
- const res = this.filterMoves(this.getPotentialMoves(/* TODO: args? */)).length > 0;
- this.undo(m);
- return res;
- })
- );
+ else {
+ const dirM = this.getNormalizedDirection(
+ [fm.end.x - fm.start.x, fm.end.y - fm.start.y]);
+ const dir = this.getNormalizedDirection(
+ [fm.start.x - x, fm.start.y - y]);
+ // Normalized directions should match:
+ if (dir[0] == dirM[0] && dir[1] == dirM[1])
+ return this.getMovesInDirection([x, y], dir);
+ }
+ return [];
}
// Does m2 un-do m1 ? (to disallow undoing actions)
);
}
+ getAmove(move1, move2) {
+ // Just merge (one is action one is move, one may be empty)
+ return {
+ appear: move1.appear.concat(move2.appear),
+ vanish: move1.vanish.concat(move2.vanish)
+ }
+ }
+
filterValid(moves) {
- if (this.subTurn == 1)
- // Validity of subTurn 1 should be checked in getPotentialMoves
- return moves;
- const L = this.firstMove.length;
+ const color = this.turn;
+ if (this.subTurn == 1) {
+ return moves.filter(m => {
+ // A move is valid either if it doesn't result in a check,
+ // or if a second move is possible to counter the check
+ // (not undoing a potential move + action of the opponent)
+ this.play(m);
+ let res = this.underCheck(color);
+ if (res) {
+ const moves2 = this.getAllPotentialMoves();
+ for (m2 of moves2) {
+ this.play(m2);
+ const res2 = this.underCheck(color);
+ this.undo(m2);
+ if (!res2) {
+ res = false;
+ break;
+ }
+ }
+ }
+ this.undo(m);
+ return !res;
+ });
+ }
+ const Lf = this.firstMove.length;
+ const La = this.amoves.length;
+ if (La == 0) return super.filterValid(moves);
return (
- super.filterMoves(
+ super.filterValid(
moves.filter(m => {
// Move shouldn't undo another:
- return !this.oppositeMoves(this.firstMove[L-1], m)
+ const amove = this.getAmove(this.firstMove[Lf-1], m);
+ return !this.oppositeMoves(this.amoves[La-1], amove);
})
)
);
return super.getCurrentScore();
}
+ doClick(square) {
+ // If subTurn == 2 && square is empty && !underCheck,
+ // then return an empty move, allowing to "pass" subTurn2
+ if (
+ this.subTurn == 2 &&
+ this.board[square[0]][square[1]] == V.EMPTY &&
+ !this.underCheck(this.turn)
+ ) {
+ return {
+ start: { x: -1, y: -1 },
+ end: { x: -1, y: -1 },
+ appear: [],
+ vanish: []
+ };
+ }
+ return null;
+ }
+
play(move) {
move.flags = JSON.stringify(this.aggregateFlags());
V.PlayOnBoard(this.board, move);
if (this.subTurn == 2) {
+ const L = this.firstMove.length;
+ this.amoves.push(this.getAmove(this.firstMove[L-1], move));
this.turn = V.GetOppCol(this.turn);
this.movesCount++;
}
this.postPlay(move);
}
- updateCastleFlags(move, piece) {
- const c = V.GetOppCol(this.turn);
- const firstRank = (c == "w" ? V.size.x - 1 : 0);
- // Update castling flags
- if (piece == V.KING) this.castleFlags[c] = [V.size.y, V.size.y];
+ postPlay(move) {
+ if (move.start.x < 0) return;
+ for (let a of move.appear)
+ if (a.p == V.KING) this.kingPos[a.c] = [a.x, a.y];
+ this.updateCastleFlags(move);
+ }
+
+ updateCastleFlags(move) {
+ const firstRank = { 'w': V.size.x - 1, 'b': 0 };
for (let v of move.vanish) {
- if (v.x == firstRank && this.castleFlags[c].includes(v.y)) {
- const flagIdx = (v.y == this.castleFlags[c][0] ? 0 : 1);
- this.castleFlags[c][flagIdx] = V.size.y;
+ if (v.p == V.KING) this.castleFlags[v.c] = [V.size.y, V.size.y];
+ else if (v.x == firstRank[v.c] && this.castleFlags[v.c].includes(v.y)) {
+ const flagIdx = (v.y == this.castleFlags[v.c][0] ? 0 : 1);
+ this.castleFlags[v.c][flagIdx] = V.size.y;
}
}
}
this.subTurn = 3 - this.subTurn;
this.postUndo(move);
}
+
+ postUndo(move) {
+ // (Potentially) Reset king position
+ for (let v of move.vanish)
+ if (v.p == V.KING) this.kingPos[v.c] = [v.x, v.y];
+ }
+
+ getNotation(move) {
+ if (move.start.x < 0)
+ // A second move is always required, but may be empty
+ return "-";
+ const initialSquare = V.CoordsToSquare(move.start);
+ const finalSquare = V.CoordsToSquare(move.end);
+ if (move.appear.length == 0)
+ // Pushed or pulled out of the board
+ return initialSquare + "R";
+ return move.appear[0].p.toUpperCase() + initialSquare + finalSquare;
+ }
};