- // TODO: find a more general way to describe pawn movements to avoid
- // re-writing almost the same function for several variants.
- getPotentialPawnMoves([x, y]) {
- const color = this.turn;
- const piece = this.getPiece(x, y);
- let moves = [];
- const [sizeX, sizeY] = [V.size.x, V.size.y];
- const shiftX = color == "w" ? -1 : 1;
- const startRank = color == "w" ? sizeX - 2 : 1;
- const lastRank = color == "w" ? 0 : sizeX - 1;
-
- const finalPieces =
- x + shiftX == lastRank
- ? piece == V.PAWN
- ? [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN]
- : [V.QUEEN] //hidden queen revealed
- : [piece]; //V.PAWN
- if (this.board[x + shiftX][y] == V.EMPTY) {
- // One square forward
- for (let p of finalPieces) {
- moves.push(
- this.getBasicMove([x, y], [x + shiftX, y], {
- c: color,
- p: p
- })
- );
- }
- if (
- x == startRank &&
- this.board[x + 2 * shiftX][y] == V.EMPTY
- ) {
- // 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 p of finalPieces) {
- moves.push(
- this.getBasicMove([x, y], [x + shiftX, y + shiftY], {
- c: color,
- p: p
- })
- );
- }
- }
- }
-
- // En passant