X-Git-Url: https://git.auder.net/?a=blobdiff_plain;f=public%2Fjavascripts%2Fvariants%2FMagnetic.js;h=17efeaa923918e94506cc4768b468e8a8a8381a9;hb=643479f8d7c3622b57fc49c4f10d9950793ebf4f;hp=e94153229532d42acaf32dd1c06ea6f7ae0717de;hpb=1af36beb39aa5d59735483e915fd1040f93eecca;p=vchess.git

diff --git a/public/javascripts/variants/Magnetic.js b/public/javascripts/variants/Magnetic.js
index e9415322..17efeaa9 100644
--- a/public/javascripts/variants/Magnetic.js
+++ b/public/javascripts/variants/Magnetic.js
@@ -1,128 +1,212 @@
-class MagneticRules
+class MagneticRules extends ChessRules
 {
-	getEpSquare(move)
-	{
-		return undefined; //no en-passant
-	}
+	static get HasEnpassant { return false; }
 
-	// Complete a move with magnetic actions
-	applyMagneticLaws([x,y], move)
+	setOtherVariables(fen)
 	{
-		// TODO
+		// No en-passant:
+		const parsedFen = V.ParseFen(fen);
+		this.setFlags(fenParsed.flags);
+		this.scanKingsRooks(fen);
 	}
 
-	getBasicMove([sx,sy], [ex,ey], tr)
+	getPotentialMovesFrom([x,y])
 	{
-		var mv = new Move({
-			appear: [
-				new PiPo({
-					x: ex,
-					y: ey,
-					c: !!tr ? tr.c : this.getColor(sx,sy),
-					p: !!tr ? tr.p : this.getPiece(sx,sy)
-				})
-			],
-			vanish: [
-				new PiPo({
-					x: sx,
-					y: sy,
-					c: this.getColor(sx,sy),
-					p: this.getPiece(sx,sy)
-				})
-			]
+		let standardMoves = super.getPotentialMovesFrom([x,y]);
+		let moves = [];
+		standardMoves.forEach(m => {
+			let newMove_s = this.applyMagneticLaws(m);
+			if (newMove_s.length == 1)
+				moves.push(newMove_s[0]);
+			else //promotion
+				moves = moves.concat(newMove_s);
 		});
-
-		if (this.board[ex][ey] != VariantRules.EMPTY)
-		{
-			mv.vanish.push(
-				new PiPo({
-					x: ex,
-					y: ey,
-					c: this.getColor(ex,ey),
-					p: this.getPiece(ex,ey)
-				})
-			);
-		}
-		this.applyMagneticLaws([ex,ey], mv);
-		return mv;
+		return moves;
 	}
 
-	getCastleMoves([x,y])
+	getPotentialPawnMoves([x,y])
 	{
-		const c = this.getColor(x,y);
-		if (x != (c=="w" ? 7 : 0) || y != this.INIT_COL_KING[c])
-			return []; //x isn't first rank, or king has moved (shortcut)
-
-		const V = VariantRules;
-
-		// Castling ?
-		const oppCol = this.getOppCol(c);
+		const color = this.turn;
 		let moves = [];
-		let i = 0;
-		const finalSquares = [ [2,3], [6,5] ]; //king, then rook
-		castlingCheck:
-		for (let castleSide=0; castleSide < 2; castleSide++) //large, then small
-		{
-			if (!this.flags[c][castleSide])
-				continue;
-			// If this code is reached, rooks and king are on initial position
+		const [sizeX,sizeY] = [V.size.x,V.size.y];
+		const shift = (color == "w" ? -1 : 1);
+		const firstRank = (color == 'w' ? sizeX-1 : 0);
+		const startRank = (color == "w" ? sizeX-2 : 1);
+		const lastRank = (color == "w" ? 0 : sizeX-1);
 
-			// Nothing on the path of the king (and no checks; OK also if y==finalSquare)?
-			let step = finalSquares[castleSide][0] < y ? -1 : 1;
-			for (i=y; i!=finalSquares[castleSide][0]; i+=step)
+		if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRank)
+		{
+			// Normal moves
+			if (this.board[x+shift][y] == V.EMPTY)
 			{
-				if (this.isAttacked([x,i], oppCol) || (this.board[x][i] != V.EMPTY &&
-					// NOTE: next check is enough, because of chessboard constraints
-					(this.getColor(x,i) != c || ![V.KING,V.ROOK].includes(this.getPiece(x,i)))))
+				moves.push(this.getBasicMove([x,y], [x+shift,y]));
+				// Next condition because variants with pawns on 1st rank allow them to jump
+				if ([startRank,firstRank].includes(x) && this.board[x+2*shift][y] == V.EMPTY)
 				{
-					continue castlingCheck;
+					// Two squares jump
+					moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
 				}
 			}
-
-			// Nothing on the path to the rook?
-			step = castleSide == 0 ? -1 : 1;
-			for (i = y + step; i != this.INIT_COL_ROOK[c][castleSide]; i += step)
+			// Captures
+			if (y>0 && this.board[x+shift][y-1] != V.EMPTY
+				&& this.canTake([x,y], [x+shift,y-1]))
 			{
-				if (this.board[x][i] != V.EMPTY)
-					continue castlingCheck;
+				moves.push(this.getBasicMove([x,y], [x+shift,y-1]));
 			}
-			const rookPos = this.INIT_COL_ROOK[c][castleSide];
-
-			// Nothing on final squares, except maybe king and castling rook?
-			for (i=0; i<2; i++)
+			if (y<sizeY-1 && this.board[x+shift][y+1] != V.EMPTY
+				&& this.canTake([x,y], [x+shift,y+1]))
 			{
-				if (this.board[x][finalSquares[castleSide][i]] != V.EMPTY &&
-					this.getPiece(x,finalSquares[castleSide][i]) != V.KING &&
-					finalSquares[castleSide][i] != rookPos)
-				{
-					continue castlingCheck;
-				}
+				moves.push(this.getBasicMove([x,y], [x+shift,y+1]));
 			}
+		}
 
-			// If this code is reached, castle is valid
-			let cmove = new Move({
-				appear: [
-					new PiPo({x:x,y:finalSquares[castleSide][0],p:V.KING,c:c}),
-					new PiPo({x:x,y:finalSquares[castleSide][1],p:V.ROOK,c:c})],
-				vanish: [
-					new PiPo({x:x,y:y,p:V.KING,c:c}),
-					new PiPo({x:x,y:rookPos,p:V.ROOK,c:c})],
-				end: Math.abs(y - rookPos) <= 2
-					? {x:x, y:rookPos}
-					: {x:x, y:y + 2 * (castleSide==0 ? -1 : 1)}
+		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:pawnColor,p:p}));
+				// Captures
+				if (y>0 && this.board[x+shift][y-1] != V.EMPTY
+					&& this.canTake([x,y], [x+shift,y-1]))
+				{
+					moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:pawnColor,p:p}));
+				}
+				if (y<sizeY-1 && this.board[x+shift][y+1] != V.EMPTY
+					&& this.canTake([x,y], [x+shift,y+1]))
+				{
+					moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:pawnColor,p:p}));
+				}
 			});
-			this.applyMagneticLaws([x,finalSquares[castleSide][1]], cmove);
-			moves.push(cmove);
 		}
+		return moves; //no en-passant
+	}
 
+	// Complete a move with magnetic actions
+	// TODO: job is done multiple times for (normal) promotions.
+	applyMagneticLaws(move)
+	{
+		if (move.appear[0].p == V.KING && move.appear.length==1)
+			return [move]; //kings are not charged
+		const aIdx = (move.appear[0].p != V.KING ? 0 : 1); //if castling, rook is charged
+		const [x,y] = [move.appear[aIdx].x, move.appear[aIdx].y];
+		const color = this.turn;
+		const lastRank = (color=="w" ? 0 : 7);
+		const standardMove = JSON.parse(JSON.stringify(move));
+		this.play(standardMove);
+		for (let step of [[-1,0],[1,0],[0,-1],[0,1]])
+		{
+			let [i,j] = [x+step[0],y+step[1]];
+			while (V.OnBoard(i,j))
+			{
+				if (this.board[i][j] != V.EMPTY)
+				{
+					// Found something. Same color or not?
+					if (this.getColor(i,j) != color)
+					{
+						// Attraction
+						if ((Math.abs(i-x)>=2 || Math.abs(j-y)>=2) && this.getPiece(i,j) != V.KING)
+						{
+							move.vanish.push(
+								new PiPo({
+									p:this.getPiece(i,j),
+									c:this.getColor(i,j),
+									x:i,
+									y:j
+								})
+							);
+							move.appear.push(
+								new PiPo({
+									p:this.getPiece(i,j),
+									c:this.getColor(i,j),
+									x:x+step[0],
+									y:y+step[1]
+								})
+							);
+						}
+					}
+					else
+					{
+						// Repulsion
+						if (this.getPiece(i,j) != V.KING)
+						{
+							// Push it until we meet an obstacle or edge of the board
+							let [ii,jj] = [i+step[0],j+step[1]];
+							while (V.OnBoard(ii,jj))
+							{
+								if (this.board[ii][jj] != V.EMPTY)
+									break;
+								ii += step[0];
+								jj += step[1];
+							}
+							ii -= step[0];
+							jj -= step[1];
+							if (Math.abs(ii-i)>=1 || Math.abs(jj-j)>=1)
+							{
+								move.vanish.push(
+									new PiPo({
+										p:this.getPiece(i,j),
+										c:this.getColor(i,j),
+										x:i,
+										y:j
+									})
+								);
+								move.appear.push(
+									new PiPo({
+										p:this.getPiece(i,j),
+										c:this.getColor(i,j),
+										x:ii,
+										y:jj
+									})
+								);
+							}
+						}
+					}
+					break;
+				}
+				i += step[0];
+				j += step[1];
+			}
+		}
+		this.undo(standardMove);
+		let moves = [];
+		// Scan move for pawn (max 1) on 8th rank
+		for (let i=1; i<move.appear.length; i++)
+		{
+			if (move.appear[i].p==V.PAWN && move.appear[i].c==color
+				&& move.appear[i].x==lastRank)
+			{
+				move.appear[i].p = V.ROOK;
+				moves.push(move);
+				for (let piece of [V.KNIGHT, V.BISHOP, V.QUEEN])
+				{
+					let cmove = JSON.parse(JSON.stringify(move));
+					cmove.appear[i].p = piece;
+					moves.push(cmove);
+				}
+				// Swap appear[i] and appear[0] for moves presentation (TODO: this is awkward)
+				moves.forEach(m => {
+					let tmp = m.appear[0];
+					m.appear[0] = m.appear[i];
+					m.appear[i] = tmp;
+				});
+				break;
+			}
+		}
+		if (moves.length == 0) //no pawn on 8th rank
+			moves.push(move);
 		return moves;
 	}
 
-	// TODO: verify this assertion
-//	atLeastOneMove()
-//	{
-//		return true; //always at least one possible move
-//	}
+	atLeastOneMove()
+	{
+		if (this.kingPos[this.turn][0] < 0)
+			return false;
+		return true; //TODO: is it right?
+	}
 
 	underCheck(move)
 	{
@@ -135,9 +219,9 @@ class MagneticRules
 		const saveKingPos = this.kingPos[c]; //king might be taken
 		this.play(move);
 		// The only way to be "under check" is to have lost the king (thus game over)
-		let res = this.kingPos[c][0] < 0;
-			? [ JSON.parse(JSON.stringify(saveKingPos)) ]
-			: [ ];
+		let res = this.kingPos[c][0] < 0
+			? [JSON.parse(JSON.stringify(saveKingPos))]
+			: [];
 		this.undo(move);
 		return res;
 	}
@@ -146,15 +230,25 @@ class MagneticRules
 	{
 		super.updateVariables(move);
 		const c = this.getColor(move.start.x,move.start.y);
-		if (c != this.getColor(move.end.x,move.end.y)
-			&& this.board[move.end.x][move.end.y] != VariantRules.EMPTY
-			&& this.getPiece(move.end.x,move.end.y) == VariantRules.KING)
+		if (this.board[move.end.x][move.end.y] != V.EMPTY
+			&& c != this.getColor(move.end.x,move.end.y)
+			&& this.getPiece(move.end.x,move.end.y) == V.KING)
 		{
 			// We took opponent king !
 			const oppCol = this.getOppCol(c);
 			this.kingPos[oppCol] = [-1,-1];
-			this.flags[oppCol] = [false,false];
+			this.castleFlags[oppCol] = [false,false];
 		}
+		// Did we magnetically move our (init) rooks or opponents' ones ?
+		const firstRank = (c == "w" ? 7 : 0);
+		const oppFirstRank = 7 - firstRank;
+		const oppCol = this.getOppCol(c);
+		move.vanish.forEach(psq => {
+			if (psq.x == firstRank && this.INIT_COL_ROOK[c].includes(psq.y))
+				this.castleFlags[c][psq.y==this.INIT_COL_ROOK[c][0] ? 0 : 1] = false;
+			else if (psq.x == oppFirstRank && this.INIT_COL_ROOK[oppCol].includes(psq.y))
+				this.castleFlags[oppCol][psq.y==this.INIT_COL_ROOK[oppCol][0] ? 0 : 1] = false;
+		});
 	}
 
 	unupdateVariables(move)
@@ -176,22 +270,16 @@ class MagneticRules
 		}
 	}
 
-	checkGameOver()
-	{
-		if (this.checkRepetition())
-			return "1/2";
-
-		const color = this.turn;
-		// TODO: do we need "atLeastOneMove()"?
-		if (this.atLeastOneMove() && this.kingPos[color][0] >= 0)
-			return "*";
-
-		return this.checkGameEnd();
-	}
-
 	checkGameEnd()
 	{
 		// No valid move: our king disappeared
 		return this.turn == "w" ? "0-1" : "1-0";
 	}
+
+	static get THRESHOLD_MATE()
+	{
+		return 500; //checkmates evals may be slightly below 1000
+	}
 }
+
+const VariantRules = MagneticRules;