X-Git-Url: https://git.auder.net/?a=blobdiff_plain;f=public%2Fjavascripts%2Fvariants%2FUltima.js;h=d6fecb70d49d5c74eb7f1509ee7358190176393c;hb=7931e479adf93c87771ded1892a0873af72ae46d;hp=4612da1004e273d10c5ee298b9fc103a0fb9836f;hpb=45338cdd7f037ba7b8c9e25d000ce351d86567a6;p=vchess.git

diff --git a/public/javascripts/variants/Ultima.js b/public/javascripts/variants/Ultima.js
index 4612da10..d6fecb70 100644
--- a/public/javascripts/variants/Ultima.js
+++ b/public/javascripts/variants/Ultima.js
@@ -7,6 +7,15 @@ class UltimaRules extends ChessRules
 		return b; //usual piece
 	}
 
+	static get PIECES() {
+		return ChessRules.PIECES.concat([V.IMMOBILIZER]);
+	}
+
+	static IsGoodFlags(flags)
+	{
+		return true; //anything is good: no flags
+	}
+
 	initVariables(fen)
 	{
 		this.kingPos = {'w':[-1,-1], 'b':[-1,-1]};
@@ -50,21 +59,58 @@ class UltimaRules extends ChessRules
 	//  - a "bishop" is a chameleon, capturing as its prey
 	//  - a "queen" is a withdrawer, capturing by moving away from pieces
 
+	// Is piece on square (x,y) immobilized?
+	isImmobilized([x,y])
+	{
+		const piece = this.getPiece(x,y);
+		const color = this.getColor(x,y);
+		const oppCol = this.getOppCol(color);
+		const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		outerLoop:
+		for (let step of adjacentSteps)
+		{
+			const [i,j] = [x+step[0],y+step[1]];
+			if (V.OnBoard(i,j) && this.board[i][j] != V.EMPTY
+				&& this.getColor(i,j) == oppCol)
+			{
+				const oppPiece = this.getPiece(i,j);
+				if (oppPiece == V.IMMOBILIZER)
+				{
+					// Moving is impossible only if this immobilizer is not neutralized
+					for (let step2 of adjacentSteps)
+					{
+						const [i2,j2] = [i+step2[0],j+step2[1]];
+						if (i2 == x && j2 == y)
+							continue; //skip initial piece!
+						if (V.OnBoard(i2,j2) && this.board[i2][j2] != V.EMPTY
+							&& this.getColor(i2,j2) == color)
+						{
+							if ([V.BISHOP,V.IMMOBILIZER].includes(this.getPiece(i2,j2)))
+								return false;
+						}
+					}
+					return true; //immobilizer isn't neutralized
+				}
+				// Chameleons can't be immobilized twice, because there is only one immobilizer
+				if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER)
+					return true;
+			}
+		}
+		return false;
+	}
+
 	getPotentialMovesFrom([x,y])
 	{
-		// TODO: pre-check: is thing on this square immobilized? If yes, return []
+		// Pre-check: is thing on this square immobilized?
+		if (this.isImmobilized([x,y]))
+			return [];
 		switch (this.getPiece(x,y))
 		{
-			case VariantRules.IMMOBILIZER:
+			case V.IMMOBILIZER:
 				return this.getPotentialImmobilizerMoves([x,y]);
 			default:
 				return super.getPotentialMovesFrom([x,y]);
 		}
-		// TODO: add potential suicides as a move "taking the immobilizer"
-		// TODO: add long-leaper captures
-		// TODO: mark matching coordinator/withdrawer/chameleon moves as captures
-		// (will be a bit tedious for chameleons)
-		// --> filter directly in functions below
 	}
 
 	getSlideNJumpMoves([x,y], steps, oneStep)
@@ -72,14 +118,12 @@ class UltimaRules extends ChessRules
 		const color = this.getColor(x,y);
 		const piece = this.getPiece(x,y);
 		let moves = [];
-		const [sizeX,sizeY] = VariantRules.size;
 		outerLoop:
 		for (let step of steps)
 		{
 			let i = x + step[0];
 			let j = y + step[1];
-			while (i>=0 && i<sizeX && j>=0 && j<sizeY
-				&& this.board[i][j] == VariantRules.EMPTY)
+			while (V.OnBoard(i,j) && this.board[i][j] == V.EMPTY)
 			{
 				moves.push(this.getBasicMove([x,y], [i,j]));
 				if (oneStep !== undefined)
@@ -88,48 +132,246 @@ class UltimaRules extends ChessRules
 				j += step[1];
 			}
 			// Only king can take on occupied square:
-			if (piece==VariantRules.KING && i>=0 && i<sizeX && j>=0
-				&& j<sizeY && this.canTake([x,y], [i,j]))
-			{
+			if (piece==V.KING && V.OnBoard(i,j) && this.canTake([x,y], [i,j]))
 				moves.push(this.getBasicMove([x,y], [i,j]));
-			}
 		}
 		return moves;
 	}
 
+	// Modify capturing moves among listed pawn moves
+	addPawnCaptures(moves, byChameleon)
+	{
+		const steps = V.steps[V.ROOK];
+		const color = this.turn;
+		const oppCol = this.getOppCol(color);
+		moves.forEach(m => {
+			if (!!byChameleon && m.start.x!=m.end.x && m.start.y!=m.end.y)
+				return; //chameleon not moving as pawn
+			// Try capturing in every direction
+			for (let step of steps)
+			{
+				const sq2 = [m.end.x+2*step[0],m.end.y+2*step[1]];
+				if (V.OnBoard(sq2[0],sq2[1]) && this.board[sq2[0]][sq2[1]] != V.EMPTY
+					&& this.getColor(sq2[0],sq2[1]) == color)
+				{
+					// Potential capture
+					const sq1 = [m.end.x+step[0],m.end.y+step[1]];
+					if (this.board[sq1[0]][sq1[1]] != V.EMPTY
+						&& this.getColor(sq1[0],sq1[1]) == oppCol)
+					{
+						const piece1 = this.getPiece(sq1[0],sq1[1]);
+						if (!byChameleon || piece1 == V.PAWN)
+						{
+							m.vanish.push(new PiPo({
+								x:sq1[0],
+								y:sq1[1],
+								c:oppCol,
+								p:piece1
+							}));
+						}
+					}
+				}
+			}
+		});
+	}
+
+	// "Pincher"
 	getPotentialPawnMoves([x,y])
 	{
-		return super.getPotentialRookMoves([x,y]);
+		let moves = super.getPotentialRookMoves([x,y]);
+		this.addPawnCaptures(moves);
+		return moves;
 	}
 
+	addRookCaptures(moves, byChameleon)
+	{
+		const color = this.turn;
+		const oppCol = this.getOppCol(color);
+		const kp = this.kingPos[color];
+		moves.forEach(m => {
+			// Check piece-king rectangle (if any) corners for enemy pieces
+			if (m.end.x == kp[0] || m.end.y == kp[1])
+				return; //"flat rectangle"
+			const corner1 = [m.end.x, kp[1]];
+			const corner2 = [kp[0], m.end.y];
+			for (let [i,j] of [corner1,corner2])
+			{
+				if (this.board[i][j] != V.EMPTY && this.getColor(i,j) == oppCol)
+				{
+					const piece = this.getPiece(i,j);
+					if (!byChameleon || piece == V.ROOK)
+					{
+						m.vanish.push( new PiPo({
+							x:i,
+							y:j,
+							p:piece,
+							c:oppCol
+						}) );
+					}
+				}
+			}
+		});
+	}
+
+	// Coordinator
 	getPotentialRookMoves(sq)
 	{
-		return super.getPotentialQueenMoves(sq);
+		let moves = super.getPotentialQueenMoves(sq);
+		this.addRookCaptures(moves);
+		return moves;
 	}
 
+	// Long-leaper
+	getKnightCaptures(startSquare, byChameleon)
+	{
+		// Look in every direction for captures
+		const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		const color = this.turn;
+		const oppCol = this.getOppCol(color);
+		let moves = [];
+		const [x,y] = [startSquare[0],startSquare[1]];
+		const piece = this.getPiece(x,y); //might be a chameleon!
+		outerLoop:
+		for (let step of steps)
+		{
+			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.getColor(i,j)==color
+				|| (!!byChameleon && this.getPiece(i,j)!=V.KNIGHT))
+			{
+				continue;
+			}
+			// last(thing), cur(thing) : stop if "cur" is our color, or beyond board limits,
+			// or if "last" isn't empty and cur neither. Otherwise, if cur is empty then
+			// add move until cur square; if cur is occupied then stop if !!byChameleon and
+			// the square not occupied by a leaper.
+			let last = [i,j];
+			let cur = [i+step[0],j+step[1]];
+			let vanished = [ new PiPo({x:x,y:y,c:color,p:piece}) ];
+			while (V.OnBoard(cur[0],cur[1]))
+			{
+				if (this.board[last[0]][last[1]] != V.EMPTY)
+				{
+					const oppPiece = this.getPiece(last[0],last[1]);
+					if (!!byChameleon && oppPiece != V.KNIGHT)
+						continue outerLoop;
+					// Something to eat:
+					vanished.push( new PiPo({x:last[0],y:last[1],c:oppCol,p:oppPiece}) );
+				}
+				if (this.board[cur[0]][cur[1]] != V.EMPTY)
+				{
+					if (this.getColor(cur[0],cur[1]) == color
+						|| this.board[last[0]][last[1]] != V.EMPTY) //TODO: redundant test
+					{
+						continue outerLoop;
+					}
+				}
+				else
+				{
+					moves.push(new Move({
+						appear: [ new PiPo({x:cur[0],y:cur[1],c:color,p:piece}) ],
+						vanish: JSON.parse(JSON.stringify(vanished)), //TODO: required?
+						start: {x:x,y:y},
+						end: {x:cur[0],y:cur[1]}
+					}));
+				}
+				last = [last[0]+step[0],last[1]+step[1]];
+				cur = [cur[0]+step[0],cur[1]+step[1]];
+			}
+		}
+		return moves;
+	}
+
+	// Long-leaper
 	getPotentialKnightMoves(sq)
 	{
-		return super.getPotentialQueenMoves(sq);
+		return super.getPotentialQueenMoves(sq).concat(this.getKnightCaptures(sq));
 	}
 
-	getPotentialBishopMoves(sq)
+	getPotentialBishopMoves([x,y])
 	{
-		return super.getPotentialQueenMoves(sq);
+		let moves = super.getPotentialQueenMoves([x,y])
+			.concat(this.getKnightCaptures([x,y],"asChameleon"));
+		// No "king capture" because king cannot remain under check
+		this.addPawnCaptures(moves, "asChameleon");
+		this.addRookCaptures(moves, "asChameleon");
+		this.addQueenCaptures(moves, "asChameleon");
+		// Post-processing: merge similar moves, concatenating vanish arrays
+		let mergedMoves = {};
+		moves.forEach(m => {
+			const key = m.end.x + V.size.x * m.end.y;
+			if (!mergedMoves[key])
+				mergedMoves[key] = m;
+			else
+			{
+				for (let i=1; i<m.vanish.length; i++)
+					mergedMoves[key].vanish.push(m.vanish[i]);
+			}
+		});
+		// Finally return an array
+		moves = [];
+		Object.keys(mergedMoves).forEach(k => { moves.push(mergedMoves[k]); });
+		return moves;
+	}
+
+	// Withdrawer
+	addQueenCaptures(moves, byChameleon)
+	{
+		if (moves.length == 0)
+			return;
+		const [x,y] = [moves[0].start.x,moves[0].start.y];
+		const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		let capturingDirections = [];
+		const color = this.turn;
+		const oppCol = this.getOppCol(color);
+		adjacentSteps.forEach(step => {
+			const [i,j] = [x+step[0],y+step[1]];
+			if (V.OnBoard(i,j) && this.board[i][j] != V.EMPTY && this.getColor(i,j) == oppCol
+				&& (!byChameleon || this.getPiece(i,j) == V.QUEEN))
+			{
+				capturingDirections.push(step);
+			}
+		});
+		moves.forEach(m => {
+			const step = [
+				m.end.x!=x ? (m.end.x-x)/Math.abs(m.end.x-x) : 0,
+				m.end.y!=y ? (m.end.y-y)/Math.abs(m.end.y-y) : 0
+			];
+			// NOTE: includes() and even _.isEqual() functions fail...
+			// TODO: this test should be done only once per direction
+			if (capturingDirections.some(dir =>
+				{ return (dir[0]==-step[0] && dir[1]==-step[1]); }))
+			{
+				const [i,j] = [x-step[0],y-step[1]];
+				m.vanish.push(new PiPo({
+					x:i,
+					y:j,
+					p:this.getPiece(i,j),
+					c:oppCol
+				}));
+			}
+		});
 	}
 
 	getPotentialQueenMoves(sq)
 	{
-		return super.getPotentialQueenMoves(sq);
+		let moves = super.getPotentialQueenMoves(sq);
+		this.addQueenCaptures(moves);
+		return moves;
 	}
 
 	getPotentialImmobilizerMoves(sq)
 	{
+		// Immobilizer doesn't capture
 		return super.getPotentialQueenMoves(sq);
 	}
 
 	getPotentialKingMoves(sq)
 	{
-		const V = VariantRules;
 		return this.getSlideNJumpMoves(sq,
 			V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
 	}
@@ -138,41 +380,164 @@ class UltimaRules extends ChessRules
 
 	isAttackedByPawn([x,y], colors)
 	{
-		// Square (x,y) must be surrounded by two enemy pieces,
-		// and one of them at least should be a pawn
+		// Square (x,y) must be surroundable by two enemy pieces,
+		// and one of them at least should be a pawn (moving).
+		const dirs = [ [1,0],[0,1] ];
+		const steps = V.steps[V.ROOK];
+		for (let dir of dirs)
+		{
+			const [i1,j1] = [x-dir[0],y-dir[1]]; //"before"
+			const [i2,j2] = [x+dir[0],y+dir[1]]; //"after"
+			if (V.OnBoard(i1,j1) && V.OnBoard(i2,j2))
+			{
+				if ((this.board[i1][j1]!=V.EMPTY && colors.includes(this.getColor(i1,j1))
+					&& this.board[i2][j2]==V.EMPTY)
+						||
+					(this.board[i2][j2]!=V.EMPTY && colors.includes(this.getColor(i2,j2))
+					&& this.board[i1][j1]==V.EMPTY))
+				{
+					// Search a movable enemy pawn landing on the empty square
+					for (let step of steps)
+					{
+						let [ii,jj] = (this.board[i1][j1]==V.EMPTY ? [i1,j1] : [i2,j2]);
+						let [i3,j3] = [ii+step[0],jj+step[1]];
+						while (V.OnBoard(i3,j3) && this.board[i3][j3]==V.EMPTY)
+						{
+							i3 += step[0];
+							j3 += step[1];
+						}
+						if (V.OnBoard(i3,j3) && colors.includes(this.getColor(i3,j3))
+							&& this.getPiece(i3,j3) == V.PAWN && !this.isImmobilized([i3,j3]))
+						{
+							return true;
+						}
+					}
+				}
+			}
+		}
 		return false;
 	}
 
-	isAttackedByRook(sq, colors)
+	isAttackedByRook([x,y], colors)
 	{
-		// Enemy king must be on same file and a rook on same row (or reverse)
+		// King must be on same column or row,
+		// and a rook should be able to reach a capturing square
+		// colors contains only one element, giving the oppCol and thus king position
+		const sameRow = (x == this.kingPos[colors[0]][0]);
+		const sameColumn = (y == this.kingPos[colors[0]][1]);
+		if (sameRow || sameColumn)
+		{
+			// Look for the enemy rook (maximum 1)
+			for (let i=0; i<V.size.x; i++)
+			{
+				for (let j=0; j<V.size.y; j++)
+				{
+					if (this.board[i][j] != V.EMPTY && colors.includes(this.getColor(i,j))
+						&& this.getPiece(i,j) == V.ROOK)
+					{
+						if (this.isImmobilized([i,j]))
+							return false; //because only one rook
+						// Can it reach a capturing square?
+						// Easy but quite suboptimal way (TODO): generate all moves (turn is OK)
+						const moves = this.getPotentialMovesFrom([i,j]);
+						for (let move of moves)
+						{
+							if (sameRow && move.end.y == y || sameColumn && move.end.x == x)
+								return true;
+						}
+					}
+				}
+			}
+		}
+		return false;
 	}
 
-	isAttackedByKnight(sq, colors)
+	isAttackedByKnight([x,y], colors)
 	{
 		// Square (x,y) must be on same line as a knight,
 		// and there must be empty square(s) behind.
+		const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		outerLoop:
+		for (let step of steps)
+		{
+			const [i0,j0] = [x+step[0],y+step[1]];
+			if (V.OnBoard(i0,j0) && this.board[i0][j0] == V.EMPTY)
+			{
+				// Try in opposite direction:
+				let [i,j] = [x-step[0],y-step[1]];
+				while (V.OnBoard(i,j))
+				{
+					while (V.OnBoard(i,j) && this.board[i][j] == V.EMPTY)
+					{
+						i -= step[0];
+						j -= step[1];
+					}
+					if (V.OnBoard(i,j))
+					{
+						if (colors.includes(this.getColor(i,j)))
+						{
+							if (this.getPiece(i,j) == V.KNIGHT && !this.isImmobilized([i,j]))
+								return true;
+							continue outerLoop;
+						}
+						// [else] Our color, could be captured *if there was an empty space*
+						if (this.board[i+step[0]][j+step[1]] != V.EMPTY)
+							continue outerLoop;
+						i -= step[0];
+						j -= step[1];
+					}
+				}
+			}
+		}
+		return false;
 	}
 
-	isAttackedByBishop(sq, colors)
+	isAttackedByBishop([x,y], colors)
 	{
-		// switch on piece nature on square sq: a chameleon attack as this piece
-		// ==> call the appropriate isAttackedBy... (exception of immobilizers)
-		// Other exception: a chameleon cannot attack a chameleon (seemingly...)
+		// We cheat a little here: since this function is used exclusively for king,
+		// it's enough to check the immediate surrounding of the square.
+		const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		for (let step of adjacentSteps)
+		{
+			const [i,j] = [x+step[0],y+step[1]];
+			if (V.OnBoard(i,j) && this.board[i][j]!=V.EMPTY
+				&& colors.includes(this.getColor(i,j)) && this.getPiece(i,j) == V.BISHOP)
+			{
+				return true; //bishops are never immobilized
+			}
+		}
+		return false;
 	}
 
-	isAttackedByQueen(sq, colors)
+	isAttackedByQueen([x,y], colors)
 	{
 		// Square (x,y) must be adjacent to a queen, and the queen must have
 		// some free space in the opposite direction from (x,y)
+		const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+		for (let step of adjacentSteps)
+		{
+			const sq2 = [x+2*step[0],y+2*step[1]];
+			if (V.OnBoard(sq2[0],sq2[1]) && this.board[sq2[0]][sq2[1]] == V.EMPTY)
+			{
+				const sq1 = [x+step[0],y+step[1]];
+				if (this.board[sq1[0]][sq1[1]] != V.EMPTY
+					&& colors.includes(this.getColor(sq1[0],sq1[1]))
+					&& this.getPiece(sq1[0],sq1[1]) == V.QUEEN
+					&& !this.isImmobilized(sq1))
+				{
+					return true;
+				}
+			}
+		}
+		return false;
 	}
 
 	updateVariables(move)
 	{
-		// Just update king position
+		// Just update king(s) position(s)
 		const piece = this.getPiece(move.start.x,move.start.y);
 		const c = this.getColor(move.start.x,move.start.y);
-		if (piece == VariantRules.KING && move.appear.length > 0)
+		if (piece == V.KING && move.appear.length > 0)
 		{
 			this.kingPos[c][0] = move.appear[0].x;
 			this.kingPos[c][1] = move.appear[0].y;
@@ -250,4 +615,24 @@ class UltimaRules extends ChessRules
 	{
 		return "0000"; //TODO: or "-" ?
 	}
+
+	getNotation(move)
+	{
+		const initialSquare =
+			String.fromCharCode(97 + move.start.y) + (V.size.x-move.start.x);
+		const finalSquare = String.fromCharCode(97 + move.end.y) + (V.size.x-move.end.x);
+		let notation = undefined;
+		if (move.appear[0].p == V.PAWN)
+		{
+			// Pawn: generally ambiguous short notation, so we use full description
+			notation = "P" + initialSquare + finalSquare;
+		}
+		else if (move.appear[0].p == V.KING)
+			notation = "K" + (move.vanish.length>1 ? "x" : "") + finalSquare;
+		else
+			notation = move.appear[0].p.toUpperCase() + finalSquare;
+		if (move.vanish.length > 1 && move.appear[0].p != V.KING)
+			notation += "X"; //capture mark (not describing what is captured...)
+		return notation;
+	}
 }