[vchess.git] / public / javascripts / variants / Grand.js

// NOTE: initial setup differs from the original; see
// https://www.chessvariants.com/large.dir/freeling.html
class GrandRules extends ChessRules
{
	static getPpath(b)
	{
		return ([V.MARSHALL,V.CARDINAL].includes(b[1]) ? "Grand/" : "") + b;
	}

	static IsGoodFen(fen)
	{
		if (!ChessRules.IsGoodFen(fen))
			return false;
		const fenParsed = V.ParseFen(fen);
		// 5) Check captures
		if (!fenParsed.captured || !fenParsed.captured.match(/^[0-9]{10,10}$/))
			return false;
		return true;
	}

	static GenRandInitFen()
	{
		const fen = ChessRules.GenRandInitFen();
		return fen.replace(" w 1111", " w 1111 0000000000");
	}

	getFen()
	{
		return super.getFen() + " " + this.getCapturedFen();
	}

	getCapturedFen()
	{
		let counts = _.map(_.range(10), 0);
		for (let i=0; i<V.PIECES.length; i++)
		{
			counts[i] = this.captured["w"][V.PIECES[i]];
			counts[5+i] = this.captured["b"][V.PIECES[i]];
		}
		return counts.join("");
	}

	setOtherVariables(fen)
	{
		super.setOtherVariables(fen);
		const fenParsed = V.ParseFen(fen);
		// Initialize captured pieces' counts from FEN
		this.captured =
		{
			"w":
			{
				[V.PAWN]: parseInt(fenParsed.captured[0]),
				[V.ROOK]: parseInt(fenParsed.captured[1]),
				[V.KNIGHT]: parseInt(fenParsed.captured[2]),
				[V.BISHOP]: parseInt(fenParsed.captured[3]),
				[V.QUEEN]: parseInt(fenParsed.captured[4]),
			},
			"b":
			{
				[V.PAWN]: parseInt(fenParsed.captured[5]),
				[V.ROOK]: parseInt(fenParsed.captured[6]),
				[V.KNIGHT]: parseInt(fenParsed.captured[7]),
				[V.BISHOP]: parseInt(fenParsed.captured[8]),
				[V.QUEEN]: parseInt(fenParsed.captured[9]),
			}
		};
	}

	static get size() { return {x:10,y:10}; }

	static get MARSHALL() { return 'm'; } //rook+knight
	static get CARDINAL() { return 'c'; } //bishop+knight

	static get PIECES()
	{
		return ChessRules.PIECES.concat([V.MARSHALL,V.CARDINAL]);
	}

	// There may be 2 enPassant squares (if pawn jump 3 squares)
	getEnpassantFen()
	{
		const L = this.epSquares.length;
		if (!this.epSquares[L-1])
			return "-"; //no en-passant
		let res = "";
		this.epSquares[L-1].forEach(sq => {
			res += V.CoordsToSquare(sq) + ",";
		});
		return res.slice(0,-1); //remove last comma
	}

	// En-passant after 2-sq or 3-sq jumps
	getEpSquare(moveOrSquare)
	{
		if (!moveOrSquare)
			return undefined;
		if (typeof moveOrSquare === "string")
		{
			const square = moveOrSquare;
			if (square == "-")
				return undefined;
			let res = [];
			square.split(",").forEach(sq => {
				res.push(V.SquareToCoords(sq));
			});
			return res;
		}
		// Argument is a move:
		const move = moveOrSquare;
		const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x];
		if (this.getPiece(sx,sy) == V.PAWN && Math.abs(sx - ex) >= 2)
		{
			const step = (ex-sx) / Math.abs(ex-sx);
			let res = [{
				x: sx + step,
				y: sy
			}];
			if (sx + 2*step != ex) //3-squares move
			{
				res.push({
					x: sx + 2*step,
					y: sy
				});
			}
			return res;
		}
		return undefined; //default
	}

	getPotentialMovesFrom([x,y])
	{
		switch (this.getPiece(x,y))
		{
			case V.MARSHALL:
				return this.getPotentialMarshallMoves([x,y]);
			case V.CARDINAL:
				return this.getPotentialCardinalMoves([x,y]);
			default:
				return super.getPotentialMovesFrom([x,y])
		}
	}

	// Special pawn rules: promotions to captured friendly pieces,
	// optional on ranks 8-9 and mandatory on rank 10.
	getPotentialPawnMoves([x,y])
	{
		const color = this.turn;
		let moves = [];
		const [sizeX,sizeY] = [V.size.x,V.size.y];
		const shift = (color == "w" ? -1 : 1);
		const startRanks = (color == "w" ? [sizeX-2,sizeX-3] : [1,2]);
		const lastRanks = (color == "w" ? [0,1,2] : [sizeX-1,sizeX-2,sizeX-3]);

		if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRanks[0])
		{
			// Normal moves
			if (this.board[x+shift][y] == V.EMPTY)
			{
				moves.push(this.getBasicMove([x,y], [x+shift,y]));
				if (startRanks.includes(x) && this.board[x+2*shift][y] == V.EMPTY)
				{
					// Two squares jump
					moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
					if (x == startRanks[0] && this.board[x+3*shift][y] == V.EMPTY)
					{
						// 3-squares jump
						moves.push(this.getBasicMove([x,y], [x+3*shift,y]));
					}
				}
			}
			// 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]));
			}
			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]));
			}
		}

		if (lastRanks.includes(x+shift))
		{
			// Promotion
			let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN,V.MARSHALL,V.CARDINAL];
			promotionPieces.forEach(p => {
				if (this.captured[color][p]==0)
					return;
				// Normal move
				if (this.board[x+shift][y] == V.EMPTY)
					moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,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}));
				}
				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}));
				}
			});
		}

		// En passant
		const Lep = this.epSquares.length;
		const epSquare = Lep>0 ? this.epSquares[Lep-1] : undefined;
		if (!!epSquare)
		{
			for (let epsq of epSquare)
			{
				// TODO: some redundant checks
				if (epsq.x == x+shift && Math.abs(epsq.y - y) == 1)
				{
					let epStep = epsq.y - y;
					var enpassantMove = this.getBasicMove([x,y], [x+shift,y+epStep]);
					enpassantMove.vanish.push({
						x: x,
						y: y+epStep,
						p: 'p',
						c: this.getColor(x,y+epStep)
					});
					moves.push(enpassantMove);
				}
			}
		}

		return moves;
	}

	// TODO: different castle?

	getPotentialMarshallMoves(sq)
	{
		return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]).concat(
			this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
	}

	getPotentialCardinalMoves(sq)
	{
		return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]).concat(
			this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
	}

	isAttacked(sq, colors)
	{
		return super.isAttacked(sq, colors)
			|| this.isAttackedByMarshall(sq, colors)
			|| this.isAttackedByCardinal(sq, colors);
	}

	isAttackedByMarshall(sq, colors)
	{
		return this.isAttackedBySlideNJump(sq, colors, V.MARSHALL, V.steps[V.ROOK])
			|| this.isAttackedBySlideNJump(
				sq, colors, V.MARSHALL, V.steps[V.KNIGHT], "oneStep");
	}

	isAttackedByCardinal(sq, colors)
	{
		return this.isAttackedBySlideNJump(sq, colors, V.CARDINAL, V.steps[V.BISHOP])
			|| this.isAttackedBySlideNJump(
				sq, colors, V.CARDINAL, V.steps[V.KNIGHT], "oneStep");
	}

	updateVariables(move)
	{
		super.updateVariables(move);
		if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
		{
			// Capture: update this.captured
			this.captured[move.vanish[1].c][move.vanish[1].p]++;
		}
	}

	unupdateVariables(move)
	{
		super.unupdateVariables(move);
		if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
			this.captured[move.vanish[1].c][move.vanish[1].p]--;
	}

	static get VALUES()
	{
		return Object.assign(
			ChessRules.VALUES,
			{'c': 5, 'm': 7} //experimental
		);
	}

	static get SEARCH_DEPTH() { return 2; }

	// TODO: this function could be generalized and shared better (how ?!...)
	static GenRandInitFen()
	{
		let pieces = { "w": new Array(10), "b": new Array(10) };
		// Shuffle pieces on first and last rank
		for (let c of ["w","b"])
		{
			let positions = _.range(10);

			// Get random squares for bishops
			let randIndex = 2 * _.random(4);
			let bishop1Pos = positions[randIndex];
			// The second bishop must be on a square of different color
			let randIndex_tmp = 2 * _.random(4) + 1;
			let bishop2Pos = positions[randIndex_tmp];
			// Remove chosen squares
			positions.splice(Math.max(randIndex,randIndex_tmp), 1);
			positions.splice(Math.min(randIndex,randIndex_tmp), 1);

			// Get random squares for knights
			randIndex = _.random(7);
			let knight1Pos = positions[randIndex];
			positions.splice(randIndex, 1);
			randIndex = _.random(6);
			let knight2Pos = positions[randIndex];
			positions.splice(randIndex, 1);

			// Get random square for queen
			randIndex = _.random(5);
			let queenPos = positions[randIndex];
			positions.splice(randIndex, 1);

			// ...random square for marshall
			randIndex = _.random(4);
			let marshallPos = positions[randIndex];
			positions.splice(randIndex, 1);

			// ...random square for cardinal
			randIndex = _.random(3);
			let cardinalPos = positions[randIndex];
			positions.splice(randIndex, 1);

			// Rooks and king positions are now fixed, because of the ordering rook-king-rook
			let rook1Pos = positions[0];
			let kingPos = positions[1];
			let rook2Pos = positions[2];

			// Finally put the shuffled pieces in the board array
			pieces[c][rook1Pos] = 'r';
			pieces[c][knight1Pos] = 'n';
			pieces[c][bishop1Pos] = 'b';
			pieces[c][queenPos] = 'q';
			pieces[c][marshallPos] = 'm';
			pieces[c][cardinalPos] = 'c';
			pieces[c][kingPos] = 'k';
			pieces[c][bishop2Pos] = 'b';
			pieces[c][knight2Pos] = 'n';
			pieces[c][rook2Pos] = 'r';
		}
		return pieces["b"].join("") +
			"/pppppppppp/10/10/10/10/10/10/PPPPPPPPPP/" +
			pieces["w"].join("").toUpperCase() +
			" w 1111 -";
	}
}
Commit	Line	Data
92342261 BA	1	// NOTE: initial setup differs from the original; see
92342261 BA	2	// https://www.chessvariants.com/large.dir/freeling.html
a37076f1 BA	3	class GrandRules extends ChessRules
	4	{
	5	static getPpath(b)
	6	{
c6052161	7	return ([V.MARSHALL,V.CARDINAL].includes(b[1]) ? "Grand/" : "") + b;
a37076f1 BA	8	}
a37076f1 BA	9
2d7194bd	10	static IsGoodFen(fen)
c6052161	11	{
2d7194bd BA	12	if (!ChessRules.IsGoodFen(fen))
	13	return false;
	14	const fenParsed = V.ParseFen(fen);
	15	// 5) Check captures
	16	if (!fenParsed.captured \|\| !fenParsed.captured.match(/^[0-9]{10,10}$/))
	17	return false;
	18	return true;
	19	}
	20
	21	static GenRandInitFen()
	22	{
	23	const fen = ChessRules.GenRandInitFen();
	24	return fen.replace(" w 1111", " w 1111 0000000000");
	25	}
	26
	27	getFen()
	28	{
	29	return super.getFen() + " " + this.getCapturedFen();
	30	}
	31
	32	getCapturedFen()
	33	{
	34	let counts = _.map(_.range(10), 0);
	35	for (let i=0; i<V.PIECES.length; i++)
	36	{
	37	counts[i] = this.captured["w"][V.PIECES[i]];
	38	counts[5+i] = this.captured["b"][V.PIECES[i]];
	39	}
	40	return counts.join("");
	41	}
	42
	43	setOtherVariables(fen)
	44	{
	45	super.setOtherVariables(fen);
	46	const fenParsed = V.ParseFen(fen);
	47	// Initialize captured pieces' counts from FEN
	48	this.captured =
	49	{
	50	"w":
	51	{
	52	[V.PAWN]: parseInt(fenParsed.captured[0]),
	53	[V.ROOK]: parseInt(fenParsed.captured[1]),
	54	[V.KNIGHT]: parseInt(fenParsed.captured[2]),
	55	[V.BISHOP]: parseInt(fenParsed.captured[3]),
	56	[V.QUEEN]: parseInt(fenParsed.captured[4]),
	57	},
	58	"b":
	59	{
	60	[V.PAWN]: parseInt(fenParsed.captured[5]),
	61	[V.ROOK]: parseInt(fenParsed.captured[6]),
	62	[V.KNIGHT]: parseInt(fenParsed.captured[7]),
	63	[V.BISHOP]: parseInt(fenParsed.captured[8]),
	64	[V.QUEEN]: parseInt(fenParsed.captured[9]),
	65	}
	66	};
c6052161 BA	67	}
c6052161 BA	68
0b7d99ec	69	static get size() { return {x:10,y:10}; }
c6052161	70
a37076f1 BA	71	static get MARSHALL() { return 'm'; } //rook+knight
	72	static get CARDINAL() { return 'c'; } //bishop+knight
	73
2d7194bd BA	74	static get PIECES()
2d7194bd BA	75	{
7931e479 BA	76	return ChessRules.PIECES.concat([V.MARSHALL,V.CARDINAL]);
	77	}
	78
2d7194bd BA	79	// There may be 2 enPassant squares (if pawn jump 3 squares)
	80	getEnpassantFen()
	81	{
	82	const L = this.epSquares.length;
	83	if (!this.epSquares[L-1])
	84	return "-"; //no en-passant
	85	let res = "";
	86	this.epSquares[L-1].forEach(sq => {
	87	res += V.CoordsToSquare(sq) + ",";
	88	});
	89	return res.slice(0,-1); //remove last comma
	90	}
	91
c6052161	92	// En-passant after 2-sq or 3-sq jumps
2d7194bd	93	getEpSquare(moveOrSquare)
a37076f1	94	{
2d7194bd BA	95	if (!moveOrSquare)
	96	return undefined;
	97	if (typeof moveOrSquare === "string")
	98	{
	99	const square = moveOrSquare;
	100	if (square == "-")
	101	return undefined;
	102	let res = [];
	103	square.split(",").forEach(sq => {
	104	res.push(V.SquareToCoords(sq));
	105	});
	106	return res;
	107	}
	108	// Argument is a move:
	109	const move = moveOrSquare;
a37076f1	110	const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x];
0b7d99ec	111	if (this.getPiece(sx,sy) == V.PAWN && Math.abs(sx - ex) >= 2)
a37076f1	112	{
c6052161 BA	113	const step = (ex-sx) / Math.abs(ex-sx);
	114	let res = [{
	115	x: sx + step,
a37076f1	116	y: sy
c6052161 BA	117	}];
	118	if (sx + 2*step != ex) //3-squares move
	119	{
	120	res.push({
	121	x: sx + 2*step,
	122	y: sy
	123	});
	124	}
	125	return res;
a37076f1 BA	126	}
	127	return undefined; //default
	128	}
	129
	130	getPotentialMovesFrom([x,y])
	131	{
	132	switch (this.getPiece(x,y))
	133	{
0b7d99ec	134	case V.MARSHALL:
a37076f1	135	return this.getPotentialMarshallMoves([x,y]);
0b7d99ec	136	case V.CARDINAL:
a37076f1 BA	137	return this.getPotentialCardinalMoves([x,y]);
	138	default:
	139	return super.getPotentialMovesFrom([x,y])
	140	}
	141	}
	142
c6052161 BA	143	// Special pawn rules: promotions to captured friendly pieces,
c6052161 BA	144	// optional on ranks 8-9 and mandatory on rank 10.
a37076f1 BA	145	getPotentialPawnMoves([x,y])
a37076f1 BA	146	{
c6052161 BA	147	const color = this.turn;
c6052161 BA	148	let moves = [];
0b7d99ec	149	const [sizeX,sizeY] = [V.size.x,V.size.y];
c6052161	150	const shift = (color == "w" ? -1 : 1);
cf130369 BA	151	const startRanks = (color == "w" ? [sizeX-2,sizeX-3] : [1,2]);
cf130369 BA	152	const lastRanks = (color == "w" ? [0,1,2] : [sizeX-1,sizeX-2,sizeX-3]);
c6052161 BA	153
	154	if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRanks[0])
	155	{
	156	// Normal moves
	157	if (this.board[x+shift][y] == V.EMPTY)
	158	{
	159	moves.push(this.getBasicMove([x,y], [x+shift,y]));
	160	if (startRanks.includes(x) && this.board[x+2*shift][y] == V.EMPTY)
	161	{
	162	// Two squares jump
	163	moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
8a196305	164	if (x == startRanks[0] && this.board[x+3*shift][y] == V.EMPTY)
c6052161 BA	165	{
	166	// 3-squares jump
	167	moves.push(this.getBasicMove([x,y], [x+3*shift,y]));
	168	}
	169	}
	170	}
	171	// Captures
92342261 BA	172	if (y>0 && this.canTake([x,y], [x+shift,y-1])
	173	&& this.board[x+shift][y-1] != V.EMPTY)
	174	{
c6052161	175	moves.push(this.getBasicMove([x,y], [x+shift,y-1]));
92342261 BA	176	}
	177	if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
	178	&& this.board[x+shift][y+1] != V.EMPTY)
	179	{
c6052161	180	moves.push(this.getBasicMove([x,y], [x+shift,y+1]));
92342261	181	}
c6052161 BA	182	}
	183
	184	if (lastRanks.includes(x+shift))
	185	{
	186	// Promotion
8a196305	187	let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN,V.MARSHALL,V.CARDINAL];
c6052161	188	promotionPieces.forEach(p => {
2d7194bd	189	if (this.captured[color][p]==0)
c6052161 BA	190	return;
	191	// Normal move
	192	if (this.board[x+shift][y] == V.EMPTY)
	193	moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,p:p}));
	194	// Captures
92342261 BA	195	if (y>0 && this.canTake([x,y], [x+shift,y-1])
	196	&& this.board[x+shift][y-1] != V.EMPTY)
	197	{
c6052161	198	moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:color,p:p}));
92342261 BA	199	}
	200	if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
	201	&& this.board[x+shift][y+1] != V.EMPTY)
	202	{
c6052161	203	moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:color,p:p}));
92342261	204	}
c6052161 BA	205	});
	206	}
	207
	208	// En passant
	209	const Lep = this.epSquares.length;
	210	const epSquare = Lep>0 ? this.epSquares[Lep-1] : undefined;
	211	if (!!epSquare)
	212	{
	213	for (let epsq of epSquare)
	214	{
	215	// TODO: some redundant checks
	216	if (epsq.x == x+shift && Math.abs(epsq.y - y) == 1)
	217	{
	218	let epStep = epsq.y - y;
	219	var enpassantMove = this.getBasicMove([x,y], [x+shift,y+epStep]);
	220	enpassantMove.vanish.push({
	221	x: x,
	222	y: y+epStep,
	223	p: 'p',
	224	c: this.getColor(x,y+epStep)
	225	});
	226	moves.push(enpassantMove);
	227	}
	228	}
	229	}
	230
	231	return moves;
a37076f1 BA	232	}
a37076f1 BA	233
8a196305 BA	234	// TODO: different castle?
8a196305 BA	235
a37076f1 BA	236	getPotentialMarshallMoves(sq)
a37076f1 BA	237	{
a37076f1 BA	238	return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]).concat(
	239	this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
	240	}
	241
	242	getPotentialCardinalMoves(sq)
	243	{
a37076f1 BA	244	return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]).concat(
	245	this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
	246	}
	247
	248	isAttacked(sq, colors)
	249	{
c6052161	250	return super.isAttacked(sq, colors)
a37076f1 BA	251	\|\| this.isAttackedByMarshall(sq, colors)
	252	\|\| this.isAttackedByCardinal(sq, colors);
	253	}
	254
	255	isAttackedByMarshall(sq, colors)
	256	{
a37076f1	257	return this.isAttackedBySlideNJump(sq, colors, V.MARSHALL, V.steps[V.ROOK])
92342261 BA	258	\|\| this.isAttackedBySlideNJump(
92342261 BA	259	sq, colors, V.MARSHALL, V.steps[V.KNIGHT], "oneStep");
a37076f1 BA	260	}
	261
	262	isAttackedByCardinal(sq, colors)
	263	{
a37076f1	264	return this.isAttackedBySlideNJump(sq, colors, V.CARDINAL, V.steps[V.BISHOP])
92342261 BA	265	\|\| this.isAttackedBySlideNJump(
92342261 BA	266	sq, colors, V.CARDINAL, V.steps[V.KNIGHT], "oneStep");
a37076f1 BA	267	}
a37076f1 BA	268
a6abf094	269	updateVariables(move)
c6052161	270	{
a6abf094	271	super.updateVariables(move);
0b7d99ec	272	if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
c6052161	273	{
2d7194bd BA	274	// Capture: update this.captured
2d7194bd BA	275	this.captured[move.vanish[1].c][move.vanish[1].p]++;
c6052161 BA	276	}
	277	}
	278
a6abf094	279	unupdateVariables(move)
c6052161	280	{
a6abf094	281	super.unupdateVariables(move);
0b7d99ec	282	if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
2d7194bd	283	this.captured[move.vanish[1].c][move.vanish[1].p]--;
c6052161 BA	284	}
c6052161 BA	285
2d7194bd BA	286	static get VALUES()
2d7194bd BA	287	{
a37076f1 BA	288	return Object.assign(
	289	ChessRules.VALUES,
	290	{'c': 5, 'm': 7} //experimental
	291	);
	292	}
	293
3c09dc49 BA	294	static get SEARCH_DEPTH() { return 2; }
3c09dc49 BA	295
2d7194bd	296	// TODO: this function could be generalized and shared better (how ?!...)
a37076f1 BA	297	static GenRandInitFen()
a37076f1 BA	298	{
92342261	299	let pieces = { "w": new Array(10), "b": new Array(10) };
c6052161	300	// Shuffle pieces on first and last rank
92342261	301	for (let c of ["w","b"])
c6052161 BA	302	{
	303	let positions = _.range(10);
	304
	305	// Get random squares for bishops
	306	let randIndex = 2 * _.random(4);
	307	let bishop1Pos = positions[randIndex];
	308	// The second bishop must be on a square of different color
	309	let randIndex_tmp = 2 * _.random(4) + 1;
	310	let bishop2Pos = positions[randIndex_tmp];
	311	// Remove chosen squares
	312	positions.splice(Math.max(randIndex,randIndex_tmp), 1);
	313	positions.splice(Math.min(randIndex,randIndex_tmp), 1);
	314
	315	// Get random squares for knights
	316	randIndex = _.random(7);
	317	let knight1Pos = positions[randIndex];
	318	positions.splice(randIndex, 1);
	319	randIndex = _.random(6);
	320	let knight2Pos = positions[randIndex];
	321	positions.splice(randIndex, 1);
	322
	323	// Get random square for queen
	324	randIndex = _.random(5);
	325	let queenPos = positions[randIndex];
	326	positions.splice(randIndex, 1);
	327
	328	// ...random square for marshall
	329	randIndex = _.random(4);
	330	let marshallPos = positions[randIndex];
	331	positions.splice(randIndex, 1);
	332
	333	// ...random square for cardinal
	334	randIndex = _.random(3);
	335	let cardinalPos = positions[randIndex];
	336	positions.splice(randIndex, 1);
	337
	338	// Rooks and king positions are now fixed, because of the ordering rook-king-rook
	339	let rook1Pos = positions[0];
	340	let kingPos = positions[1];
	341	let rook2Pos = positions[2];
	342
	343	// Finally put the shuffled pieces in the board array
	344	pieces[c][rook1Pos] = 'r';
	345	pieces[c][knight1Pos] = 'n';
	346	pieces[c][bishop1Pos] = 'b';
	347	pieces[c][queenPos] = 'q';
	348	pieces[c][marshallPos] = 'm';
	349	pieces[c][cardinalPos] = 'c';
	350	pieces[c][kingPos] = 'k';
	351	pieces[c][bishop2Pos] = 'b';
	352	pieces[c][knight2Pos] = 'n';
	353	pieces[c][rook2Pos] = 'r';
	354	}
c794dbb8	355	return pieces["b"].join("") +
c6052161	356	"/pppppppppp/10/10/10/10/10/10/PPPPPPPPPP/" +
92342261	357	pieces["w"].join("").toUpperCase() +
2d7194bd	358	" w 1111 -";
a37076f1 BA	359	}
a37076f1 BA	360	}