3384 lines
105 KiB
JavaScript
3384 lines
105 KiB
JavaScript
'use strict';
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// @generated by Peggy 4.2.0.
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//
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// https://peggyjs.org/
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function rootNode(comment) {
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return comment !== null ? { comment, variations: [] } : { variations: []}
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}
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function node(move, suffix, nag, comment, variations) {
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const node = { move, variations };
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if (suffix) {
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node.suffix = suffix;
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}
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if (nag) {
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node.nag = nag;
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}
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if (comment !== null) {
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node.comment = comment;
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}
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return node
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}
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function lineToTree(...nodes) {
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const [root, ...rest] = nodes;
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let parent = root;
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for (const child of rest) {
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if (child !== null) {
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parent.variations = [child, ...child.variations];
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child.variations = [];
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parent = child;
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}
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}
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return root
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}
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function pgn(headers, game) {
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if (game.marker && game.marker.comment) {
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let node = game.root;
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while (true) {
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const next = node.variations[0];
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if (!next) {
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node.comment = game.marker.comment;
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break
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}
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node = next;
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}
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}
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return {
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headers,
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root: game.root,
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result: (game.marker && game.marker.result) ?? undefined
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}
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}
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function peg$subclass(child, parent) {
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function C() { this.constructor = child; }
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C.prototype = parent.prototype;
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child.prototype = new C();
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}
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function peg$SyntaxError(message, expected, found, location) {
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var self = Error.call(this, message);
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// istanbul ignore next Check is a necessary evil to support older environments
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if (Object.setPrototypeOf) {
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Object.setPrototypeOf(self, peg$SyntaxError.prototype);
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}
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self.expected = expected;
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self.found = found;
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self.location = location;
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self.name = "SyntaxError";
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return self;
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}
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peg$subclass(peg$SyntaxError, Error);
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function peg$padEnd(str, targetLength, padString) {
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padString = padString || " ";
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if (str.length > targetLength) { return str; }
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targetLength -= str.length;
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padString += padString.repeat(targetLength);
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return str + padString.slice(0, targetLength);
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}
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peg$SyntaxError.prototype.format = function(sources) {
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var str = "Error: " + this.message;
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if (this.location) {
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var src = null;
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var k;
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for (k = 0; k < sources.length; k++) {
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if (sources[k].source === this.location.source) {
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src = sources[k].text.split(/\r\n|\n|\r/g);
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break;
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}
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}
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var s = this.location.start;
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var offset_s = (this.location.source && (typeof this.location.source.offset === "function"))
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? this.location.source.offset(s)
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: s;
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var loc = this.location.source + ":" + offset_s.line + ":" + offset_s.column;
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if (src) {
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var e = this.location.end;
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var filler = peg$padEnd("", offset_s.line.toString().length, ' ');
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var line = src[s.line - 1];
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var last = s.line === e.line ? e.column : line.length + 1;
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var hatLen = (last - s.column) || 1;
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str += "\n --> " + loc + "\n"
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+ filler + " |\n"
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+ offset_s.line + " | " + line + "\n"
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+ filler + " | " + peg$padEnd("", s.column - 1, ' ')
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+ peg$padEnd("", hatLen, "^");
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} else {
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str += "\n at " + loc;
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}
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}
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return str;
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};
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peg$SyntaxError.buildMessage = function(expected, found) {
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var DESCRIBE_EXPECTATION_FNS = {
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literal: function(expectation) {
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return "\"" + literalEscape(expectation.text) + "\"";
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},
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class: function(expectation) {
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var escapedParts = expectation.parts.map(function(part) {
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return Array.isArray(part)
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? classEscape(part[0]) + "-" + classEscape(part[1])
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: classEscape(part);
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});
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return "[" + (expectation.inverted ? "^" : "") + escapedParts.join("") + "]";
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},
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any: function() {
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return "any character";
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},
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end: function() {
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return "end of input";
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},
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other: function(expectation) {
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return expectation.description;
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}
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};
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function hex(ch) {
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return ch.charCodeAt(0).toString(16).toUpperCase();
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}
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function literalEscape(s) {
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return s
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.replace(/\\/g, "\\\\")
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.replace(/"/g, "\\\"")
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.replace(/\0/g, "\\0")
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.replace(/\t/g, "\\t")
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.replace(/\n/g, "\\n")
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.replace(/\r/g, "\\r")
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.replace(/[\x00-\x0F]/g, function(ch) { return "\\x0" + hex(ch); })
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.replace(/[\x10-\x1F\x7F-\x9F]/g, function(ch) { return "\\x" + hex(ch); });
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}
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function classEscape(s) {
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return s
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.replace(/\\/g, "\\\\")
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.replace(/\]/g, "\\]")
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.replace(/\^/g, "\\^")
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.replace(/-/g, "\\-")
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.replace(/\0/g, "\\0")
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.replace(/\t/g, "\\t")
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.replace(/\n/g, "\\n")
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.replace(/\r/g, "\\r")
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.replace(/[\x00-\x0F]/g, function(ch) { return "\\x0" + hex(ch); })
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.replace(/[\x10-\x1F\x7F-\x9F]/g, function(ch) { return "\\x" + hex(ch); });
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}
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function describeExpectation(expectation) {
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return DESCRIBE_EXPECTATION_FNS[expectation.type](expectation);
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}
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function describeExpected(expected) {
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var descriptions = expected.map(describeExpectation);
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var i, j;
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descriptions.sort();
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if (descriptions.length > 0) {
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for (i = 1, j = 1; i < descriptions.length; i++) {
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if (descriptions[i - 1] !== descriptions[i]) {
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descriptions[j] = descriptions[i];
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j++;
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}
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}
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descriptions.length = j;
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}
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switch (descriptions.length) {
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case 1:
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return descriptions[0];
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case 2:
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return descriptions[0] + " or " + descriptions[1];
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default:
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return descriptions.slice(0, -1).join(", ")
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+ ", or "
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+ descriptions[descriptions.length - 1];
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}
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}
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function describeFound(found) {
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return found ? "\"" + literalEscape(found) + "\"" : "end of input";
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}
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return "Expected " + describeExpected(expected) + " but " + describeFound(found) + " found.";
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};
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function peg$parse(input, options) {
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options = options !== undefined ? options : {};
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var peg$FAILED = {};
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var peg$source = options.grammarSource;
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var peg$startRuleFunctions = { pgn: peg$parsepgn };
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var peg$startRuleFunction = peg$parsepgn;
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var peg$c0 = "[";
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var peg$c1 = "\"";
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var peg$c2 = "]";
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var peg$c3 = ".";
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var peg$c4 = "O-O-O";
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var peg$c5 = "O-O";
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var peg$c6 = "0-0-0";
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var peg$c7 = "0-0";
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var peg$c8 = "$";
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var peg$c9 = "{";
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var peg$c10 = "}";
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var peg$c11 = ";";
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var peg$c12 = "(";
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var peg$c13 = ")";
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var peg$c14 = "1-0";
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var peg$c15 = "0-1";
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var peg$c16 = "1/2-1/2";
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var peg$c17 = "*";
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var peg$r0 = /^[a-zA-Z]/;
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var peg$r1 = /^[^"]/;
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var peg$r2 = /^[0-9]/;
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var peg$r3 = /^[.]/;
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var peg$r4 = /^[a-zA-Z1-8\-=]/;
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var peg$r5 = /^[+#]/;
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var peg$r6 = /^[!?]/;
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var peg$r7 = /^[^}]/;
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var peg$r8 = /^[^\r\n]/;
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var peg$r9 = /^[ \t\r\n]/;
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var peg$e0 = peg$otherExpectation("tag pair");
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var peg$e1 = peg$literalExpectation("[", false);
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var peg$e2 = peg$literalExpectation("\"", false);
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var peg$e3 = peg$literalExpectation("]", false);
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var peg$e4 = peg$otherExpectation("tag name");
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var peg$e5 = peg$classExpectation([["a", "z"], ["A", "Z"]], false, false);
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var peg$e6 = peg$otherExpectation("tag value");
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var peg$e7 = peg$classExpectation(["\""], true, false);
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var peg$e8 = peg$otherExpectation("move number");
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var peg$e9 = peg$classExpectation([["0", "9"]], false, false);
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var peg$e10 = peg$literalExpectation(".", false);
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var peg$e11 = peg$classExpectation(["."], false, false);
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var peg$e12 = peg$otherExpectation("standard algebraic notation");
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var peg$e13 = peg$literalExpectation("O-O-O", false);
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var peg$e14 = peg$literalExpectation("O-O", false);
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var peg$e15 = peg$literalExpectation("0-0-0", false);
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var peg$e16 = peg$literalExpectation("0-0", false);
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var peg$e17 = peg$classExpectation([["a", "z"], ["A", "Z"], ["1", "8"], "-", "="], false, false);
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var peg$e18 = peg$classExpectation(["+", "#"], false, false);
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var peg$e19 = peg$otherExpectation("suffix annotation");
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var peg$e20 = peg$classExpectation(["!", "?"], false, false);
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var peg$e21 = peg$otherExpectation("NAG");
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var peg$e22 = peg$literalExpectation("$", false);
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var peg$e23 = peg$otherExpectation("brace comment");
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var peg$e24 = peg$literalExpectation("{", false);
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var peg$e25 = peg$classExpectation(["}"], true, false);
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var peg$e26 = peg$literalExpectation("}", false);
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var peg$e27 = peg$otherExpectation("rest of line comment");
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var peg$e28 = peg$literalExpectation(";", false);
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var peg$e29 = peg$classExpectation(["\r", "\n"], true, false);
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var peg$e30 = peg$otherExpectation("variation");
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var peg$e31 = peg$literalExpectation("(", false);
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var peg$e32 = peg$literalExpectation(")", false);
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var peg$e33 = peg$otherExpectation("game termination marker");
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var peg$e34 = peg$literalExpectation("1-0", false);
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var peg$e35 = peg$literalExpectation("0-1", false);
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var peg$e36 = peg$literalExpectation("1/2-1/2", false);
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var peg$e37 = peg$literalExpectation("*", false);
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var peg$e38 = peg$otherExpectation("whitespace");
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var peg$e39 = peg$classExpectation([" ", "\t", "\r", "\n"], false, false);
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var peg$f0 = function(headers, game) { return pgn(headers, game) };
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var peg$f1 = function(tagPairs) { return Object.fromEntries(tagPairs) };
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var peg$f2 = function(tagName, tagValue) { return [tagName, tagValue] };
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var peg$f3 = function(root, marker) { return { root, marker} };
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var peg$f4 = function(comment, moves) { return lineToTree(rootNode(comment), ...moves.flat()) };
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var peg$f5 = function(san, suffix, nag, comment, variations) { return node(san, suffix, nag, comment, variations) };
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var peg$f6 = function(nag) { return nag };
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var peg$f7 = function(comment) { return comment.replace(/[\r\n]+/g, " ") };
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var peg$f8 = function(comment) { return comment.trim() };
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var peg$f9 = function(line) { return line };
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var peg$f10 = function(result, comment) { return { result, comment } };
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var peg$currPos = options.peg$currPos | 0;
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var peg$posDetailsCache = [{ line: 1, column: 1 }];
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var peg$maxFailPos = peg$currPos;
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var peg$maxFailExpected = options.peg$maxFailExpected || [];
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var peg$silentFails = options.peg$silentFails | 0;
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var peg$result;
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if (options.startRule) {
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if (!(options.startRule in peg$startRuleFunctions)) {
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throw new Error("Can't start parsing from rule \"" + options.startRule + "\".");
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}
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peg$startRuleFunction = peg$startRuleFunctions[options.startRule];
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}
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function peg$literalExpectation(text, ignoreCase) {
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return { type: "literal", text: text, ignoreCase: ignoreCase };
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}
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function peg$classExpectation(parts, inverted, ignoreCase) {
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return { type: "class", parts: parts, inverted: inverted, ignoreCase: ignoreCase };
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}
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function peg$endExpectation() {
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return { type: "end" };
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}
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function peg$otherExpectation(description) {
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return { type: "other", description: description };
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}
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function peg$computePosDetails(pos) {
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var details = peg$posDetailsCache[pos];
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var p;
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if (details) {
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return details;
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} else {
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if (pos >= peg$posDetailsCache.length) {
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p = peg$posDetailsCache.length - 1;
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} else {
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p = pos;
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while (!peg$posDetailsCache[--p]) {}
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}
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details = peg$posDetailsCache[p];
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details = {
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line: details.line,
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column: details.column
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};
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while (p < pos) {
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if (input.charCodeAt(p) === 10) {
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details.line++;
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details.column = 1;
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} else {
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details.column++;
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}
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p++;
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}
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peg$posDetailsCache[pos] = details;
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return details;
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}
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}
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function peg$computeLocation(startPos, endPos, offset) {
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var startPosDetails = peg$computePosDetails(startPos);
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var endPosDetails = peg$computePosDetails(endPos);
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var res = {
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source: peg$source,
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start: {
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offset: startPos,
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line: startPosDetails.line,
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column: startPosDetails.column
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},
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end: {
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offset: endPos,
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line: endPosDetails.line,
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column: endPosDetails.column
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}
|
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};
|
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return res;
|
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}
|
|
|
|
function peg$fail(expected) {
|
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if (peg$currPos < peg$maxFailPos) { return; }
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|
|
|
if (peg$currPos > peg$maxFailPos) {
|
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peg$maxFailPos = peg$currPos;
|
|
peg$maxFailExpected = [];
|
|
}
|
|
|
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peg$maxFailExpected.push(expected);
|
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}
|
|
|
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function peg$buildStructuredError(expected, found, location) {
|
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return new peg$SyntaxError(
|
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peg$SyntaxError.buildMessage(expected, found),
|
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expected,
|
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found,
|
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location
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);
|
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}
|
|
|
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function peg$parsepgn() {
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var s0, s1, s2;
|
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|
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s0 = peg$currPos;
|
|
s1 = peg$parsetagPairSection();
|
|
s2 = peg$parsemoveTextSection();
|
|
s0 = peg$f0(s1, s2);
|
|
|
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return s0;
|
|
}
|
|
|
|
function peg$parsetagPairSection() {
|
|
var s0, s1, s2;
|
|
|
|
s0 = peg$currPos;
|
|
s1 = [];
|
|
s2 = peg$parsetagPair();
|
|
while (s2 !== peg$FAILED) {
|
|
s1.push(s2);
|
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s2 = peg$parsetagPair();
|
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}
|
|
s2 = peg$parse_();
|
|
s0 = peg$f1(s1);
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsetagPair() {
|
|
var s0, s2, s4, s6, s7, s8, s10;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 91) {
|
|
s2 = peg$c0;
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e1); }
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
peg$parse_();
|
|
s4 = peg$parsetagName();
|
|
if (s4 !== peg$FAILED) {
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 34) {
|
|
s6 = peg$c1;
|
|
peg$currPos++;
|
|
} else {
|
|
s6 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e2); }
|
|
}
|
|
if (s6 !== peg$FAILED) {
|
|
s7 = peg$parsetagValue();
|
|
if (input.charCodeAt(peg$currPos) === 34) {
|
|
s8 = peg$c1;
|
|
peg$currPos++;
|
|
} else {
|
|
s8 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e2); }
|
|
}
|
|
if (s8 !== peg$FAILED) {
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 93) {
|
|
s10 = peg$c2;
|
|
peg$currPos++;
|
|
} else {
|
|
s10 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e3); }
|
|
}
|
|
if (s10 !== peg$FAILED) {
|
|
s0 = peg$f2(s4, s7);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
if (peg$silentFails === 0) { peg$fail(peg$e0); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsetagName() {
|
|
var s0, s1, s2;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
s1 = [];
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r0.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e5); }
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
while (s2 !== peg$FAILED) {
|
|
s1.push(s2);
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r0.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e5); }
|
|
}
|
|
}
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
}
|
|
if (s1 !== peg$FAILED) {
|
|
s0 = input.substring(s0, peg$currPos);
|
|
} else {
|
|
s0 = s1;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e4); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsetagValue() {
|
|
var s0, s1, s2;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
s1 = [];
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r1.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e7); }
|
|
}
|
|
while (s2 !== peg$FAILED) {
|
|
s1.push(s2);
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r1.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e7); }
|
|
}
|
|
}
|
|
s0 = input.substring(s0, peg$currPos);
|
|
peg$silentFails--;
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e6); }
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsemoveTextSection() {
|
|
var s0, s1, s3;
|
|
|
|
s0 = peg$currPos;
|
|
s1 = peg$parseline();
|
|
peg$parse_();
|
|
s3 = peg$parsegameTerminationMarker();
|
|
if (s3 === peg$FAILED) {
|
|
s3 = null;
|
|
}
|
|
peg$parse_();
|
|
s0 = peg$f3(s1, s3);
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parseline() {
|
|
var s0, s1, s2, s3;
|
|
|
|
s0 = peg$currPos;
|
|
s1 = peg$parsecomment();
|
|
if (s1 === peg$FAILED) {
|
|
s1 = null;
|
|
}
|
|
s2 = [];
|
|
s3 = peg$parsemove();
|
|
while (s3 !== peg$FAILED) {
|
|
s2.push(s3);
|
|
s3 = peg$parsemove();
|
|
}
|
|
s0 = peg$f4(s1, s2);
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsemove() {
|
|
var s0, s4, s5, s6, s7, s8, s9, s10;
|
|
|
|
s0 = peg$currPos;
|
|
peg$parse_();
|
|
peg$parsemoveNumber();
|
|
peg$parse_();
|
|
s4 = peg$parsesan();
|
|
if (s4 !== peg$FAILED) {
|
|
s5 = peg$parsesuffixAnnotation();
|
|
if (s5 === peg$FAILED) {
|
|
s5 = null;
|
|
}
|
|
s6 = [];
|
|
s7 = peg$parsenag();
|
|
while (s7 !== peg$FAILED) {
|
|
s6.push(s7);
|
|
s7 = peg$parsenag();
|
|
}
|
|
s7 = peg$parse_();
|
|
s8 = peg$parsecomment();
|
|
if (s8 === peg$FAILED) {
|
|
s8 = null;
|
|
}
|
|
s9 = [];
|
|
s10 = peg$parsevariation();
|
|
while (s10 !== peg$FAILED) {
|
|
s9.push(s10);
|
|
s10 = peg$parsevariation();
|
|
}
|
|
s0 = peg$f5(s4, s5, s6, s8, s9);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsemoveNumber() {
|
|
var s0, s1, s2, s3, s4, s5;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
s1 = [];
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r2.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e9); }
|
|
}
|
|
while (s2 !== peg$FAILED) {
|
|
s1.push(s2);
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r2.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e9); }
|
|
}
|
|
}
|
|
if (input.charCodeAt(peg$currPos) === 46) {
|
|
s2 = peg$c3;
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e10); }
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
s3 = peg$parse_();
|
|
s4 = [];
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r3.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e11); }
|
|
}
|
|
while (s5 !== peg$FAILED) {
|
|
s4.push(s5);
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r3.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e11); }
|
|
}
|
|
}
|
|
s1 = [s1, s2, s3, s4];
|
|
s0 = s1;
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e8); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsesan() {
|
|
var s0, s1, s2, s3, s4, s5;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
s1 = peg$currPos;
|
|
if (input.substr(peg$currPos, 5) === peg$c4) {
|
|
s2 = peg$c4;
|
|
peg$currPos += 5;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e13); }
|
|
}
|
|
if (s2 === peg$FAILED) {
|
|
if (input.substr(peg$currPos, 3) === peg$c5) {
|
|
s2 = peg$c5;
|
|
peg$currPos += 3;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e14); }
|
|
}
|
|
if (s2 === peg$FAILED) {
|
|
if (input.substr(peg$currPos, 5) === peg$c6) {
|
|
s2 = peg$c6;
|
|
peg$currPos += 5;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e15); }
|
|
}
|
|
if (s2 === peg$FAILED) {
|
|
if (input.substr(peg$currPos, 3) === peg$c7) {
|
|
s2 = peg$c7;
|
|
peg$currPos += 3;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e16); }
|
|
}
|
|
if (s2 === peg$FAILED) {
|
|
s2 = peg$currPos;
|
|
s3 = input.charAt(peg$currPos);
|
|
if (peg$r0.test(s3)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s3 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e5); }
|
|
}
|
|
if (s3 !== peg$FAILED) {
|
|
s4 = [];
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r4.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e17); }
|
|
}
|
|
if (s5 !== peg$FAILED) {
|
|
while (s5 !== peg$FAILED) {
|
|
s4.push(s5);
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r4.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e17); }
|
|
}
|
|
}
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
}
|
|
if (s4 !== peg$FAILED) {
|
|
s3 = [s3, s4];
|
|
s2 = s3;
|
|
} else {
|
|
peg$currPos = s2;
|
|
s2 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s2;
|
|
s2 = peg$FAILED;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
s3 = input.charAt(peg$currPos);
|
|
if (peg$r5.test(s3)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s3 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e18); }
|
|
}
|
|
if (s3 === peg$FAILED) {
|
|
s3 = null;
|
|
}
|
|
s2 = [s2, s3];
|
|
s1 = s2;
|
|
} else {
|
|
peg$currPos = s1;
|
|
s1 = peg$FAILED;
|
|
}
|
|
if (s1 !== peg$FAILED) {
|
|
s0 = input.substring(s0, peg$currPos);
|
|
} else {
|
|
s0 = s1;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e12); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsesuffixAnnotation() {
|
|
var s0, s1, s2;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
s1 = [];
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r6.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e20); }
|
|
}
|
|
while (s2 !== peg$FAILED) {
|
|
s1.push(s2);
|
|
if (s1.length >= 2) {
|
|
s2 = peg$FAILED;
|
|
} else {
|
|
s2 = input.charAt(peg$currPos);
|
|
if (peg$r6.test(s2)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e20); }
|
|
}
|
|
}
|
|
}
|
|
if (s1.length < 1) {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
} else {
|
|
s0 = s1;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e19); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsenag() {
|
|
var s0, s2, s3, s4, s5;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 36) {
|
|
s2 = peg$c8;
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e22); }
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
s3 = peg$currPos;
|
|
s4 = [];
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r2.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e9); }
|
|
}
|
|
if (s5 !== peg$FAILED) {
|
|
while (s5 !== peg$FAILED) {
|
|
s4.push(s5);
|
|
s5 = input.charAt(peg$currPos);
|
|
if (peg$r2.test(s5)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e9); }
|
|
}
|
|
}
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
}
|
|
if (s4 !== peg$FAILED) {
|
|
s3 = input.substring(s3, peg$currPos);
|
|
} else {
|
|
s3 = s4;
|
|
}
|
|
if (s3 !== peg$FAILED) {
|
|
s0 = peg$f6(s3);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
if (peg$silentFails === 0) { peg$fail(peg$e21); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsecomment() {
|
|
var s0;
|
|
|
|
s0 = peg$parsebraceComment();
|
|
if (s0 === peg$FAILED) {
|
|
s0 = peg$parserestOfLineComment();
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsebraceComment() {
|
|
var s0, s1, s2, s3, s4;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
if (input.charCodeAt(peg$currPos) === 123) {
|
|
s1 = peg$c9;
|
|
peg$currPos++;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e24); }
|
|
}
|
|
if (s1 !== peg$FAILED) {
|
|
s2 = peg$currPos;
|
|
s3 = [];
|
|
s4 = input.charAt(peg$currPos);
|
|
if (peg$r7.test(s4)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e25); }
|
|
}
|
|
while (s4 !== peg$FAILED) {
|
|
s3.push(s4);
|
|
s4 = input.charAt(peg$currPos);
|
|
if (peg$r7.test(s4)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e25); }
|
|
}
|
|
}
|
|
s2 = input.substring(s2, peg$currPos);
|
|
if (input.charCodeAt(peg$currPos) === 125) {
|
|
s3 = peg$c10;
|
|
peg$currPos++;
|
|
} else {
|
|
s3 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e26); }
|
|
}
|
|
if (s3 !== peg$FAILED) {
|
|
s0 = peg$f7(s2);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e23); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parserestOfLineComment() {
|
|
var s0, s1, s2, s3, s4;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
if (input.charCodeAt(peg$currPos) === 59) {
|
|
s1 = peg$c11;
|
|
peg$currPos++;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e28); }
|
|
}
|
|
if (s1 !== peg$FAILED) {
|
|
s2 = peg$currPos;
|
|
s3 = [];
|
|
s4 = input.charAt(peg$currPos);
|
|
if (peg$r8.test(s4)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e29); }
|
|
}
|
|
while (s4 !== peg$FAILED) {
|
|
s3.push(s4);
|
|
s4 = input.charAt(peg$currPos);
|
|
if (peg$r8.test(s4)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s4 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e29); }
|
|
}
|
|
}
|
|
s2 = input.substring(s2, peg$currPos);
|
|
s0 = peg$f8(s2);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e27); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsevariation() {
|
|
var s0, s2, s3, s5;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 40) {
|
|
s2 = peg$c12;
|
|
peg$currPos++;
|
|
} else {
|
|
s2 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e31); }
|
|
}
|
|
if (s2 !== peg$FAILED) {
|
|
s3 = peg$parseline();
|
|
if (s3 !== peg$FAILED) {
|
|
peg$parse_();
|
|
if (input.charCodeAt(peg$currPos) === 41) {
|
|
s5 = peg$c13;
|
|
peg$currPos++;
|
|
} else {
|
|
s5 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e32); }
|
|
}
|
|
if (s5 !== peg$FAILED) {
|
|
s0 = peg$f9(s3);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
if (peg$silentFails === 0) { peg$fail(peg$e30); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parsegameTerminationMarker() {
|
|
var s0, s1, s3;
|
|
|
|
peg$silentFails++;
|
|
s0 = peg$currPos;
|
|
if (input.substr(peg$currPos, 3) === peg$c14) {
|
|
s1 = peg$c14;
|
|
peg$currPos += 3;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e34); }
|
|
}
|
|
if (s1 === peg$FAILED) {
|
|
if (input.substr(peg$currPos, 3) === peg$c15) {
|
|
s1 = peg$c15;
|
|
peg$currPos += 3;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e35); }
|
|
}
|
|
if (s1 === peg$FAILED) {
|
|
if (input.substr(peg$currPos, 7) === peg$c16) {
|
|
s1 = peg$c16;
|
|
peg$currPos += 7;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e36); }
|
|
}
|
|
if (s1 === peg$FAILED) {
|
|
if (input.charCodeAt(peg$currPos) === 42) {
|
|
s1 = peg$c17;
|
|
peg$currPos++;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e37); }
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (s1 !== peg$FAILED) {
|
|
peg$parse_();
|
|
s3 = peg$parsecomment();
|
|
if (s3 === peg$FAILED) {
|
|
s3 = null;
|
|
}
|
|
s0 = peg$f10(s1, s3);
|
|
} else {
|
|
peg$currPos = s0;
|
|
s0 = peg$FAILED;
|
|
}
|
|
peg$silentFails--;
|
|
if (s0 === peg$FAILED) {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e33); }
|
|
}
|
|
|
|
return s0;
|
|
}
|
|
|
|
function peg$parse_() {
|
|
var s0, s1;
|
|
|
|
peg$silentFails++;
|
|
s0 = [];
|
|
s1 = input.charAt(peg$currPos);
|
|
if (peg$r9.test(s1)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e39); }
|
|
}
|
|
while (s1 !== peg$FAILED) {
|
|
s0.push(s1);
|
|
s1 = input.charAt(peg$currPos);
|
|
if (peg$r9.test(s1)) {
|
|
peg$currPos++;
|
|
} else {
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e39); }
|
|
}
|
|
}
|
|
peg$silentFails--;
|
|
s1 = peg$FAILED;
|
|
if (peg$silentFails === 0) { peg$fail(peg$e38); }
|
|
|
|
return s0;
|
|
}
|
|
|
|
peg$result = peg$startRuleFunction();
|
|
|
|
if (options.peg$library) {
|
|
return /** @type {any} */ ({
|
|
peg$result,
|
|
peg$currPos,
|
|
peg$FAILED,
|
|
peg$maxFailExpected,
|
|
peg$maxFailPos
|
|
});
|
|
}
|
|
if (peg$result !== peg$FAILED && peg$currPos === input.length) {
|
|
return peg$result;
|
|
} else {
|
|
if (peg$result !== peg$FAILED && peg$currPos < input.length) {
|
|
peg$fail(peg$endExpectation());
|
|
}
|
|
|
|
throw peg$buildStructuredError(
|
|
peg$maxFailExpected,
|
|
peg$maxFailPos < input.length ? input.charAt(peg$maxFailPos) : null,
|
|
peg$maxFailPos < input.length
|
|
? peg$computeLocation(peg$maxFailPos, peg$maxFailPos + 1)
|
|
: peg$computeLocation(peg$maxFailPos, peg$maxFailPos)
|
|
);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @license
|
|
* Copyright (c) 2025, Jeff Hlywa (jhlywa@gmail.com)
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice,
|
|
* this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
* this list of conditions and the following disclaimer in the documentation
|
|
* and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
const MASK64 = 0xffffffffffffffffn;
|
|
function rotl(x, k) {
|
|
return ((x << k) | (x >> (64n - k))) & 0xffffffffffffffffn;
|
|
}
|
|
function wrappingMul(x, y) {
|
|
return (x * y) & MASK64;
|
|
}
|
|
// xoroshiro128**
|
|
function xoroshiro128(state) {
|
|
return function () {
|
|
let s0 = BigInt(state & MASK64);
|
|
let s1 = BigInt((state >> 64n) & MASK64);
|
|
const result = wrappingMul(rotl(wrappingMul(s0, 5n), 7n), 9n);
|
|
s1 ^= s0;
|
|
s0 = (rotl(s0, 24n) ^ s1 ^ (s1 << 16n)) & MASK64;
|
|
s1 = rotl(s1, 37n);
|
|
state = (s1 << 64n) | s0;
|
|
return result;
|
|
};
|
|
}
|
|
const rand = xoroshiro128(0xa187eb39cdcaed8f31c4b365b102e01en);
|
|
const PIECE_KEYS = Array.from({ length: 2 }, () => Array.from({ length: 6 }, () => Array.from({ length: 128 }, () => rand())));
|
|
const EP_KEYS = Array.from({ length: 8 }, () => rand());
|
|
const CASTLING_KEYS = Array.from({ length: 16 }, () => rand());
|
|
const SIDE_KEY = rand();
|
|
const WHITE = 'w';
|
|
const BLACK = 'b';
|
|
const PAWN = 'p';
|
|
const KNIGHT = 'n';
|
|
const BISHOP = 'b';
|
|
const ROOK = 'r';
|
|
const QUEEN = 'q';
|
|
const KING = 'k';
|
|
const DEFAULT_POSITION = 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1';
|
|
class Move {
|
|
color;
|
|
from;
|
|
to;
|
|
piece;
|
|
captured;
|
|
promotion;
|
|
/**
|
|
* @deprecated This field is deprecated and will be removed in version 2.0.0.
|
|
* Please use move descriptor functions instead: `isCapture`, `isPromotion`,
|
|
* `isEnPassant`, `isKingsideCastle`, `isQueensideCastle`, `isCastle`, and
|
|
* `isBigPawn`
|
|
*/
|
|
flags;
|
|
san;
|
|
lan;
|
|
before;
|
|
after;
|
|
constructor(chess, internal) {
|
|
const { color, piece, from, to, flags, captured, promotion } = internal;
|
|
const fromAlgebraic = algebraic(from);
|
|
const toAlgebraic = algebraic(to);
|
|
this.color = color;
|
|
this.piece = piece;
|
|
this.from = fromAlgebraic;
|
|
this.to = toAlgebraic;
|
|
/*
|
|
* HACK: The chess['_method']() calls below invoke private methods in the
|
|
* Chess class to generate SAN and FEN. It's a bit of a hack, but makes the
|
|
* code cleaner elsewhere.
|
|
*/
|
|
this.san = chess['_moveToSan'](internal, chess['_moves']({ legal: true }));
|
|
this.lan = fromAlgebraic + toAlgebraic;
|
|
this.before = chess.fen();
|
|
// Generate the FEN for the 'after' key
|
|
chess['_makeMove'](internal);
|
|
this.after = chess.fen();
|
|
chess['_undoMove']();
|
|
// Build the text representation of the move flags
|
|
this.flags = '';
|
|
for (const flag in BITS) {
|
|
if (BITS[flag] & flags) {
|
|
this.flags += FLAGS[flag];
|
|
}
|
|
}
|
|
if (captured) {
|
|
this.captured = captured;
|
|
}
|
|
if (promotion) {
|
|
this.promotion = promotion;
|
|
this.lan += promotion;
|
|
}
|
|
}
|
|
isCapture() {
|
|
return this.flags.indexOf(FLAGS['CAPTURE']) > -1;
|
|
}
|
|
isPromotion() {
|
|
return this.flags.indexOf(FLAGS['PROMOTION']) > -1;
|
|
}
|
|
isEnPassant() {
|
|
return this.flags.indexOf(FLAGS['EP_CAPTURE']) > -1;
|
|
}
|
|
isKingsideCastle() {
|
|
return this.flags.indexOf(FLAGS['KSIDE_CASTLE']) > -1;
|
|
}
|
|
isQueensideCastle() {
|
|
return this.flags.indexOf(FLAGS['QSIDE_CASTLE']) > -1;
|
|
}
|
|
isBigPawn() {
|
|
return this.flags.indexOf(FLAGS['BIG_PAWN']) > -1;
|
|
}
|
|
}
|
|
const EMPTY = -1;
|
|
const FLAGS = {
|
|
NORMAL: 'n',
|
|
CAPTURE: 'c',
|
|
BIG_PAWN: 'b',
|
|
EP_CAPTURE: 'e',
|
|
PROMOTION: 'p',
|
|
KSIDE_CASTLE: 'k',
|
|
QSIDE_CASTLE: 'q',
|
|
NULL_MOVE: '-',
|
|
};
|
|
// prettier-ignore
|
|
const SQUARES = [
|
|
'a8', 'b8', 'c8', 'd8', 'e8', 'f8', 'g8', 'h8',
|
|
'a7', 'b7', 'c7', 'd7', 'e7', 'f7', 'g7', 'h7',
|
|
'a6', 'b6', 'c6', 'd6', 'e6', 'f6', 'g6', 'h6',
|
|
'a5', 'b5', 'c5', 'd5', 'e5', 'f5', 'g5', 'h5',
|
|
'a4', 'b4', 'c4', 'd4', 'e4', 'f4', 'g4', 'h4',
|
|
'a3', 'b3', 'c3', 'd3', 'e3', 'f3', 'g3', 'h3',
|
|
'a2', 'b2', 'c2', 'd2', 'e2', 'f2', 'g2', 'h2',
|
|
'a1', 'b1', 'c1', 'd1', 'e1', 'f1', 'g1', 'h1'
|
|
];
|
|
const BITS = {
|
|
NORMAL: 1,
|
|
CAPTURE: 2,
|
|
BIG_PAWN: 4,
|
|
EP_CAPTURE: 8,
|
|
PROMOTION: 16,
|
|
KSIDE_CASTLE: 32,
|
|
QSIDE_CASTLE: 64,
|
|
NULL_MOVE: 128,
|
|
};
|
|
/* eslint-disable @typescript-eslint/naming-convention */
|
|
// these are required, according to spec
|
|
const SEVEN_TAG_ROSTER = {
|
|
Event: '?',
|
|
Site: '?',
|
|
Date: '????.??.??',
|
|
Round: '?',
|
|
White: '?',
|
|
Black: '?',
|
|
Result: '*',
|
|
};
|
|
/**
|
|
* These nulls are placeholders to fix the order of tags (as they appear in PGN spec); null values will be
|
|
* eliminated in getHeaders()
|
|
*/
|
|
const SUPLEMENTAL_TAGS = {
|
|
WhiteTitle: null,
|
|
BlackTitle: null,
|
|
WhiteElo: null,
|
|
BlackElo: null,
|
|
WhiteUSCF: null,
|
|
BlackUSCF: null,
|
|
WhiteNA: null,
|
|
BlackNA: null,
|
|
WhiteType: null,
|
|
BlackType: null,
|
|
EventDate: null,
|
|
EventSponsor: null,
|
|
Section: null,
|
|
Stage: null,
|
|
Board: null,
|
|
Opening: null,
|
|
Variation: null,
|
|
SubVariation: null,
|
|
ECO: null,
|
|
NIC: null,
|
|
Time: null,
|
|
UTCTime: null,
|
|
UTCDate: null,
|
|
TimeControl: null,
|
|
SetUp: null,
|
|
FEN: null,
|
|
Termination: null,
|
|
Annotator: null,
|
|
Mode: null,
|
|
PlyCount: null,
|
|
};
|
|
const HEADER_TEMPLATE = {
|
|
...SEVEN_TAG_ROSTER,
|
|
...SUPLEMENTAL_TAGS,
|
|
};
|
|
/* eslint-enable @typescript-eslint/naming-convention */
|
|
/*
|
|
* NOTES ABOUT 0x88 MOVE GENERATION ALGORITHM
|
|
* ----------------------------------------------------------------------------
|
|
* From https://github.com/jhlywa/chess.js/issues/230
|
|
*
|
|
* A lot of people are confused when they first see the internal representation
|
|
* of chess.js. It uses the 0x88 Move Generation Algorithm which internally
|
|
* stores the board as an 8x16 array. This is purely for efficiency but has a
|
|
* couple of interesting benefits:
|
|
*
|
|
* 1. 0x88 offers a very inexpensive "off the board" check. Bitwise AND (&) any
|
|
* square with 0x88, if the result is non-zero then the square is off the
|
|
* board. For example, assuming a knight square A8 (0 in 0x88 notation),
|
|
* there are 8 possible directions in which the knight can move. These
|
|
* directions are relative to the 8x16 board and are stored in the
|
|
* PIECE_OFFSETS map. One possible move is A8 - 18 (up one square, and two
|
|
* squares to the left - which is off the board). 0 - 18 = -18 & 0x88 = 0x88
|
|
* (because of two-complement representation of -18). The non-zero result
|
|
* means the square is off the board and the move is illegal. Take the
|
|
* opposite move (from A8 to C7), 0 + 18 = 18 & 0x88 = 0. A result of zero
|
|
* means the square is on the board.
|
|
*
|
|
* 2. The relative distance (or difference) between two squares on a 8x16 board
|
|
* is unique and can be used to inexpensively determine if a piece on a
|
|
* square can attack any other arbitrary square. For example, let's see if a
|
|
* pawn on E7 can attack E2. The difference between E7 (20) - E2 (100) is
|
|
* -80. We add 119 to make the ATTACKS array index non-negative (because the
|
|
* worst case difference is A8 - H1 = -119). The ATTACKS array contains a
|
|
* bitmask of pieces that can attack from that distance and direction.
|
|
* ATTACKS[-80 + 119=39] gives us 24 or 0b11000 in binary. Look at the
|
|
* PIECE_MASKS map to determine the mask for a given piece type. In our pawn
|
|
* example, we would check to see if 24 & 0x1 is non-zero, which it is
|
|
* not. So, naturally, a pawn on E7 can't attack a piece on E2. However, a
|
|
* rook can since 24 & 0x8 is non-zero. The only thing left to check is that
|
|
* there are no blocking pieces between E7 and E2. That's where the RAYS
|
|
* array comes in. It provides an offset (in this case 16) to add to E7 (20)
|
|
* to check for blocking pieces. E7 (20) + 16 = E6 (36) + 16 = E5 (52) etc.
|
|
*/
|
|
// prettier-ignore
|
|
// eslint-disable-next-line
|
|
const Ox88 = {
|
|
a8: 0, b8: 1, c8: 2, d8: 3, e8: 4, f8: 5, g8: 6, h8: 7,
|
|
a7: 16, b7: 17, c7: 18, d7: 19, e7: 20, f7: 21, g7: 22, h7: 23,
|
|
a6: 32, b6: 33, c6: 34, d6: 35, e6: 36, f6: 37, g6: 38, h6: 39,
|
|
a5: 48, b5: 49, c5: 50, d5: 51, e5: 52, f5: 53, g5: 54, h5: 55,
|
|
a4: 64, b4: 65, c4: 66, d4: 67, e4: 68, f4: 69, g4: 70, h4: 71,
|
|
a3: 80, b3: 81, c3: 82, d3: 83, e3: 84, f3: 85, g3: 86, h3: 87,
|
|
a2: 96, b2: 97, c2: 98, d2: 99, e2: 100, f2: 101, g2: 102, h2: 103,
|
|
a1: 112, b1: 113, c1: 114, d1: 115, e1: 116, f1: 117, g1: 118, h1: 119
|
|
};
|
|
const PAWN_OFFSETS = {
|
|
b: [16, 32, 17, 15],
|
|
w: [-16, -32, -17, -15],
|
|
};
|
|
const PIECE_OFFSETS = {
|
|
n: [-18, -33, -31, -14, 18, 33, 31, 14],
|
|
b: [-17, -15, 17, 15],
|
|
r: [-16, 1, 16, -1],
|
|
q: [-17, -16, -15, 1, 17, 16, 15, -1],
|
|
k: [-17, -16, -15, 1, 17, 16, 15, -1],
|
|
};
|
|
// prettier-ignore
|
|
const ATTACKS = [
|
|
20, 0, 0, 0, 0, 0, 0, 24, 0, 0, 0, 0, 0, 0, 20, 0,
|
|
0, 20, 0, 0, 0, 0, 0, 24, 0, 0, 0, 0, 0, 20, 0, 0,
|
|
0, 0, 20, 0, 0, 0, 0, 24, 0, 0, 0, 0, 20, 0, 0, 0,
|
|
0, 0, 0, 20, 0, 0, 0, 24, 0, 0, 0, 20, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 20, 0, 0, 24, 0, 0, 20, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 20, 2, 24, 2, 20, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 2, 53, 56, 53, 2, 0, 0, 0, 0, 0, 0,
|
|
24, 24, 24, 24, 24, 24, 56, 0, 56, 24, 24, 24, 24, 24, 24, 0,
|
|
0, 0, 0, 0, 0, 2, 53, 56, 53, 2, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 20, 2, 24, 2, 20, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 20, 0, 0, 24, 0, 0, 20, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 20, 0, 0, 0, 24, 0, 0, 0, 20, 0, 0, 0, 0,
|
|
0, 0, 20, 0, 0, 0, 0, 24, 0, 0, 0, 0, 20, 0, 0, 0,
|
|
0, 20, 0, 0, 0, 0, 0, 24, 0, 0, 0, 0, 0, 20, 0, 0,
|
|
20, 0, 0, 0, 0, 0, 0, 24, 0, 0, 0, 0, 0, 0, 20
|
|
];
|
|
// prettier-ignore
|
|
const RAYS = [
|
|
17, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 15, 0,
|
|
0, 17, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 15, 0, 0,
|
|
0, 0, 17, 0, 0, 0, 0, 16, 0, 0, 0, 0, 15, 0, 0, 0,
|
|
0, 0, 0, 17, 0, 0, 0, 16, 0, 0, 0, 15, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 17, 0, 0, 16, 0, 0, 15, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 17, 0, 16, 0, 15, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 17, 16, 15, 0, 0, 0, 0, 0, 0, 0,
|
|
1, 1, 1, 1, 1, 1, 1, 0, -1, -1, -1, -1, -1, -1, -1, 0,
|
|
0, 0, 0, 0, 0, 0, -15, -16, -17, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, -15, 0, -16, 0, -17, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, -15, 0, 0, -16, 0, 0, -17, 0, 0, 0, 0, 0,
|
|
0, 0, 0, -15, 0, 0, 0, -16, 0, 0, 0, -17, 0, 0, 0, 0,
|
|
0, 0, -15, 0, 0, 0, 0, -16, 0, 0, 0, 0, -17, 0, 0, 0,
|
|
0, -15, 0, 0, 0, 0, 0, -16, 0, 0, 0, 0, 0, -17, 0, 0,
|
|
-15, 0, 0, 0, 0, 0, 0, -16, 0, 0, 0, 0, 0, 0, -17
|
|
];
|
|
const PIECE_MASKS = { p: 0x1, n: 0x2, b: 0x4, r: 0x8, q: 0x10, k: 0x20 };
|
|
const SYMBOLS = 'pnbrqkPNBRQK';
|
|
const PROMOTIONS = [KNIGHT, BISHOP, ROOK, QUEEN];
|
|
const RANK_1 = 7;
|
|
const RANK_2 = 6;
|
|
/*
|
|
* const RANK_3 = 5
|
|
* const RANK_4 = 4
|
|
* const RANK_5 = 3
|
|
* const RANK_6 = 2
|
|
*/
|
|
const RANK_7 = 1;
|
|
const RANK_8 = 0;
|
|
const SIDES = {
|
|
[KING]: BITS.KSIDE_CASTLE,
|
|
[QUEEN]: BITS.QSIDE_CASTLE,
|
|
};
|
|
const ROOKS = {
|
|
w: [
|
|
{ square: Ox88.a1, flag: BITS.QSIDE_CASTLE },
|
|
{ square: Ox88.h1, flag: BITS.KSIDE_CASTLE },
|
|
],
|
|
b: [
|
|
{ square: Ox88.a8, flag: BITS.QSIDE_CASTLE },
|
|
{ square: Ox88.h8, flag: BITS.KSIDE_CASTLE },
|
|
],
|
|
};
|
|
const SECOND_RANK = { b: RANK_7, w: RANK_2 };
|
|
const SAN_NULLMOVE = '--';
|
|
// Extracts the zero-based rank of an 0x88 square.
|
|
function rank(square) {
|
|
return square >> 4;
|
|
}
|
|
// Extracts the zero-based file of an 0x88 square.
|
|
function file(square) {
|
|
return square & 0xf;
|
|
}
|
|
function isDigit(c) {
|
|
return '0123456789'.indexOf(c) !== -1;
|
|
}
|
|
// Converts a 0x88 square to algebraic notation.
|
|
function algebraic(square) {
|
|
const f = file(square);
|
|
const r = rank(square);
|
|
return ('abcdefgh'.substring(f, f + 1) +
|
|
'87654321'.substring(r, r + 1));
|
|
}
|
|
function swapColor(color) {
|
|
return color === WHITE ? BLACK : WHITE;
|
|
}
|
|
function validateFen(fen) {
|
|
// 1st criterion: 6 space-seperated fields?
|
|
const tokens = fen.split(/\s+/);
|
|
if (tokens.length !== 6) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: must contain six space-delimited fields',
|
|
};
|
|
}
|
|
// 2nd criterion: move number field is a integer value > 0?
|
|
const moveNumber = parseInt(tokens[5], 10);
|
|
if (isNaN(moveNumber) || moveNumber <= 0) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: move number must be a positive integer',
|
|
};
|
|
}
|
|
// 3rd criterion: half move counter is an integer >= 0?
|
|
const halfMoves = parseInt(tokens[4], 10);
|
|
if (isNaN(halfMoves) || halfMoves < 0) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: half move counter number must be a non-negative integer',
|
|
};
|
|
}
|
|
// 4th criterion: 4th field is a valid e.p.-string?
|
|
if (!/^(-|[abcdefgh][36])$/.test(tokens[3])) {
|
|
return { ok: false, error: 'Invalid FEN: en-passant square is invalid' };
|
|
}
|
|
// 5th criterion: 3th field is a valid castle-string?
|
|
if (/[^kKqQ-]/.test(tokens[2])) {
|
|
return { ok: false, error: 'Invalid FEN: castling availability is invalid' };
|
|
}
|
|
// 6th criterion: 2nd field is "w" (white) or "b" (black)?
|
|
if (!/^(w|b)$/.test(tokens[1])) {
|
|
return { ok: false, error: 'Invalid FEN: side-to-move is invalid' };
|
|
}
|
|
// 7th criterion: 1st field contains 8 rows?
|
|
const rows = tokens[0].split('/');
|
|
if (rows.length !== 8) {
|
|
return {
|
|
ok: false,
|
|
error: "Invalid FEN: piece data does not contain 8 '/'-delimited rows",
|
|
};
|
|
}
|
|
// 8th criterion: every row is valid?
|
|
for (let i = 0; i < rows.length; i++) {
|
|
// check for right sum of fields AND not two numbers in succession
|
|
let sumFields = 0;
|
|
let previousWasNumber = false;
|
|
for (let k = 0; k < rows[i].length; k++) {
|
|
if (isDigit(rows[i][k])) {
|
|
if (previousWasNumber) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: piece data is invalid (consecutive number)',
|
|
};
|
|
}
|
|
sumFields += parseInt(rows[i][k], 10);
|
|
previousWasNumber = true;
|
|
}
|
|
else {
|
|
if (!/^[prnbqkPRNBQK]$/.test(rows[i][k])) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: piece data is invalid (invalid piece)',
|
|
};
|
|
}
|
|
sumFields += 1;
|
|
previousWasNumber = false;
|
|
}
|
|
}
|
|
if (sumFields !== 8) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: piece data is invalid (too many squares in rank)',
|
|
};
|
|
}
|
|
}
|
|
// 9th criterion: is en-passant square legal?
|
|
if ((tokens[3][1] == '3' && tokens[1] == 'w') ||
|
|
(tokens[3][1] == '6' && tokens[1] == 'b')) {
|
|
return { ok: false, error: 'Invalid FEN: illegal en-passant square' };
|
|
}
|
|
// 10th criterion: does chess position contain exact two kings?
|
|
const kings = [
|
|
{ color: 'white', regex: /K/g },
|
|
{ color: 'black', regex: /k/g },
|
|
];
|
|
for (const { color, regex } of kings) {
|
|
if (!regex.test(tokens[0])) {
|
|
return { ok: false, error: `Invalid FEN: missing ${color} king` };
|
|
}
|
|
if ((tokens[0].match(regex) || []).length > 1) {
|
|
return { ok: false, error: `Invalid FEN: too many ${color} kings` };
|
|
}
|
|
}
|
|
// 11th criterion: are any pawns on the first or eighth rows?
|
|
if (Array.from(rows[0] + rows[7]).some((char) => char.toUpperCase() === 'P')) {
|
|
return {
|
|
ok: false,
|
|
error: 'Invalid FEN: some pawns are on the edge rows',
|
|
};
|
|
}
|
|
return { ok: true };
|
|
}
|
|
// this function is used to uniquely identify ambiguous moves
|
|
function getDisambiguator(move, moves) {
|
|
const from = move.from;
|
|
const to = move.to;
|
|
const piece = move.piece;
|
|
let ambiguities = 0;
|
|
let sameRank = 0;
|
|
let sameFile = 0;
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
const ambigFrom = moves[i].from;
|
|
const ambigTo = moves[i].to;
|
|
const ambigPiece = moves[i].piece;
|
|
/*
|
|
* if a move of the same piece type ends on the same to square, we'll need
|
|
* to add a disambiguator to the algebraic notation
|
|
*/
|
|
if (piece === ambigPiece && from !== ambigFrom && to === ambigTo) {
|
|
ambiguities++;
|
|
if (rank(from) === rank(ambigFrom)) {
|
|
sameRank++;
|
|
}
|
|
if (file(from) === file(ambigFrom)) {
|
|
sameFile++;
|
|
}
|
|
}
|
|
}
|
|
if (ambiguities > 0) {
|
|
if (sameRank > 0 && sameFile > 0) {
|
|
/*
|
|
* if there exists a similar moving piece on the same rank and file as
|
|
* the move in question, use the square as the disambiguator
|
|
*/
|
|
return algebraic(from);
|
|
}
|
|
else if (sameFile > 0) {
|
|
/*
|
|
* if the moving piece rests on the same file, use the rank symbol as the
|
|
* disambiguator
|
|
*/
|
|
return algebraic(from).charAt(1);
|
|
}
|
|
else {
|
|
// else use the file symbol
|
|
return algebraic(from).charAt(0);
|
|
}
|
|
}
|
|
return '';
|
|
}
|
|
function addMove(moves, color, from, to, piece, captured = undefined, flags = BITS.NORMAL) {
|
|
const r = rank(to);
|
|
if (piece === PAWN && (r === RANK_1 || r === RANK_8)) {
|
|
for (let i = 0; i < PROMOTIONS.length; i++) {
|
|
const promotion = PROMOTIONS[i];
|
|
moves.push({
|
|
color,
|
|
from,
|
|
to,
|
|
piece,
|
|
captured,
|
|
promotion,
|
|
flags: flags | BITS.PROMOTION,
|
|
});
|
|
}
|
|
}
|
|
else {
|
|
moves.push({
|
|
color,
|
|
from,
|
|
to,
|
|
piece,
|
|
captured,
|
|
flags,
|
|
});
|
|
}
|
|
}
|
|
function inferPieceType(san) {
|
|
let pieceType = san.charAt(0);
|
|
if (pieceType >= 'a' && pieceType <= 'h') {
|
|
const matches = san.match(/[a-h]\d.*[a-h]\d/);
|
|
if (matches) {
|
|
return undefined;
|
|
}
|
|
return PAWN;
|
|
}
|
|
pieceType = pieceType.toLowerCase();
|
|
if (pieceType === 'o') {
|
|
return KING;
|
|
}
|
|
return pieceType;
|
|
}
|
|
// parses all of the decorators out of a SAN string
|
|
function strippedSan(move) {
|
|
return move.replace(/=/, '').replace(/[+#]?[?!]*$/, '');
|
|
}
|
|
class Chess {
|
|
_board = new Array(128);
|
|
_turn = WHITE;
|
|
_header = {};
|
|
_kings = { w: EMPTY, b: EMPTY };
|
|
_epSquare = -1;
|
|
_halfMoves = 0;
|
|
_moveNumber = 0;
|
|
_history = [];
|
|
_comments = {};
|
|
_castling = { w: 0, b: 0 };
|
|
_hash = 0n;
|
|
// tracks number of times a position has been seen for repetition checking
|
|
_positionCount = new Map();
|
|
constructor(fen = DEFAULT_POSITION, { skipValidation = false } = {}) {
|
|
this.load(fen, { skipValidation });
|
|
}
|
|
clear({ preserveHeaders = false } = {}) {
|
|
this._board = new Array(128);
|
|
this._kings = { w: EMPTY, b: EMPTY };
|
|
this._turn = WHITE;
|
|
this._castling = { w: 0, b: 0 };
|
|
this._epSquare = EMPTY;
|
|
this._halfMoves = 0;
|
|
this._moveNumber = 1;
|
|
this._history = [];
|
|
this._comments = {};
|
|
this._header = preserveHeaders ? this._header : { ...HEADER_TEMPLATE };
|
|
this._hash = this._computeHash();
|
|
this._positionCount = new Map();
|
|
/*
|
|
* Delete the SetUp and FEN headers (if preserved), the board is empty and
|
|
* these headers don't make sense in this state. They'll get added later
|
|
* via .load() or .put()
|
|
*/
|
|
this._header['SetUp'] = null;
|
|
this._header['FEN'] = null;
|
|
}
|
|
load(fen, { skipValidation = false, preserveHeaders = false } = {}) {
|
|
let tokens = fen.split(/\s+/);
|
|
// append commonly omitted fen tokens
|
|
if (tokens.length >= 2 && tokens.length < 6) {
|
|
const adjustments = ['-', '-', '0', '1'];
|
|
fen = tokens.concat(adjustments.slice(-(6 - tokens.length))).join(' ');
|
|
}
|
|
tokens = fen.split(/\s+/);
|
|
if (!skipValidation) {
|
|
const { ok, error } = validateFen(fen);
|
|
if (!ok) {
|
|
throw new Error(error);
|
|
}
|
|
}
|
|
const position = tokens[0];
|
|
let square = 0;
|
|
this.clear({ preserveHeaders });
|
|
for (let i = 0; i < position.length; i++) {
|
|
const piece = position.charAt(i);
|
|
if (piece === '/') {
|
|
square += 8;
|
|
}
|
|
else if (isDigit(piece)) {
|
|
square += parseInt(piece, 10);
|
|
}
|
|
else {
|
|
const color = piece < 'a' ? WHITE : BLACK;
|
|
this._put({ type: piece.toLowerCase(), color }, algebraic(square));
|
|
square++;
|
|
}
|
|
}
|
|
this._turn = tokens[1];
|
|
if (tokens[2].indexOf('K') > -1) {
|
|
this._castling.w |= BITS.KSIDE_CASTLE;
|
|
}
|
|
if (tokens[2].indexOf('Q') > -1) {
|
|
this._castling.w |= BITS.QSIDE_CASTLE;
|
|
}
|
|
if (tokens[2].indexOf('k') > -1) {
|
|
this._castling.b |= BITS.KSIDE_CASTLE;
|
|
}
|
|
if (tokens[2].indexOf('q') > -1) {
|
|
this._castling.b |= BITS.QSIDE_CASTLE;
|
|
}
|
|
this._epSquare = tokens[3] === '-' ? EMPTY : Ox88[tokens[3]];
|
|
this._halfMoves = parseInt(tokens[4], 10);
|
|
this._moveNumber = parseInt(tokens[5], 10);
|
|
this._hash = this._computeHash();
|
|
this._updateSetup(fen);
|
|
this._incPositionCount();
|
|
}
|
|
fen({ forceEnpassantSquare = false, } = {}) {
|
|
let empty = 0;
|
|
let fen = '';
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
if (this._board[i]) {
|
|
if (empty > 0) {
|
|
fen += empty;
|
|
empty = 0;
|
|
}
|
|
const { color, type: piece } = this._board[i];
|
|
fen += color === WHITE ? piece.toUpperCase() : piece.toLowerCase();
|
|
}
|
|
else {
|
|
empty++;
|
|
}
|
|
if ((i + 1) & 0x88) {
|
|
if (empty > 0) {
|
|
fen += empty;
|
|
}
|
|
if (i !== Ox88.h1) {
|
|
fen += '/';
|
|
}
|
|
empty = 0;
|
|
i += 8;
|
|
}
|
|
}
|
|
let castling = '';
|
|
if (this._castling[WHITE] & BITS.KSIDE_CASTLE) {
|
|
castling += 'K';
|
|
}
|
|
if (this._castling[WHITE] & BITS.QSIDE_CASTLE) {
|
|
castling += 'Q';
|
|
}
|
|
if (this._castling[BLACK] & BITS.KSIDE_CASTLE) {
|
|
castling += 'k';
|
|
}
|
|
if (this._castling[BLACK] & BITS.QSIDE_CASTLE) {
|
|
castling += 'q';
|
|
}
|
|
// do we have an empty castling flag?
|
|
castling = castling || '-';
|
|
let epSquare = '-';
|
|
/*
|
|
* only print the ep square if en passant is a valid move (pawn is present
|
|
* and ep capture is not pinned)
|
|
*/
|
|
if (this._epSquare !== EMPTY) {
|
|
if (forceEnpassantSquare) {
|
|
epSquare = algebraic(this._epSquare);
|
|
}
|
|
else {
|
|
const bigPawnSquare = this._epSquare + (this._turn === WHITE ? 16 : -16);
|
|
const squares = [bigPawnSquare + 1, bigPawnSquare - 1];
|
|
for (const square of squares) {
|
|
// is the square off the board?
|
|
if (square & 0x88) {
|
|
continue;
|
|
}
|
|
const color = this._turn;
|
|
// is there a pawn that can capture the epSquare?
|
|
if (this._board[square]?.color === color &&
|
|
this._board[square]?.type === PAWN) {
|
|
// if the pawn makes an ep capture, does it leave its king in check?
|
|
this._makeMove({
|
|
color,
|
|
from: square,
|
|
to: this._epSquare,
|
|
piece: PAWN,
|
|
captured: PAWN,
|
|
flags: BITS.EP_CAPTURE,
|
|
});
|
|
const isLegal = !this._isKingAttacked(color);
|
|
this._undoMove();
|
|
// if ep is legal, break and set the ep square in the FEN output
|
|
if (isLegal) {
|
|
epSquare = algebraic(this._epSquare);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return [
|
|
fen,
|
|
this._turn,
|
|
castling,
|
|
epSquare,
|
|
this._halfMoves,
|
|
this._moveNumber,
|
|
].join(' ');
|
|
}
|
|
_pieceKey(i) {
|
|
if (!this._board[i]) {
|
|
return 0n;
|
|
}
|
|
const { color, type } = this._board[i];
|
|
const colorIndex = {
|
|
w: 0,
|
|
b: 1,
|
|
}[color];
|
|
const typeIndex = {
|
|
p: 0,
|
|
n: 1,
|
|
b: 2,
|
|
r: 3,
|
|
q: 4,
|
|
k: 5,
|
|
}[type];
|
|
return PIECE_KEYS[colorIndex][typeIndex][i];
|
|
}
|
|
_epKey() {
|
|
return this._epSquare === EMPTY ? 0n : EP_KEYS[this._epSquare & 7];
|
|
}
|
|
_castlingKey() {
|
|
const index = (this._castling.w >> 5) | (this._castling.b >> 3);
|
|
return CASTLING_KEYS[index];
|
|
}
|
|
_computeHash() {
|
|
let hash = 0n;
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
// did we run off the end of the board
|
|
if (i & 0x88) {
|
|
i += 7;
|
|
continue;
|
|
}
|
|
if (this._board[i]) {
|
|
hash ^= this._pieceKey(i);
|
|
}
|
|
}
|
|
hash ^= this._epKey();
|
|
hash ^= this._castlingKey();
|
|
if (this._turn === 'b') {
|
|
hash ^= SIDE_KEY;
|
|
}
|
|
return hash;
|
|
}
|
|
/*
|
|
* Called when the initial board setup is changed with put() or remove().
|
|
* modifies the SetUp and FEN properties of the header object. If the FEN
|
|
* is equal to the default position, the SetUp and FEN are deleted the setup
|
|
* is only updated if history.length is zero, ie moves haven't been made.
|
|
*/
|
|
_updateSetup(fen) {
|
|
if (this._history.length > 0)
|
|
return;
|
|
if (fen !== DEFAULT_POSITION) {
|
|
this._header['SetUp'] = '1';
|
|
this._header['FEN'] = fen;
|
|
}
|
|
else {
|
|
this._header['SetUp'] = null;
|
|
this._header['FEN'] = null;
|
|
}
|
|
}
|
|
reset() {
|
|
this.load(DEFAULT_POSITION);
|
|
}
|
|
get(square) {
|
|
return this._board[Ox88[square]];
|
|
}
|
|
findPiece(piece) {
|
|
const squares = [];
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
// did we run off the end of the board
|
|
if (i & 0x88) {
|
|
i += 7;
|
|
continue;
|
|
}
|
|
// if empty square or wrong color
|
|
if (!this._board[i] || this._board[i]?.color !== piece.color) {
|
|
continue;
|
|
}
|
|
// check if square contains the requested piece
|
|
if (this._board[i].color === piece.color &&
|
|
this._board[i].type === piece.type) {
|
|
squares.push(algebraic(i));
|
|
}
|
|
}
|
|
return squares;
|
|
}
|
|
put({ type, color }, square) {
|
|
if (this._put({ type, color }, square)) {
|
|
this._updateCastlingRights();
|
|
this._updateEnPassantSquare();
|
|
this._updateSetup(this.fen());
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
_set(sq, piece) {
|
|
this._hash ^= this._pieceKey(sq);
|
|
this._board[sq] = piece;
|
|
this._hash ^= this._pieceKey(sq);
|
|
}
|
|
_put({ type, color }, square) {
|
|
// check for piece
|
|
if (SYMBOLS.indexOf(type.toLowerCase()) === -1) {
|
|
return false;
|
|
}
|
|
// check for valid square
|
|
if (!(square in Ox88)) {
|
|
return false;
|
|
}
|
|
const sq = Ox88[square];
|
|
// don't let the user place more than one king
|
|
if (type == KING &&
|
|
!(this._kings[color] == EMPTY || this._kings[color] == sq)) {
|
|
return false;
|
|
}
|
|
const currentPieceOnSquare = this._board[sq];
|
|
// if one of the kings will be replaced by the piece from args, set the `_kings` respective entry to `EMPTY`
|
|
if (currentPieceOnSquare && currentPieceOnSquare.type === KING) {
|
|
this._kings[currentPieceOnSquare.color] = EMPTY;
|
|
}
|
|
this._set(sq, { type: type, color: color });
|
|
if (type === KING) {
|
|
this._kings[color] = sq;
|
|
}
|
|
return true;
|
|
}
|
|
_clear(sq) {
|
|
this._hash ^= this._pieceKey(sq);
|
|
delete this._board[sq];
|
|
}
|
|
remove(square) {
|
|
const piece = this.get(square);
|
|
this._clear(Ox88[square]);
|
|
if (piece && piece.type === KING) {
|
|
this._kings[piece.color] = EMPTY;
|
|
}
|
|
this._updateCastlingRights();
|
|
this._updateEnPassantSquare();
|
|
this._updateSetup(this.fen());
|
|
return piece;
|
|
}
|
|
_updateCastlingRights() {
|
|
this._hash ^= this._castlingKey();
|
|
const whiteKingInPlace = this._board[Ox88.e1]?.type === KING &&
|
|
this._board[Ox88.e1]?.color === WHITE;
|
|
const blackKingInPlace = this._board[Ox88.e8]?.type === KING &&
|
|
this._board[Ox88.e8]?.color === BLACK;
|
|
if (!whiteKingInPlace ||
|
|
this._board[Ox88.a1]?.type !== ROOK ||
|
|
this._board[Ox88.a1]?.color !== WHITE) {
|
|
this._castling.w &= -65;
|
|
}
|
|
if (!whiteKingInPlace ||
|
|
this._board[Ox88.h1]?.type !== ROOK ||
|
|
this._board[Ox88.h1]?.color !== WHITE) {
|
|
this._castling.w &= -33;
|
|
}
|
|
if (!blackKingInPlace ||
|
|
this._board[Ox88.a8]?.type !== ROOK ||
|
|
this._board[Ox88.a8]?.color !== BLACK) {
|
|
this._castling.b &= -65;
|
|
}
|
|
if (!blackKingInPlace ||
|
|
this._board[Ox88.h8]?.type !== ROOK ||
|
|
this._board[Ox88.h8]?.color !== BLACK) {
|
|
this._castling.b &= -33;
|
|
}
|
|
this._hash ^= this._castlingKey();
|
|
}
|
|
_updateEnPassantSquare() {
|
|
if (this._epSquare === EMPTY) {
|
|
return;
|
|
}
|
|
const startSquare = this._epSquare + (this._turn === WHITE ? -16 : 16);
|
|
const currentSquare = this._epSquare + (this._turn === WHITE ? 16 : -16);
|
|
const attackers = [currentSquare + 1, currentSquare - 1];
|
|
if (this._board[startSquare] !== null ||
|
|
this._board[this._epSquare] !== null ||
|
|
this._board[currentSquare]?.color !== swapColor(this._turn) ||
|
|
this._board[currentSquare]?.type !== PAWN) {
|
|
this._hash ^= this._epKey();
|
|
this._epSquare = EMPTY;
|
|
return;
|
|
}
|
|
const canCapture = (square) => !(square & 0x88) &&
|
|
this._board[square]?.color === this._turn &&
|
|
this._board[square]?.type === PAWN;
|
|
if (!attackers.some(canCapture)) {
|
|
this._hash ^= this._epKey();
|
|
this._epSquare = EMPTY;
|
|
}
|
|
}
|
|
_attacked(color, square, verbose) {
|
|
const attackers = [];
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
// did we run off the end of the board
|
|
if (i & 0x88) {
|
|
i += 7;
|
|
continue;
|
|
}
|
|
// if empty square or wrong color
|
|
if (this._board[i] === undefined || this._board[i].color !== color) {
|
|
continue;
|
|
}
|
|
const piece = this._board[i];
|
|
const difference = i - square;
|
|
// skip - to/from square are the same
|
|
if (difference === 0) {
|
|
continue;
|
|
}
|
|
const index = difference + 119;
|
|
if (ATTACKS[index] & PIECE_MASKS[piece.type]) {
|
|
if (piece.type === PAWN) {
|
|
if ((difference > 0 && piece.color === WHITE) ||
|
|
(difference <= 0 && piece.color === BLACK)) {
|
|
if (!verbose) {
|
|
return true;
|
|
}
|
|
else {
|
|
attackers.push(algebraic(i));
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
// if the piece is a knight or a king
|
|
if (piece.type === 'n' || piece.type === 'k') {
|
|
if (!verbose) {
|
|
return true;
|
|
}
|
|
else {
|
|
attackers.push(algebraic(i));
|
|
continue;
|
|
}
|
|
}
|
|
const offset = RAYS[index];
|
|
let j = i + offset;
|
|
let blocked = false;
|
|
while (j !== square) {
|
|
if (this._board[j] != null) {
|
|
blocked = true;
|
|
break;
|
|
}
|
|
j += offset;
|
|
}
|
|
if (!blocked) {
|
|
if (!verbose) {
|
|
return true;
|
|
}
|
|
else {
|
|
attackers.push(algebraic(i));
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (verbose) {
|
|
return attackers;
|
|
}
|
|
else {
|
|
return false;
|
|
}
|
|
}
|
|
attackers(square, attackedBy) {
|
|
if (!attackedBy) {
|
|
return this._attacked(this._turn, Ox88[square], true);
|
|
}
|
|
else {
|
|
return this._attacked(attackedBy, Ox88[square], true);
|
|
}
|
|
}
|
|
_isKingAttacked(color) {
|
|
const square = this._kings[color];
|
|
return square === -1 ? false : this._attacked(swapColor(color), square);
|
|
}
|
|
hash() {
|
|
return this._hash.toString(16);
|
|
}
|
|
isAttacked(square, attackedBy) {
|
|
return this._attacked(attackedBy, Ox88[square]);
|
|
}
|
|
isCheck() {
|
|
return this._isKingAttacked(this._turn);
|
|
}
|
|
inCheck() {
|
|
return this.isCheck();
|
|
}
|
|
isCheckmate() {
|
|
return this.isCheck() && this._moves().length === 0;
|
|
}
|
|
isStalemate() {
|
|
return !this.isCheck() && this._moves().length === 0;
|
|
}
|
|
isInsufficientMaterial() {
|
|
/*
|
|
* k.b. vs k.b. (of opposite colors) with mate in 1:
|
|
* 8/8/8/8/1b6/8/B1k5/K7 b - - 0 1
|
|
*
|
|
* k.b. vs k.n. with mate in 1:
|
|
* 8/8/8/8/1n6/8/B7/K1k5 b - - 2 1
|
|
*/
|
|
const pieces = {
|
|
b: 0,
|
|
n: 0,
|
|
r: 0,
|
|
q: 0,
|
|
k: 0,
|
|
p: 0,
|
|
};
|
|
const bishops = [];
|
|
let numPieces = 0;
|
|
let squareColor = 0;
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
squareColor = (squareColor + 1) % 2;
|
|
if (i & 0x88) {
|
|
i += 7;
|
|
continue;
|
|
}
|
|
const piece = this._board[i];
|
|
if (piece) {
|
|
pieces[piece.type] = piece.type in pieces ? pieces[piece.type] + 1 : 1;
|
|
if (piece.type === BISHOP) {
|
|
bishops.push(squareColor);
|
|
}
|
|
numPieces++;
|
|
}
|
|
}
|
|
// k vs. k
|
|
if (numPieces === 2) {
|
|
return true;
|
|
}
|
|
else if (
|
|
// k vs. kn .... or .... k vs. kb
|
|
numPieces === 3 &&
|
|
(pieces[BISHOP] === 1 || pieces[KNIGHT] === 1)) {
|
|
return true;
|
|
}
|
|
else if (numPieces === pieces[BISHOP] + 2) {
|
|
// kb vs. kb where any number of bishops are all on the same color
|
|
let sum = 0;
|
|
const len = bishops.length;
|
|
for (let i = 0; i < len; i++) {
|
|
sum += bishops[i];
|
|
}
|
|
if (sum === 0 || sum === len) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
isThreefoldRepetition() {
|
|
return this._getPositionCount(this._hash) >= 3;
|
|
}
|
|
isDrawByFiftyMoves() {
|
|
return this._halfMoves >= 100; // 50 moves per side = 100 half moves
|
|
}
|
|
isDraw() {
|
|
return (this.isDrawByFiftyMoves() ||
|
|
this.isStalemate() ||
|
|
this.isInsufficientMaterial() ||
|
|
this.isThreefoldRepetition());
|
|
}
|
|
isGameOver() {
|
|
return this.isCheckmate() || this.isDraw();
|
|
}
|
|
moves({ verbose = false, square = undefined, piece = undefined, } = {}) {
|
|
const moves = this._moves({ square, piece });
|
|
if (verbose) {
|
|
return moves.map((move) => new Move(this, move));
|
|
}
|
|
else {
|
|
return moves.map((move) => this._moveToSan(move, moves));
|
|
}
|
|
}
|
|
_moves({ legal = true, piece = undefined, square = undefined, } = {}) {
|
|
const forSquare = square ? square.toLowerCase() : undefined;
|
|
const forPiece = piece?.toLowerCase();
|
|
const moves = [];
|
|
const us = this._turn;
|
|
const them = swapColor(us);
|
|
let firstSquare = Ox88.a8;
|
|
let lastSquare = Ox88.h1;
|
|
let singleSquare = false;
|
|
// are we generating moves for a single square?
|
|
if (forSquare) {
|
|
// illegal square, return empty moves
|
|
if (!(forSquare in Ox88)) {
|
|
return [];
|
|
}
|
|
else {
|
|
firstSquare = lastSquare = Ox88[forSquare];
|
|
singleSquare = true;
|
|
}
|
|
}
|
|
for (let from = firstSquare; from <= lastSquare; from++) {
|
|
// did we run off the end of the board
|
|
if (from & 0x88) {
|
|
from += 7;
|
|
continue;
|
|
}
|
|
// empty square or opponent, skip
|
|
if (!this._board[from] || this._board[from].color === them) {
|
|
continue;
|
|
}
|
|
const { type } = this._board[from];
|
|
let to;
|
|
if (type === PAWN) {
|
|
if (forPiece && forPiece !== type)
|
|
continue;
|
|
// single square, non-capturing
|
|
to = from + PAWN_OFFSETS[us][0];
|
|
if (!this._board[to]) {
|
|
addMove(moves, us, from, to, PAWN);
|
|
// double square
|
|
to = from + PAWN_OFFSETS[us][1];
|
|
if (SECOND_RANK[us] === rank(from) && !this._board[to]) {
|
|
addMove(moves, us, from, to, PAWN, undefined, BITS.BIG_PAWN);
|
|
}
|
|
}
|
|
// pawn captures
|
|
for (let j = 2; j < 4; j++) {
|
|
to = from + PAWN_OFFSETS[us][j];
|
|
if (to & 0x88)
|
|
continue;
|
|
if (this._board[to]?.color === them) {
|
|
addMove(moves, us, from, to, PAWN, this._board[to].type, BITS.CAPTURE);
|
|
}
|
|
else if (to === this._epSquare) {
|
|
addMove(moves, us, from, to, PAWN, PAWN, BITS.EP_CAPTURE);
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
if (forPiece && forPiece !== type)
|
|
continue;
|
|
for (let j = 0, len = PIECE_OFFSETS[type].length; j < len; j++) {
|
|
const offset = PIECE_OFFSETS[type][j];
|
|
to = from;
|
|
while (true) {
|
|
to += offset;
|
|
if (to & 0x88)
|
|
break;
|
|
if (!this._board[to]) {
|
|
addMove(moves, us, from, to, type);
|
|
}
|
|
else {
|
|
// own color, stop loop
|
|
if (this._board[to].color === us)
|
|
break;
|
|
addMove(moves, us, from, to, type, this._board[to].type, BITS.CAPTURE);
|
|
break;
|
|
}
|
|
/* break, if knight or king */
|
|
if (type === KNIGHT || type === KING)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
/*
|
|
* check for castling if we're:
|
|
* a) generating all moves, or
|
|
* b) doing single square move generation on the king's square
|
|
*/
|
|
if (forPiece === undefined || forPiece === KING) {
|
|
if (!singleSquare || lastSquare === this._kings[us]) {
|
|
// king-side castling
|
|
if (this._castling[us] & BITS.KSIDE_CASTLE) {
|
|
const castlingFrom = this._kings[us];
|
|
const castlingTo = castlingFrom + 2;
|
|
if (!this._board[castlingFrom + 1] &&
|
|
!this._board[castlingTo] &&
|
|
!this._attacked(them, this._kings[us]) &&
|
|
!this._attacked(them, castlingFrom + 1) &&
|
|
!this._attacked(them, castlingTo)) {
|
|
addMove(moves, us, this._kings[us], castlingTo, KING, undefined, BITS.KSIDE_CASTLE);
|
|
}
|
|
}
|
|
// queen-side castling
|
|
if (this._castling[us] & BITS.QSIDE_CASTLE) {
|
|
const castlingFrom = this._kings[us];
|
|
const castlingTo = castlingFrom - 2;
|
|
if (!this._board[castlingFrom - 1] &&
|
|
!this._board[castlingFrom - 2] &&
|
|
!this._board[castlingFrom - 3] &&
|
|
!this._attacked(them, this._kings[us]) &&
|
|
!this._attacked(them, castlingFrom - 1) &&
|
|
!this._attacked(them, castlingTo)) {
|
|
addMove(moves, us, this._kings[us], castlingTo, KING, undefined, BITS.QSIDE_CASTLE);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
/*
|
|
* return all pseudo-legal moves (this includes moves that allow the king
|
|
* to be captured)
|
|
*/
|
|
if (!legal || this._kings[us] === -1) {
|
|
return moves;
|
|
}
|
|
// filter out illegal moves
|
|
const legalMoves = [];
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
this._makeMove(moves[i]);
|
|
if (!this._isKingAttacked(us)) {
|
|
legalMoves.push(moves[i]);
|
|
}
|
|
this._undoMove();
|
|
}
|
|
return legalMoves;
|
|
}
|
|
move(move, { strict = false } = {}) {
|
|
/*
|
|
* The move function can be called with in the following parameters:
|
|
*
|
|
* .move('Nxb7') <- argument is a case-sensitive SAN string
|
|
*
|
|
* .move({ from: 'h7', <- argument is a move object
|
|
* to :'h8',
|
|
* promotion: 'q' })
|
|
*
|
|
*
|
|
* An optional strict argument may be supplied to tell chess.js to
|
|
* strictly follow the SAN specification.
|
|
*/
|
|
let moveObj = null;
|
|
if (typeof move === 'string') {
|
|
moveObj = this._moveFromSan(move, strict);
|
|
}
|
|
else if (move === null) {
|
|
moveObj = this._moveFromSan(SAN_NULLMOVE, strict);
|
|
}
|
|
else if (typeof move === 'object') {
|
|
const moves = this._moves();
|
|
// convert the pretty move object to an ugly move object
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
if (move.from === algebraic(moves[i].from) &&
|
|
move.to === algebraic(moves[i].to) &&
|
|
(!('promotion' in moves[i]) || move.promotion === moves[i].promotion)) {
|
|
moveObj = moves[i];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// failed to find move
|
|
if (!moveObj) {
|
|
if (typeof move === 'string') {
|
|
throw new Error(`Invalid move: ${move}`);
|
|
}
|
|
else {
|
|
throw new Error(`Invalid move: ${JSON.stringify(move)}`);
|
|
}
|
|
}
|
|
//disallow null moves when in check
|
|
if (this.isCheck() && moveObj.flags & BITS.NULL_MOVE) {
|
|
throw new Error('Null move not allowed when in check');
|
|
}
|
|
/*
|
|
* need to make a copy of move because we can't generate SAN after the move
|
|
* is made
|
|
*/
|
|
const prettyMove = new Move(this, moveObj);
|
|
this._makeMove(moveObj);
|
|
this._incPositionCount();
|
|
return prettyMove;
|
|
}
|
|
_push(move) {
|
|
this._history.push({
|
|
move,
|
|
kings: { b: this._kings.b, w: this._kings.w },
|
|
turn: this._turn,
|
|
castling: { b: this._castling.b, w: this._castling.w },
|
|
epSquare: this._epSquare,
|
|
halfMoves: this._halfMoves,
|
|
moveNumber: this._moveNumber,
|
|
});
|
|
}
|
|
_movePiece(from, to) {
|
|
this._hash ^= this._pieceKey(from);
|
|
this._board[to] = this._board[from];
|
|
delete this._board[from];
|
|
this._hash ^= this._pieceKey(to);
|
|
}
|
|
_makeMove(move) {
|
|
const us = this._turn;
|
|
const them = swapColor(us);
|
|
this._push(move);
|
|
if (move.flags & BITS.NULL_MOVE) {
|
|
if (us === BLACK) {
|
|
this._moveNumber++;
|
|
}
|
|
this._halfMoves++;
|
|
this._turn = them;
|
|
this._epSquare = EMPTY;
|
|
return;
|
|
}
|
|
this._hash ^= this._epKey();
|
|
this._hash ^= this._castlingKey();
|
|
if (move.captured) {
|
|
this._hash ^= this._pieceKey(move.to);
|
|
}
|
|
this._movePiece(move.from, move.to);
|
|
// if ep capture, remove the captured pawn
|
|
if (move.flags & BITS.EP_CAPTURE) {
|
|
if (this._turn === BLACK) {
|
|
this._clear(move.to - 16);
|
|
}
|
|
else {
|
|
this._clear(move.to + 16);
|
|
}
|
|
}
|
|
// if pawn promotion, replace with new piece
|
|
if (move.promotion) {
|
|
this._clear(move.to);
|
|
this._set(move.to, { type: move.promotion, color: us });
|
|
}
|
|
// if we moved the king
|
|
if (this._board[move.to].type === KING) {
|
|
this._kings[us] = move.to;
|
|
// if we castled, move the rook next to the king
|
|
if (move.flags & BITS.KSIDE_CASTLE) {
|
|
const castlingTo = move.to - 1;
|
|
const castlingFrom = move.to + 1;
|
|
this._movePiece(castlingFrom, castlingTo);
|
|
}
|
|
else if (move.flags & BITS.QSIDE_CASTLE) {
|
|
const castlingTo = move.to + 1;
|
|
const castlingFrom = move.to - 2;
|
|
this._movePiece(castlingFrom, castlingTo);
|
|
}
|
|
// turn off castling
|
|
this._castling[us] = 0;
|
|
}
|
|
// turn off castling if we move a rook
|
|
if (this._castling[us]) {
|
|
for (let i = 0, len = ROOKS[us].length; i < len; i++) {
|
|
if (move.from === ROOKS[us][i].square &&
|
|
this._castling[us] & ROOKS[us][i].flag) {
|
|
this._castling[us] ^= ROOKS[us][i].flag;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// turn off castling if we capture a rook
|
|
if (this._castling[them]) {
|
|
for (let i = 0, len = ROOKS[them].length; i < len; i++) {
|
|
if (move.to === ROOKS[them][i].square &&
|
|
this._castling[them] & ROOKS[them][i].flag) {
|
|
this._castling[them] ^= ROOKS[them][i].flag;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
this._hash ^= this._castlingKey();
|
|
// if big pawn move, update the en passant square
|
|
if (move.flags & BITS.BIG_PAWN) {
|
|
let epSquare;
|
|
if (us === BLACK) {
|
|
epSquare = move.to - 16;
|
|
}
|
|
else {
|
|
epSquare = move.to + 16;
|
|
}
|
|
if ((!((move.to - 1) & 0x88) &&
|
|
this._board[move.to - 1]?.type === PAWN &&
|
|
this._board[move.to - 1]?.color === them) ||
|
|
(!((move.to + 1) & 0x88) &&
|
|
this._board[move.to + 1]?.type === PAWN &&
|
|
this._board[move.to + 1]?.color === them)) {
|
|
this._epSquare = epSquare;
|
|
this._hash ^= this._epKey();
|
|
}
|
|
else {
|
|
this._epSquare = EMPTY;
|
|
}
|
|
}
|
|
else {
|
|
this._epSquare = EMPTY;
|
|
}
|
|
// reset the 50 move counter if a pawn is moved or a piece is captured
|
|
if (move.piece === PAWN) {
|
|
this._halfMoves = 0;
|
|
}
|
|
else if (move.flags & (BITS.CAPTURE | BITS.EP_CAPTURE)) {
|
|
this._halfMoves = 0;
|
|
}
|
|
else {
|
|
this._halfMoves++;
|
|
}
|
|
if (us === BLACK) {
|
|
this._moveNumber++;
|
|
}
|
|
this._turn = them;
|
|
this._hash ^= SIDE_KEY;
|
|
}
|
|
undo() {
|
|
const hash = this._hash;
|
|
const move = this._undoMove();
|
|
if (move) {
|
|
const prettyMove = new Move(this, move);
|
|
this._decPositionCount(hash);
|
|
return prettyMove;
|
|
}
|
|
return null;
|
|
}
|
|
_undoMove() {
|
|
const old = this._history.pop();
|
|
if (old === undefined) {
|
|
return null;
|
|
}
|
|
this._hash ^= this._epKey();
|
|
this._hash ^= this._castlingKey();
|
|
const move = old.move;
|
|
this._kings = old.kings;
|
|
this._turn = old.turn;
|
|
this._castling = old.castling;
|
|
this._epSquare = old.epSquare;
|
|
this._halfMoves = old.halfMoves;
|
|
this._moveNumber = old.moveNumber;
|
|
this._hash ^= this._epKey();
|
|
this._hash ^= this._castlingKey();
|
|
this._hash ^= SIDE_KEY;
|
|
const us = this._turn;
|
|
const them = swapColor(us);
|
|
if (move.flags & BITS.NULL_MOVE) {
|
|
return move;
|
|
}
|
|
this._movePiece(move.to, move.from);
|
|
// to undo any promotions
|
|
if (move.piece) {
|
|
this._clear(move.from);
|
|
this._set(move.from, { type: move.piece, color: us });
|
|
}
|
|
if (move.captured) {
|
|
if (move.flags & BITS.EP_CAPTURE) {
|
|
// en passant capture
|
|
let index;
|
|
if (us === BLACK) {
|
|
index = move.to - 16;
|
|
}
|
|
else {
|
|
index = move.to + 16;
|
|
}
|
|
this._set(index, { type: PAWN, color: them });
|
|
}
|
|
else {
|
|
// regular capture
|
|
this._set(move.to, { type: move.captured, color: them });
|
|
}
|
|
}
|
|
if (move.flags & (BITS.KSIDE_CASTLE | BITS.QSIDE_CASTLE)) {
|
|
let castlingTo, castlingFrom;
|
|
if (move.flags & BITS.KSIDE_CASTLE) {
|
|
castlingTo = move.to + 1;
|
|
castlingFrom = move.to - 1;
|
|
}
|
|
else {
|
|
castlingTo = move.to - 2;
|
|
castlingFrom = move.to + 1;
|
|
}
|
|
this._movePiece(castlingFrom, castlingTo);
|
|
}
|
|
return move;
|
|
}
|
|
pgn({ newline = '\n', maxWidth = 0, } = {}) {
|
|
/*
|
|
* using the specification from http://www.chessclub.com/help/PGN-spec
|
|
* example for html usage: .pgn({ max_width: 72, newline_char: "<br />" })
|
|
*/
|
|
const result = [];
|
|
let headerExists = false;
|
|
/* add the PGN header information */
|
|
for (const i in this._header) {
|
|
/*
|
|
* TODO: order of enumerated properties in header object is not
|
|
* guaranteed, see ECMA-262 spec (section 12.6.4)
|
|
*
|
|
* By using HEADER_TEMPLATE, the order of tags should be preserved; we
|
|
* do have to check for null placeholders, though, and omit them
|
|
*/
|
|
const headerTag = this._header[i];
|
|
if (headerTag)
|
|
result.push(`[${i} "${this._header[i]}"]` + newline);
|
|
headerExists = true;
|
|
}
|
|
if (headerExists && this._history.length) {
|
|
result.push(newline);
|
|
}
|
|
const appendComment = (moveString) => {
|
|
const comment = this._comments[this.fen()];
|
|
if (typeof comment !== 'undefined') {
|
|
const delimiter = moveString.length > 0 ? ' ' : '';
|
|
moveString = `${moveString}${delimiter}{${comment}}`;
|
|
}
|
|
return moveString;
|
|
};
|
|
// pop all of history onto reversed_history
|
|
const reversedHistory = [];
|
|
while (this._history.length > 0) {
|
|
reversedHistory.push(this._undoMove());
|
|
}
|
|
const moves = [];
|
|
let moveString = '';
|
|
// special case of a commented starting position with no moves
|
|
if (reversedHistory.length === 0) {
|
|
moves.push(appendComment(''));
|
|
}
|
|
// build the list of moves. a move_string looks like: "3. e3 e6"
|
|
while (reversedHistory.length > 0) {
|
|
moveString = appendComment(moveString);
|
|
const move = reversedHistory.pop();
|
|
// make TypeScript stop complaining about move being undefined
|
|
if (!move) {
|
|
break;
|
|
}
|
|
// if the position started with black to move, start PGN with #. ...
|
|
if (!this._history.length && move.color === 'b') {
|
|
const prefix = `${this._moveNumber}. ...`;
|
|
// is there a comment preceding the first move?
|
|
moveString = moveString ? `${moveString} ${prefix}` : prefix;
|
|
}
|
|
else if (move.color === 'w') {
|
|
// store the previous generated move_string if we have one
|
|
if (moveString.length) {
|
|
moves.push(moveString);
|
|
}
|
|
moveString = this._moveNumber + '.';
|
|
}
|
|
moveString =
|
|
moveString + ' ' + this._moveToSan(move, this._moves({ legal: true }));
|
|
this._makeMove(move);
|
|
}
|
|
// are there any other leftover moves?
|
|
if (moveString.length) {
|
|
moves.push(appendComment(moveString));
|
|
}
|
|
// is there a result? (there ALWAYS has to be a result according to spec; see Seven Tag Roster)
|
|
moves.push(this._header.Result || '*');
|
|
/*
|
|
* history should be back to what it was before we started generating PGN,
|
|
* so join together moves
|
|
*/
|
|
if (maxWidth === 0) {
|
|
return result.join('') + moves.join(' ');
|
|
}
|
|
// TODO (jah): huh?
|
|
const strip = function () {
|
|
if (result.length > 0 && result[result.length - 1] === ' ') {
|
|
result.pop();
|
|
return true;
|
|
}
|
|
return false;
|
|
};
|
|
// NB: this does not preserve comment whitespace.
|
|
const wrapComment = function (width, move) {
|
|
for (const token of move.split(' ')) {
|
|
if (!token) {
|
|
continue;
|
|
}
|
|
if (width + token.length > maxWidth) {
|
|
while (strip()) {
|
|
width--;
|
|
}
|
|
result.push(newline);
|
|
width = 0;
|
|
}
|
|
result.push(token);
|
|
width += token.length;
|
|
result.push(' ');
|
|
width++;
|
|
}
|
|
if (strip()) {
|
|
width--;
|
|
}
|
|
return width;
|
|
};
|
|
// wrap the PGN output at max_width
|
|
let currentWidth = 0;
|
|
for (let i = 0; i < moves.length; i++) {
|
|
if (currentWidth + moves[i].length > maxWidth) {
|
|
if (moves[i].includes('{')) {
|
|
currentWidth = wrapComment(currentWidth, moves[i]);
|
|
continue;
|
|
}
|
|
}
|
|
// if the current move will push past max_width
|
|
if (currentWidth + moves[i].length > maxWidth && i !== 0) {
|
|
// don't end the line with whitespace
|
|
if (result[result.length - 1] === ' ') {
|
|
result.pop();
|
|
}
|
|
result.push(newline);
|
|
currentWidth = 0;
|
|
}
|
|
else if (i !== 0) {
|
|
result.push(' ');
|
|
currentWidth++;
|
|
}
|
|
result.push(moves[i]);
|
|
currentWidth += moves[i].length;
|
|
}
|
|
return result.join('');
|
|
}
|
|
/**
|
|
* @deprecated Use `setHeader` and `getHeaders` instead. This method will return null header tags (which is not what you want)
|
|
*/
|
|
header(...args) {
|
|
for (let i = 0; i < args.length; i += 2) {
|
|
if (typeof args[i] === 'string' && typeof args[i + 1] === 'string') {
|
|
this._header[args[i]] = args[i + 1];
|
|
}
|
|
}
|
|
return this._header;
|
|
}
|
|
// TODO: value validation per spec
|
|
setHeader(key, value) {
|
|
this._header[key] = value ?? SEVEN_TAG_ROSTER[key] ?? null;
|
|
return this.getHeaders();
|
|
}
|
|
removeHeader(key) {
|
|
if (key in this._header) {
|
|
this._header[key] = SEVEN_TAG_ROSTER[key] || null;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
// return only non-null headers (omit placemarker nulls)
|
|
getHeaders() {
|
|
const nonNullHeaders = {};
|
|
for (const [key, value] of Object.entries(this._header)) {
|
|
if (value !== null) {
|
|
nonNullHeaders[key] = value;
|
|
}
|
|
}
|
|
return nonNullHeaders;
|
|
}
|
|
loadPgn(pgn, { strict = false, newlineChar = '\r?\n', } = {}) {
|
|
// If newlineChar is not the default, replace all instances with \n
|
|
if (newlineChar !== '\r?\n') {
|
|
pgn = pgn.replace(new RegExp(newlineChar, 'g'), '\n');
|
|
}
|
|
const parsedPgn = peg$parse(pgn);
|
|
// Put the board in the starting position
|
|
this.reset();
|
|
// parse PGN header
|
|
const headers = parsedPgn.headers;
|
|
let fen = '';
|
|
for (const key in headers) {
|
|
// check to see user is including fen (possibly with wrong tag case)
|
|
if (key.toLowerCase() === 'fen') {
|
|
fen = headers[key];
|
|
}
|
|
this.header(key, headers[key]);
|
|
}
|
|
/*
|
|
* the permissive parser should attempt to load a fen tag, even if it's the
|
|
* wrong case and doesn't include a corresponding [SetUp "1"] tag
|
|
*/
|
|
if (!strict) {
|
|
if (fen) {
|
|
this.load(fen, { preserveHeaders: true });
|
|
}
|
|
}
|
|
else {
|
|
/*
|
|
* strict parser - load the starting position indicated by [Setup '1']
|
|
* and [FEN position]
|
|
*/
|
|
if (headers['SetUp'] === '1') {
|
|
if (!('FEN' in headers)) {
|
|
throw new Error('Invalid PGN: FEN tag must be supplied with SetUp tag');
|
|
}
|
|
// don't clear the headers when loading
|
|
this.load(headers['FEN'], { preserveHeaders: true });
|
|
}
|
|
}
|
|
let node = parsedPgn.root;
|
|
while (node) {
|
|
if (node.move) {
|
|
const move = this._moveFromSan(node.move, strict);
|
|
if (move == null) {
|
|
throw new Error(`Invalid move in PGN: ${node.move}`);
|
|
}
|
|
else {
|
|
this._makeMove(move);
|
|
this._incPositionCount();
|
|
}
|
|
}
|
|
if (node.comment !== undefined) {
|
|
this._comments[this.fen()] = node.comment;
|
|
}
|
|
node = node.variations[0];
|
|
}
|
|
/*
|
|
* Per section 8.2.6 of the PGN spec, the Result tag pair must match match
|
|
* the termination marker. Only do this when headers are present, but the
|
|
* result tag is missing
|
|
*/
|
|
const result = parsedPgn.result;
|
|
if (result &&
|
|
Object.keys(this._header).length &&
|
|
this._header['Result'] !== result) {
|
|
this.setHeader('Result', result);
|
|
}
|
|
}
|
|
/*
|
|
* Convert a move from 0x88 coordinates to Standard Algebraic Notation
|
|
* (SAN)
|
|
*
|
|
* @param {boolean} strict Use the strict SAN parser. It will throw errors
|
|
* on overly disambiguated moves (see below):
|
|
*
|
|
* r1bqkbnr/ppp2ppp/2n5/1B1pP3/4P3/8/PPPP2PP/RNBQK1NR b KQkq - 2 4
|
|
* 4. ... Nge7 is overly disambiguated because the knight on c6 is pinned
|
|
* 4. ... Ne7 is technically the valid SAN
|
|
*/
|
|
_moveToSan(move, moves) {
|
|
let output = '';
|
|
if (move.flags & BITS.KSIDE_CASTLE) {
|
|
output = 'O-O';
|
|
}
|
|
else if (move.flags & BITS.QSIDE_CASTLE) {
|
|
output = 'O-O-O';
|
|
}
|
|
else if (move.flags & BITS.NULL_MOVE) {
|
|
return SAN_NULLMOVE;
|
|
}
|
|
else {
|
|
if (move.piece !== PAWN) {
|
|
const disambiguator = getDisambiguator(move, moves);
|
|
output += move.piece.toUpperCase() + disambiguator;
|
|
}
|
|
if (move.flags & (BITS.CAPTURE | BITS.EP_CAPTURE)) {
|
|
if (move.piece === PAWN) {
|
|
output += algebraic(move.from)[0];
|
|
}
|
|
output += 'x';
|
|
}
|
|
output += algebraic(move.to);
|
|
if (move.promotion) {
|
|
output += '=' + move.promotion.toUpperCase();
|
|
}
|
|
}
|
|
this._makeMove(move);
|
|
if (this.isCheck()) {
|
|
if (this.isCheckmate()) {
|
|
output += '#';
|
|
}
|
|
else {
|
|
output += '+';
|
|
}
|
|
}
|
|
this._undoMove();
|
|
return output;
|
|
}
|
|
// convert a move from Standard Algebraic Notation (SAN) to 0x88 coordinates
|
|
_moveFromSan(move, strict = false) {
|
|
// strip off any move decorations: e.g Nf3+?! becomes Nf3
|
|
let cleanMove = strippedSan(move);
|
|
if (!strict) {
|
|
if (cleanMove === '0-0') {
|
|
cleanMove = 'O-O';
|
|
}
|
|
else if (cleanMove === '0-0-0') {
|
|
cleanMove = 'O-O-O';
|
|
}
|
|
}
|
|
//first implementation of null with a dummy move (black king moves from a8 to a8), maybe this can be implemented better
|
|
if (cleanMove == SAN_NULLMOVE) {
|
|
const res = {
|
|
color: this._turn,
|
|
from: 0,
|
|
to: 0,
|
|
piece: 'k',
|
|
flags: BITS.NULL_MOVE,
|
|
};
|
|
return res;
|
|
}
|
|
let pieceType = inferPieceType(cleanMove);
|
|
let moves = this._moves({ legal: true, piece: pieceType });
|
|
// strict parser
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
if (cleanMove === strippedSan(this._moveToSan(moves[i], moves))) {
|
|
return moves[i];
|
|
}
|
|
}
|
|
// the strict parser failed
|
|
if (strict) {
|
|
return null;
|
|
}
|
|
let piece = undefined;
|
|
let matches = undefined;
|
|
let from = undefined;
|
|
let to = undefined;
|
|
let promotion = undefined;
|
|
/*
|
|
* The default permissive (non-strict) parser allows the user to parse
|
|
* non-standard chess notations. This parser is only run after the strict
|
|
* Standard Algebraic Notation (SAN) parser has failed.
|
|
*
|
|
* When running the permissive parser, we'll run a regex to grab the piece, the
|
|
* to/from square, and an optional promotion piece. This regex will
|
|
* parse common non-standard notation like: Pe2-e4, Rc1c4, Qf3xf7,
|
|
* f7f8q, b1c3
|
|
*
|
|
* NOTE: Some positions and moves may be ambiguous when using the permissive
|
|
* parser. For example, in this position: 6k1/8/8/B7/8/8/8/BN4K1 w - - 0 1,
|
|
* the move b1c3 may be interpreted as Nc3 or B1c3 (a disambiguated bishop
|
|
* move). In these cases, the permissive parser will default to the most
|
|
* basic interpretation (which is b1c3 parsing to Nc3).
|
|
*/
|
|
let overlyDisambiguated = false;
|
|
matches = cleanMove.match(/([pnbrqkPNBRQK])?([a-h][1-8])x?-?([a-h][1-8])([qrbnQRBN])?/);
|
|
if (matches) {
|
|
piece = matches[1];
|
|
from = matches[2];
|
|
to = matches[3];
|
|
promotion = matches[4];
|
|
if (from.length == 1) {
|
|
overlyDisambiguated = true;
|
|
}
|
|
}
|
|
else {
|
|
/*
|
|
* The [a-h]?[1-8]? portion of the regex below handles moves that may be
|
|
* overly disambiguated (e.g. Nge7 is unnecessary and non-standard when
|
|
* there is one legal knight move to e7). In this case, the value of
|
|
* 'from' variable will be a rank or file, not a square.
|
|
*/
|
|
matches = cleanMove.match(/([pnbrqkPNBRQK])?([a-h]?[1-8]?)x?-?([a-h][1-8])([qrbnQRBN])?/);
|
|
if (matches) {
|
|
piece = matches[1];
|
|
from = matches[2];
|
|
to = matches[3];
|
|
promotion = matches[4];
|
|
if (from.length == 1) {
|
|
overlyDisambiguated = true;
|
|
}
|
|
}
|
|
}
|
|
pieceType = inferPieceType(cleanMove);
|
|
moves = this._moves({
|
|
legal: true,
|
|
piece: piece ? piece : pieceType,
|
|
});
|
|
if (!to) {
|
|
return null;
|
|
}
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
if (!from) {
|
|
// if there is no from square, it could be just 'x' missing from a capture
|
|
if (cleanMove ===
|
|
strippedSan(this._moveToSan(moves[i], moves)).replace('x', '')) {
|
|
return moves[i];
|
|
}
|
|
// hand-compare move properties with the results from our permissive regex
|
|
}
|
|
else if ((!piece || piece.toLowerCase() == moves[i].piece) &&
|
|
Ox88[from] == moves[i].from &&
|
|
Ox88[to] == moves[i].to &&
|
|
(!promotion || promotion.toLowerCase() == moves[i].promotion)) {
|
|
return moves[i];
|
|
}
|
|
else if (overlyDisambiguated) {
|
|
/*
|
|
* SPECIAL CASE: we parsed a move string that may have an unneeded
|
|
* rank/file disambiguator (e.g. Nge7). The 'from' variable will
|
|
*/
|
|
const square = algebraic(moves[i].from);
|
|
if ((!piece || piece.toLowerCase() == moves[i].piece) &&
|
|
Ox88[to] == moves[i].to &&
|
|
(from == square[0] || from == square[1]) &&
|
|
(!promotion || promotion.toLowerCase() == moves[i].promotion)) {
|
|
return moves[i];
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
ascii() {
|
|
let s = ' +------------------------+\n';
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
// display the rank
|
|
if (file(i) === 0) {
|
|
s += ' ' + '87654321'[rank(i)] + ' |';
|
|
}
|
|
if (this._board[i]) {
|
|
const piece = this._board[i].type;
|
|
const color = this._board[i].color;
|
|
const symbol = color === WHITE ? piece.toUpperCase() : piece.toLowerCase();
|
|
s += ' ' + symbol + ' ';
|
|
}
|
|
else {
|
|
s += ' . ';
|
|
}
|
|
if ((i + 1) & 0x88) {
|
|
s += '|\n';
|
|
i += 8;
|
|
}
|
|
}
|
|
s += ' +------------------------+\n';
|
|
s += ' a b c d e f g h';
|
|
return s;
|
|
}
|
|
perft(depth) {
|
|
const moves = this._moves({ legal: false });
|
|
let nodes = 0;
|
|
const color = this._turn;
|
|
for (let i = 0, len = moves.length; i < len; i++) {
|
|
this._makeMove(moves[i]);
|
|
if (!this._isKingAttacked(color)) {
|
|
if (depth - 1 > 0) {
|
|
nodes += this.perft(depth - 1);
|
|
}
|
|
else {
|
|
nodes++;
|
|
}
|
|
}
|
|
this._undoMove();
|
|
}
|
|
return nodes;
|
|
}
|
|
setTurn(color) {
|
|
if (this._turn == color) {
|
|
return false;
|
|
}
|
|
this.move('--');
|
|
return true;
|
|
}
|
|
turn() {
|
|
return this._turn;
|
|
}
|
|
board() {
|
|
const output = [];
|
|
let row = [];
|
|
for (let i = Ox88.a8; i <= Ox88.h1; i++) {
|
|
if (this._board[i] == null) {
|
|
row.push(null);
|
|
}
|
|
else {
|
|
row.push({
|
|
square: algebraic(i),
|
|
type: this._board[i].type,
|
|
color: this._board[i].color,
|
|
});
|
|
}
|
|
if ((i + 1) & 0x88) {
|
|
output.push(row);
|
|
row = [];
|
|
i += 8;
|
|
}
|
|
}
|
|
return output;
|
|
}
|
|
squareColor(square) {
|
|
if (square in Ox88) {
|
|
const sq = Ox88[square];
|
|
return (rank(sq) + file(sq)) % 2 === 0 ? 'light' : 'dark';
|
|
}
|
|
return null;
|
|
}
|
|
history({ verbose = false } = {}) {
|
|
const reversedHistory = [];
|
|
const moveHistory = [];
|
|
while (this._history.length > 0) {
|
|
reversedHistory.push(this._undoMove());
|
|
}
|
|
while (true) {
|
|
const move = reversedHistory.pop();
|
|
if (!move) {
|
|
break;
|
|
}
|
|
if (verbose) {
|
|
moveHistory.push(new Move(this, move));
|
|
}
|
|
else {
|
|
moveHistory.push(this._moveToSan(move, this._moves()));
|
|
}
|
|
this._makeMove(move);
|
|
}
|
|
return moveHistory;
|
|
}
|
|
/*
|
|
* Keeps track of position occurrence counts for the purpose of repetition
|
|
* checking. Old positions are removed from the map if their counts are reduced to 0.
|
|
*/
|
|
_getPositionCount(hash) {
|
|
return this._positionCount.get(hash) ?? 0;
|
|
}
|
|
_incPositionCount() {
|
|
this._positionCount.set(this._hash, (this._positionCount.get(this._hash) ?? 0) + 1);
|
|
}
|
|
_decPositionCount(hash) {
|
|
const currentCount = this._positionCount.get(hash) ?? 0;
|
|
if (currentCount === 1) {
|
|
this._positionCount.delete(hash);
|
|
}
|
|
else {
|
|
this._positionCount.set(hash, currentCount - 1);
|
|
}
|
|
}
|
|
_pruneComments() {
|
|
const reversedHistory = [];
|
|
const currentComments = {};
|
|
const copyComment = (fen) => {
|
|
if (fen in this._comments) {
|
|
currentComments[fen] = this._comments[fen];
|
|
}
|
|
};
|
|
while (this._history.length > 0) {
|
|
reversedHistory.push(this._undoMove());
|
|
}
|
|
copyComment(this.fen());
|
|
while (true) {
|
|
const move = reversedHistory.pop();
|
|
if (!move) {
|
|
break;
|
|
}
|
|
this._makeMove(move);
|
|
copyComment(this.fen());
|
|
}
|
|
this._comments = currentComments;
|
|
}
|
|
getComment() {
|
|
return this._comments[this.fen()];
|
|
}
|
|
setComment(comment) {
|
|
this._comments[this.fen()] = comment.replace('{', '[').replace('}', ']');
|
|
}
|
|
/**
|
|
* @deprecated Renamed to `removeComment` for consistency
|
|
*/
|
|
deleteComment() {
|
|
return this.removeComment();
|
|
}
|
|
removeComment() {
|
|
const comment = this._comments[this.fen()];
|
|
delete this._comments[this.fen()];
|
|
return comment;
|
|
}
|
|
getComments() {
|
|
this._pruneComments();
|
|
return Object.keys(this._comments).map((fen) => {
|
|
return { fen: fen, comment: this._comments[fen] };
|
|
});
|
|
}
|
|
/**
|
|
* @deprecated Renamed to `removeComments` for consistency
|
|
*/
|
|
deleteComments() {
|
|
return this.removeComments();
|
|
}
|
|
removeComments() {
|
|
this._pruneComments();
|
|
return Object.keys(this._comments).map((fen) => {
|
|
const comment = this._comments[fen];
|
|
delete this._comments[fen];
|
|
return { fen: fen, comment: comment };
|
|
});
|
|
}
|
|
setCastlingRights(color, rights) {
|
|
for (const side of [KING, QUEEN]) {
|
|
if (rights[side] !== undefined) {
|
|
if (rights[side]) {
|
|
this._castling[color] |= SIDES[side];
|
|
}
|
|
else {
|
|
this._castling[color] &= ~SIDES[side];
|
|
}
|
|
}
|
|
}
|
|
this._updateCastlingRights();
|
|
const result = this.getCastlingRights(color);
|
|
return ((rights[KING] === undefined || rights[KING] === result[KING]) &&
|
|
(rights[QUEEN] === undefined || rights[QUEEN] === result[QUEEN]));
|
|
}
|
|
getCastlingRights(color) {
|
|
return {
|
|
[KING]: (this._castling[color] & SIDES[KING]) !== 0,
|
|
[QUEEN]: (this._castling[color] & SIDES[QUEEN]) !== 0,
|
|
};
|
|
}
|
|
moveNumber() {
|
|
return this._moveNumber;
|
|
}
|
|
}
|
|
|
|
exports.BISHOP = BISHOP;
|
|
exports.BLACK = BLACK;
|
|
exports.Chess = Chess;
|
|
exports.DEFAULT_POSITION = DEFAULT_POSITION;
|
|
exports.KING = KING;
|
|
exports.KNIGHT = KNIGHT;
|
|
exports.Move = Move;
|
|
exports.PAWN = PAWN;
|
|
exports.QUEEN = QUEEN;
|
|
exports.ROOK = ROOK;
|
|
exports.SEVEN_TAG_ROSTER = SEVEN_TAG_ROSTER;
|
|
exports.SQUARES = SQUARES;
|
|
exports.WHITE = WHITE;
|
|
exports.validateFen = validateFen;
|
|
exports.xoroshiro128 = xoroshiro128;
|
|
//# sourceMappingURL=chess.js.map
|