chess.min.js

/* @license
 * Copyright (c) 2017, Jeff Hlywa (jhlywa@gmail.com)
 * Released under the BSD license
 * https://github.com/jhlywa/chess.js/blob/master/LICENSE
 */
var Chess=function(r){function e(r){"undefined"==typeof r&&(r=!1),ar=new Array(128),lr={w:x,b:x},pr=U,sr={w:0,b:0},cr=x,vr=0,gr=1,hr=[],r||(dr={}),u(i())}function n(){t(H)}function t(r,n){"undefined"==typeof n&&(n=!1);var t=r.split(/\s+/),f=t[0],a=0;if(!o(r).valid)return!1;e(n);for(var p=0;p<f.length;p++){var s=f.charAt(p);if("/"===s)a+=8;else if(O(s))a+=parseInt(s,10);else{var c="a">s?U:Q;l({type:s.toLowerCase(),color:c},R(a)),a++}}return pr=t[1],t[2].indexOf("K")>-1&&(sr.w|=er.KSIDE_CASTLE),t[2].indexOf("Q")>-1&&(sr.w|=er.QSIDE_CASTLE),t[2].indexOf("k")>-1&&(sr.b|=er.KSIDE_CASTLE),t[2].indexOf("q")>-1&&(sr.b|=er.QSIDE_CASTLE),cr="-"===t[3]?x:fr[t[3]],vr=parseInt(t[4],10),gr=parseInt(t[5],10),u(i()),!0}function o(r){var e={0:"No errors.",1:"FEN string must contain six space-delimited fields.",2:"6th field (move number) must be a positive integer.",3:"5th field (half move counter) must be a non-negative integer.",4:"4th field (en-passant square) is invalid.",5:"3rd field (castling 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i=0,f=!1,u=0;u<t[o].length;u++)if(isNaN(t[o][u])){if(!/^[prnbqkPRNBQK]$/.test(t[o][u]))return{valid:!1,error_number:9,error:e[9]};i+=1,f=!1}else{if(f)return{valid:!1,error_number:8,error:e[8]};i+=parseInt(t[o][u],10),f=!0}if(8!==i)return{valid:!1,error_number:10,error:e[10]}}return"3"==n[3][1]&&"w"==n[1]||"6"==n[3][1]&&"b"==n[1]?{valid:!1,error_number:11,error:e[11]}:{valid:!0,error_number:0,error:e[0]}}function i(){for(var r=0,e="",n=fr.a8;n<=fr.h1;n++){if(null==ar[n])r++;else{r>0&&(e+=r,r=0);var t=ar[n].color,o=ar[n].type;e+=t===U?o.toUpperCase():o.toLowerCase()}n+1&136&&(r>0&&(e+=r),n!==fr.h1&&(e+="/"),r=0,n+=8)}var i="";sr[U]&er.KSIDE_CASTLE&&(i+="K"),sr[U]&er.QSIDE_CASTLE&&(i+="Q"),sr[Q]&er.KSIDE_CASTLE&&(i+="k"),sr[Q]&er.QSIDE_CASTLE&&(i+="q"),i=i||"-";var f=cr===x?"-":R(cr);return[e,pr,i,f,vr,gr].join(" ")}function f(r){for(var e=0;e<r.length;e+=2)"string"==typeof r[e]&&"string"==typeof r[e+1]&&(dr[r[e]]=r[e+1]);return dr}function 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r){if(!(r.square in fr))return[];f=u=fr[r.square],a=!0}for(var p=f;u>=p;p++)if(136&p)p+=7;else{var c=ar[p];if(null!=c&&c.color===t)if(c.type===j){var v=p+z[t][0];if(null==ar[v]){e(ar,n,p,v,er.NORMAL);var v=p+z[t][1];i[t]===w(p)&&null==ar[v]&&e(ar,n,p,v,er.BIG_PAWN)}for(g=2;4>g;g++){var v=p+z[t][g];136&v||(null!=ar[v]&&ar[v].color===o?e(ar,n,p,v,er.CAPTURE):v===cr&&e(ar,n,p,cr,er.EP_CAPTURE))}}else for(var g=0,E=J[c.type].length;E>g;g++)for(var b=J[c.type][g],v=p;;){if(v+=b,136&v)break;if(null!=ar[v]){if(ar[v].color===t)break;e(ar,n,p,v,er.CAPTURE);break}if(e(ar,n,p,v,er.NORMAL),"n"===c.type||"k"===c.type)break}}if(!a||u===lr[t]){if(sr[t]&er.KSIDE_CASTLE){var _=lr[t],y=_+2;null!=ar[_+1]||null!=ar[y]||h(o,lr[t])||h(o,_+1)||h(o,y)||e(ar,n,lr[t],y,er.KSIDE_CASTLE)}if(sr[t]&er.QSIDE_CASTLE){var _=lr[t],y=_-2;null!=ar[_-1]||null!=ar[_-2]||null!=ar[_-3]||h(o,lr[t])||h(o,_-1)||h(o,y)||e(ar,n,lr[t],y,er.QSIDE_CASTLE)}}if(!l)return n;for(var m=[],p=0,E=n.length;E>p;p++)S(n[p]),d(t)||m.push(n[p]),C();return m}function v(r,e){var n="";if(r.flags&er.KSIDE_CASTLE)n="O-O";else if(r.flags&er.QSIDE_CASTLE)n="O-O-O";else{var t=T(r,e);r.piece!==j&&(n+=r.piece.toUpperCase()+t),r.flags&(er.CAPTURE|er.EP_CAPTURE)&&(r.piece===j&&(n+=R(r.from)[0]),n+="x"),n+=R(r.to),r.flags&er.PROMOTION&&(n+="="+r.promotion.toUpperCase())}return S(r),E()&&(n+=b()?"#":"+"),C(),n}function g(r){return r.replace(/=/,"").replace(/[+#]?[?!]*$/,"")}function h(r,e){for(var n=fr.a8;n<=fr.h1;n++)if(136&n)n+=7;else if(null!=ar[n]&&ar[n].color===r){var t=ar[n],o=n-e,i=o+119;if(V[i]&1<<Y[t.type]){if(t.type===j){if(o>0){if(t.color===U)return!0}else if(t.color===Q)return!0;continue}if("n"===t.type||"k"===t.type)return!0;for(var f=X[i],u=n+f,a=!1;u!==e;){if(null!=ar[u]){a=!0;break}u+=f}if(!a)return!0}}return!1}function d(r){return h(N(r),lr[r])}function E(){return d(pr)}function b(){return E()&&0===c().length}function _(){return!E()&&0===c().length}function y(){for(var r={},e=[],n=0,t=0,o=fr.a8;o<=fr.h1;o++)if(t=(t+1)%2,136&o)o+=7;else{var i=ar[o];i&&(r[i.type]=i.type in r?r[i.type]+1:1,i.type===$&&e.push(t),n++)}if(2===n)return!0;if(3===n&&(1===r[$]||1===r[B]))return!0;if(n===r[$]+2){for(var f=0,u=e.length,o=0;u>o;o++)f+=e[o];if(0===f||f===u)return!0}return!1}function m(){for(var r=[],e={},n=!1;;){var t=C();if(!t)break;r.push(t)}for(;;){var o=i().split(" ").slice(0,4).join(" ");if(e[o]=o in e?e[o]+1:1,e[o]>=3&&(n=!0),!r.length)break;S(r.pop())}return n}function A(r){hr.push({move:r,kings:{b:lr.b,w:lr.w},turn:pr,castling:{b:sr.b,w:sr.w},ep_square:cr,half_moves:vr,move_number:gr})}function S(r){var e=pr,n=N(e);if(A(r),ar[r.to]=ar[r.from],ar[r.from]=null,r.flags&er.EP_CAPTURE&&(pr===Q?ar[r.to-16]=null:ar[r.to+16]=null),r.flags&er.PROMOTION&&(ar[r.to]={type:r.promotion,color:e}),ar[r.to].type===F){if(lr[ar[r.to].color]=r.to,r.flags&er.KSIDE_CASTLE){var t=r.to-1,o=r.to+1;ar[t]=ar[o],ar[o]=null}else if(r.flags&er.QSIDE_CASTLE){var t=r.to+1,o=r.to-2;ar[t]=ar[o],ar[o]=null}sr[e]=""}if(sr[e])for(var i=0,f=ur[e].length;f>i;i++)if(r.from===ur[e][i].square&&sr[e]&ur[e][i].flag){sr[e]^=ur[e][i].flag;break}if(sr[n])for(var i=0,f=ur[n].length;f>i;i++)if(r.to===ur[n][i].square&&sr[n]&ur[n][i].flag){sr[n]^=ur[n][i].flag;break}cr=r.flags&er.BIG_PAWN?"b"===pr?r.to-16:r.to+16:x,r.piece===j?vr=0:r.flags&(er.CAPTURE|er.EP_CAPTURE)?vr=0:vr++,pr===Q&&gr++,pr=N(pr)}function C(){var r=hr.pop();if(null==r)return null;var e=r.move;lr=r.kings,pr=r.turn,sr=r.castling,cr=r.ep_square,vr=r.half_moves,gr=r.move_number;var n=pr,t=N(pr);if(ar[e.from]=ar[e.to],ar[e.from].type=e.piece,ar[e.to]=null,e.flags&er.CAPTURE)ar[e.to]={type:e.captured,color:t};else if(e.flags&er.EP_CAPTURE){var o;o=n===Q?e.to-16:e.to+16,ar[o]={type:j,color:t}}if(e.flags&(er.KSIDE_CASTLE|er.QSIDE_CASTLE)){var i,f;e.flags&er.KSIDE_CASTLE?(i=e.to+1,f=e.to-1):e.flags&er.QSIDE_CASTLE&&(i=e.to-2,f=e.to+1),ar[i]=ar[f],ar[f]=null}return e}function T(r,e){for(var 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