git.sesse.net Git - remoteglot/blob - www/js/remoteglot.js

   1 (function() {
   2
   3 /** @type {window.ChessBoard} @private */
   4 var board = null;
   5
   6 /**
   7  * The most recent analysis data we have from the server
   8  * (about the most recent position).
   9  *
  10  * @type {?Object}
  11  * @private */
  12 var current_analysis_data = null;
  13
  14 /**
  15  * If we are displaying previous analysis, this is non-null,
  16  * and will override most of current_analysis_data.
  17  *
  18  * @type {?Object}
  19  * @private
  20  */
  21 var displayed_analysis_data = null;
  22
  23 /** @type {Array.<{
  24  *      from_col: number,
  25  *      from_row: number,
  26  *      to_col: number,
  27  *      to_row: number,
  28  *      line_width: number,
  29  *      arrow_size: number,
  30  *      fg_color: string
  31  * }>}
  32  * @private
  33  */
  34 var arrows = [];
  35
  36 /** @type {Array.<Array.<boolean>>} */
  37 var occupied_by_arrows = [];
  38
  39 var refutation_lines = [];
  40
  41 /** @type {!number} @private */
  42 var move_num = 1;
  43
  44 /** @type {!string} @private */
  45 var toplay = 'W';
  46
  47 /** @type {number} @private */
  48 var ims = 0;
  49
  50 /** @type {boolean} @private */
  51 var sort_refutation_lines_by_score = true;
  52
  53 /** @type {boolean} @private */
  54 var truncate_display_history = true;
  55
  56 /** @type {!string|undefined} @private */
  57 var highlight_from = undefined;
  58
  59 /** @type {!string|undefined} @private */
  60 var highlight_to = undefined;
  61
  62 /** @type {?jQuery} @private */
  63 var highlighted_move = null;
  64
  65 /** @type {?number} @private */
  66 var unique = null;
  67
  68 /** @type {boolean} @private */
  69 var enable_sound = false;
  70
  71 /**
  72  * Our best estimate of how many milliseconds we need to add to
  73  * new Date() to get the true UTC time. Calibrated against the
  74  * server clock.
  75  *
  76  * @type {?number}
  77  * @private
  78  */
  79 var client_clock_offset_ms = null;
  80
  81 var clock_timer = null;
  82
  83 /** The current position on the board, represented as a FEN string.
  84  * @type {?string}
  85  * @private
  86  */
  87 var fen = null;
  88
  89 /** @typedef {{
  90  *    start_fen: string,
  91  *    uci_pv: Array.<string>,
  92  *    pretty_pv: Array.<string>,
  93  *    line_num: number
  94  * }} DisplayLine
  95  */
  96
  97 /** @type {Array.<DisplayLine>}
  98  * @private
  99  */
 100 var display_lines = [];
 101
 102 /** @type {?DisplayLine} @private */
 103 var current_display_line = null;
 104
 105 /** @type {boolean} @private */
 106 var current_display_line_is_history = false;
 107
 108 /** @type {?number} @private */
 109 var current_display_move = null;
 110
 111 var supports_html5_storage = function() {
 112         try {
 113                 return 'localStorage' in window && window['localStorage'] !== null;
 114         } catch (e) {
 115                 return false;
 116         }
 117 }
 118
 119 // Make the unique token persistent so people refreshing the page won't count twice.
 120 // Of course, you can never fully protect against people deliberately wanting to spam.
 121 var get_unique = function() {
 122         var use_local_storage = supports_html5_storage();
 123         if (use_local_storage && localStorage['unique']) {
 124                 return localStorage['unique'];
 125         }
 126         var unique = Math.random();
 127         if (use_local_storage) {
 128                 localStorage['unique'] = unique;
 129         }
 130         return unique;
 131 }
 132
 133 var request_update = function() {
 134         $.ajax({
 135                 url: "/analysis.pl?ims=" + ims + "&unique=" + unique
 136         }).done(function(data, textstatus, xhr) {
 137                 sync_server_clock(xhr.getResponseHeader('Date'));
 138                 ims = xhr.getResponseHeader('X-RGLM');
 139                 var num_viewers = xhr.getResponseHeader('X-RGNV');
 140                 var new_data;
 141                 if (Array.isArray(data)) {
 142                         new_data = JSON.parse(JSON.stringify(current_analysis_data));
 143                         JSON_delta.patch(new_data, data);
 144                 } else {
 145                         new_data = data;
 146                 }
 147                 possibly_play_sound(current_analysis_data, new_data);
 148                 current_analysis_data = new_data;
 149                 update_board(current_analysis_data, displayed_analysis_data);
 150                 update_num_viewers(num_viewers);
 151
 152                 // Next update.
 153                 setTimeout(function() { request_update(); }, 100);
 154         }).fail(function() {
 155                 // Wait ten seconds, then try again.
 156                 setTimeout(function() { request_update(); }, 10000);
 157         });
 158 }
 159
 160 var possibly_play_sound = function(old_data, new_data) {
 161         if (!enable_sound) {
 162                 return;
 163         }
 164         if (old_data === null) {
 165                 return;
 166         }
 167         var ding = document.getElementById('ding');
 168         if (ding && ding.play) {
 169                 if (old_data['position'] && old_data['position']['fen'] &&
 170                     new_data['position'] && new_data['position']['fen'] &&
 171                     (old_data['position']['fen'] !== new_data['position']['fen'] ||
 172                      old_data['position']['move_num'] !== new_data['position']['move_num'])) {
 173                         ding.play();
 174                 }
 175         }
 176 }
 177
 178 /**
 179  * @type {!string} server_date_string
 180  */
 181 var sync_server_clock = function(server_date_string) {
 182         var server_time_ms = new Date(server_date_string).getTime();
 183         var client_time_ms = new Date().getTime();
 184         var estimated_offset_ms = server_time_ms - client_time_ms;
 185
 186         // In order not to let the noise move us too much back and forth
 187         // (the server only has one-second resolution anyway), we only
 188         // change an existing skew if we are at least five seconds off.
 189         if (client_clock_offset_ms === null ||
 190             Math.abs(estimated_offset_ms - client_clock_offset_ms) > 5000) {
 191                 client_clock_offset_ms = estimated_offset_ms;
 192         }
 193 }
 194
 195 var clear_arrows = function() {
 196         for (var i = 0; i < arrows.length; ++i) {
 197                 if (arrows[i].svg) {
 198                         arrows[i].svg.parentElement.removeChild(arrows[i].svg);
 199                         delete arrows[i].svg;
 200                 }
 201         }
 202         arrows = [];
 203
 204         occupied_by_arrows = [];
 205         for (var y = 0; y < 8; ++y) {
 206                 occupied_by_arrows.push([false, false, false, false, false, false, false, false]);
 207         }
 208 }
 209
 210 var redraw_arrows = function() {
 211         for (var i = 0; i < arrows.length; ++i) {
 212                 position_arrow(arrows[i]);
 213         }
 214 }
 215
 216 /** @param {!number} x
 217  * @return {!number}
 218  */
 219 var sign = function(x) {
 220         if (x > 0) {
 221                 return 1;
 222         } else if (x < 0) {
 223                 return -1;
 224         } else {
 225                 return 0;
 226         }
 227 }
 228
 229 /** See if drawing this arrow on the board would cause unduly amount of confusion.
 230  * @param {!string} from The square the arrow is from (e.g. e4).
 231  * @param {!string} to The square the arrow is to (e.g. e4).
 232  * @return {boolean}
 233  */
 234 var interfering_arrow = function(from, to) {
 235         var from_col = from.charCodeAt(0) - "a1".charCodeAt(0);
 236         var from_row = from.charCodeAt(1) - "a1".charCodeAt(1);
 237         var to_col   = to.charCodeAt(0) - "a1".charCodeAt(0);
 238         var to_row   = to.charCodeAt(1) - "a1".charCodeAt(1);
 239
 240         occupied_by_arrows[from_row][from_col] = true;
 241
 242         // Knight move: Just check that we haven't been at the destination before.
 243         if ((Math.abs(to_col - from_col) == 2 && Math.abs(to_row - from_row) == 1) ||
 244             (Math.abs(to_col - from_col) == 1 && Math.abs(to_row - from_row) == 2)) {
 245                 return occupied_by_arrows[to_row][to_col];
 246         }
 247
 248         // Sliding piece: Check if anything except the from-square is seen before.
 249         var dx = sign(to_col - from_col);
 250         var dy = sign(to_row - from_row);
 251         var x = from_col;
 252         var y = from_row;
 253         do {
 254                 x += dx;
 255                 y += dy;
 256                 if (occupied_by_arrows[y][x]) {
 257                         return true;
 258                 }
 259                 occupied_by_arrows[y][x] = true;
 260         } while (x != to_col || y != to_row);
 261
 262         return false;
 263 }
 264
 265 /** Find a point along the coordinate system given by the given line,
 266  * <t> units forward from the start of the line, <u> units to the right of it.
 267  * @param {!number} x1
 268  * @param {!number} x2
 269  * @param {!number} y1
 270  * @param {!number} y2
 271  * @param {!number} t
 272  * @param {!number} u
 273  * @return {!string} The point in "x y" form, suitable for SVG paths.
 274  */
 275 var point_from_start = function(x1, y1, x2, y2, t, u) {
 276         var dx = x2 - x1;
 277         var dy = y2 - y1;
 278
 279         var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
 280         dx *= norm;
 281         dy *= norm;
 282
 283         var x = x1 + dx * t + dy * u;
 284         var y = y1 + dy * t - dx * u;
 285         return x + " " + y;
 286 }
 287
 288 /** Find a point along the coordinate system given by the given line,
 289  * <t> units forward from the end of the line, <u> units to the right of it.
 290  * @param {!number} x1
 291  * @param {!number} x2
 292  * @param {!number} y1
 293  * @param {!number} y2
 294  * @param {!number} t
 295  * @param {!number} u
 296  * @return {!string} The point in "x y" form, suitable for SVG paths.
 297  */
 298 var point_from_end = function(x1, y1, x2, y2, t, u) {
 299         var dx = x2 - x1;
 300         var dy = y2 - y1;
 301
 302         var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
 303         dx *= norm;
 304         dy *= norm;
 305
 306         var x = x2 + dx * t + dy * u;
 307         var y = y2 + dy * t - dx * u;
 308         return x + " " + y;
 309 }
 310
 311 var position_arrow = function(arrow) {
 312         if (arrow.svg) {
 313                 arrow.svg.parentElement.removeChild(arrow.svg);
 314                 delete arrow.svg;
 315         }
 316         if (current_display_line !== null && !current_display_line_is_history) {
 317                 return;
 318         }
 319
 320         var pos = $(".square-a8").position();
 321
 322         var zoom_factor = $("#board").width() / 400.0;
 323         var line_width = arrow.line_width * zoom_factor;
 324         var arrow_size = arrow.arrow_size * zoom_factor;
 325
 326         var square_width = $(".square-a8").width();
 327         var from_y = (7 - arrow.from_row + 0.5)*square_width;
 328         var to_y = (7 - arrow.to_row + 0.5)*square_width;
 329         var from_x = (arrow.from_col + 0.5)*square_width;
 330         var to_x = (arrow.to_col + 0.5)*square_width;
 331
 332         var SVG_NS = "http://www.w3.org/2000/svg";
 333         var XHTML_NS = "http://www.w3.org/1999/xhtml";
 334         var svg = document.createElementNS(SVG_NS, "svg");
 335         svg.setAttribute("width", /** @type{number} */ ($("#board").width()));
 336         svg.setAttribute("height", /** @type{number} */ ($("#board").height()));
 337         svg.setAttribute("style", "position: absolute");
 338         svg.setAttribute("position", "absolute");
 339         svg.setAttribute("version", "1.1");
 340         svg.setAttribute("class", "c1");
 341         svg.setAttribute("xmlns", XHTML_NS);
 342
 343         var x1 = from_x;
 344         var y1 = from_y;
 345         var x2 = to_x;
 346         var y2 = to_y;
 347
 348         // Draw the line.
 349         var outline = document.createElementNS(SVG_NS, "path");
 350         outline.setAttribute("d", "M " + point_from_start(x1, y1, x2, y2, arrow_size / 2, 0) + " L " + point_from_end(x1, y1, x2, y2, -arrow_size / 2, 0));
 351         outline.setAttribute("xmlns", XHTML_NS);
 352         outline.setAttribute("stroke", "#666");
 353         outline.setAttribute("stroke-width", line_width + 2);
 354         outline.setAttribute("fill", "none");
 355         svg.appendChild(outline);
 356
 357         var path = document.createElementNS(SVG_NS, "path");
 358         path.setAttribute("d", "M " + point_from_start(x1, y1, x2, y2, arrow_size / 2, 0) + " L " + point_from_end(x1, y1, x2, y2, -arrow_size / 2, 0));
 359         path.setAttribute("xmlns", XHTML_NS);
 360         path.setAttribute("stroke", arrow.fg_color);
 361         path.setAttribute("stroke-width", line_width);
 362         path.setAttribute("fill", "none");
 363         svg.appendChild(path);
 364
 365         // Then the arrow head.
 366         var head = document.createElementNS(SVG_NS, "path");
 367         head.setAttribute("d",
 368                 "M " +  point_from_end(x1, y1, x2, y2, 0, 0) +
 369                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, -arrow_size / 2) +
 370                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size * .623, 0.0) +
 371                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, arrow_size / 2) +
 372                 " L " + point_from_end(x1, y1, x2, y2, 0, 0));
 373         head.setAttribute("xmlns", XHTML_NS);
 374         head.setAttribute("stroke", "#000");
 375         head.setAttribute("stroke-width", "1");
 376         head.setAttribute("fill", arrow.fg_color);
 377         svg.appendChild(head);
 378
 379         $(svg).css({ top: pos.top, left: pos.left });
 380         document.body.appendChild(svg);
 381         arrow.svg = svg;
 382 }
 383
 384 /**
 385  * @param {!string} from_square
 386  * @param {!string} to_square
 387  * @param {!string} fg_color
 388  * @param {number} line_width
 389  * @param {number} arrow_size
 390  */
 391 var create_arrow = function(from_square, to_square, fg_color, line_width, arrow_size) {
 392         var from_col = from_square.charCodeAt(0) - "a1".charCodeAt(0);
 393         var from_row = from_square.charCodeAt(1) - "a1".charCodeAt(1);
 394         var to_col   = to_square.charCodeAt(0) - "a1".charCodeAt(0);
 395         var to_row   = to_square.charCodeAt(1) - "a1".charCodeAt(1);
 396
 397         // Create arrow.
 398         var arrow = {
 399                 from_col: from_col,
 400                 from_row: from_row,
 401                 to_col: to_col,
 402                 to_row: to_row,
 403                 line_width: line_width,
 404                 arrow_size: arrow_size,
 405                 fg_color: fg_color
 406         };
 407
 408         position_arrow(arrow);
 409         arrows.push(arrow);
 410 }
 411
 412 var compare_by_sort_key = function(refutation_lines, a, b) {
 413         var ska = refutation_lines[a]['sort_key'];
 414         var skb = refutation_lines[b]['sort_key'];
 415         if (ska < skb) return -1;
 416         if (ska > skb) return 1;
 417         return 0;
 418 };
 419
 420 var compare_by_score = function(refutation_lines, a, b) {
 421         var sa = parseInt(refutation_lines[b]['score_sort_key'], 10);
 422         var sb = parseInt(refutation_lines[a]['score_sort_key'], 10);
 423         return sa - sb;
 424 }
 425
 426 /**
 427  * Fake multi-PV using the refutation lines. Find all “relevant” moves,
 428  * sorted by quality, descending.
 429  *
 430  * @param {!Object} data
 431  * @param {number} margin The maximum number of centipawns worse than the
 432  *     best move can be and still be included.
 433  * @return {Array.<string>} The UCI representation (e.g. e1g1) of all
 434  *     moves, in score order.
 435  */
 436 var find_nonstupid_moves = function(data, margin) {
 437         // First of all, if there are any moves that are more than 0.5 ahead of
 438         // the primary move, the refutation lines are probably bunk, so just
 439         // kill them all.
 440         var best_score = undefined;
 441         var pv_score = undefined;
 442         for (var move in data['refutation_lines']) {
 443                 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
 444                 if (move == data['pv_uci'][0]) {
 445                         pv_score = score;
 446                 }
 447                 if (best_score === undefined || score > best_score) {
 448                         best_score = score;
 449                 }
 450                 if (!(data['refutation_lines'][move]['depth'] >= 8)) {
 451                         return [];
 452                 }
 453         }
 454
 455         if (best_score - pv_score > 50) {
 456                 return [];
 457         }
 458
 459         // Now find all moves that are within “margin” of the best score.
 460         // The PV move will always be first.
 461         var moves = [];
 462         for (var move in data['refutation_lines']) {
 463                 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
 464                 if (move != data['pv_uci'][0] && best_score - score <= margin) {
 465                         moves.push(move);
 466                 }
 467         }
 468         moves = moves.sort(function(a, b) { return compare_by_score(data['refutation_lines'], a, b) });
 469         moves.unshift(data['pv_uci'][0]);
 470
 471         return moves;
 472 }
 473
 474 /**
 475  * @param {number} x
 476  * @return {!string}
 477  */
 478 var thousands = function(x) {
 479         return String(x).split('').reverse().join('').replace(/(\d{3}\B)/g, '$1,').split('').reverse().join('');
 480 }
 481
 482 /**
 483  * @param {!string} fen
 484  * @param {Array.<string>} pretty_pv
 485  * @param {number} move_num
 486  * @param {!string} toplay
 487  * @param {number=} opt_limit
 488  * @param {boolean=} opt_showlast
 489  */
 490 var add_pv = function(fen, pretty_pv, move_num, toplay, opt_limit, opt_showlast) {
 491         display_lines.push({
 492                 start_fen: fen,
 493                 pretty_pv: pretty_pv,
 494                 line_number: display_lines.length
 495         });
 496         return print_pv(display_lines.length - 1, pretty_pv, move_num, toplay, opt_limit, opt_showlast);
 497 }
 498
 499 /**
 500  * @param {number} line_num
 501  * @param {Array.<string>} pretty_pv
 502  * @param {number} move_num
 503  * @param {!string} toplay
 504  * @param {number=} opt_limit
 505  * @param {boolean=} opt_showlast
 506  */
 507 var print_pv = function(line_num, pretty_pv, move_num, toplay, opt_limit, opt_showlast) {
 508         var pv = '';
 509         var i = 0;
 510         if (opt_limit && opt_showlast && pretty_pv.length > opt_limit) {
 511                 // Truncate the PV at the beginning (instead of at the end).
 512                 // We assume here that toplay is 'W'. We also assume that if
 513                 // opt_showlast is set, then it is the history, and thus,
 514                 // the UI should be to expand the history.
 515                 pv = '(<a class="move" href="javascript:collapse_history(false)">…</a>) ';
 516                 i = pretty_pv.length - opt_limit;
 517                 if (i % 2 == 1) {
 518                         ++i;
 519                 }
 520                 move_num += i / 2;
 521         } else if (toplay == 'B' && pretty_pv.length > 0) {
 522                 var move = "<a class=\"move\" id=\"automove" + line_num + "-0\" href=\"javascript:show_line(" + line_num + ", " + 0 + ");\">" + pretty_pv[0] + "</a>";
 523                 pv = move_num + '. … ' + move;
 524                 toplay = 'W';
 525                 ++i;
 526                 ++move_num;
 527         }
 528         for ( ; i < pretty_pv.length; ++i) {
 529                 var move = "<a class=\"move\" id=\"automove" + line_num + "-" + i + "\" href=\"javascript:show_line(" + line_num + ", " + i + ");\">" + pretty_pv[i] + "</a>";
 530
 531                 if (toplay == 'W') {
 532                         if (i > opt_limit && !opt_showlast) {
 533                                 return pv + ' (…)';
 534                         }
 535                         if (pv != '') {
 536                                 pv += ' ';
 537                         }
 538                         pv += move_num + '. ' + move;
 539                         ++move_num;
 540                         toplay = 'B';
 541                 } else {
 542                         pv += ' ' + move;
 543                         toplay = 'W';
 544                 }
 545         }
 546         return pv;
 547 }
 548
 549 var update_highlight = function() {
 550         $("#board").find('.square-55d63').removeClass('nonuglyhighlight');
 551         if ((current_display_line === null || current_display_line_is_history) &&
 552             highlight_from !== undefined && highlight_to !== undefined) {
 553                 $("#board").find('.square-' + highlight_from).addClass('nonuglyhighlight');
 554                 $("#board").find('.square-' + highlight_to).addClass('nonuglyhighlight');
 555         }
 556 }
 557
 558 var update_history = function() {
 559         if (display_lines[0] === null || display_lines[0].pretty_pv.length == 0) {
 560                 $("#history").html("No history");
 561         } else if (truncate_display_history) {
 562                 $("#history").html(print_pv(0, display_lines[0].pretty_pv, 1, 'W', 8, true));
 563         } else {
 564                 $("#history").html(
 565                         '(<a class="move" href="javascript:collapse_history(true)">collapse</a>) ' +
 566                         print_pv(0, display_lines[0].pretty_pv, 1, 'W'));
 567         }
 568 }
 569
 570 /**
 571  * @param {!boolean} truncate_history
 572  */
 573 var collapse_history = function(truncate_history) {
 574         truncate_display_history = truncate_history;
 575         update_history();
 576 }
 577 window['collapse_history'] = collapse_history;
 578
 579 var update_refutation_lines = function() {
 580         if (fen === null) {
 581                 return;
 582         }
 583         if (display_lines.length > 2) {
 584                 display_lines = [ display_lines[0], display_lines[1] ];
 585         }
 586
 587         var tbl = $("#refutationlines");
 588         tbl.empty();
 589
 590         var moves = [];
 591         for (var move in refutation_lines) {
 592                 moves.push(move);
 593         }
 594         var compare = sort_refutation_lines_by_score ? compare_by_score : compare_by_sort_key;
 595         moves = moves.sort(function(a, b) { return compare(refutation_lines, a, b) });
 596         for (var i = 0; i < moves.length; ++i) {
 597                 var line = refutation_lines[moves[i]];
 598
 599                 var tr = document.createElement("tr");
 600
 601                 var move_td = document.createElement("td");
 602                 tr.appendChild(move_td);
 603                 $(move_td).addClass("move");
 604                 if (line['pv_pretty'].length == 0) {
 605                         $(move_td).text(line['pretty_move']);
 606                 } else {
 607                         var move = "<a class=\"move\" href=\"javascript:show_line(" + display_lines.length + ", " + 0 + ");\">" + line['pretty_move'] + "</a>";
 608                         $(move_td).html(move);
 609                 }
 610
 611                 var score_td = document.createElement("td");
 612                 tr.appendChild(score_td);
 613                 $(score_td).addClass("score");
 614                 $(score_td).text(line['pretty_score']);
 615
 616                 var depth_td = document.createElement("td");
 617                 tr.appendChild(depth_td);
 618                 $(depth_td).addClass("depth");
 619                 $(depth_td).text("d" + line['depth']);
 620
 621                 var pv_td = document.createElement("td");
 622                 tr.appendChild(pv_td);
 623                 $(pv_td).addClass("pv");
 624                 $(pv_td).html(add_pv(fen, line['pv_pretty'], move_num, toplay, 10));
 625
 626                 tbl.append(tr);
 627         }
 628
 629         // Make one of the links clickable and the other nonclickable.
 630         if (sort_refutation_lines_by_score) {
 631                 $("#sortbyscore0").html("<a href=\"javascript:resort_refutation_lines(false)\">Move</a>");
 632                 $("#sortbyscore1").html("<strong>Score</strong>");
 633         } else {
 634                 $("#sortbyscore0").html("<strong>Move</strong>");
 635                 $("#sortbyscore1").html("<a href=\"javascript:resort_refutation_lines(true)\">Score</a>");
 636         }
 637 }
 638
 639 /**
 640  * @param {?string} fen
 641  * @param {Array.<string>} moves
 642  * @param {number} last_move
 643  */
 644 var chess_from = function(fen, moves, last_move) {
 645         var hiddenboard = new Chess();
 646         if (fen !== null) {
 647                 hiddenboard.load(fen);
 648         }
 649         for (var i = 0; i <= last_move; ++i) {
 650                 if (moves[i] === '0-0') {
 651                         hiddenboard.move('O-O');
 652                 } else if (moves[i] === '0-0-0') {
 653                         hiddenboard.move('O-O-O');
 654                 } else {
 655                         hiddenboard.move(moves[i]);
 656                 }
 657         }
 658         return hiddenboard;
 659 }
 660
 661 /**
 662  * @param {Object} data
 663  * @param {?Object} display_data
 664  */
 665 var update_board = function(current_data, display_data) {
 666         var data = display_data || current_data;
 667
 668         display_lines = [];
 669
 670         // Print the history. This is pretty much the only thing that's
 671         // unconditionally taken from current_data (we're not interested in
 672         // historic history).
 673         if (current_data['position']['pretty_history']) {
 674                 add_pv('start', current_data['position']['pretty_history'], 1, 'W', 8, true);
 675         } else {
 676                 display_lines.push(null);
 677         }
 678         update_history();
 679
 680         // The headline. Names are always fetched from current_data;
 681         // the rest can depend a bit.
 682         var headline;
 683         if (current_data &&
 684             current_data['position']['player_w'] && current_data['position']['player_b']) {
 685                 headline = current_data['position']['player_w'] + '–' +
 686                         current_data['position']['player_b'] + ', analysis';
 687         } else {
 688                 headline = 'Analysis';
 689         }
 690
 691         var last_move;
 692         if (display_data) {
 693                 // Displaying some non-current position, pick out the last move
 694                 // from the history. This will work even if the fetch failed.
 695                 last_move = format_halfmove_with_number(
 696                         current_display_line.pretty_pv[current_display_move],
 697                         current_display_move + 1);
 698                 headline += ' after ' + last_move;
 699         } else if (data['position']['last_move'] !== 'none') {
 700                 last_move = format_move_with_number(
 701                         data['position']['last_move'],
 702                         data['position']['move_num'],
 703                         data['position']['toplay'] == 'W');
 704                 headline += ' after ' + last_move;
 705         } else {
 706                 last_move = null;
 707         }
 708         $("#headline").text(headline);
 709
 710         // The <title> contains a very brief headline.
 711         var title_elems = [];
 712         if (data['short_score'] !== undefined && data['short_score'] !== null) {
 713                 title_elems.push(data['short_score'].replace(/^ /, ""));
 714         }
 715         if (last_move !== null) {
 716                 title_elems.push(last_move);
 717         }
 718
 719         if (title_elems.length != 0) {
 720                 document.title = '(' + title_elems.join(', ') + ') analysis.sesse.net';
 721         } else {
 722                 document.title = 'analysis.sesse.net';
 723         }
 724
 725         // The last move (shown by highlighting the from and to squares).
 726         if (data['position'] && data['position']['last_move_uci']) {
 727                 highlight_from = data['position']['last_move_uci'].substr(0, 2);
 728                 highlight_to = data['position']['last_move_uci'].substr(2, 2);
 729         } else if (current_display_line_is_history && current_display_move >= 0) {
 730                 // We don't have historic analysis for this position, but we
 731                 // can reconstruct what the last move was by just replaying
 732                 // from the start.
 733                 var hiddenboard = chess_from(null, current_display_line.pretty_pv, current_display_move);
 734                 var moves = hiddenboard.history({ verbose: true });
 735                 var last_move = moves.pop();
 736                 highlight_from = last_move.from;
 737                 highlight_to = last_move.to;
 738         } else {
 739                 highlight_from = highlight_to = undefined;
 740         }
 741         update_highlight();
 742
 743         if (data['failed']) {
 744                 $("#score").text("No analysis for this move");
 745                 $("#pv").empty();
 746                 $("#searchstats").html("&nbsp;");
 747                 $("#refutationlines").empty();
 748                 $("#whiteclock").empty();
 749                 $("#blackclock").empty();
 750                 refutation_lines = [];
 751                 update_refutation_lines();
 752                 clear_arrows();
 753                 update_displayed_line();
 754                 return;
 755         }
 756
 757         update_clock();
 758
 759         // The engine id.
 760         if (data['id'] && data['id']['name'] !== null) {
 761                 $("#engineid").text(data['id']['name']);
 762         }
 763
 764         // The score.
 765         if (data['score'] !== null) {
 766                 $("#score").text(data['score']);
 767         }
 768
 769         // The search stats.
 770         if (data['tablebase'] == 1) {
 771                 $("#searchstats").text("Tablebase result");
 772         } else if (data['nodes'] && data['nps'] && data['depth']) {
 773                 var stats = thousands(data['nodes']) + ' nodes, ' + thousands(data['nps']) + ' nodes/sec, depth ' + data['depth'] + ' ply';
 774                 if (data['seldepth']) {
 775                         stats += ' (' + data['seldepth'] + ' selective)';
 776                 }
 777                 if (data['tbhits'] && data['tbhits'] > 0) {
 778                         if (data['tbhits'] == 1) {
 779                                 stats += ', one Syzygy hit';
 780                         } else {
 781                                 stats += ', ' + thousands(data['tbhits']) + ' Syzygy hits';
 782                         }
 783                 }
 784
 785                 $("#searchstats").text(stats);
 786         } else {
 787                 $("#searchstats").text("");
 788         }
 789
 790         // Update the board itself.
 791         fen = data['position']['fen'];
 792         update_displayed_line();
 793
 794         // Print the PV.
 795         $("#pv").html(add_pv(data['position']['fen'], data['pv_pretty'], data['position']['move_num'], data['position']['toplay']));
 796
 797         // Update the PV arrow.
 798         clear_arrows();
 799         if (data['pv_uci'].length >= 1) {
 800                 // draw a continuation arrow as long as it's the same piece
 801                 for (var i = 0; i < data['pv_uci'].length; i += 2) {
 802                         var from = data['pv_uci'][i].substr(0, 2);
 803                         var to = data['pv_uci'][i].substr(2,4);
 804                         if ((i >= 2 && from != data['pv_uci'][i - 2].substr(2, 2)) ||
 805                              interfering_arrow(from, to)) {
 806                                 break;
 807                         }
 808                         create_arrow(from, to, '#f66', 6, 20);
 809                 }
 810
 811                 var alt_moves = find_nonstupid_moves(data, 30);
 812                 for (var i = 1; i < alt_moves.length && i < 3; ++i) {
 813                         create_arrow(alt_moves[i].substr(0, 2),
 814                                      alt_moves[i].substr(2, 2), '#f66', 1, 10);
 815                 }
 816         }
 817
 818         // See if all semi-reasonable moves have only one possible response.
 819         if (data['pv_uci'].length >= 2) {
 820                 var nonstupid_moves = find_nonstupid_moves(data, 300);
 821                 var response = data['pv_uci'][1];
 822                 for (var i = 0; i < nonstupid_moves.length; ++i) {
 823                         if (nonstupid_moves[i] == data['pv_uci'][0]) {
 824                                 // ignore the PV move for refutation lines.
 825                                 continue;
 826                         }
 827                         if (!data['refutation_lines'] ||
 828                             !data['refutation_lines'][nonstupid_moves[i]] ||
 829                             !data['refutation_lines'][nonstupid_moves[i]]['pv_uci'] ||
 830                             data['refutation_lines'][nonstupid_moves[i]]['pv_uci'].length < 1) {
 831                                 // Incomplete PV, abort.
 832                                 response = undefined;
 833                                 break;
 834                         }
 835                         var this_response = data['refutation_lines'][nonstupid_moves[i]]['pv_uci'][1];
 836                         if (response !== this_response) {
 837                                 // Different response depending on lines, abort.
 838                                 response = undefined;
 839                                 break;
 840                         }
 841                 }
 842
 843                 if (nonstupid_moves.length > 0 && response !== undefined) {
 844                         create_arrow(response.substr(0, 2),
 845                                      response.substr(2, 2), '#66f', 6, 20);
 846                 }
 847         }
 848
 849         // Update the refutation lines.
 850         fen = data['position']['fen'];
 851         move_num = data['position']['move_num'];
 852         toplay = data['position']['toplay'];
 853         refutation_lines = data['refutation_lines'];
 854         update_refutation_lines();
 855
 856         // Update the sparkline last, since its size depends on how everything else reflowed.
 857         update_sparkline(data);
 858 }
 859
 860 var update_sparkline = function(data) {
 861         if (data && data['score_history']) {
 862                 var first_move_num = undefined;
 863                 for (var halfmove_num in data['score_history']) {
 864                         halfmove_num = parseInt(halfmove_num);
 865                         if (first_move_num === undefined || halfmove_num < first_move_num) {
 866                                 first_move_num = halfmove_num;
 867                         }
 868                 }
 869                 if (first_move_num !== undefined) {
 870                         var last_move_num = data['position']['move_num'] * 2 - 3;
 871                         if (data['position']['toplay'] === 'B') {
 872                                 ++last_move_num;
 873                         }
 874
 875                         // Possibly truncate some moves if we don't have enough width.
 876                         // FIXME: Sometimes width() for #scorecontainer (and by extent,
 877                         // #scoresparkcontainer) on Chrome for mobile seems to start off
 878                         // at something very small, and then suddenly snap back into place.
 879                         // Figure out why.
 880                         var max_moves = Math.floor($("#scoresparkcontainer").width() / 5) - 5;
 881                         if (last_move_num - first_move_num > max_moves) {
 882                                 first_move_num = last_move_num - max_moves;
 883                         }
 884
 885                         var min_score = -100;
 886                         var max_score = 100;
 887                         var last_score = null;
 888                         var scores = [];
 889                         for (var halfmove_num = first_move_num; halfmove_num <= last_move_num; ++halfmove_num) {
 890                                 if (data['score_history'][halfmove_num]) {
 891                                         var score = data['score_history'][halfmove_num][0];
 892                                         if (score < min_score) min_score = score;
 893                                         if (score > max_score) max_score = score;
 894                                         last_score = data['score_history'][halfmove_num][0];
 895                                 }
 896                                 scores.push(last_score);
 897                         }
 898                         if (data['plot_score']) {
 899                                 scores.push(data['plot_score']);
 900                         }
 901                         // FIXME: at some widths, calling sparkline() seems to push
 902                         // #scorecontainer under the board.
 903                         $("#scorespark").sparkline(scores, {
 904                                 type: 'bar',
 905                                 zeroColor: 'gray',
 906                                 chartRangeMin: min_score,
 907                                 chartRangeMax: max_score,
 908                                 tooltipFormatter: function(sparkline, options, fields) {
 909                                         return format_tooltip(data, fields[0].offset + first_move_num);
 910                                 }
 911                         });
 912                 } else {
 913                         $("#scorespark").text("");
 914                 }
 915         } else {
 916                 $("#scorespark").text("");
 917         }
 918 }
 919
 920 /**
 921  * @param {number} num_viewers
 922  */
 923 var update_num_viewers = function(num_viewers) {
 924         if (num_viewers === null) {
 925                 $("#numviewers").text("");
 926         } else if (num_viewers == 1) {
 927                 $("#numviewers").text("You are the only current viewer");
 928         } else {
 929                 $("#numviewers").text(num_viewers + " current viewers");
 930         }
 931 }
 932
 933 var update_clock = function() {
 934         clearTimeout(clock_timer);
 935
 936         var data = displayed_analysis_data || current_analysis_data;
 937         if (data['position']) {
 938                 var result = data['position']['result'];
 939                 if (result === '1-0') {
 940                         $("#whiteclock").text("1");
 941                         $("#blackclock").text("0");
 942                         $("#whiteclock").removeClass("running-clock");
 943                         $("#blackclock").removeClass("running-clock");
 944                         return;
 945                 }
 946                 if (result === '1/2-1/2') {
 947                         $("#whiteclock").text("1/2");
 948                         $("#blackclock").text("1/2");
 949                         $("#whiteclock").removeClass("running-clock");
 950                         $("#blackclock").removeClass("running-clock");
 951                         return;
 952                 }
 953                 if (result === '0-1') {
 954                         $("#whiteclock").text("0");
 955                         $("#blackclock").text("1");
 956                         $("#whiteclock").removeClass("running-clock");
 957                         $("#blackclock").removeClass("running-clock");
 958                         return;
 959                 }
 960         }
 961
 962         var white_clock_ms = null;
 963         var black_clock_ms = null;
 964         var show_seconds = false;
 965
 966         // Static clocks.
 967         if (data['position'] &&
 968             data['position']['white_clock'] &&
 969             data['position']['black_clock']) {
 970                 white_clock_ms = data['position']['white_clock'] * 1000;
 971                 black_clock_ms = data['position']['black_clock'] * 1000;
 972         }
 973
 974         // Dynamic clock (only one, obviously).
 975         var color;
 976         if (data['position']['white_clock_target']) {
 977                 color = "white";
 978                 $("#whiteclock").addClass("running-clock");
 979                 $("#blackclock").removeClass("running-clock");
 980         } else if (data['position']['black_clock_target']) {
 981                 color = "black";
 982                 $("#whiteclock").removeClass("running-clock");
 983                 $("#blackclock").addClass("running-clock");
 984         } else {
 985                 $("#whiteclock").removeClass("running-clock");
 986                 $("#blackclock").removeClass("running-clock");
 987         }
 988         var remaining_ms;
 989         if (color) {
 990                 var now = new Date().getTime() + client_clock_offset_ms;
 991                 remaining_ms = data['position'][color + '_clock_target'] * 1000 - now;
 992                 if (color === "white") {
 993                         white_clock_ms = remaining_ms;
 994                 } else {
 995                         black_clock_ms = remaining_ms;
 996                 }
 997         }
 998
 999         if (white_clock_ms === null || black_clock_ms === null) {
1000                 $("#whiteclock").empty();
1001                 $("#blackclock").empty();
1002                 return;
1003         }
1004
1005         // If either player has ten minutes or less left, add the second counters.
1006         var show_seconds = (white_clock_ms < 60 * 10 * 1000 || black_clock_ms < 60 * 10 * 1000);
1007
1008         if (color) {
1009                 // See when the clock will change next, and update right after that.
1010                 var next_update_ms;
1011                 if (show_seconds) {
1012                         next_update_ms = remaining_ms % 1000 + 100;
1013                 } else {
1014                         next_update_ms = remaining_ms % 60000 + 100;
1015                 }
1016                 clock_timer = setTimeout(update_clock, next_update_ms);
1017         }
1018
1019         $("#whiteclock").text(format_clock(white_clock_ms, show_seconds));
1020         $("#blackclock").text(format_clock(black_clock_ms, show_seconds));
1021 }
1022
1023 /**
1024  * @param {Number} remaining_ms
1025  * @param {boolean} show_seconds
1026  */
1027 var format_clock = function(remaining_ms, show_seconds) {
1028         if (remaining_ms <= 0) {
1029                 if (show_seconds) {
1030                         return "00:00:00";
1031                 } else {
1032                         return "00:00";
1033                 }
1034         }
1035
1036         var remaining = Math.floor(remaining_ms / 1000);
1037         var seconds = remaining % 60;
1038         remaining = (remaining - seconds) / 60;
1039         var minutes = remaining % 60;
1040         remaining = (remaining - minutes) / 60;
1041         var hours = remaining;
1042         if (show_seconds) {
1043                 return format_2d(hours) + ":" + format_2d(minutes) + ":" + format_2d(seconds);
1044         } else {
1045                 return format_2d(hours) + ":" + format_2d(minutes);
1046         }
1047 }
1048
1049 /**
1050  * @param {Number} x
1051  */
1052 var format_2d = function(x) {
1053         if (x >= 10) {
1054                 return x;
1055         } else {
1056                 return "0" + x;
1057         }
1058 }
1059
1060 /**
1061  * @param {string} move
1062  * @param {Number} move_num
1063  * @param {boolean} white_to_play
1064  */
1065 var format_move_with_number = function(move, move_num, white_to_play) {
1066         var ret;
1067         if (white_to_play) {
1068                 ret = (move_num - 1) + '… ';
1069         } else {
1070                 ret = move_num + '. ';
1071         }
1072         ret += move;
1073         return ret;
1074 }
1075
1076 /**
1077  * @param {string} move
1078  * @param {Number} halfmove_num
1079  */
1080 var format_halfmove_with_number = function(move, halfmove_num) {
1081         return format_move_with_number(
1082                 move,
1083                 Math.floor(halfmove_num / 2) + 1,
1084                 halfmove_num % 2 == 0);
1085 }
1086
1087 /**
1088  * @param {Object} data
1089  * @param {Number} halfmove_num
1090  */
1091 var format_tooltip = function(data, halfmove_num) {
1092         if (data['score_history'][halfmove_num] ||
1093             halfmove_num === data['position']['pretty_history'].length) {
1094                 var move;
1095                 var short_score;
1096                 if (halfmove_num === data['position']['pretty_history'].length) {
1097                         move = data['position']['last_move'];
1098                         short_score = data['short_score'];
1099                 } else {
1100                         move = data['position']['pretty_history'][halfmove_num];
1101                         short_score = data['score_history'][halfmove_num][1];
1102                 }
1103                 var move_with_number = format_halfmove_with_number(move, halfmove_num);
1104
1105                 return "After " + move_with_number + ": " + short_score;
1106         } else {
1107                 for (var i = halfmove_num; i --> 0; ) {
1108                         if (data['score_history'][i]) {
1109                                 var move = data['position']['pretty_history'][i];
1110                                 return "[Analysis kept from " + format_halfmove_with_number(move, i) + "]";
1111                         }
1112                 }
1113         }
1114 }
1115
1116 /**
1117  * @param {boolean} sort_by_score
1118  */
1119 var resort_refutation_lines = function(sort_by_score) {
1120         sort_refutation_lines_by_score = sort_by_score;
1121         if (supports_html5_storage()) {
1122                 localStorage['sort_refutation_lines_by_score'] = sort_by_score ? 1 : 0;
1123         }
1124         update_refutation_lines();
1125 }
1126 window['resort_refutation_lines'] = resort_refutation_lines;
1127
1128 /**
1129  * @param {boolean} truncate_history
1130  */
1131 var set_truncate_history = function(truncate_history) {
1132         truncate_display_history = truncate_history;
1133         update_refutation_lines();
1134 }
1135 window['set_truncate_history'] = set_truncate_history;
1136
1137 /**
1138  * @param {number} line_num
1139  * @param {number} move_num
1140  */
1141 var show_line = function(line_num, move_num) {
1142         if (line_num == -1) {
1143                 current_display_line = null;
1144                 current_display_move = null;
1145                 if (displayed_analysis_data) {
1146                         // TODO: Support exiting to history position if we are in an
1147                         // analysis line of a history position.
1148                         displayed_analysis_data = null;
1149                         update_board(current_analysis_data, displayed_analysis_data);
1150                 }
1151         } else {
1152                 current_display_line = display_lines[line_num];
1153                 current_display_move = move_num;
1154         }
1155         current_display_line_is_history = (line_num == 0);
1156
1157         update_historic_analysis();
1158         update_displayed_line();
1159         update_highlight();
1160         redraw_arrows();
1161 }
1162 window['show_line'] = show_line;
1163
1164 var prev_move = function() {
1165         if (current_display_move > -1) {
1166                 --current_display_move;
1167         }
1168         update_historic_analysis();
1169         update_displayed_line();
1170 }
1171 window['prev_move'] = prev_move;
1172
1173 var next_move = function() {
1174         if (current_display_line && current_display_move < current_display_line.pretty_pv.length - 1) {
1175                 ++current_display_move;
1176         }
1177         update_historic_analysis();
1178         update_displayed_line();
1179 }
1180 window['next_move'] = next_move;
1181
1182 var update_historic_analysis = function() {
1183         if (!current_display_line_is_history) {
1184                 return;
1185         }
1186         if (current_display_move == current_display_line.pretty_pv.length - 1) {
1187                 displayed_analysis_data = null;
1188                 update_board(current_analysis_data, displayed_analysis_data);
1189         }
1190
1191         // Fetch old analysis for this line if it exists.
1192         var hiddenboard = chess_from(null, current_display_line.pretty_pv, current_display_move);
1193         var filename = "/history/move" + (current_display_move + 1) + "-" +
1194                 hiddenboard.fen().replace(/ /g, '_').replace(/\//g, '-') + ".json";
1195
1196         $.ajax({
1197                 url: filename
1198         }).done(function(data, textstatus, xhr) {
1199                 displayed_analysis_data = data;
1200                 update_board(current_analysis_data, displayed_analysis_data);
1201         }).fail(function() {
1202                 displayed_analysis_data = {'failed': true};
1203                 update_board(current_analysis_data, displayed_analysis_data);
1204         });
1205 }
1206
1207 /**
1208  * @param {string} fen
1209  */
1210 var update_imbalance = function(fen) {
1211         var hiddenboard = new Chess(fen);
1212         var imbalance = {'k': 0, 'q': 0, 'r': 0, 'b': 0, 'n': 0, 'p': 0};
1213         for (var row = 0; row < 8; ++row) {
1214                 for (var col = 0; col < 8; ++col) {
1215                         var col_text = String.fromCharCode('a1'.charCodeAt(0) + col);
1216                         var row_text = String.fromCharCode('a1'.charCodeAt(1) + row);
1217                         var square = col_text + row_text;
1218                         var contents = hiddenboard.get(square);
1219                         if (contents !== null) {
1220                                 if (contents.color === 'w') {
1221                                         ++imbalance[contents.type];
1222                                 } else {
1223                                         --imbalance[contents.type];
1224                                 }
1225                         }
1226                 }
1227         }
1228         var white_imbalance = '';
1229         var black_imbalance = '';
1230         for (var piece in imbalance) {
1231                 for (var i = 0; i < imbalance[piece]; ++i) {
1232                         white_imbalance += '<img src="img/chesspieces/wikipedia/w' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1233                 }
1234                 for (var i = 0; i < -imbalance[piece]; ++i) {
1235                         black_imbalance += '<img src="img/chesspieces/wikipedia/b' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1236                 }
1237         }
1238         $('#whiteimbalance').html(white_imbalance);
1239         $('#blackimbalance').html(black_imbalance);
1240 }
1241
1242 var update_displayed_line = function() {
1243         if (highlighted_move !== null) {
1244                 highlighted_move.removeClass('highlight');
1245         }
1246         if (current_display_line === null) {
1247                 $("#linenav").hide();
1248                 $("#linemsg").show();
1249                 board.position(fen);
1250                 update_imbalance(fen);
1251                 return;
1252         }
1253
1254         $("#linenav").show();
1255         $("#linemsg").hide();
1256
1257         if (current_display_move <= 0) {
1258                 $("#prevmove").html("Previous");
1259         } else {
1260                 $("#prevmove").html("<a href=\"javascript:prev_move();\">Previous</a></span>");
1261         }
1262         if (current_display_move == current_display_line.pretty_pv.length - 1) {
1263                 $("#nextmove").html("Next");
1264         } else {
1265                 $("#nextmove").html("<a href=\"javascript:next_move();\">Next</a></span>");
1266         }
1267
1268         highlighted_move = $("#automove" + current_display_line.line_number + "-" + current_display_move);
1269         highlighted_move.addClass('highlight');
1270
1271         var hiddenboard = chess_from(current_display_line.start_fen, current_display_line.pretty_pv, current_display_move);
1272         board.position(hiddenboard.fen());
1273         update_imbalance(hiddenboard.fen());
1274 }
1275
1276 /**
1277  * @param {boolean} param_enable_sound
1278  */
1279 var set_sound = function(param_enable_sound) {
1280         enable_sound = param_enable_sound;
1281         if (enable_sound) {
1282                 $("#soundon").html("<strong>On</strong>");
1283                 $("#soundoff").html("<a href=\"javascript:set_sound(false)\">Off</a>");
1284
1285                 // Seemingly at least Firefox prefers MP3 over Opus; tell it otherwise,
1286                 // and also preload the file since the user has selected audio.
1287                 var ding = document.getElementById('ding');
1288                 if (ding && ding.canPlayType && ding.canPlayType('audio/ogg; codecs="opus"') === 'probably') {
1289                         ding.src = 'ding.opus';
1290                         ding.load();
1291                 }
1292         } else {
1293                 $("#soundon").html("<a href=\"javascript:set_sound(true)\">On</a>");
1294                 $("#soundoff").html("<strong>Off</strong>");
1295         }
1296         if (supports_html5_storage()) {
1297                 localStorage['enable_sound'] = enable_sound ? 1 : 0;
1298         }
1299 }
1300 window['set_sound'] = set_sound;
1301
1302 var init = function() {
1303         unique = get_unique();
1304
1305         // Load settings from HTML5 local storage if available.
1306         if (supports_html5_storage() && localStorage['enable_sound']) {
1307                 set_sound(parseInt(localStorage['enable_sound']));
1308         } else {
1309                 set_sound(false);
1310         }
1311         if (supports_html5_storage() && localStorage['sort_refutation_lines_by_score']) {
1312                 sort_refutation_lines_by_score = parseInt(localStorage['sort_refutation_lines_by_score']);
1313         } else {
1314                 sort_refutation_lines_by_score = true;
1315         }
1316
1317         // Create board.
1318         board = new window.ChessBoard('board', 'start');
1319
1320         request_update();
1321         $(window).resize(function() {
1322                 board.resize();
1323                 update_sparkline(displayed_analysis_data || current_analysis_data);
1324                 update_highlight();
1325                 redraw_arrows();
1326         });
1327         $(window).keyup(function(event) {
1328                 if (event.which == 39) {
1329                         next_move();
1330                 } else if (event.which == 37) {
1331                         prev_move();
1332                 }
1333         });
1334 };
1335 $(document).ready(init);
1336
1337 })();