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_delta.patch(current_analysis_data, data);
 143                 } else {
 144                         new_data = data;
 145                 }
 146                 possibly_play_sound(current_analysis_data, new_data);
 147                 current_analysis_data = new_data;
 148                 update_board(current_analysis_data, displayed_analysis_data);
 149                 update_num_viewers(num_viewers);
 150
 151                 // Next update.
 152                 setTimeout(function() { request_update(); }, 100);
 153         }).fail(function() {
 154                 // Wait ten seconds, then try again.
 155                 setTimeout(function() { request_update(); }, 10000);
 156         });
 157 }
 158
 159 var possibly_play_sound = function(old_data, new_data) {
 160         if (!enable_sound) {
 161                 return;
 162         }
 163         if (old_data === null) {
 164                 return;
 165         }
 166         var ding = document.getElementById('ding');
 167         if (ding && ding.play) {
 168                 if (old_data['position'] && old_data['position']['fen'] &&
 169                     new_data['position'] && new_data['position']['fen'] &&
 170                     (old_data['position']['fen'] !== new_data['position']['fen'] ||
 171                      old_data['position']['move_num'] !== new_data['position']['move_num'])) {
 172                         ding.play();
 173                 }
 174         }
 175 }
 176
 177 /**
 178  * @type {!string} server_date_string
 179  */
 180 var sync_server_clock = function(server_date_string) {
 181         var server_time_ms = new Date(server_date_string).getTime();
 182         var client_time_ms = new Date().getTime();
 183         var estimated_offset_ms = server_time_ms - client_time_ms;
 184
 185         // In order not to let the noise move us too much back and forth
 186         // (the server only has one-second resolution anyway), we only
 187         // change an existing skew if we are at least five seconds off.
 188         if (client_clock_offset_ms === null ||
 189             Math.abs(estimated_offset_ms - client_clock_offset_ms) > 5000) {
 190                 client_clock_offset_ms = estimated_offset_ms;
 191         }
 192 }
 193
 194 var clear_arrows = function() {
 195         for (var i = 0; i < arrows.length; ++i) {
 196                 if (arrows[i].svg) {
 197                         arrows[i].svg.parentElement.removeChild(arrows[i].svg);
 198                         delete arrows[i].svg;
 199                 }
 200         }
 201         arrows = [];
 202
 203         occupied_by_arrows = [];
 204         for (var y = 0; y < 8; ++y) {
 205                 occupied_by_arrows.push([false, false, false, false, false, false, false, false]);
 206         }
 207 }
 208
 209 var redraw_arrows = function() {
 210         for (var i = 0; i < arrows.length; ++i) {
 211                 position_arrow(arrows[i]);
 212         }
 213 }
 214
 215 /** @param {!number} x
 216  * @return {!number}
 217  */
 218 var sign = function(x) {
 219         if (x > 0) {
 220                 return 1;
 221         } else if (x < 0) {
 222                 return -1;
 223         } else {
 224                 return 0;
 225         }
 226 }
 227
 228 /** See if drawing this arrow on the board would cause unduly amount of confusion.
 229  * @param {!string} from The square the arrow is from (e.g. e4).
 230  * @param {!string} to The square the arrow is to (e.g. e4).
 231  * @return {boolean}
 232  */
 233 var interfering_arrow = function(from, to) {
 234         var from_col = from.charCodeAt(0) - "a1".charCodeAt(0);
 235         var from_row = from.charCodeAt(1) - "a1".charCodeAt(1);
 236         var to_col   = to.charCodeAt(0) - "a1".charCodeAt(0);
 237         var to_row   = to.charCodeAt(1) - "a1".charCodeAt(1);
 238
 239         occupied_by_arrows[from_row][from_col] = true;
 240
 241         // Knight move: Just check that we haven't been at the destination before.
 242         if ((Math.abs(to_col - from_col) == 2 && Math.abs(to_row - from_row) == 1) ||
 243             (Math.abs(to_col - from_col) == 1 && Math.abs(to_row - from_row) == 2)) {
 244                 return occupied_by_arrows[to_row][to_col];
 245         }
 246
 247         // Sliding piece: Check if anything except the from-square is seen before.
 248         var dx = sign(to_col - from_col);
 249         var dy = sign(to_row - from_row);
 250         var x = from_col;
 251         var y = from_row;
 252         do {
 253                 x += dx;
 254                 y += dy;
 255                 if (occupied_by_arrows[y][x]) {
 256                         return true;
 257                 }
 258                 occupied_by_arrows[y][x] = true;
 259         } while (x != to_col || y != to_row);
 260
 261         return false;
 262 }
 263
 264 /** Find a point along the coordinate system given by the given line,
 265  * <t> units forward from the start of the line, <u> units to the right of it.
 266  * @param {!number} x1
 267  * @param {!number} x2
 268  * @param {!number} y1
 269  * @param {!number} y2
 270  * @param {!number} t
 271  * @param {!number} u
 272  * @return {!string} The point in "x y" form, suitable for SVG paths.
 273  */
 274 var point_from_start = function(x1, y1, x2, y2, t, u) {
 275         var dx = x2 - x1;
 276         var dy = y2 - y1;
 277
 278         var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
 279         dx *= norm;
 280         dy *= norm;
 281
 282         var x = x1 + dx * t + dy * u;
 283         var y = y1 + dy * t - dx * u;
 284         return x + " " + y;
 285 }
 286
 287 /** Find a point along the coordinate system given by the given line,
 288  * <t> units forward from the end of the line, <u> units to the right of it.
 289  * @param {!number} x1
 290  * @param {!number} x2
 291  * @param {!number} y1
 292  * @param {!number} y2
 293  * @param {!number} t
 294  * @param {!number} u
 295  * @return {!string} The point in "x y" form, suitable for SVG paths.
 296  */
 297 var point_from_end = function(x1, y1, x2, y2, t, u) {
 298         var dx = x2 - x1;
 299         var dy = y2 - y1;
 300
 301         var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
 302         dx *= norm;
 303         dy *= norm;
 304
 305         var x = x2 + dx * t + dy * u;
 306         var y = y2 + dy * t - dx * u;
 307         return x + " " + y;
 308 }
 309
 310 var position_arrow = function(arrow) {
 311         if (arrow.svg) {
 312                 arrow.svg.parentElement.removeChild(arrow.svg);
 313                 delete arrow.svg;
 314         }
 315         if (current_display_line !== null && !current_display_line_is_history) {
 316                 return;
 317         }
 318
 319         var pos = $(".square-a8").position();
 320
 321         var zoom_factor = $("#board").width() / 400.0;
 322         var line_width = arrow.line_width * zoom_factor;
 323         var arrow_size = arrow.arrow_size * zoom_factor;
 324
 325         var square_width = $(".square-a8").width();
 326         var from_y = (7 - arrow.from_row + 0.5)*square_width;
 327         var to_y = (7 - arrow.to_row + 0.5)*square_width;
 328         var from_x = (arrow.from_col + 0.5)*square_width;
 329         var to_x = (arrow.to_col + 0.5)*square_width;
 330
 331         var SVG_NS = "http://www.w3.org/2000/svg";
 332         var XHTML_NS = "http://www.w3.org/1999/xhtml";
 333         var svg = document.createElementNS(SVG_NS, "svg");
 334         svg.setAttribute("width", /** @type{number} */ ($("#board").width()));
 335         svg.setAttribute("height", /** @type{number} */ ($("#board").height()));
 336         svg.setAttribute("style", "position: absolute");
 337         svg.setAttribute("position", "absolute");
 338         svg.setAttribute("version", "1.1");
 339         svg.setAttribute("class", "c1");
 340         svg.setAttribute("xmlns", XHTML_NS);
 341
 342         var x1 = from_x;
 343         var y1 = from_y;
 344         var x2 = to_x;
 345         var y2 = to_y;
 346
 347         // Draw the line.
 348         var outline = document.createElementNS(SVG_NS, "path");
 349         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));
 350         outline.setAttribute("xmlns", XHTML_NS);
 351         outline.setAttribute("stroke", "#666");
 352         outline.setAttribute("stroke-width", line_width + 2);
 353         outline.setAttribute("fill", "none");
 354         svg.appendChild(outline);
 355
 356         var path = document.createElementNS(SVG_NS, "path");
 357         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));
 358         path.setAttribute("xmlns", XHTML_NS);
 359         path.setAttribute("stroke", arrow.fg_color);
 360         path.setAttribute("stroke-width", line_width);
 361         path.setAttribute("fill", "none");
 362         svg.appendChild(path);
 363
 364         // Then the arrow head.
 365         var head = document.createElementNS(SVG_NS, "path");
 366         head.setAttribute("d",
 367                 "M " +  point_from_end(x1, y1, x2, y2, 0, 0) +
 368                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, -arrow_size / 2) +
 369                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size * .623, 0.0) +
 370                 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, arrow_size / 2) +
 371                 " L " + point_from_end(x1, y1, x2, y2, 0, 0));
 372         head.setAttribute("xmlns", XHTML_NS);
 373         head.setAttribute("stroke", "#000");
 374         head.setAttribute("stroke-width", "1");
 375         head.setAttribute("fill", arrow.fg_color);
 376         svg.appendChild(head);
 377
 378         $(svg).css({ top: pos.top, left: pos.left });
 379         document.body.appendChild(svg);
 380         arrow.svg = svg;
 381 }
 382
 383 /**
 384  * @param {!string} from_square
 385  * @param {!string} to_square
 386  * @param {!string} fg_color
 387  * @param {number} line_width
 388  * @param {number} arrow_size
 389  */
 390 var create_arrow = function(from_square, to_square, fg_color, line_width, arrow_size) {
 391         var from_col = from_square.charCodeAt(0) - "a1".charCodeAt(0);
 392         var from_row = from_square.charCodeAt(1) - "a1".charCodeAt(1);
 393         var to_col   = to_square.charCodeAt(0) - "a1".charCodeAt(0);
 394         var to_row   = to_square.charCodeAt(1) - "a1".charCodeAt(1);
 395
 396         // Create arrow.
 397         var arrow = {
 398                 from_col: from_col,
 399                 from_row: from_row,
 400                 to_col: to_col,
 401                 to_row: to_row,
 402                 line_width: line_width,
 403                 arrow_size: arrow_size,
 404                 fg_color: fg_color
 405         };
 406
 407         position_arrow(arrow);
 408         arrows.push(arrow);
 409 }
 410
 411 var compare_by_sort_key = function(refutation_lines, a, b) {
 412         var ska = refutation_lines[a]['sort_key'];
 413         var skb = refutation_lines[b]['sort_key'];
 414         if (ska < skb) return -1;
 415         if (ska > skb) return 1;
 416         return 0;
 417 };
 418
 419 var compare_by_score = function(refutation_lines, a, b) {
 420         var sa = parseInt(refutation_lines[b]['score_sort_key'], 10);
 421         var sb = parseInt(refutation_lines[a]['score_sort_key'], 10);
 422         return sa - sb;
 423 }
 424
 425 /**
 426  * Fake multi-PV using the refutation lines. Find all “relevant” moves,
 427  * sorted by quality, descending.
 428  *
 429  * @param {!Object} data
 430  * @param {number} margin The maximum number of centipawns worse than the
 431  *     best move can be and still be included.
 432  * @return {Array.<string>} The UCI representation (e.g. e1g1) of all
 433  *     moves, in score order.
 434  */
 435 var find_nonstupid_moves = function(data, margin) {
 436         // First of all, if there are any moves that are more than 0.5 ahead of
 437         // the primary move, the refutation lines are probably bunk, so just
 438         // kill them all.
 439         var best_score = undefined;
 440         var pv_score = undefined;
 441         for (var move in data['refutation_lines']) {
 442                 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
 443                 if (move == data['pv_uci'][0]) {
 444                         pv_score = score;
 445                 }
 446                 if (best_score === undefined || score > best_score) {
 447                         best_score = score;
 448                 }
 449                 if (!(data['refutation_lines'][move]['depth'] >= 8)) {
 450                         return [];
 451                 }
 452         }
 453
 454         if (best_score - pv_score > 50) {
 455                 return [];
 456         }
 457
 458         // Now find all moves that are within “margin” of the best score.
 459         // The PV move will always be first.
 460         var moves = [];
 461         for (var move in data['refutation_lines']) {
 462                 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
 463                 if (move != data['pv_uci'][0] && best_score - score <= margin) {
 464                         moves.push(move);
 465                 }
 466         }
 467         moves = moves.sort(function(a, b) { return compare_by_score(data['refutation_lines'], a, b) });
 468         moves.unshift(data['pv_uci'][0]);
 469
 470         return moves;
 471 }
 472
 473 /**
 474  * @param {number} x
 475  * @return {!string}
 476  */
 477 var thousands = function(x) {
 478         return String(x).split('').reverse().join('').replace(/(\d{3}\B)/g, '$1,').split('').reverse().join('');
 479 }
 480
 481 /**
 482  * @param {!string} fen
 483  * @param {Array.<string>} pretty_pv
 484  * @param {number} move_num
 485  * @param {!string} toplay
 486  * @param {number=} opt_limit
 487  * @param {boolean=} opt_showlast
 488  */
 489 var add_pv = function(fen, pretty_pv, move_num, toplay, opt_limit, opt_showlast) {
 490         display_lines.push({
 491                 start_fen: fen,
 492                 pretty_pv: pretty_pv,
 493                 line_number: display_lines.length
 494         });
 495         return print_pv(display_lines.length - 1, pretty_pv, move_num, toplay, opt_limit, opt_showlast);
 496 }
 497
 498 /**
 499  * @param {number} line_num
 500  * @param {Array.<string>} pretty_pv
 501  * @param {number} move_num
 502  * @param {!string} toplay
 503  * @param {number=} opt_limit
 504  * @param {boolean=} opt_showlast
 505  */
 506 var print_pv = function(line_num, pretty_pv, move_num, toplay, opt_limit, opt_showlast) {
 507         var pv = '';
 508         var i = 0;
 509         if (opt_limit && opt_showlast && pretty_pv.length > opt_limit) {
 510                 // Truncate the PV at the beginning (instead of at the end).
 511                 // We assume here that toplay is 'W'. We also assume that if
 512                 // opt_showlast is set, then it is the history, and thus,
 513                 // the UI should be to expand the history.
 514                 pv = '(<a class="move" href="javascript:collapse_history(false)">…</a>) ';
 515                 i = pretty_pv.length - opt_limit;
 516                 if (i % 2 == 1) {
 517                         ++i;
 518                 }
 519                 move_num += i / 2;
 520         } else if (toplay == 'B' && pretty_pv.length > 0) {
 521                 var move = "<a class=\"move\" id=\"automove" + line_num + "-0\" href=\"javascript:show_line(" + line_num + ", " + 0 + ");\">" + pretty_pv[0] + "</a>";
 522                 pv = move_num + '. … ' + move;
 523                 toplay = 'W';
 524                 ++i;
 525                 ++move_num;
 526         }
 527         for ( ; i < pretty_pv.length; ++i) {
 528                 var move = "<a class=\"move\" id=\"automove" + line_num + "-" + i + "\" href=\"javascript:show_line(" + line_num + ", " + i + ");\">" + pretty_pv[i] + "</a>";
 529
 530                 if (toplay == 'W') {
 531                         if (i > opt_limit && !opt_showlast) {
 532                                 return pv + ' (…)';
 533                         }
 534                         if (pv != '') {
 535                                 pv += ' ';
 536                         }
 537                         pv += move_num + '. ' + move;
 538                         ++move_num;
 539                         toplay = 'B';
 540                 } else {
 541                         pv += ' ' + move;
 542                         toplay = 'W';
 543                 }
 544         }
 545         return pv;
 546 }
 547
 548 var update_highlight = function() {
 549         $("#board").find('.square-55d63').removeClass('nonuglyhighlight');
 550         if ((current_display_line === null || current_display_line_is_history) &&
 551             highlight_from !== undefined && highlight_to !== undefined) {
 552                 $("#board").find('.square-' + highlight_from).addClass('nonuglyhighlight');
 553                 $("#board").find('.square-' + highlight_to).addClass('nonuglyhighlight');
 554         }
 555 }
 556
 557 var update_history = function() {
 558         if (display_lines[0] === null || display_lines[0].pretty_pv.length == 0) {
 559                 $("#history").html("No history");
 560         } else if (truncate_display_history) {
 561                 $("#history").html(print_pv(0, display_lines[0].pretty_pv, 1, 'W', 8, true));
 562         } else {
 563                 $("#history").html(
 564                         '(<a class="move" href="javascript:collapse_history(true)">collapse</a>) ' +
 565                         print_pv(0, display_lines[0].pretty_pv, 1, 'W'));
 566         }
 567 }
 568
 569 /**
 570  * @param {!boolean} truncate_history
 571  */
 572 var collapse_history = function(truncate_history) {
 573         truncate_display_history = truncate_history;
 574         update_history();
 575 }
 576 window['collapse_history'] = collapse_history;
 577
 578 var update_refutation_lines = function() {
 579         if (fen === null) {
 580                 return;
 581         }
 582         if (display_lines.length > 2) {
 583                 display_lines = [ display_lines[0], display_lines[1] ];
 584         }
 585
 586         var tbl = $("#refutationlines");
 587         tbl.empty();
 588
 589         var moves = [];
 590         for (var move in refutation_lines) {
 591                 moves.push(move);
 592         }
 593         var compare = sort_refutation_lines_by_score ? compare_by_score : compare_by_sort_key;
 594         moves = moves.sort(function(a, b) { return compare(refutation_lines, a, b) });
 595         for (var i = 0; i < moves.length; ++i) {
 596                 var line = refutation_lines[moves[i]];
 597
 598                 var tr = document.createElement("tr");
 599
 600                 var move_td = document.createElement("td");
 601                 tr.appendChild(move_td);
 602                 $(move_td).addClass("move");
 603                 if (line['pv_pretty'].length == 0) {
 604                         $(move_td).text(line['pretty_move']);
 605                 } else {
 606                         var move = "<a class=\"move\" href=\"javascript:show_line(" + display_lines.length + ", " + 0 + ");\">" + line['pretty_move'] + "</a>";
 607                         $(move_td).html(move);
 608                 }
 609
 610                 var score_td = document.createElement("td");
 611                 tr.appendChild(score_td);
 612                 $(score_td).addClass("score");
 613                 $(score_td).text(line['pretty_score']);
 614
 615                 var depth_td = document.createElement("td");
 616                 tr.appendChild(depth_td);
 617                 $(depth_td).addClass("depth");
 618                 $(depth_td).text("d" + line['depth']);
 619
 620                 var pv_td = document.createElement("td");
 621                 tr.appendChild(pv_td);
 622                 $(pv_td).addClass("pv");
 623                 $(pv_td).html(add_pv(fen, line['pv_pretty'], move_num, toplay, 10));
 624
 625                 tbl.append(tr);
 626         }
 627
 628         // Make one of the links clickable and the other nonclickable.
 629         if (sort_refutation_lines_by_score) {
 630                 $("#sortbyscore0").html("<a href=\"javascript:resort_refutation_lines(false)\">Move</a>");
 631                 $("#sortbyscore1").html("<strong>Score</strong>");
 632         } else {
 633                 $("#sortbyscore0").html("<strong>Move</strong>");
 634                 $("#sortbyscore1").html("<a href=\"javascript:resort_refutation_lines(true)\">Score</a>");
 635         }
 636 }
 637
 638 /**
 639  * @param {?string} fen
 640  * @param {Array.<string>} moves
 641  * @param {number} last_move
 642  */
 643 var chess_from = function(fen, moves, last_move) {
 644         var hiddenboard = new Chess();
 645         if (fen !== null) {
 646                 hiddenboard.load(fen);
 647         }
 648         for (var i = 0; i <= last_move; ++i) {
 649                 if (moves[i] === '0-0') {
 650                         hiddenboard.move('O-O');
 651                 } else if (moves[i] === '0-0-0') {
 652                         hiddenboard.move('O-O-O');
 653                 } else {
 654                         hiddenboard.move(moves[i]);
 655                 }
 656         }
 657         return hiddenboard;
 658 }
 659
 660 /**
 661  * @param {Object} data
 662  * @param {?Object} display_data
 663  */
 664 var update_board = function(current_data, display_data) {
 665         var data = display_data || current_data;
 666
 667         display_lines = [];
 668
 669         // Print the history. This is pretty much the only thing that's
 670         // unconditionally taken from current_data (we're not interested in
 671         // historic history).
 672         if (current_data['position']['pretty_history']) {
 673                 add_pv('start', current_data['position']['pretty_history'], 1, 'W', 8, true);
 674         } else {
 675                 display_lines.push(null);
 676         }
 677         update_history();
 678
 679         // The headline. Names are always fetched from current_data;
 680         // the rest can depend a bit.
 681         var headline;
 682         if (current_data &&
 683             current_data['position']['player_w'] && current_data['position']['player_b']) {
 684                 headline = current_data['position']['player_w'] + '–' +
 685                         current_data['position']['player_b'] + ', analysis';
 686         } else {
 687                 headline = 'Analysis';
 688         }
 689
 690         var last_move;
 691         if (display_data) {
 692                 // Displaying some non-current position, pick out the last move
 693                 // from the history. This will work even if the fetch failed.
 694                 last_move = format_move_with_number(
 695                         current_display_line.pretty_pv[current_display_move],
 696                         Math.floor((current_display_move + 1) / 2) + 1,
 697                         (current_display_move % 2 == 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
 857 /**
 858  * @param {number} num_viewers
 859  */
 860 var update_num_viewers = function(num_viewers) {
 861         if (num_viewers === null) {
 862                 $("#numviewers").text("");
 863         } else if (num_viewers == 1) {
 864                 $("#numviewers").text("You are the only current viewer");
 865         } else {
 866                 $("#numviewers").text(num_viewers + " current viewers");
 867         }
 868 }
 869
 870 var update_clock = function() {
 871         clearTimeout(clock_timer);
 872
 873         var data = displayed_analysis_data || current_analysis_data;
 874         if (data['position']) {
 875                 var result = data['position']['result'];
 876                 if (result === '1-0') {
 877                         $("#whiteclock").text("1");
 878                         $("#blackclock").text("0");
 879                         $("#whiteclock").removeClass("running-clock");
 880                         $("#blackclock").removeClass("running-clock");
 881                         return;
 882                 }
 883                 if (result === '1/2-1/2') {
 884                         $("#whiteclock").text("1/2");
 885                         $("#blackclock").text("1/2");
 886                         $("#whiteclock").removeClass("running-clock");
 887                         $("#blackclock").removeClass("running-clock");
 888                         return;
 889                 }
 890                 if (result === '0-1') {
 891                         $("#whiteclock").text("0");
 892                         $("#blackclock").text("1");
 893                         $("#whiteclock").removeClass("running-clock");
 894                         $("#blackclock").removeClass("running-clock");
 895                         return;
 896                 }
 897         }
 898
 899         var white_clock_ms = null;
 900         var black_clock_ms = null;
 901         var show_seconds = false;
 902
 903         // Static clocks.
 904         if (data['position'] &&
 905             data['position']['white_clock'] &&
 906             data['position']['black_clock']) {
 907                 white_clock_ms = data['position']['white_clock'] * 1000;
 908                 black_clock_ms = data['position']['black_clock'] * 1000;
 909         }
 910
 911         // Dynamic clock (only one, obviously).
 912         var color;
 913         if (data['position']['white_clock_target']) {
 914                 color = "white";
 915                 $("#whiteclock").addClass("running-clock");
 916                 $("#blackclock").removeClass("running-clock");
 917         } else if (data['position']['black_clock_target']) {
 918                 color = "black";
 919                 $("#whiteclock").removeClass("running-clock");
 920                 $("#blackclock").addClass("running-clock");
 921         } else {
 922                 $("#whiteclock").removeClass("running-clock");
 923                 $("#blackclock").removeClass("running-clock");
 924         }
 925         var remaining_ms;
 926         if (color) {
 927                 var now = new Date().getTime() + client_clock_offset_ms;
 928                 remaining_ms = data['position'][color + '_clock_target'] * 1000 - now;
 929                 if (color === "white") {
 930                         white_clock_ms = remaining_ms;
 931                 } else {
 932                         black_clock_ms = remaining_ms;
 933                 }
 934         }
 935
 936         if (white_clock_ms === null || black_clock_ms === null) {
 937                 $("#whiteclock").empty();
 938                 $("#blackclock").empty();
 939                 return;
 940         }
 941
 942         // If either player has ten minutes or less left, add the second counters.
 943         var show_seconds = (white_clock_ms < 60 * 10 * 1000 || black_clock_ms < 60 * 10 * 1000);
 944
 945         if (color) {
 946                 // See when the clock will change next, and update right after that.
 947                 var next_update_ms;
 948                 if (show_seconds) {
 949                         next_update_ms = remaining_ms % 1000 + 100;
 950                 } else {
 951                         next_update_ms = remaining_ms % 60000 + 100;
 952                 }
 953                 clock_timer = setTimeout(update_clock, next_update_ms);
 954         }
 955
 956         $("#whiteclock").text(format_clock(white_clock_ms, show_seconds));
 957         $("#blackclock").text(format_clock(black_clock_ms, show_seconds));
 958 }
 959
 960 /**
 961  * @param {Number} remaining_ms
 962  * @param {boolean} show_seconds
 963  */
 964 var format_clock = function(remaining_ms, show_seconds) {
 965         if (remaining_ms <= 0) {
 966                 if (show_seconds) {
 967                         return "00:00:00";
 968                 } else {
 969                         return "00:00";
 970                 }
 971         }
 972
 973         var remaining = Math.floor(remaining_ms / 1000);
 974         var seconds = remaining % 60;
 975         remaining = (remaining - seconds) / 60;
 976         var minutes = remaining % 60;
 977         remaining = (remaining - minutes) / 60;
 978         var hours = remaining;
 979         if (show_seconds) {
 980                 return format_2d(hours) + ":" + format_2d(minutes) + ":" + format_2d(seconds);
 981         } else {
 982                 return format_2d(hours) + ":" + format_2d(minutes);
 983         }
 984 }
 985
 986 /**
 987  * @param {Number} x
 988  */
 989 var format_2d = function(x) {
 990         if (x >= 10) {
 991                 return x;
 992         } else {
 993                 return "0" + x;
 994         }
 995 }
 996
 997 /**
 998  * @param {string} move
 999  * @param {Number} move_num
1000  * @param {boolean} white_to_play
1001  */
1002 var format_move_with_number = function(move, move_num, white_to_play) {
1003         var ret;
1004         if (white_to_play) {
1005                 ret = (move_num - 1) + '… ';
1006         } else {
1007                 ret = move_num + '. ';
1008         }
1009         ret += move;
1010         return ret;
1011 }
1012
1013 /**
1014  * @param {boolean} sort_by_score
1015  */
1016 var resort_refutation_lines = function(sort_by_score) {
1017         sort_refutation_lines_by_score = sort_by_score;
1018         if (supports_html5_storage()) {
1019                 localStorage['sort_refutation_lines_by_score'] = sort_by_score ? 1 : 0;
1020         }
1021         update_refutation_lines();
1022 }
1023 window['resort_refutation_lines'] = resort_refutation_lines;
1024
1025 /**
1026  * @param {boolean} truncate_history
1027  */
1028 var set_truncate_history = function(truncate_history) {
1029         truncate_display_history = truncate_history;
1030         update_refutation_lines();
1031 }
1032 window['set_truncate_history'] = set_truncate_history;
1033
1034 /**
1035  * @param {number} line_num
1036  * @param {number} move_num
1037  */
1038 var show_line = function(line_num, move_num) {
1039         if (line_num == -1) {
1040                 current_display_line = null;
1041                 current_display_move = null;
1042                 if (displayed_analysis_data) {
1043                         // TODO: Support exiting to history position if we are in an
1044                         // analysis line of a history position.
1045                         displayed_analysis_data = null;
1046                         update_board(current_analysis_data, displayed_analysis_data);
1047                 }
1048         } else {
1049                 current_display_line = display_lines[line_num];
1050                 current_display_move = move_num;
1051         }
1052         current_display_line_is_history = (line_num == 0);
1053
1054         update_historic_analysis();
1055         update_displayed_line();
1056         update_highlight();
1057         redraw_arrows();
1058 }
1059 window['show_line'] = show_line;
1060
1061 var prev_move = function() {
1062         if (current_display_move > -1) {
1063                 --current_display_move;
1064         }
1065         update_historic_analysis();
1066         update_displayed_line();
1067 }
1068 window['prev_move'] = prev_move;
1069
1070 var next_move = function() {
1071         if (current_display_line && current_display_move < current_display_line.pretty_pv.length - 1) {
1072                 ++current_display_move;
1073         }
1074         update_historic_analysis();
1075         update_displayed_line();
1076 }
1077 window['next_move'] = next_move;
1078
1079 var update_historic_analysis = function() {
1080         if (!current_display_line_is_history) {
1081                 return;
1082         }
1083         if (current_display_move == current_display_line.pretty_pv.length - 1) {
1084                 displayed_analysis_data = null;
1085                 update_board(current_analysis_data, displayed_analysis_data);
1086         }
1087
1088         // Fetch old analysis for this line if it exists.
1089         var hiddenboard = chess_from(null, current_display_line.pretty_pv, current_display_move);
1090         var filename = "/history/move" + (current_display_move + 1) + "-" +
1091                 hiddenboard.fen().replace(/ /g, '_').replace(/\//g, '-') + ".json";
1092
1093         $.ajax({
1094                 url: filename
1095         }).done(function(data, textstatus, xhr) {
1096                 displayed_analysis_data = data;
1097                 update_board(current_analysis_data, displayed_analysis_data);
1098         }).fail(function() {
1099                 displayed_analysis_data = {'failed': true};
1100                 update_board(current_analysis_data, displayed_analysis_data);
1101         });
1102 }
1103
1104 /**
1105  * @param {string} fen
1106  */
1107 var update_imbalance = function(fen) {
1108         var hiddenboard = new Chess(fen);
1109         var imbalance = {'k': 0, 'q': 0, 'r': 0, 'b': 0, 'n': 0, 'p': 0};
1110         for (var row = 0; row < 8; ++row) {
1111                 for (var col = 0; col < 8; ++col) {
1112                         var col_text = String.fromCharCode('a1'.charCodeAt(0) + col);
1113                         var row_text = String.fromCharCode('a1'.charCodeAt(1) + row);
1114                         var square = col_text + row_text;
1115                         var contents = hiddenboard.get(square);
1116                         if (contents !== null) {
1117                                 if (contents.color === 'w') {
1118                                         ++imbalance[contents.type];
1119                                 } else {
1120                                         --imbalance[contents.type];
1121                                 }
1122                         }
1123                 }
1124         }
1125         var white_imbalance = '';
1126         var black_imbalance = '';
1127         for (var piece in imbalance) {
1128                 for (var i = 0; i < imbalance[piece]; ++i) {
1129                         white_imbalance += '<img src="img/chesspieces/wikipedia/w' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1130                 }
1131                 for (var i = 0; i < -imbalance[piece]; ++i) {
1132                         black_imbalance += '<img src="img/chesspieces/wikipedia/b' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1133                 }
1134         }
1135         $('#whiteimbalance').html(white_imbalance);
1136         $('#blackimbalance').html(black_imbalance);
1137 }
1138
1139 var update_displayed_line = function() {
1140         if (highlighted_move !== null) {
1141                 highlighted_move.removeClass('highlight');
1142         }
1143         if (current_display_line === null) {
1144                 $("#linenav").hide();
1145                 $("#linemsg").show();
1146                 board.position(fen);
1147                 update_imbalance(fen);
1148                 return;
1149         }
1150
1151         $("#linenav").show();
1152         $("#linemsg").hide();
1153
1154         if (current_display_move <= 0) {
1155                 $("#prevmove").html("Previous");
1156         } else {
1157                 $("#prevmove").html("<a href=\"javascript:prev_move();\">Previous</a></span>");
1158         }
1159         if (current_display_move == current_display_line.pretty_pv.length - 1) {
1160                 $("#nextmove").html("Next");
1161         } else {
1162                 $("#nextmove").html("<a href=\"javascript:next_move();\">Next</a></span>");
1163         }
1164
1165         highlighted_move = $("#automove" + current_display_line.line_number + "-" + current_display_move);
1166         highlighted_move.addClass('highlight');
1167
1168         var hiddenboard = chess_from(current_display_line.start_fen, current_display_line.pretty_pv, current_display_move);
1169         board.position(hiddenboard.fen());
1170         update_imbalance(hiddenboard.fen());
1171 }
1172
1173 /**
1174  * @param {boolean} param_enable_sound
1175  */
1176 var set_sound = function(param_enable_sound) {
1177         enable_sound = param_enable_sound;
1178         if (enable_sound) {
1179                 $("#soundon").html("<strong>On</strong>");
1180                 $("#soundoff").html("<a href=\"javascript:set_sound(false)\">Off</a>");
1181
1182                 // Seemingly at least Firefox prefers MP3 over Opus; tell it otherwise,
1183                 // and also preload the file since the user has selected audio.
1184                 var ding = document.getElementById('ding');
1185                 if (ding && ding.canPlayType && ding.canPlayType('audio/ogg; codecs="opus"') === 'probably') {
1186                         ding.src = 'ding.opus';
1187                         ding.load();
1188                 }
1189         } else {
1190                 $("#soundon").html("<a href=\"javascript:set_sound(true)\">On</a>");
1191                 $("#soundoff").html("<strong>Off</strong>");
1192         }
1193         if (supports_html5_storage()) {
1194                 localStorage['enable_sound'] = enable_sound ? 1 : 0;
1195         }
1196 }
1197 window['set_sound'] = set_sound;
1198
1199 var init = function() {
1200         unique = get_unique();
1201
1202         // Load settings from HTML5 local storage if available.
1203         if (supports_html5_storage() && localStorage['enable_sound']) {
1204                 set_sound(parseInt(localStorage['enable_sound']));
1205         } else {
1206                 set_sound(false);
1207         }
1208         if (supports_html5_storage() && localStorage['sort_refutation_lines_by_score']) {
1209                 sort_refutation_lines_by_score = parseInt(localStorage['sort_refutation_lines_by_score']);
1210         } else {
1211                 sort_refutation_lines_by_score = true;
1212         }
1213
1214         // Create board.
1215         board = new window.ChessBoard('board', 'start');
1216
1217         request_update();
1218         $(window).resize(function() {
1219                 board.resize();
1220                 update_highlight();
1221                 redraw_arrows();
1222         });
1223         $(window).keyup(function(event) {
1224                 if (event.which == 39) {
1225                         next_move();
1226                 } else if (event.which == 37) {
1227                         prev_move();
1228                 }
1229         });
1230 };
1231 $(document).ready(init);
1232
1233 })();