4 * Version of this script. If the server returns a version larger than
5 * this, it is a sign we should reload to upgrade ourselves.
10 var SCRIPT_VERSION = 2016032201;
13 * The current backend URL.
18 var backend_url = "/analysis.pl";
19 var backend_hash_url = "/hash";
21 /** @type {window.ChessBoard} @private */
24 /** @type {boolean} @private */
25 var board_is_animating = false;
28 * The most recent analysis data we have from the server
29 * (about the most recent position).
33 var current_analysis_data = null;
36 * If we are displaying previous analysis or from hash, this is non-null,
37 * and will override most of current_analysis_data.
42 var displayed_analysis_data = null;
45 * Games currently in progress, if any.
56 var current_games = null;
71 /** @type {Array.<Array.<boolean>>} */
72 var occupied_by_arrows = [];
74 /** Currently displayed refutation lines (on-screen).
75 * Can either come from the current_analysis_data, displayed_analysis_data,
76 * or hash_refutation_lines.
78 var refutation_lines = [];
80 /** Refutation lines from current hash probe.
82 * If non-null, will override refutation lines from the base position.
83 * Note that these are relative to display_fen, not base_fen.
85 var hash_refutation_lines = null;
87 /** @type {!number} @private */
90 /** @type {!string} @private */
93 /** @type {number} @private */
96 /** @type {boolean} @private */
97 var sort_refutation_lines_by_score = true;
99 /** @type {boolean} @private */
100 var truncate_display_history = true;
102 /** @type {!string|undefined} @private */
103 var highlight_from = undefined;
105 /** @type {!string|undefined} @private */
106 var highlight_to = undefined;
108 /** The HTML object of the move currently being highlighted (in red).
111 var highlighted_move = null;
113 /** Currently suggested/recommended move when dragging.
114 * @type {?{from: !string, to: !string}}
117 var recommended_move = null;
119 /** If reverse-dragging (dragging from the destination square to the
120 * source square), the destination square.
124 var reverse_dragging_from = null;
126 /** @type {?number} @private */
129 /** @type {boolean} @private */
130 var enable_sound = false;
133 * Our best estimate of how many milliseconds we need to add to
134 * new Date() to get the true UTC time. Calibrated against the
140 var client_clock_offset_ms = null;
142 var clock_timer = null;
144 /** The current position being analyzed, represented as a FEN string.
145 * Note that this is not necessarily the same as display_fen.
151 /** The current position on the board, represented as a FEN string.
152 * Note that board.fen() does not contain e.g. who is to play.
156 var display_fen = null;
160 * pretty_pv: Array.<string>,
164 * start_display_move_num: number
167 * "start_display_move_num" is the (half-)move number to start displaying the PV at.
168 * "score" is also evaluated at this point.
171 /** All PVs that we currently know of.
173 * Element 0 is history (or null if no history).
174 * Element 1 is current main PV, or explored line if nowhere else on the screen.
175 * All remaining elements are refutation lines (multi-PV).
177 * @type {Array.<DisplayLine>}
180 var display_lines = [];
182 /** @type {?DisplayLine} @private */
183 var current_display_line = null;
185 /** @type {boolean} @private */
186 var current_display_line_is_history = false;
188 /** @type {?number} @private */
189 var current_display_move = null;
192 * The current backend request to get main analysis (not history), if any,
193 * so that we can abort it.
198 var current_analysis_xhr = null;
201 * The current timer to fire off a request to get main analysis (not history),
202 * if any, so that we can abort it.
207 var current_analysis_request_timer = null;
210 * The current backend request to get historic data, if any.
215 var current_historic_xhr = null;
218 * The current backend request to get hash probes, if any, so that we can abort it.
223 var current_hash_xhr = null;
226 * The current timer to display hash probe information (it could be waiting on the
227 * board to stop animating), if any, so that we can abort it.
232 var current_hash_display_timer = null;
234 var supports_html5_storage = function() {
236 return 'localStorage' in window && window['localStorage'] !== null;
242 // Make the unique token persistent so people refreshing the page won't count twice.
243 // Of course, you can never fully protect against people deliberately wanting to spam.
244 var get_unique = function() {
245 var use_local_storage = supports_html5_storage();
246 if (use_local_storage && localStorage['unique']) {
247 return localStorage['unique'];
249 var unique = Math.random();
250 if (use_local_storage) {
251 localStorage['unique'] = unique;
256 var request_update = function() {
257 current_analysis_request_timer = null;
259 current_analysis_xhr = $.ajax({
260 url: backend_url + "?ims=" + ims + "&unique=" + unique
261 }).done(function(data, textstatus, xhr) {
262 sync_server_clock(xhr.getResponseHeader('Date'));
263 ims = xhr.getResponseHeader('X-RGLM');
264 var num_viewers = xhr.getResponseHeader('X-RGNV');
266 if (Array.isArray(data)) {
267 new_data = JSON.parse(JSON.stringify(current_analysis_data));
268 JSON_delta.patch(new_data, data);
273 var minimum_version = xhr.getResponseHeader('X-RGMV');
274 if (minimum_version && minimum_version > SCRIPT_VERSION) {
275 // Upgrade to latest version with a force-reload.
276 location.reload(true);
279 possibly_play_sound(current_analysis_data, new_data);
280 current_analysis_data = new_data;
282 update_num_viewers(num_viewers);
285 current_analysis_request_timer = setTimeout(function() { request_update(); }, 100);
286 }).fail(function(jqXHR, textStatus, errorThrown) {
287 if (textStatus === "abort") {
288 // Aborted because we are switching backends. Abandon and don't retry,
289 // because another one is already started for us.
291 // Backend error or similar. Wait ten seconds, then try again.
292 current_analysis_request_timer = setTimeout(function() { request_update(); }, 10000);
297 var possibly_play_sound = function(old_data, new_data) {
301 if (old_data === null) {
304 var ding = document.getElementById('ding');
305 if (ding && ding.play) {
306 if (old_data['position'] && old_data['position']['fen'] &&
307 new_data['position'] && new_data['position']['fen'] &&
308 (old_data['position']['fen'] !== new_data['position']['fen'] ||
309 old_data['position']['move_num'] !== new_data['position']['move_num'])) {
316 * @type {!string} server_date_string
318 var sync_server_clock = function(server_date_string) {
319 var server_time_ms = new Date(server_date_string).getTime();
320 var client_time_ms = new Date().getTime();
321 var estimated_offset_ms = server_time_ms - client_time_ms;
323 // In order not to let the noise move us too much back and forth
324 // (the server only has one-second resolution anyway), we only
325 // change an existing skew if we are at least five seconds off.
326 if (client_clock_offset_ms === null ||
327 Math.abs(estimated_offset_ms - client_clock_offset_ms) > 5000) {
328 client_clock_offset_ms = estimated_offset_ms;
332 var clear_arrows = function() {
333 for (var i = 0; i < arrows.length; ++i) {
335 if (arrows[i].svg.parentElement) {
336 arrows[i].svg.parentElement.removeChild(arrows[i].svg);
338 delete arrows[i].svg;
343 occupied_by_arrows = [];
344 for (var y = 0; y < 8; ++y) {
345 occupied_by_arrows.push([false, false, false, false, false, false, false, false]);
349 var redraw_arrows = function() {
350 for (var i = 0; i < arrows.length; ++i) {
351 position_arrow(arrows[i]);
355 /** @param {!number} x
358 var sign = function(x) {
368 /** See if drawing this arrow on the board would cause unduly amount of confusion.
369 * @param {!string} from The square the arrow is from (e.g. e4).
370 * @param {!string} to The square the arrow is to (e.g. e4).
373 var interfering_arrow = function(from, to) {
374 var from_col = from.charCodeAt(0) - "a1".charCodeAt(0);
375 var from_row = from.charCodeAt(1) - "a1".charCodeAt(1);
376 var to_col = to.charCodeAt(0) - "a1".charCodeAt(0);
377 var to_row = to.charCodeAt(1) - "a1".charCodeAt(1);
379 occupied_by_arrows[from_row][from_col] = true;
381 // Knight move: Just check that we haven't been at the destination before.
382 if ((Math.abs(to_col - from_col) == 2 && Math.abs(to_row - from_row) == 1) ||
383 (Math.abs(to_col - from_col) == 1 && Math.abs(to_row - from_row) == 2)) {
384 return occupied_by_arrows[to_row][to_col];
387 // Sliding piece: Check if anything except the from-square is seen before.
388 var dx = sign(to_col - from_col);
389 var dy = sign(to_row - from_row);
395 if (occupied_by_arrows[y][x]) {
398 occupied_by_arrows[y][x] = true;
399 } while (x != to_col || y != to_row);
404 /** Find a point along the coordinate system given by the given line,
405 * <t> units forward from the start of the line, <u> units to the right of it.
406 * @param {!number} x1
407 * @param {!number} x2
408 * @param {!number} y1
409 * @param {!number} y2
412 * @return {!string} The point in "x y" form, suitable for SVG paths.
414 var point_from_start = function(x1, y1, x2, y2, t, u) {
418 var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
422 var x = x1 + dx * t + dy * u;
423 var y = y1 + dy * t - dx * u;
427 /** Find a point along the coordinate system given by the given line,
428 * <t> units forward from the end of the line, <u> units to the right of it.
429 * @param {!number} x1
430 * @param {!number} x2
431 * @param {!number} y1
432 * @param {!number} y2
435 * @return {!string} The point in "x y" form, suitable for SVG paths.
437 var point_from_end = function(x1, y1, x2, y2, t, u) {
441 var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
445 var x = x2 + dx * t + dy * u;
446 var y = y2 + dy * t - dx * u;
450 var position_arrow = function(arrow) {
452 if (arrow.svg.parentElement) {
453 arrow.svg.parentElement.removeChild(arrow.svg);
457 if (current_display_line !== null && !current_display_line_is_history) {
461 var pos = $(".square-a8").position();
463 var zoom_factor = $("#board").width() / 400.0;
464 var line_width = arrow.line_width * zoom_factor;
465 var arrow_size = arrow.arrow_size * zoom_factor;
467 var square_width = $(".square-a8").width();
468 var from_y = (7 - arrow.from_row + 0.5)*square_width;
469 var to_y = (7 - arrow.to_row + 0.5)*square_width;
470 var from_x = (arrow.from_col + 0.5)*square_width;
471 var to_x = (arrow.to_col + 0.5)*square_width;
473 var SVG_NS = "http://www.w3.org/2000/svg";
474 var XHTML_NS = "http://www.w3.org/1999/xhtml";
475 var svg = document.createElementNS(SVG_NS, "svg");
476 svg.setAttribute("width", /** @type{number} */ ($("#board").width()));
477 svg.setAttribute("height", /** @type{number} */ ($("#board").height()));
478 svg.setAttribute("style", "position: absolute");
479 svg.setAttribute("position", "absolute");
480 svg.setAttribute("version", "1.1");
481 svg.setAttribute("class", "c1");
482 svg.setAttribute("xmlns", XHTML_NS);
490 var outline = document.createElementNS(SVG_NS, "path");
491 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));
492 outline.setAttribute("xmlns", XHTML_NS);
493 outline.setAttribute("stroke", "#666");
494 outline.setAttribute("stroke-width", line_width + 2);
495 outline.setAttribute("fill", "none");
496 svg.appendChild(outline);
498 var path = document.createElementNS(SVG_NS, "path");
499 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));
500 path.setAttribute("xmlns", XHTML_NS);
501 path.setAttribute("stroke", arrow.fg_color);
502 path.setAttribute("stroke-width", line_width);
503 path.setAttribute("fill", "none");
504 svg.appendChild(path);
506 // Then the arrow head.
507 var head = document.createElementNS(SVG_NS, "path");
508 head.setAttribute("d",
509 "M " + point_from_end(x1, y1, x2, y2, 0, 0) +
510 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, -arrow_size / 2) +
511 " L " + point_from_end(x1, y1, x2, y2, -arrow_size * .623, 0.0) +
512 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, arrow_size / 2) +
513 " L " + point_from_end(x1, y1, x2, y2, 0, 0));
514 head.setAttribute("xmlns", XHTML_NS);
515 head.setAttribute("stroke", "#000");
516 head.setAttribute("stroke-width", "1");
517 head.setAttribute("fill", arrow.fg_color);
518 svg.appendChild(head);
520 $(svg).css({ top: pos.top, left: pos.left, 'pointer-events': 'none' });
521 document.body.appendChild(svg);
526 * @param {!string} from_square
527 * @param {!string} to_square
528 * @param {!string} fg_color
529 * @param {number} line_width
530 * @param {number} arrow_size
532 var create_arrow = function(from_square, to_square, fg_color, line_width, arrow_size) {
533 var from_col = from_square.charCodeAt(0) - "a1".charCodeAt(0);
534 var from_row = from_square.charCodeAt(1) - "a1".charCodeAt(1);
535 var to_col = to_square.charCodeAt(0) - "a1".charCodeAt(0);
536 var to_row = to_square.charCodeAt(1) - "a1".charCodeAt(1);
544 line_width: line_width,
545 arrow_size: arrow_size,
549 position_arrow(arrow);
553 // Note: invert is ignored.
554 var compare_by_sort_key = function(refutation_lines, invert, a, b) {
555 var ska = refutation_lines[a]['sort_key'];
556 var skb = refutation_lines[b]['sort_key'];
557 if (ska < skb) return -1;
558 if (ska > skb) return 1;
562 var compare_by_score = function(refutation_lines, invert, a, b) {
563 var sa = compute_score_sort_key(refutation_lines[b]['score'], invert);
564 var sb = compute_score_sort_key(refutation_lines[a]['score'], invert);
569 * Fake multi-PV using the refutation lines. Find all “relevant” moves,
570 * sorted by quality, descending.
572 * @param {!Object} data
573 * @param {number} margin The maximum number of centipawns worse than the
574 * best move can be and still be included.
575 * @param {boolean} margin Whether black is to play.
576 * @return {Array.<string>} The UCI representation (e.g. e1g1) of all
577 * moves, in score order.
579 var find_nonstupid_moves = function(data, margin, invert) {
580 // First of all, if there are any moves that are more than 0.5 ahead of
581 // the primary move, the refutation lines are probably bunk, so just
583 var best_score = undefined;
584 var pv_score = undefined;
585 for (var move in data['refutation_lines']) {
586 var score = compute_score_sort_key(data['refutation_lines'][move]['score'], invert);
587 if (move == data['pv_uci'][0]) {
590 if (best_score === undefined || score > best_score) {
593 if (!(data['refutation_lines'][move]['depth'] >= 8)) {
598 if (best_score - pv_score > 50) {
602 // Now find all moves that are within “margin” of the best score.
603 // The PV move will always be first.
605 for (var move in data['refutation_lines']) {
606 var score = compute_score_sort_key(data['refutation_lines'][move]['score'], invert);
607 if (move != data['pv_uci'][0] && best_score - score <= margin) {
611 moves = moves.sort(function(a, b) { return compare_by_score(data['refutation_lines'], data['position']['toplay'] === 'B', a, b) });
612 moves.unshift(data['pv_uci'][0]);
621 var thousands = function(x) {
622 return String(x).split('').reverse().join('').replace(/(\d{3}\B)/g, '$1,').split('').reverse().join('');
626 * @param {!string} start_fen
627 * @param {Array.<string>} pretty_pv
628 * @param {number} move_num
629 * @param {!string} toplay
630 * @param {!string} score
631 * @param {number} start_display_move_num
632 * @param {number=} opt_limit
633 * @param {boolean=} opt_showlast
635 var add_pv = function(start_fen, pretty_pv, move_num, toplay, score, start_display_move_num, opt_limit, opt_showlast) {
637 start_fen: start_fen,
638 pretty_pv: pretty_pv,
639 move_num: parseInt(move_num),
642 start_display_move_num: start_display_move_num
644 return print_pv(display_lines.length - 1, opt_limit, opt_showlast);
648 * @param {number} line_num
649 * @param {number=} opt_limit If set, show at most this number of moves.
650 * @param {boolean=} opt_showlast If limit is set, show the last moves instead of the first ones.
652 var print_pv = function(line_num, opt_limit, opt_showlast) {
653 var display_line = display_lines[line_num];
654 var pretty_pv = display_line.pretty_pv;
655 var move_num = display_line.move_num;
656 var toplay = display_line.toplay;
658 // Truncate PV at the start if needed.
659 var start_display_move_num = display_line.start_display_move_num;
660 if (start_display_move_num > 0) {
661 pretty_pv = pretty_pv.slice(start_display_move_num);
662 var to_add = start_display_move_num;
663 if (toplay === 'B') {
668 if (to_add % 2 == 1) {
672 move_num += to_add / 2;
677 if (opt_limit && opt_showlast && pretty_pv.length > opt_limit) {
678 // Truncate the PV at the beginning (instead of at the end).
679 // We assume here that toplay is 'W'. We also assume that if
680 // opt_showlast is set, then it is the history, and thus,
681 // the UI should be to expand the history.
682 pv = '(<a class="move" href="javascript:collapse_history(false)">…</a>) ';
683 i = pretty_pv.length - opt_limit;
688 } else if (toplay == 'B' && pretty_pv.length > 0) {
689 var move = "<a class=\"move\" id=\"automove" + line_num + "-0\" href=\"javascript:show_line(" + line_num + ", " + 0 + ");\">" + pretty_pv[0] + "</a>";
690 pv = move_num + '. … ' + move;
695 for ( ; i < pretty_pv.length; ++i) {
696 var move = "<a class=\"move\" id=\"automove" + line_num + "-" + i + "\" href=\"javascript:show_line(" + line_num + ", " + i + ");\">" + pretty_pv[i] + "</a>";
699 if (i > opt_limit && !opt_showlast) {
705 pv += move_num + '. ' + move;
716 /** Update the highlighted to/from squares on the board.
717 * Based on the global "highlight_from" and "highlight_to" variables.
719 var update_board_highlight = function() {
720 $("#board").find('.square-55d63').removeClass('nonuglyhighlight');
721 if ((current_display_line === null || current_display_line_is_history) &&
722 highlight_from !== undefined && highlight_to !== undefined) {
723 $("#board").find('.square-' + highlight_from).addClass('nonuglyhighlight');
724 $("#board").find('.square-' + highlight_to).addClass('nonuglyhighlight');
728 var update_history = function() {
729 if (display_lines[0] === null || display_lines[0].pretty_pv.length == 0) {
730 $("#history").html("No history");
731 } else if (truncate_display_history) {
732 $("#history").html(print_pv(0, 8, true));
735 '(<a class="move" href="javascript:collapse_history(true)">collapse</a>) ' +
741 * @param {!boolean} truncate_history
743 var collapse_history = function(truncate_history) {
744 truncate_display_history = truncate_history;
747 window['collapse_history'] = collapse_history;
749 /** Update the HTML display of multi-PV from the global "refutation_lines".
751 * Also recreates the global "display_lines".
753 var update_refutation_lines = function() {
754 if (base_fen === null) {
757 if (display_lines.length > 2) {
758 // Truncate so that only the history and PV is left.
759 display_lines = [ display_lines[0], display_lines[1] ];
761 var tbl = $("#refutationlines");
764 // Find out where the lines start from.
766 var start_display_move_num = 0;
767 if (hash_refutation_lines) {
768 base_line = current_display_line.pretty_pv.slice(0, current_display_move + 1);
769 start_display_move_num = base_line.length;
773 for (var move in refutation_lines) {
777 var invert = (toplay === 'B');
778 if (current_display_line && current_display_move % 2 == 0) {
781 var compare = sort_refutation_lines_by_score ? compare_by_score : compare_by_sort_key;
782 moves = moves.sort(function(a, b) { return compare(refutation_lines, invert, a, b) });
783 for (var i = 0; i < moves.length; ++i) {
784 var line = refutation_lines[moves[i]];
786 var tr = document.createElement("tr");
788 var move_td = document.createElement("td");
789 tr.appendChild(move_td);
790 $(move_td).addClass("move");
792 if (line['pv_pretty'].length == 0) {
793 // Not found, so just make a one-move PV.
794 var move = "<a class=\"move\" href=\"javascript:show_line(" + display_lines.length + ", " + 0 + ");\">" + line['pretty_move'] + "</a>";
795 $(move_td).html(move);
796 var score_td = document.createElement("td");
798 $(score_td).addClass("score");
799 $(score_td).text("—");
800 tr.appendChild(score_td);
802 var depth_td = document.createElement("td");
803 tr.appendChild(depth_td);
804 $(depth_td).addClass("depth");
805 $(depth_td).text("—");
807 var pv_td = document.createElement("td");
808 tr.appendChild(pv_td);
809 $(pv_td).addClass("pv");
810 $(pv_td).html(add_pv(base_fen, base_line.concat([ line['pretty_move'] ]), move_num, toplay, line['score'], start_display_move_num));
816 var move = "<a class=\"move\" href=\"javascript:show_line(" + display_lines.length + ", " + 0 + ");\">" + line['pretty_move'] + "</a>";
817 $(move_td).html(move);
819 var score_td = document.createElement("td");
820 tr.appendChild(score_td);
821 $(score_td).addClass("score");
822 $(score_td).text(format_short_score(line['score']));
824 var depth_td = document.createElement("td");
825 tr.appendChild(depth_td);
826 $(depth_td).addClass("depth");
827 if (line['depth'] && line['depth'] >= 0) {
828 $(depth_td).text("d" + line['depth']);
830 $(depth_td).text("—");
833 var pv_td = document.createElement("td");
834 tr.appendChild(pv_td);
835 $(pv_td).addClass("pv");
836 $(pv_td).html(add_pv(base_fen, base_line.concat(line['pv_pretty']), move_num, toplay, line['score'], start_display_move_num, 10));
841 // Make one of the links clickable and the other nonclickable.
842 if (sort_refutation_lines_by_score) {
843 $("#sortbyscore0").html("<a href=\"javascript:resort_refutation_lines(false)\">Move</a>");
844 $("#sortbyscore1").html("<strong>Score</strong>");
846 $("#sortbyscore0").html("<strong>Move</strong>");
847 $("#sortbyscore1").html("<a href=\"javascript:resort_refutation_lines(true)\">Score</a>");
850 // Update the move highlight, as we've rewritten all the HTML.
851 update_move_highlight();
855 * Create a Chess.js board object, containing the given position plus the given moves,
856 * up to the given limit.
858 * @param {?string} fen
859 * @param {Array.<string>} moves
860 * @param {number} last_move
862 var chess_from = function(fen, moves, last_move) {
863 var hiddenboard = new Chess();
865 hiddenboard.load(fen);
867 for (var i = 0; i <= last_move; ++i) {
868 if (moves[i] === '0-0') {
869 hiddenboard.move('O-O');
870 } else if (moves[i] === '0-0-0') {
871 hiddenboard.move('O-O-O');
873 hiddenboard.move(moves[i]);
879 var update_game_list = function(games) {
880 $("#games").text("");
881 if (games === null) {
885 var games_div = document.getElementById('games');
886 for (var game_num = 0; game_num < games.length; ++game_num) {
887 var game = games[game_num];
888 var game_span = document.createElement("span");
889 game_span.setAttribute("class", "game");
891 var game_name = document.createTextNode(game['name']);
892 if (game['url'] === backend_url) {
894 game_span.appendChild(game_name);
897 if (current_analysis_data['position']['result']) {
898 score = " (" + current_analysis_data['position']['result'] + ")";
900 score = " (" + format_short_score(current_analysis_data['score']) + ")";
902 game_span.appendChild(document.createTextNode(score));
905 var game_a = document.createElement("a");
906 game_a.setAttribute("href", "#" + game['id']);
907 game_a.appendChild(game_name);
908 game_span.appendChild(game_a);
911 if (game['result']) {
912 score = " (" + game['result'] + ")";
914 score = " (" + format_short_score(game['score']) + ")";
916 game_span.appendChild(document.createTextNode(score));
919 games_div.appendChild(game_span);
924 * Try to find a running game that matches with the current hash,
925 * and switch to it if we're not already displaying it.
927 var possibly_switch_game_from_hash = function() {
928 if (current_games === null) {
932 var hash = window.location.hash.replace(/^#/,'');
933 for (var i = 0; i < current_games.length; ++i) {
934 if (current_games[i]['id'] === hash) {
935 if (backend_url !== current_games[i]['url']) {
936 switch_backend(current_games[i]['url'], current_games[i]['hashurl']);
943 /** Update all the HTML on the page, based on current global state.
945 var update_board = function() {
946 var data = displayed_analysis_data || current_analysis_data;
947 var current_data = current_analysis_data; // Convenience alias.
951 // Print the history. This is pretty much the only thing that's
952 // unconditionally taken from current_data (we're not interested in
953 // historic history).
954 if (current_data['position']['pretty_history']) {
955 add_pv('start', current_data['position']['pretty_history'], 1, 'W', null, 0, 8, true);
957 display_lines.push(null);
961 // Games currently in progress, if any.
962 if (current_data['games']) {
963 current_games = current_data['games'];
964 possibly_switch_game_from_hash();
966 current_games = null;
968 update_game_list(current_games);
970 // The headline. Names are always fetched from current_data;
971 // the rest can depend a bit.
974 current_data['position']['player_w'] && current_data['position']['player_b']) {
975 headline = current_data['position']['player_w'] + '–' +
976 current_data['position']['player_b'] + ', analysis';
978 headline = 'Analysis';
981 // Credits, where applicable. Note that we don't want the footer to change a lot
982 // when e.g. viewing history, so if any of these changed during the game,
983 // use the current one still.
984 if (current_data['using_lomonosov']) {
985 $("#lomonosov").show();
987 $("#lomonosov").hide();
990 // Credits: The engine name/version.
991 if (current_data['engine'] && current_data['engine']['name'] !== null) {
992 $("#engineid").text(current_data['engine']['name']);
995 // Credits: The engine URL.
996 if (current_data['engine'] && current_data['engine']['url']) {
997 $("#engineid").attr("href", current_data['engine']['url']);
999 $("#engineid").removeAttr("href");
1002 // Credits: Engine details.
1003 if (current_data['engine'] && current_data['engine']['details']) {
1004 $("#enginedetails").text(" (" + current_data['engine']['details'] + ")");
1006 $("#enginedetails").text("");
1009 // Credits: Move source, possibly with URL.
1010 if (current_data['move_source'] && current_data['move_source_url']) {
1011 $("#movesource").text("Moves provided by ");
1012 var movesource_a = document.createElement("a");
1013 movesource_a.setAttribute("href", current_data['move_source_url']);
1014 var movesource_text = document.createTextNode(current_data['move_source']);
1015 movesource_a.appendChild(movesource_text);
1016 var movesource_period = document.createTextNode(".");
1017 document.getElementById("movesource").appendChild(movesource_a);
1018 document.getElementById("movesource").appendChild(movesource_period);
1019 } else if (current_data['move_source']) {
1020 $("#movesource").text("Moves provided by " + current_data['move_source'] + ".");
1022 $("#movesource").text("");
1026 if (displayed_analysis_data) {
1027 // Displaying some non-current position, pick out the last move
1028 // from the history. This will work even if the fetch failed.
1029 last_move = format_halfmove_with_number(
1030 current_display_line.pretty_pv[current_display_move],
1031 current_display_move + 1);
1032 headline += ' after ' + last_move;
1033 } else if (data['position']['last_move'] !== 'none') {
1034 last_move = format_move_with_number(
1035 data['position']['last_move'],
1036 data['position']['move_num'],
1037 data['position']['toplay'] == 'W');
1038 headline += ' after ' + last_move;
1042 $("#headline").text(headline);
1044 // The <title> contains a very brief headline.
1045 var title_elems = [];
1046 if (data['position'] && data['position']['result']) {
1047 title_elems.push(data['position']['result']);
1048 } else if (data['score']) {
1049 title_elems.push(format_short_score(data['score']));
1051 if (last_move !== null) {
1052 title_elems.push(last_move);
1055 if (title_elems.length != 0) {
1056 document.title = '(' + title_elems.join(', ') + ') analysis.sesse.net';
1058 document.title = 'analysis.sesse.net';
1061 // The last move (shown by highlighting the from and to squares).
1062 if (data['position'] && data['position']['last_move_uci']) {
1063 highlight_from = data['position']['last_move_uci'].substr(0, 2);
1064 highlight_to = data['position']['last_move_uci'].substr(2, 2);
1065 } else if (current_display_line_is_history && current_display_move >= 0) {
1066 // We don't have historic analysis for this position, but we
1067 // can reconstruct what the last move was by just replaying
1069 var hiddenboard = chess_from(null, current_display_line.pretty_pv, current_display_move);
1070 var moves = hiddenboard.history({ verbose: true });
1071 var last_move = moves.pop();
1072 highlight_from = last_move.from;
1073 highlight_to = last_move.to;
1075 highlight_from = highlight_to = undefined;
1077 update_board_highlight();
1079 if (data['failed']) {
1080 $("#score").text("No analysis for this move");
1081 $("#pvtitle").text("PV:");
1083 $("#searchstats").html(" ");
1084 $("#refutationlines").empty();
1085 $("#whiteclock").empty();
1086 $("#blackclock").empty();
1087 refutation_lines = [];
1088 update_refutation_lines();
1090 update_displayed_line();
1091 update_move_highlight();
1098 if (current_display_line && !current_display_line_is_history) {
1099 if (current_display_line.score) {
1100 $("#score").text(format_long_score(current_display_line.score));
1102 $("#score").text("No score for this move");
1104 } else if (data['score']) {
1105 $("#score").text(format_long_score(data['score']));
1108 // The search stats.
1109 if (data['searchstats']) {
1110 $("#searchstats").html(data['searchstats']);
1111 } else if (data['tablebase'] == 1) {
1112 $("#searchstats").text("Tablebase result");
1113 } else if (data['nodes'] && data['nps'] && data['depth']) {
1114 var stats = thousands(data['nodes']) + ' nodes, ' + thousands(data['nps']) + ' nodes/sec, depth ' + data['depth'] + ' ply';
1115 if (data['seldepth']) {
1116 stats += ' (' + data['seldepth'] + ' selective)';
1118 if (data['tbhits'] && data['tbhits'] > 0) {
1119 if (data['tbhits'] == 1) {
1120 stats += ', one Syzygy hit';
1122 stats += ', ' + thousands(data['tbhits']) + ' Syzygy hits';
1126 $("#searchstats").text(stats);
1128 $("#searchstats").text("");
1131 // Update the board itself.
1132 base_fen = data['position']['fen'];
1133 update_displayed_line();
1136 $("#pvtitle").text("PV:");
1137 $("#pv").html(add_pv(data['position']['fen'], data['pv_pretty'], data['position']['move_num'], data['position']['toplay'], data['score'], 0));
1139 // Update the PV arrow.
1141 if (data['pv_uci'].length >= 1) {
1142 // draw a continuation arrow as long as it's the same piece
1143 for (var i = 0; i < data['pv_uci'].length; i += 2) {
1144 var from = data['pv_uci'][i].substr(0, 2);
1145 var to = data['pv_uci'][i].substr(2,4);
1146 if ((i >= 2 && from != data['pv_uci'][i - 2].substr(2, 2)) ||
1147 interfering_arrow(from, to)) {
1150 create_arrow(from, to, '#f66', 6, 20);
1153 var alt_moves = find_nonstupid_moves(data, 30, data['position']['toplay'] === 'B');
1154 for (var i = 1; i < alt_moves.length && i < 3; ++i) {
1155 create_arrow(alt_moves[i].substr(0, 2),
1156 alt_moves[i].substr(2, 2), '#f66', 1, 10);
1160 // See if all semi-reasonable moves have only one possible response.
1161 if (data['pv_uci'].length >= 2) {
1162 var nonstupid_moves = find_nonstupid_moves(data, 300, data['position']['toplay'] === 'B');
1163 var response = data['pv_uci'][1];
1164 for (var i = 0; i < nonstupid_moves.length; ++i) {
1165 if (nonstupid_moves[i] == data['pv_uci'][0]) {
1166 // ignore the PV move for refutation lines.
1169 if (!data['refutation_lines'] ||
1170 !data['refutation_lines'][nonstupid_moves[i]] ||
1171 !data['refutation_lines'][nonstupid_moves[i]]['pv_uci'] ||
1172 data['refutation_lines'][nonstupid_moves[i]]['pv_uci'].length < 1) {
1173 // Incomplete PV, abort.
1174 response = undefined;
1177 var this_response = data['refutation_lines'][nonstupid_moves[i]]['pv_uci'][1];
1178 if (response !== this_response) {
1179 // Different response depending on lines, abort.
1180 response = undefined;
1185 if (nonstupid_moves.length > 0 && response !== undefined) {
1186 create_arrow(response.substr(0, 2),
1187 response.substr(2, 2), '#66f', 6, 20);
1191 // Update the refutation lines.
1192 base_fen = data['position']['fen'];
1193 move_num = parseInt(data['position']['move_num']);
1194 toplay = data['position']['toplay'];
1195 refutation_lines = hash_refutation_lines || data['refutation_lines'];
1196 update_refutation_lines();
1198 // Update the sparkline last, since its size depends on how everything else reflowed.
1199 update_sparkline(data);
1202 var update_sparkline = function(data) {
1203 if (data && data['score_history']) {
1204 var first_move_num = undefined;
1205 for (var halfmove_num in data['score_history']) {
1206 halfmove_num = parseInt(halfmove_num);
1207 if (first_move_num === undefined || halfmove_num < first_move_num) {
1208 first_move_num = halfmove_num;
1211 if (first_move_num !== undefined) {
1212 var last_move_num = data['position']['move_num'] * 2 - 3;
1213 if (data['position']['toplay'] === 'B') {
1217 // Possibly truncate some moves if we don't have enough width.
1218 // FIXME: Sometimes width() for #scorecontainer (and by extent,
1219 // #scoresparkcontainer) on Chrome for mobile seems to start off
1220 // at something very small, and then suddenly snap back into place.
1222 var max_moves = Math.floor($("#scoresparkcontainer").width() / 5) - 5;
1223 if (last_move_num - first_move_num > max_moves) {
1224 first_move_num = last_move_num - max_moves;
1227 var min_score = -100;
1228 var max_score = 100;
1229 var last_score = null;
1231 for (var halfmove_num = first_move_num; halfmove_num <= last_move_num; ++halfmove_num) {
1232 if (data['score_history'][halfmove_num]) {
1233 var score = compute_plot_score(data['score_history'][halfmove_num]);
1235 if (score < min_score) min_score = score;
1236 if (score > max_score) max_score = score;
1238 scores.push(last_score);
1240 if (data['score']) {
1241 scores.push(compute_plot_score(data['score']));
1243 // FIXME: at some widths, calling sparkline() seems to push
1244 // #scorecontainer under the board.
1245 $("#scorespark").sparkline(scores, {
1248 chartRangeMin: min_score,
1249 chartRangeMax: max_score,
1250 tooltipFormatter: function(sparkline, options, fields) {
1251 return format_tooltip(data, fields[0].offset + first_move_num);
1255 $("#scorespark").text("");
1258 $("#scorespark").text("");
1263 * @param {number} num_viewers
1265 var update_num_viewers = function(num_viewers) {
1266 if (num_viewers === null) {
1267 $("#numviewers").text("");
1268 } else if (num_viewers == 1) {
1269 $("#numviewers").text("You are the only current viewer");
1271 $("#numviewers").text(num_viewers + " current viewers");
1275 var update_clock = function() {
1276 clearTimeout(clock_timer);
1278 var data = displayed_analysis_data || current_analysis_data;
1279 if (data['position']) {
1280 var result = data['position']['result'];
1281 if (result === '1-0') {
1282 $("#whiteclock").text("1");
1283 $("#blackclock").text("0");
1284 $("#whiteclock").removeClass("running-clock");
1285 $("#blackclock").removeClass("running-clock");
1288 if (result === '1/2-1/2') {
1289 $("#whiteclock").text("1/2");
1290 $("#blackclock").text("1/2");
1291 $("#whiteclock").removeClass("running-clock");
1292 $("#blackclock").removeClass("running-clock");
1295 if (result === '0-1') {
1296 $("#whiteclock").text("0");
1297 $("#blackclock").text("1");
1298 $("#whiteclock").removeClass("running-clock");
1299 $("#blackclock").removeClass("running-clock");
1304 var white_clock_ms = null;
1305 var black_clock_ms = null;
1306 var show_seconds = false;
1309 if (data['position'] &&
1310 data['position']['white_clock'] &&
1311 data['position']['black_clock']) {
1312 white_clock_ms = data['position']['white_clock'] * 1000;
1313 black_clock_ms = data['position']['black_clock'] * 1000;
1316 // Dynamic clock (only one, obviously).
1318 if (data['position']['white_clock_target']) {
1320 $("#whiteclock").addClass("running-clock");
1321 $("#blackclock").removeClass("running-clock");
1322 } else if (data['position']['black_clock_target']) {
1324 $("#whiteclock").removeClass("running-clock");
1325 $("#blackclock").addClass("running-clock");
1327 $("#whiteclock").removeClass("running-clock");
1328 $("#blackclock").removeClass("running-clock");
1332 var now = new Date().getTime() + client_clock_offset_ms;
1333 remaining_ms = data['position'][color + '_clock_target'] * 1000 - now;
1334 if (color === "white") {
1335 white_clock_ms = remaining_ms;
1337 black_clock_ms = remaining_ms;
1341 if (white_clock_ms === null || black_clock_ms === null) {
1342 $("#whiteclock").empty();
1343 $("#blackclock").empty();
1347 // If either player has ten minutes or less left, add the second counters.
1348 var show_seconds = (white_clock_ms < 60 * 10 * 1000 || black_clock_ms < 60 * 10 * 1000);
1351 // See when the clock will change next, and update right after that.
1354 next_update_ms = remaining_ms % 1000 + 100;
1356 next_update_ms = remaining_ms % 60000 + 100;
1358 clock_timer = setTimeout(update_clock, next_update_ms);
1361 $("#whiteclock").text(format_clock(white_clock_ms, show_seconds));
1362 $("#blackclock").text(format_clock(black_clock_ms, show_seconds));
1366 * @param {Number} remaining_ms
1367 * @param {boolean} show_seconds
1369 var format_clock = function(remaining_ms, show_seconds) {
1370 if (remaining_ms <= 0) {
1378 var remaining = Math.floor(remaining_ms / 1000);
1379 var seconds = remaining % 60;
1380 remaining = (remaining - seconds) / 60;
1381 var minutes = remaining % 60;
1382 remaining = (remaining - minutes) / 60;
1383 var hours = remaining;
1385 return format_2d(hours) + ":" + format_2d(minutes) + ":" + format_2d(seconds);
1387 return format_2d(hours) + ":" + format_2d(minutes);
1394 var format_2d = function(x) {
1403 * @param {string} move
1404 * @param {Number} move_num
1405 * @param {boolean} white_to_play
1407 var format_move_with_number = function(move, move_num, white_to_play) {
1409 if (white_to_play) {
1410 ret = (move_num - 1) + '… ';
1412 ret = move_num + '. ';
1419 * @param {string} move
1420 * @param {Number} halfmove_num
1422 var format_halfmove_with_number = function(move, halfmove_num) {
1423 return format_move_with_number(
1425 Math.floor(halfmove_num / 2) + 1,
1426 halfmove_num % 2 == 0);
1430 * @param {Object} data
1431 * @param {Number} halfmove_num
1433 var format_tooltip = function(data, halfmove_num) {
1434 if (data['score_history'][halfmove_num] ||
1435 halfmove_num === data['position']['pretty_history'].length) {
1438 if (halfmove_num === data['position']['pretty_history'].length) {
1439 move = data['position']['last_move'];
1440 short_score = format_short_score(data['score']);
1442 move = data['position']['pretty_history'][halfmove_num];
1443 short_score = format_short_score(data['score_history'][halfmove_num]);
1445 var move_with_number = format_halfmove_with_number(move, halfmove_num);
1447 return "After " + move_with_number + ": " + short_score;
1449 for (var i = halfmove_num; i --> 0; ) {
1450 if (data['score_history'][i]) {
1451 var move = data['position']['pretty_history'][i];
1452 return "[Analysis kept from " + format_halfmove_with_number(move, i) + "]";
1459 * @param {boolean} sort_by_score
1461 var resort_refutation_lines = function(sort_by_score) {
1462 sort_refutation_lines_by_score = sort_by_score;
1463 if (supports_html5_storage()) {
1464 localStorage['sort_refutation_lines_by_score'] = sort_by_score ? 1 : 0;
1466 update_refutation_lines();
1468 window['resort_refutation_lines'] = resort_refutation_lines;
1471 * @param {boolean} truncate_history
1473 var set_truncate_history = function(truncate_history) {
1474 truncate_display_history = truncate_history;
1475 update_refutation_lines();
1477 window['set_truncate_history'] = set_truncate_history;
1480 * @param {number} line_num
1481 * @param {number} move_num
1483 var show_line = function(line_num, move_num) {
1484 if (line_num == -1) {
1485 current_display_line = null;
1486 current_display_move = null;
1487 hash_refutation_lines = null;
1488 if (displayed_analysis_data) {
1489 // TODO: Support exiting to history position if we are in an
1490 // analysis line of a history position.
1491 displayed_analysis_data = null;
1496 current_display_line = jQuery.extend({}, display_lines[line_num]); // Shallow clone.
1497 current_display_move = move_num + current_display_line.start_display_move_num;
1499 current_display_line_is_history = (line_num == 0);
1501 update_historic_analysis();
1502 update_displayed_line();
1503 update_board_highlight();
1504 update_move_highlight();
1507 window['show_line'] = show_line;
1509 var prev_move = function() {
1510 if (current_display_line &&
1511 current_display_move >= current_display_line.start_display_move_num) {
1512 --current_display_move;
1514 update_historic_analysis();
1515 update_displayed_line();
1516 update_move_highlight();
1518 window['prev_move'] = prev_move;
1520 var next_move = function() {
1521 if (current_display_line &&
1522 current_display_move < current_display_line.pretty_pv.length - 1) {
1523 ++current_display_move;
1525 update_historic_analysis();
1526 update_displayed_line();
1527 update_move_highlight();
1529 window['next_move'] = next_move;
1531 var next_game = function() {
1532 if (current_games === null) {
1536 // Try to find the game we are currently looking at.
1537 for (var game_num = 0; game_num < current_games.length; ++game_num) {
1538 var game = current_games[game_num];
1539 if (game['url'] === backend_url) {
1540 var next_game_num = (game_num + 1) % current_games.length;
1541 switch_backend(current_games[next_game_num]['url'], current_games[next_game_num]['hashurl']);
1546 // Couldn't find it; give up.
1549 var update_historic_analysis = function() {
1550 if (!current_display_line_is_history) {
1553 if (current_display_move == current_display_line.pretty_pv.length - 1) {
1554 displayed_analysis_data = null;
1558 // Fetch old analysis for this line if it exists.
1559 var hiddenboard = chess_from(null, current_display_line.pretty_pv, current_display_move);
1560 var filename = "/history/move" + (current_display_move + 1) + "-" +
1561 hiddenboard.fen().replace(/ /g, '_').replace(/\//g, '-') + ".json";
1563 current_historic_xhr = $.ajax({
1565 }).done(function(data, textstatus, xhr) {
1566 displayed_analysis_data = data;
1568 }).fail(function(jqXHR, textStatus, errorThrown) {
1569 if (textStatus === "abort") {
1570 // Aborted because we are switching backends. Don't do anything;
1571 // we will already have been cleared.
1573 displayed_analysis_data = {'failed': true};
1580 * @param {string} fen
1582 var update_imbalance = function(fen) {
1583 var hiddenboard = new Chess(fen);
1584 var imbalance = {'k': 0, 'q': 0, 'r': 0, 'b': 0, 'n': 0, 'p': 0};
1585 for (var row = 0; row < 8; ++row) {
1586 for (var col = 0; col < 8; ++col) {
1587 var col_text = String.fromCharCode('a1'.charCodeAt(0) + col);
1588 var row_text = String.fromCharCode('a1'.charCodeAt(1) + row);
1589 var square = col_text + row_text;
1590 var contents = hiddenboard.get(square);
1591 if (contents !== null) {
1592 if (contents.color === 'w') {
1593 ++imbalance[contents.type];
1595 --imbalance[contents.type];
1600 var white_imbalance = '';
1601 var black_imbalance = '';
1602 for (var piece in imbalance) {
1603 for (var i = 0; i < imbalance[piece]; ++i) {
1604 white_imbalance += '<img src="img/chesspieces/wikipedia/w' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1606 for (var i = 0; i < -imbalance[piece]; ++i) {
1607 black_imbalance += '<img src="img/chesspieces/wikipedia/b' + piece.toUpperCase() + '.png" alt="" style="width: 15px;height: 15px;">';
1610 $('#whiteimbalance').html(white_imbalance);
1611 $('#blackimbalance').html(black_imbalance);
1614 /** Mark the currently selected move in red.
1615 * Also replaces the PV with the current displayed line if it's not shown
1616 * anywhere else on the screen.
1618 var update_move_highlight = function() {
1619 if (highlighted_move !== null) {
1620 highlighted_move.removeClass('highlight');
1622 if (current_display_line) {
1623 var display_line_num = find_display_line_matching_num();
1624 if (display_line_num === null) {
1625 // Replace the PV with the (complete) line.
1626 $("#pvtitle").text("Exploring:");
1627 current_display_line.start_display_move_num = 0;
1628 display_lines.push(current_display_line);
1629 $("#pv").html(print_pv(display_lines.length - 1));
1630 display_line_num = display_lines.length - 1;
1633 highlighted_move = $("#automove" + display_line_num + "-" + (current_display_move - current_display_line.start_display_move_num));
1634 highlighted_move.addClass('highlight');
1639 * See if the current displayed line is identical to any of the ones
1640 * we have on screen. (It might not be if e.g. the analysis reloaded
1641 * since we started looking.)
1645 var find_display_line_matching_num = function() {
1646 for (var i = 0; i < display_lines.length; ++i) {
1647 var line = display_lines[i];
1648 if (line.start_display_move_num > 0) continue;
1649 if (current_display_line.start_fen !== line.start_fen) continue;
1650 if (current_display_line.pretty_pv.length !== line.pretty_pv.length) continue;
1652 for (var j = 0; j < line.pretty_pv.length; ++j) {
1653 if (current_display_line.pretty_pv[j] !== line.pretty_pv[j]) {
1665 var update_displayed_line = function() {
1666 if (current_display_line === null) {
1667 $("#linenav").hide();
1668 $("#linemsg").show();
1669 display_fen = base_fen;
1670 board.position(base_fen);
1671 update_imbalance(base_fen);
1675 $("#linenav").show();
1676 $("#linemsg").hide();
1678 if (current_display_move <= 0) {
1679 $("#prevmove").html("Previous");
1681 $("#prevmove").html("<a href=\"javascript:prev_move();\">Previous</a></span>");
1683 if (current_display_move == current_display_line.pretty_pv.length - 1) {
1684 $("#nextmove").html("Next");
1686 $("#nextmove").html("<a href=\"javascript:next_move();\">Next</a></span>");
1689 var hiddenboard = chess_from(current_display_line.start_fen, current_display_line.pretty_pv, current_display_move);
1690 display_fen = hiddenboard.fen();
1691 board_is_animating = true;
1692 var old_fen = board.fen();
1693 board.position(hiddenboard.fen());
1694 if (board.fen() === old_fen) {
1695 board_is_animating = false;
1696 } else if (!current_display_line_is_history) {
1697 // Fire off a hash request, since we're now off the main position
1698 // and it just changed.
1699 explore_hash(display_fen);
1701 update_imbalance(hiddenboard.fen());
1705 * @param {boolean} param_enable_sound
1707 var set_sound = function(param_enable_sound) {
1708 enable_sound = param_enable_sound;
1710 $("#soundon").html("<strong>On</strong>");
1711 $("#soundoff").html("<a href=\"javascript:set_sound(false)\">Off</a>");
1713 // Seemingly at least Firefox prefers MP3 over Opus; tell it otherwise,
1714 // and also preload the file since the user has selected audio.
1715 var ding = document.getElementById('ding');
1716 if (ding && ding.canPlayType && ding.canPlayType('audio/ogg; codecs="opus"') === 'probably') {
1717 ding.src = 'ding.opus';
1721 $("#soundon").html("<a href=\"javascript:set_sound(true)\">On</a>");
1722 $("#soundoff").html("<strong>Off</strong>");
1724 if (supports_html5_storage()) {
1725 localStorage['enable_sound'] = enable_sound ? 1 : 0;
1728 window['set_sound'] = set_sound;
1730 /** Send off a hash probe request to the backend.
1731 * @param {string} fen
1733 var explore_hash = function(fen) {
1734 // If we already have a backend response going, abort it.
1735 if (current_hash_xhr) {
1736 current_hash_xhr.abort();
1738 if (current_hash_display_timer) {
1739 clearTimeout(current_hash_display_timer);
1740 current_hash_display_timer = null;
1742 $("#refutationlines").empty();
1743 current_hash_xhr = $.ajax({
1744 url: backend_hash_url + "?fen=" + fen
1745 }).done(function(data, textstatus, xhr) {
1746 show_explore_hash_results(data, fen);
1750 /** Process the JSON response from a hash probe request.
1751 * @param {!Object} data
1752 * @param {string} fen
1754 var show_explore_hash_results = function(data, fen) {
1755 if (board_is_animating) {
1756 // Updating while the animation is still going causes
1757 // the animation to jerk. This is pretty crude, but it will do.
1758 current_hash_display_timer = setTimeout(function() { show_explore_hash_results(data, fen); }, 100);
1761 current_hash_display_timer = null;
1762 hash_refutation_lines = data['lines'];
1766 // almost all of this stuff comes from the chessboard.js example page
1767 var onDragStart = function(source, piece, position, orientation) {
1768 var pseudogame = new Chess(display_fen);
1769 if (pseudogame.game_over() === true ||
1770 (pseudogame.turn() === 'w' && piece.search(/^b/) !== -1) ||
1771 (pseudogame.turn() === 'b' && piece.search(/^w/) !== -1)) {
1775 recommended_move = get_best_move(pseudogame, source, null, pseudogame.turn() === 'b');
1776 if (recommended_move) {
1777 var squareEl = $('#board .square-' + recommended_move.to);
1778 squareEl.addClass('highlight1-32417');
1783 var mousedownSquare = function(e) {
1784 reverse_dragging_from = null;
1785 var square = $(this).attr('data-square');
1787 var pseudogame = new Chess(display_fen);
1788 if (pseudogame.game_over() === true) {
1792 // If the square is empty, or has a piece of the side not to move,
1793 // we handle it. If not, normal piece dragging will take it.
1794 var position = board.position();
1795 if (!position.hasOwnProperty(square) ||
1796 (pseudogame.turn() === 'w' && position[square].search(/^b/) !== -1) ||
1797 (pseudogame.turn() === 'b' && position[square].search(/^w/) !== -1)) {
1798 reverse_dragging_from = square;
1799 recommended_move = get_best_move(pseudogame, null, square, pseudogame.turn() === 'b');
1800 if (recommended_move) {
1801 var squareEl = $('#board .square-' + recommended_move.from);
1802 squareEl.addClass('highlight1-32417');
1803 squareEl = $('#board .square-' + recommended_move.to);
1804 squareEl.addClass('highlight1-32417');
1809 var mouseupSquare = function(e) {
1810 if (reverse_dragging_from === null) {
1813 var source = $(this).attr('data-square');
1814 var target = reverse_dragging_from;
1815 reverse_dragging_from = null;
1816 if (onDrop(source, target) !== 'snapback') {
1817 onSnapEnd(source, target);
1819 $("#board").find('.square-55d63').removeClass('highlight1-32417');
1822 var get_best_move = function(game, source, target, invert) {
1823 var moves = game.moves({ verbose: true });
1824 if (source !== null) {
1825 moves = moves.filter(function(move) { return move.from == source; });
1827 if (target !== null) {
1828 moves = moves.filter(function(move) { return move.to == target; });
1830 if (moves.length == 0) {
1833 if (moves.length == 1) {
1837 // More than one move. Use the display lines (if we have them)
1838 // to disambiguate; otherwise, we have no information.
1840 for (var i = 0; i < moves.length; ++i) {
1841 move_hash[moves[i].san] = moves[i];
1844 // See if we're already exploring some line.
1845 if (current_display_line &&
1846 current_display_move < current_display_line.pretty_pv.length - 1) {
1847 var first_move = current_display_line.pretty_pv[current_display_move + 1];
1848 if (move_hash[first_move]) {
1849 return move_hash[first_move];
1853 // History and PV take priority over the display lines.
1854 for (var i = 0; i < 2; ++i) {
1855 var line = display_lines[i];
1856 var first_move = line.pretty_pv[line.start_display_move_num];
1857 if (move_hash[first_move]) {
1858 return move_hash[first_move];
1862 var best_move = null;
1863 var best_move_score = null;
1865 for (var move in refutation_lines) {
1866 var line = refutation_lines[move];
1867 if (!line['score']) {
1870 var first_move = line['pv_pretty'][0];
1871 if (move_hash[first_move]) {
1872 var score = compute_score_sort_key(line['score'], invert);
1873 if (best_move_score === null || score > best_move_score) {
1874 best_move = move_hash[first_move];
1875 best_move_score = score;
1882 var onDrop = function(source, target) {
1883 if (source === target) {
1884 if (recommended_move === null) {
1887 // Accept the move. It will be changed in onSnapEnd.
1891 // Suggestion not asked for.
1892 recommended_move = null;
1895 // see if the move is legal
1896 var pseudogame = new Chess(display_fen);
1897 var move = pseudogame.move({
1900 promotion: 'q' // NOTE: always promote to a queen for example simplicity
1904 if (move === null) return 'snapback';
1907 var onSnapEnd = function(source, target) {
1908 if (source === target && recommended_move !== null) {
1909 source = recommended_move.from;
1910 target = recommended_move.to;
1912 recommended_move = null;
1913 var pseudogame = new Chess(display_fen);
1914 var move = pseudogame.move({
1917 promotion: 'q' // NOTE: always promote to a queen for example simplicity
1920 if (current_display_line &&
1921 current_display_move < current_display_line.pretty_pv.length - 1 &&
1922 current_display_line.pretty_pv[current_display_move + 1] === move.san) {
1927 // Walk down the displayed lines until we find one that starts with
1928 // this move, then select that. Note that this gives us a good priority
1929 // order (history first, then PV, then multi-PV lines).
1930 for (var i = 0; i < display_lines.length; ++i) {
1931 var line = display_lines[i];
1932 if (line.pretty_pv[line.start_display_move_num] === move.san) {
1938 // Shouldn't really be here if we have hash probes, but there's really
1939 // nothing we can do.
1941 // End of dragging-related code.
1943 var fmt_cp = function(v) {
1947 return "+" + (v / 100).toFixed(2);
1950 return "-" + (v / 100).toFixed(2);
1954 var format_short_score = function(score) {
1958 if (score[0] === 'm') {
1959 if (score[2]) { // Is a bound.
1960 return score[2] + "\u00a0M " + score[1];
1962 return "M " + score[1];
1964 } else if (score[0] === 'd') {
1966 } else if (score[0] === 'cp') {
1967 if (score[2]) { // Is a bound.
1968 return score[2] + "\u00a0" + fmt_cp(score[1]);
1970 return fmt_cp(score[1]);
1976 var format_long_score = function(score) {
1977 if (score[0] === 'm') {
1979 return "White mates in " + score[1];
1981 return "Black mates in " + (-score[1]);
1983 } else if (score[0] === 'd') {
1984 return "Theoretical draw";
1985 } else if (score[0] === 'cp') {
1986 return "Score: " + format_short_score(score);
1991 var compute_plot_score = function(score) {
1992 if (score[0] === 'm') {
1998 } else if (score[0] === 'd') {
2000 } else if (score[0] === 'cp') {
2001 if (score[1] > 500) {
2003 } else if (score[1] < -500) {
2013 * @param score The score digest tuple.
2014 * @param {boolean} invert Whether black is to play.
2017 var compute_score_sort_key = function(score, invert) {
2022 if (score[0] === 'm') {
2025 s = 99999 - score[1];
2027 // Black mates (note the double negative for score[1]).
2028 s = -99999 - score[1];
2032 } else if (score[0] === 'd') {
2034 } else if (score[0] === 'cp') {
2035 return invert ? -score[1] : score[1];
2041 * @param {string} new_backend_url
2043 var switch_backend = function(new_backend_url, new_backend_hash_url) {
2044 // Stop looking at historic data.
2045 current_display_line = null;
2046 current_display_move = null;
2047 displayed_analysis_data = null;
2048 if (current_historic_xhr) {
2049 current_historic_xhr.abort();
2052 // If we already have a backend response going, abort it.
2053 if (current_analysis_xhr) {
2054 current_analysis_xhr.abort();
2056 if (current_hash_xhr) {
2057 current_hash_xhr.abort();
2060 // Otherwise, we should have a timer going to start a new one.
2062 if (current_analysis_request_timer) {
2063 clearTimeout(current_analysis_request_timer);
2064 current_analysis_request_timer = null;
2066 if (current_hash_display_timer) {
2067 clearTimeout(current_hash_display_timer);
2068 current_hash_display_timer = null;
2071 // Request an immediate fetch with the new backend.
2072 backend_url = new_backend_url;
2073 backend_hash_url = new_backend_hash_url;
2074 current_analysis_data = null;
2078 window['switch_backend'] = switch_backend;
2080 var init = function() {
2081 unique = get_unique();
2083 // Load settings from HTML5 local storage if available.
2084 if (supports_html5_storage() && localStorage['enable_sound']) {
2085 set_sound(parseInt(localStorage['enable_sound']));
2089 if (supports_html5_storage() && localStorage['sort_refutation_lines_by_score']) {
2090 sort_refutation_lines_by_score = parseInt(localStorage['sort_refutation_lines_by_score']);
2092 sort_refutation_lines_by_score = true;
2096 board = new window.ChessBoard('board', {
2097 onMoveEnd: function() { board_is_animating = false; },
2100 onDragStart: onDragStart,
2102 onSnapEnd: onSnapEnd
2104 $("#board").on('mousedown', '.square-55d63', mousedownSquare);
2105 $("#board").on('mouseup', '.square-55d63', mouseupSquare);
2108 $(window).resize(function() {
2110 update_sparkline(displayed_analysis_data || current_analysis_data);
2111 update_board_highlight();
2114 $(window).keyup(function(event) {
2115 if (event.which == 39) { // Left arrow.
2117 } else if (event.which == 37) { // Right arrow.
2119 } else if (event.which >= 49 && event.which <= 57) { // 1-9.
2120 var num = event.which - 49;
2121 if (current_games && current_games.length >= num) {
2122 switch_backend(current_games[num]['url'], current_games[num]['hashurl']);
2124 } else if (event.which == 78) { // N.
2128 window.addEventListener('hashchange', possibly_switch_game_from_hash, false);
2130 $(document).ready(init);