3 /** @type {window.ChessBoard} @private */
7 * The most recent analysis data we have from the server
8 * (about the most recent position).
12 var current_analysis_data = null;
15 * If we are displaying previous analysis, this is non-null,
16 * and will override most of current_analysis_data.
21 var displayed_analysis_data = null;
36 /** @type {Array.<Array.<boolean>>} */
37 var occupied_by_arrows = [];
39 var refutation_lines = [];
41 /** @type {!number} @private */
44 /** @type {!string} @private */
47 /** @type {number} @private */
50 /** @type {boolean} @private */
51 var sort_refutation_lines_by_score = true;
53 /** @type {boolean} @private */
54 var truncate_display_history = true;
56 /** @type {!string|undefined} @private */
57 var highlight_from = undefined;
59 /** @type {!string|undefined} @private */
60 var highlight_to = undefined;
62 /** @type {?jQuery} @private */
63 var highlighted_move = null;
65 /** @type {?number} @private */
68 /** The current position on the board, represented as a FEN string.
76 * uci_pv: Array.<string>,
77 * pretty_pv: Array.<string>,
82 /** @type {Array.<DisplayLine>}
85 var display_lines = [];
87 /** @type {?DisplayLine} @private */
88 var current_display_line = null;
90 /** @type {boolean} @private */
91 var current_display_line_is_history = false;
93 /** @type {?number} @private */
94 var current_display_move = null;
96 var supports_html5_storage = function() {
98 return 'localStorage' in window && window['localStorage'] !== null;
104 // Make the unique token persistent so people refreshing the page won't count twice.
105 // Of course, you can never fully protect against people deliberately wanting to spam.
106 var get_unique = function() {
107 var use_local_storage = supports_html5_storage();
108 if (use_local_storage && localStorage['unique']) {
109 return localStorage['unique'];
111 var unique = Math.random();
112 if (use_local_storage) {
113 localStorage['unique'] = unique;
118 var request_update = function() {
120 url: "/analysis.pl?ims=" + ims + "&unique=" + unique
121 }).done(function(data, textstatus, xhr) {
122 ims = xhr.getResponseHeader('X-Remoteglot-Last-Modified');
123 var num_viewers = xhr.getResponseHeader('X-Remoteglot-Num-Viewers');
124 current_analysis_data = data;
125 update_board(current_analysis_data, displayed_analysis_data);
126 update_num_viewers(num_viewers);
129 setTimeout(function() { request_update(); }, 100);
131 // Wait ten seconds, then try again.
132 setTimeout(function() { request_update(); }, 10000);
136 var clear_arrows = function() {
137 for (var i = 0; i < arrows.length; ++i) {
139 arrows[i].svg.parentElement.removeChild(arrows[i].svg);
140 delete arrows[i].svg;
145 occupied_by_arrows = [];
146 for (var y = 0; y < 8; ++y) {
147 occupied_by_arrows.push([false, false, false, false, false, false, false, false]);
151 var redraw_arrows = function() {
152 for (var i = 0; i < arrows.length; ++i) {
153 position_arrow(arrows[i]);
157 /** @param {!number} x
160 var sign = function(x) {
170 /** See if drawing this arrow on the board would cause unduly amount of confusion.
171 * @param {!string} from The square the arrow is from (e.g. e4).
172 * @param {!string} to The square the arrow is to (e.g. e4).
175 var interfering_arrow = function(from, to) {
176 var from_col = from.charCodeAt(0) - "a1".charCodeAt(0);
177 var from_row = from.charCodeAt(1) - "a1".charCodeAt(1);
178 var to_col = to.charCodeAt(0) - "a1".charCodeAt(0);
179 var to_row = to.charCodeAt(1) - "a1".charCodeAt(1);
181 occupied_by_arrows[from_row][from_col] = true;
183 // Knight move: Just check that we haven't been at the destination before.
184 if ((Math.abs(to_col - from_col) == 2 && Math.abs(to_row - from_row) == 1) ||
185 (Math.abs(to_col - from_col) == 1 && Math.abs(to_row - from_row) == 2)) {
186 return occupied_by_arrows[to_row][to_col];
189 // Sliding piece: Check if anything except the from-square is seen before.
190 var dx = sign(to_col - from_col);
191 var dy = sign(to_row - from_row);
197 if (occupied_by_arrows[y][x]) {
200 occupied_by_arrows[y][x] = true;
201 } while (x != to_col || y != to_row);
206 /** Find a point along the coordinate system given by the given line,
207 * <t> units forward from the start of the line, <u> units to the right of it.
208 * @param {!number} x1
209 * @param {!number} x2
210 * @param {!number} y1
211 * @param {!number} y2
214 * @return {!string} The point in "x y" form, suitable for SVG paths.
216 var point_from_start = function(x1, y1, x2, y2, t, u) {
220 var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
224 var x = x1 + dx * t + dy * u;
225 var y = y1 + dy * t - dx * u;
229 /** Find a point along the coordinate system given by the given line,
230 * <t> units forward from the end of the line, <u> units to the right of it.
231 * @param {!number} x1
232 * @param {!number} x2
233 * @param {!number} y1
234 * @param {!number} y2
237 * @return {!string} The point in "x y" form, suitable for SVG paths.
239 var point_from_end = function(x1, y1, x2, y2, t, u) {
243 var norm = 1.0 / Math.sqrt(dx * dx + dy * dy);
247 var x = x2 + dx * t + dy * u;
248 var y = y2 + dy * t - dx * u;
252 var position_arrow = function(arrow) {
254 arrow.svg.parentElement.removeChild(arrow.svg);
257 if (current_display_line !== null) {
261 var pos = $(".square-a8").position();
263 var zoom_factor = $("#board").width() / 400.0;
264 var line_width = arrow.line_width * zoom_factor;
265 var arrow_size = arrow.arrow_size * zoom_factor;
267 var square_width = $(".square-a8").width();
268 var from_y = (7 - arrow.from_row + 0.5)*square_width;
269 var to_y = (7 - arrow.to_row + 0.5)*square_width;
270 var from_x = (arrow.from_col + 0.5)*square_width;
271 var to_x = (arrow.to_col + 0.5)*square_width;
273 var SVG_NS = "http://www.w3.org/2000/svg";
274 var XHTML_NS = "http://www.w3.org/1999/xhtml";
275 var svg = document.createElementNS(SVG_NS, "svg");
276 svg.setAttribute("width", /** @type{number} */ ($("#board").width()));
277 svg.setAttribute("height", /** @type{number} */ ($("#board").height()));
278 svg.setAttribute("style", "position: absolute");
279 svg.setAttribute("position", "absolute");
280 svg.setAttribute("version", "1.1");
281 svg.setAttribute("class", "c1");
282 svg.setAttribute("xmlns", XHTML_NS);
290 var outline = document.createElementNS(SVG_NS, "path");
291 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));
292 outline.setAttribute("xmlns", XHTML_NS);
293 outline.setAttribute("stroke", "#666");
294 outline.setAttribute("stroke-width", line_width + 2);
295 outline.setAttribute("fill", "none");
296 svg.appendChild(outline);
298 var path = document.createElementNS(SVG_NS, "path");
299 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));
300 path.setAttribute("xmlns", XHTML_NS);
301 path.setAttribute("stroke", arrow.fg_color);
302 path.setAttribute("stroke-width", line_width);
303 path.setAttribute("fill", "none");
304 svg.appendChild(path);
306 // Then the arrow head.
307 var head = document.createElementNS(SVG_NS, "path");
308 head.setAttribute("d",
309 "M " + point_from_end(x1, y1, x2, y2, 0, 0) +
310 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, -arrow_size / 2) +
311 " L " + point_from_end(x1, y1, x2, y2, -arrow_size * .623, 0.0) +
312 " L " + point_from_end(x1, y1, x2, y2, -arrow_size, arrow_size / 2) +
313 " L " + point_from_end(x1, y1, x2, y2, 0, 0));
314 head.setAttribute("xmlns", XHTML_NS);
315 head.setAttribute("stroke", "#000");
316 head.setAttribute("stroke-width", "1");
317 head.setAttribute("fill", arrow.fg_color);
318 svg.appendChild(head);
320 $(svg).css({ top: pos.top, left: pos.left });
321 document.body.appendChild(svg);
326 * @param {!string} from_square
327 * @param {!string} to_square
328 * @param {!string} fg_color
329 * @param {number} line_width
330 * @param {number} arrow_size
332 var create_arrow = function(from_square, to_square, fg_color, line_width, arrow_size) {
333 var from_col = from_square.charCodeAt(0) - "a1".charCodeAt(0);
334 var from_row = from_square.charCodeAt(1) - "a1".charCodeAt(1);
335 var to_col = to_square.charCodeAt(0) - "a1".charCodeAt(0);
336 var to_row = to_square.charCodeAt(1) - "a1".charCodeAt(1);
344 line_width: line_width,
345 arrow_size: arrow_size,
349 position_arrow(arrow);
353 var compare_by_sort_key = function(refutation_lines, a, b) {
354 var ska = refutation_lines[a]['sort_key'];
355 var skb = refutation_lines[b]['sort_key'];
356 if (ska < skb) return -1;
357 if (ska > skb) return 1;
361 var compare_by_score = function(refutation_lines, a, b) {
362 var sa = parseInt(refutation_lines[b]['score_sort_key'], 10);
363 var sb = parseInt(refutation_lines[a]['score_sort_key'], 10);
368 * Fake multi-PV using the refutation lines. Find all “relevant” moves,
369 * sorted by quality, descending.
371 * @param {!Object} data
372 * @param {number} margin The maximum number of centipawns worse than the
373 * best move can be and still be included.
374 * @return {Array.<string>} The UCI representation (e.g. e1g1) of all
375 * moves, in score order.
377 var find_nonstupid_moves = function(data, margin) {
378 // First of all, if there are any moves that are more than 0.5 ahead of
379 // the primary move, the refutation lines are probably bunk, so just
381 var best_score = undefined;
382 var pv_score = undefined;
383 for (var move in data['refutation_lines']) {
384 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
385 if (move == data['pv_uci'][0]) {
388 if (best_score === undefined || score > best_score) {
391 if (!(data['refutation_lines'][move]['depth'] >= 8)) {
396 if (best_score - pv_score > 50) {
400 // Now find all moves that are within “margin” of the best score.
401 // The PV move will always be first.
403 for (var move in data['refutation_lines']) {
404 var score = parseInt(data['refutation_lines'][move]['score_sort_key'], 10);
405 if (move != data['pv_uci'][0] && best_score - score <= margin) {
409 moves = moves.sort(function(a, b) { return compare_by_score(data['refutation_lines'], a, b) });
410 moves.unshift(data['pv_uci'][0]);
419 var thousands = function(x) {
420 return String(x).split('').reverse().join('').replace(/(\d{3}\B)/g, '$1,').split('').reverse().join('');
424 * @param {!string} fen
425 * @param {Array.<string>} uci_pv
426 * @param {number} move_num
427 * @param {!string} toplay
428 * @param {number=} opt_limit
429 * @param {boolean=} opt_showlast
431 var add_pv = function(fen, uci_pv, move_num, toplay, opt_limit, opt_showlast) {
432 var hiddenboard = new Chess();
433 hiddenboard.load(fen);
434 for (var i = 0; i < uci_pv.length; ++i) {
435 hiddenboard.move(ucimove_to_chessjs_move(uci_pv[i]));
437 var pretty_pv = hiddenboard.history();
442 pretty_pv: pretty_pv,
443 line_number: display_lines.length
445 return print_pv(display_lines.length - 1, pretty_pv, move_num, toplay, opt_limit, opt_showlast);
449 * @param {number} line_num
450 * @param {Array.<string>} pretty_pv
451 * @param {number} move_num
452 * @param {!string} toplay
453 * @param {number=} opt_limit
454 * @param {boolean=} opt_showlast
456 var print_pv = function(line_num, pretty_pv, move_num, toplay, opt_limit, opt_showlast) {
459 if (opt_limit && opt_showlast && pretty_pv.length > opt_limit) {
460 // Truncate the PV at the beginning (instead of at the end).
461 // We assume here that toplay is 'W'. We also assume that if
462 // opt_showlast is set, then it is the history, and thus,
463 // the UI should be to expand the history.
464 pv = '(<a class="move" href="javascript:collapse_history(false)">…</a>) ';
465 i = pretty_pv.length - opt_limit;
470 } else if (toplay == 'B' && pretty_pv.length > 0) {
471 var move = "<a class=\"move\" id=\"automove" + line_num + "-0\" href=\"javascript:show_line(" + line_num + ", " + 0 + ");\">" + pretty_pv[0] + "</a>";
472 pv = move_num + '. … ' + move;
477 for ( ; i < pretty_pv.length; ++i) {
478 var move = "<a class=\"move\" id=\"automove" + line_num + "-" + i + "\" href=\"javascript:show_line(" + line_num + ", " + i + ");\">" + pretty_pv[i] + "</a>";
481 if (i > opt_limit && !opt_showlast) {
487 pv += move_num + '. ' + move;
498 var update_highlight = function() {
499 $("#board").find('.square-55d63').removeClass('nonuglyhighlight');
500 if (current_display_line === null && highlight_from !== undefined && highlight_to !== undefined) {
501 $("#board").find('.square-' + highlight_from).addClass('nonuglyhighlight');
502 $("#board").find('.square-' + highlight_to).addClass('nonuglyhighlight');
506 var update_history = function() {
507 if (display_lines[0] === null || display_lines[0].pretty_pv.length == 0) {
508 $("#history").html("No history");
509 } else if (truncate_display_history) {
510 $("#history").html(print_pv(0, display_lines[0].pretty_pv, 1, 'W', 8, true));
513 '(<a class="move" href="javascript:collapse_history(true)">collapse</a>) ' +
514 print_pv(0, display_lines[0].pretty_pv, 1, 'W'));
519 * @param {!boolean} truncate_history
521 var collapse_history = function(truncate_history) {
522 truncate_display_history = truncate_history;
525 window['collapse_history'] = collapse_history;
527 var update_refutation_lines = function() {
531 if (display_lines.length > 2) {
532 display_lines = [ display_lines[0], display_lines[1] ];
535 var tbl = $("#refutationlines");
539 for (var move in refutation_lines) {
542 var compare = sort_refutation_lines_by_score ? compare_by_score : compare_by_sort_key;
543 moves = moves.sort(function(a, b) { return compare(refutation_lines, a, b) });
544 for (var i = 0; i < moves.length; ++i) {
545 var line = refutation_lines[moves[i]];
547 var tr = document.createElement("tr");
549 var move_td = document.createElement("td");
550 tr.appendChild(move_td);
551 $(move_td).addClass("move");
552 if (line['pv_uci'].length == 0) {
553 $(move_td).text(line['pretty_move']);
555 var move = "<a class=\"move\" href=\"javascript:show_line(" + display_lines.length + ", " + 0 + ");\">" + line['pretty_move'] + "</a>";
556 $(move_td).html(move);
559 var score_td = document.createElement("td");
560 tr.appendChild(score_td);
561 $(score_td).addClass("score");
562 $(score_td).text(line['pretty_score']);
564 var depth_td = document.createElement("td");
565 tr.appendChild(depth_td);
566 $(depth_td).addClass("depth");
567 $(depth_td).text("d" + line['depth']);
569 var pv_td = document.createElement("td");
570 tr.appendChild(pv_td);
571 $(pv_td).addClass("pv");
572 $(pv_td).html(add_pv(fen, line['pv_uci'], move_num, toplay, 10));
577 // Make one of the links clickable and the other nonclickable.
578 if (sort_refutation_lines_by_score) {
579 $("#sortbyscore0").html("<a href=\"javascript:resort_refutation_lines(false)\">Move</a>");
580 $("#sortbyscore1").html("<strong>Score</strong>");
582 $("#sortbyscore0").html("<strong>Move</strong>");
583 $("#sortbyscore1").html("<a href=\"javascript:resort_refutation_lines(true)\">Score</a>");
588 * @param {Object} data
589 * @param {?Object} display_data
591 var update_board = function(current_data, display_data) {
592 var data = display_data || current_data;
596 // Print the history. This is pretty much the only thing that's
597 // unconditionally taken from current_data (we're not interested in
598 // historic history).
599 if (current_data['position']['history']) {
600 add_pv('start', current_data['position']['history'], 1, 'W', 8, true);
602 display_lines.push(null);
606 // The headline. Names are always fetched from current_data;
607 // the rest can depend a bit.
610 current_data['position']['player_w'] && current_data['position']['player_b']) {
611 headline = current_data['position']['player_w'] + '–' +
612 current_data['position']['player_b'] + ', analysis';
614 headline = 'Analysis';
619 // Displaying some non-current position, pick out the last move
620 // from the history. This will work even if the fetch failed.
621 last_move = format_move_with_number(
622 current_display_line.pretty_pv[current_display_move],
623 Math.floor((current_display_move + 1) / 2) + 1,
624 (current_display_move % 2 == 1));
625 headline += ' after ' + last_move;
626 } else if (data['position']['last_move'] !== 'none') {
627 last_move = format_move_with_number(
628 data['position']['last_move'],
629 data['position']['move_num'],
630 data['position']['toplay'] == 'W');
631 headline += ' after ' + last_move;
635 $("#headline").text(headline);
637 // The <title> contains a very brief headline.
638 var title_elems = [];
639 if (data['short_score'] !== undefined && data['short_score'] !== null) {
640 title_elems.push(data['short_score']);
642 if (last_move !== null) {
643 title_elems.push(last_move);
646 if (title_elems.length != 0) {
647 document.title = '(' + title_elems.join(', ') + ') analysis.sesse.net';
649 document.title = 'analysis.sesse.net';
652 if (data['failed']) {
653 $("#score").text("No analysis for this move");
655 $("#searchstats").html(" ");
656 $("#refutationlines").empty();
657 refutation_lines = [];
658 update_refutation_lines();
663 if (data['id'] && data['id']['name'] !== null) {
664 $("#engineid").text(data['id']['name']);
668 if (data['score'] !== null) {
669 $("#score").text(data['score']);
673 if (data['tablebase'] == 1) {
674 $("#searchstats").text("Tablebase result");
675 } else if (data['nodes'] && data['nps'] && data['depth']) {
676 var stats = thousands(data['nodes']) + ' nodes, ' + thousands(data['nps']) + ' nodes/sec, depth ' + data['depth'] + ' ply';
677 if (data['seldepth']) {
678 stats += ' (' + data['seldepth'] + ' selective)';
680 if (data['tbhits'] && data['tbhits'] > 0) {
681 if (data['tbhits'] == 1) {
682 stats += ', one Syzygy hit';
684 stats += ', ' + thousands(data['tbhits']) + ' Syzygy hits';
688 $("#searchstats").text(stats);
690 $("#searchstats").text("");
693 // Update the board itself.
694 fen = data['position']['fen'];
695 update_displayed_line();
697 if (data['position']['last_move_uci']) {
698 highlight_from = data['position']['last_move_uci'].substr(0, 2);
699 highlight_to = data['position']['last_move_uci'].substr(2, 2);
701 highlight_from = highlight_to = undefined;
706 $("#pv").html(add_pv(data['position']['fen'], data['pv_uci'], data['position']['move_num'], data['position']['toplay']));
708 // Update the PV arrow.
710 if (data['pv_uci'].length >= 1) {
711 // draw a continuation arrow as long as it's the same piece
712 for (var i = 0; i < data['pv_uci'].length; i += 2) {
713 var from = data['pv_uci'][i].substr(0, 2);
714 var to = data['pv_uci'][i].substr(2,4);
715 if ((i >= 2 && from != data['pv_uci'][i - 2].substr(2, 2)) ||
716 interfering_arrow(from, to)) {
719 create_arrow(from, to, '#f66', 6, 20);
722 var alt_moves = find_nonstupid_moves(data, 30);
723 for (var i = 1; i < alt_moves.length && i < 3; ++i) {
724 create_arrow(alt_moves[i].substr(0, 2),
725 alt_moves[i].substr(2, 2), '#f66', 1, 10);
729 // See if all semi-reasonable moves have only one possible response.
730 if (data['pv_uci'].length >= 2) {
731 var nonstupid_moves = find_nonstupid_moves(data, 300);
732 var response = data['pv_uci'][1];
733 for (var i = 0; i < nonstupid_moves.length; ++i) {
734 if (nonstupid_moves[i] == data['pv_uci'][0]) {
735 // ignore the PV move for refutation lines.
738 if (!data['refutation_lines'] ||
739 !data['refutation_lines'][nonstupid_moves[i]] ||
740 !data['refutation_lines'][nonstupid_moves[i]]['pv_uci'] ||
741 data['refutation_lines'][nonstupid_moves[i]]['pv_uci'].length < 1) {
742 // Incomplete PV, abort.
743 response = undefined;
746 var this_response = data['refutation_lines'][nonstupid_moves[i]]['pv_uci'][1];
747 if (response !== this_response) {
748 // Different response depending on lines, abort.
749 response = undefined;
754 if (nonstupid_moves.length > 0 && response !== undefined) {
755 create_arrow(response.substr(0, 2),
756 response.substr(2, 2), '#66f', 6, 20);
760 // Update the refutation lines.
761 fen = data['position']['fen'];
762 move_num = data['position']['move_num'];
763 toplay = data['position']['toplay'];
764 refutation_lines = data['refutation_lines'];
765 update_refutation_lines();
769 * @param {number} num_viewers
771 var update_num_viewers = function(num_viewers) {
772 if (num_viewers === null) {
773 $("#numviewers").text("");
774 } else if (num_viewers == 1) {
775 $("#numviewers").text("You are the only current viewer");
777 $("#numviewers").text(num_viewers + " current viewers");
782 * @param {string} move
783 * @param {Number} move_num
784 * @param {boolean} white_to_play
786 var format_move_with_number = function(move, move_num, white_to_play) {
789 ret = (move_num - 1) + '… ';
791 ret = move_num + '. ';
798 * @param {boolean} sort_by_score
800 var resort_refutation_lines = function(sort_by_score) {
801 sort_refutation_lines_by_score = sort_by_score;
802 update_refutation_lines();
804 window['resort_refutation_lines'] = resort_refutation_lines;
807 * @param {boolean} truncate_history
809 var set_truncate_history = function(truncate_history) {
810 truncate_display_history = truncate_history;
811 update_refutation_lines();
813 window['set_truncate_history'] = set_truncate_history;
816 * @param {number} line_num
817 * @param {number} move_num
819 var show_line = function(line_num, move_num) {
820 if (line_num == -1) {
821 current_display_line = null;
822 current_display_move = null;
823 if (displayed_analysis_data) {
824 // TODO: Support exiting to history position if we are in an
825 // analysis line of a history position.
826 displayed_analysis_data = null;
827 update_board(current_analysis_data, displayed_analysis_data);
830 current_display_line = display_lines[line_num];
831 current_display_move = move_num;
833 current_display_line_is_history = (line_num == 0);
835 update_historic_analysis();
836 update_displayed_line();
840 window['show_line'] = show_line;
842 var prev_move = function() {
843 if (current_display_move > -1) {
844 --current_display_move;
846 update_historic_analysis();
847 update_displayed_line();
849 window['prev_move'] = prev_move;
851 var next_move = function() {
852 if (current_display_line && current_display_move < current_display_line.pretty_pv.length - 1) {
853 ++current_display_move;
855 update_historic_analysis();
856 update_displayed_line();
858 window['next_move'] = next_move;
860 var update_historic_analysis = function() {
861 if (!current_display_line_is_history) {
864 if (current_display_move == current_display_line.pretty_pv.length - 1) {
865 displayed_analysis_data = null;
866 update_board(current_analysis_data, displayed_analysis_data);
869 // Fetch old analysis for this line if it exists.
870 var hiddenboard = new Chess();
871 for (var i = 0; i <= current_display_move; ++i) {
872 hiddenboard.move(ucimove_to_chessjs_move(current_display_line.uci_pv[i]));
874 var filename = "/history/move" + (current_display_move + 1) + "-" +
875 hiddenboard.fen().replace(/ /g, '_').replace(/\//g, '-') + ".json";
879 }).done(function(data, textstatus, xhr) {
880 displayed_analysis_data = data;
881 update_board(current_analysis_data, displayed_analysis_data);
883 displayed_analysis_data = {'failed': true};
884 update_board(current_analysis_data, displayed_analysis_data);
888 var update_displayed_line = function() {
889 if (highlighted_move !== null) {
890 highlighted_move.removeClass('highlight');
892 if (current_display_line === null) {
893 $("#linenav").hide();
894 $("#linemsg").show();
899 $("#linenav").show();
900 $("#linemsg").hide();
902 if (current_display_move <= 0) {
903 $("#prevmove").html("Previous");
905 $("#prevmove").html("<a href=\"javascript:prev_move();\">Previous</a></span>");
907 if (current_display_move == current_display_line.uci_pv.length - 1) {
908 $("#nextmove").html("Next");
910 $("#nextmove").html("<a href=\"javascript:next_move();\">Next</a></span>");
913 var hiddenboard = new Chess();
914 hiddenboard.load(current_display_line.start_fen);
915 for (var i = 0; i <= current_display_move; ++i) {
916 hiddenboard.move(ucimove_to_chessjs_move(current_display_line.uci_pv[i]));
919 highlighted_move = $("#automove" + current_display_line.line_number + "-" + current_display_move);
920 highlighted_move.addClass('highlight');
922 board.position(hiddenboard.fen());
925 var ucimove_to_chessjs_move = function(move) {
926 var source = move.substr(0, 2);
927 var target = move.substr(2, 2);
928 var promo = move.substr(4, 1);
931 return { from: source, to: target };
933 return { from: source, to: target, promotion: promo };
937 var init = function() {
938 unique = get_unique();
941 board = new window.ChessBoard('board', 'start');
944 $(window).resize(function() {
949 $(window).keyup(function(event) {
950 if (event.which == 39) {
952 } else if (event.which == 37) {
957 $(document).ready(init);