+(function() {
+
+var board = null;
+var moves = [];
+var move_override = 0;
+
+var get_game = function() {
+ var game = new Chess();
+ for (var i = 0; i < move_override; ++i) {
+ game.move(moves[i]);
+ }
+ return game;
+}
+
+var update = function() {
+ var game = get_game();
+ board.position(game.fen());
+ fetch_analysis();
+}
+
+var fetch_analysis = function() {
+ var game = get_game();
+ $.ajax({
+ url: "/opening-stats.pl?fen=" + encodeURIComponent(game.fen())
+ }).done(function(data, textstatus, xhr) {
+ show_lines(data, game);
+ });
+}
+
+var add_td = function(tr, value) {
+ var td = document.createElement("td");
+ tr.appendChild(td);
+ $(td).addClass("num");
+ $(td).text(value);
+}
+
+var show_lines = function(data, game) {
+ var moves = data['moves'];
+ $('#numviewers').text(data['opening']);
+ var total_num = 0;
+ for (var i = 0; i < moves.length; ++i) {
+ var move = moves[i];
+ total_num += parseInt(move['white']);
+ total_num += parseInt(move['draw']);
+ total_num += parseInt(move['black']);
+ }
+
+ var tbl = $("#lines");
+ tbl.empty();
+
+ for (var i = 0; i < moves.length; ++i) {
+ var move = moves[i];
+ var tr = document.createElement("tr");
+
+ var white = parseInt(move['white']);
+ var draw = parseInt(move['draw']);
+ var black = parseInt(move['black']);
+
+ // Move.
+ var move_td = document.createElement("td");
+ tr.appendChild(move_td);
+ $(move_td).addClass("move");
+
+ var move_a = document.createElement("a");
+ move_a.href = "javascript:make_move('" + move['move'] + "')";
+ move_td.appendChild(move_a);
+ $(move_a).text(move['move']);
+
+ // #.
+ var num = white + draw + black;
+ add_td(tr, num);
+
+ // %.
+ add_td(tr, (100.0 * num / total_num).toFixed(1) + "%");
+
+ // Win%.
+ var white_win_ratio = (white + 0.5 * draw) / num;
+ var win_ratio = (game.turn() == 'w') ? white_win_ratio : 1.0 - white_win_ratio;
+ add_td(tr, ((100.0 * win_ratio).toFixed(1) + "%"));
+
+ // Elo.
+ add_td(tr, move['white_avg_elo'].toFixed(1));
+ add_td(tr, move['black_avg_elo'].toFixed(1));
+
+ // Win% corrected for Elo.
+ var win_elo = -400.0 * Math.log(1.0 / white_win_ratio - 1.0) / Math.LN10;
+ win_elo -= (move['white_avg_elo'] - move['black_avg_elo']);
+ white_win_ratio = 1.0 / (1.0 + Math.pow(10, win_elo / -400.0));
+ win_ratio = (game.turn() == 'w') ? white_win_ratio : 1.0 - white_win_ratio;
+ add_td(tr, ((100.0 * win_ratio).toFixed(1) + "%"));
+
+ if (false) {
+ // Win bars (W/D/B).
+ var winbar_td = document.createElement("td");
+ $(winbar_td).addClass("winbars");
+ tr.appendChild(winbar_td);
+ var winbar_table = document.createElement("table");
+ winbar_td.appendChild(winbar_table);
+ var winbar_tr = document.createElement("tr");
+ winbar_table.appendChild(winbar_tr);
+
+ if (white > 0) {
+ var white_percent = (100.0 * white / num).toFixed(0) + "%";
+ var white_td = document.createElement("td");
+ winbar_tr.appendChild(white_td);
+ $(white_td).addClass("white");
+ white_td.style.width = white_percent;
+ $(white_td).text(white_percent);
+ }
+ if (draw > 0) {
+ var draw_percent = (100.0 * draw / num).toFixed(0) + "%";
+ var draw_td = document.createElement("td");
+ winbar_tr.appendChild(draw_td);
+ $(draw_td).addClass("draw");
+ draw_td.style.width = draw_percent;
+ $(draw_td).text(draw_percent);
+ }
+ if (black > 0) {
+ var black_percent = (100.0 * black / num).toFixed(0) + "%";
+ var black_td = document.createElement("td");
+ winbar_tr.appendChild(black_td);
+ $(black_td).addClass("black");
+ black_td.style.width = black_percent;
+ $(black_td).text(black_percent);
+ }
+ }
+
+ tbl.append(tr);
+ }
+}
+
+var make_move = function(move) {
+ moves.length = move_override;
+ moves.push(move);
+ move_override = moves.length;
+ update();
+}
+window['make_move'] = make_move;
+
+var prev_move = function() {
+ if (move_override > 0) {
+ --move_override;
+ update();
+ }
+}
+window['prev_move'] = prev_move;
+
+var next_move = function() {
+ if (move_override < moves.length) {
+ ++move_override;
+ update();
+ }
+}
+window['next_move'] = next_move;
+
+// almost all of this stuff comes from the chessboard.js example page
+var onDragStart = function(source, piece, position, orientation) {
+ var game = get_game();
+ if (game.game_over() === true ||
+ (game.turn() === 'w' && piece.search(/^b/) !== -1) ||
+ (game.turn() === 'b' && piece.search(/^w/) !== -1)) {
+ return false;
+ }
+}
+
+var onDrop = function(source, target) {
+ // see if the move is legal
+ var game = get_game();
+ var move = game.move({
+ from: source,
+ to: target,
+ promotion: 'q' // NOTE: always promote to a queen for example simplicity
+ });
+
+ // illegal move
+ if (move === null) return 'snapback';
+
+ moves = game.history({ verbose: true });
+ move_override = moves.length;
+};
+
+// update the board position after the piece snap
+// for castling, en passant, pawn promotion
+var onSnapEnd = function() {
+ var game = get_game();
+ board.position(game.fen());
+ fetch_analysis();
+};
+
+var init = function() {
+ // Create board.
+ board = new window.ChessBoard('board', {
+ draggable: true,
+ position: 'start',
+ onDragStart: onDragStart,
+ onDrop: onDrop,
+ onSnapEnd: onSnapEnd
+ });
+ update();
+
+ $(window).keyup(function(event) {
+ if (event.which == 39) {
+ next_move();
+ } else if (event.which == 37) {
+ prev_move();
+ }
+ });
+}
+
+
+$(document).ready(init);
+
+})();