text: // https://github.com/ghiculescu/jekyll-table-of-contents
  // Updated by http://hyosunghan.github.io
  (function($){
    $.fn.toc = function(options) {
      var defaults = {
        noBackToTopLinks: false,
        title: '文章目录',
        minimumHeaders: 2,
        headers: 'h1, h2, h3, h4, h5, h6',
        listType: 'ul', // values: [ol|ul]
        showEffect: 'show', // values: [show|slideDown|fadeIn|none]
        showSpeed: 0 // set to 0 to deactivate effect
      },
      settings = $.extend(defaults, options);
  
      function fixedEncodeURIComponent (str) {
        return encodeURIComponent(str).replace(/[!'()*]/g, function(c) {
          return '%' + c.charCodeAt(0).toString(16);
        });
      }
  
      var headers = $(settings.headers).filter(function() {
        // get all headers with an ID
        var previousSiblingName = $(this).prev().attr( "name" );
        if (!this.id && previousSiblingName) {
          this.id = $(this).attr( "id", previousSiblingName.replace(/\./g, "-") );
        }
        return this.id;
      }), output = $(this);
      if (!headers.length || headers.length < settings.minimumHeaders || !output.length) {
        $(this).hide();
        $('.post-directory-title').css('display', 'none');
        return;
      }
  
      if (0 === settings.showSpeed) {
        settings.showEffect = 'none';
      }
  
      var render = {
        show: function() { output.hide().html(html).show(settings.showSpeed); },
        slideDown: function() { output.hide().html(html).slideDown(settings.showSpeed); },
        fadeIn: function() { output.hide().html(html).fadeIn(settings.showSpeed); },
        none: function() { output.html(html); }
      };
  
      var get_level = function(ele) { return parseInt(ele.nodeName.replace("H", ""), 10); }
      var highest_level = headers.map(function(_, ele) { return get_level(ele); }).get().sort()[0];
      var return_to_top = '<i class="icon-arrow-up back-to-top"> </i>';
  
      var level = get_level(headers[0]),
      this_level,
      html = "<p><strong class=\"toc-title\">" + settings.title + "</strong></p>\n";
      html += " <"+settings.listType+" class=\"toc\">";
      headers.on('click', function() {
        if (!settings.noBackToTopLinks) {
          window.location.hash = this.id;
        }
      })
      .addClass('clickable-header')
      .each(function(_, header) {
        this_level = get_level(header);
        if (!settings.noBackToTopLinks && this_level === highest_level) {
          $(header).addClass('top-level-header').after(return_to_top);
        }
        if (this_level === level) {// same level as before; same indenting
          html += "<li class=\"toc-item toc-level-" + this_level + "\">";
          html += "<a class=\"jumper\" href='#" + fixedEncodeURIComponent(header.id) + "'>";
          html += "<span class='toc-text'>" + header.innerHTML + "</span>";
          html += "</a>";
  
        } else if (this_level <= level){ // higher level than before; end parent ol
          for(i = this_level; i < level; i++) {
            html += "</li></"+settings.listType+">"
          }
          html += "<li class='toc-item toc-level-" + this_level + "'><a class=\"jumper\" href='#" + fixedEncodeURIComponent(header.id) + "'>";
          html += "<span class='toc-text'>" + header.innerHTML + "</span>";
          html += "</a>";
        }
        else if (this_level > level) { // lower level than before; expand the previous to contain a ol
          for(i = this_level; i > level; i--) {
            html += "<"+settings.listType+" class='toc-child'><li class='toc-item toc-level-" + i + "'>"
          }
          html += "<a class=\"jumper\" href='#" + fixedEncodeURIComponent(header.id) + "'>";
          html += "<span class='toc-text'>" + header.innerHTML + "</span>";
          html += "</a>";
        }
        level = this_level; // update for the next one
      });
      html += "</"+settings.listType+">";
      if (!settings.noBackToTopLinks) {
        $(document).on('click', '.back-to-top', function() {
          $(window).scrollTop(0);
          window.location.hash = '';
        });
      }
  
      render[settings.showEffect]();
    };
  })(jQuery);
  
  $(document).ready(function(){
    $('.post-directory').toc();
  
    var fixmeTop = $('#post-directory-module').offset().top;
    var tocSections = $('.clickable-header');
    var tocSectionOffsets = [];
  
    var calculateTocSections = function(){
      tocSectionOffsets = [];
      tocSections.each(function(index, section){
        tocSectionOffsets.push(section.offsetTop);
      })
    }
    calculateTocSections();
    // Calculates the toc section offsets, which can change as images get loaded
    $(window).bind('load', calculateTocSections);
  
    var highlightTocSection = function(){
      var highlightIndex = 0;
      var sectionsCount = tocSectionOffsets.length;
      var currentScroll = $(window).scrollTop();
  
      if (currentScroll+60 > tocSectionOffsets[sectionsCount-1]) {
        highlightIndex = sectionsCount;
      } else {
        for (var i=0; i<sectionsCount; i++) {
          if (currentScroll+60 <= tocSectionOffsets[i]) {
            highlightIndex = i;
            break;
          }
        }
      }
      if (highlightIndex == 0) {
        highlightIndex += 1;
      }
      $('.toc-item .jumper').removeClass('on');
      $('.toc-item .jumper').eq(highlightIndex-1).addClass('on');
    }
    highlightTocSection();
  
    var updateTocHeight = function() {
        var height = document.documentElement.clientHeight;
        height = height || 'auto';
        $('.post-directory').css('max-height', height);
    }
  
    $(window).scroll(function() {
      var currentScroll = $(window).scrollTop();
      if (currentScroll >= fixmeTop) {
        $('#post-directory-module').css({
          top: '0',
          position: 'fixed',
          width: 'inherit'
        });
        $('.post-directory').css('overflow', 'auto');
      } else {
        $('#post-directory-module').css({
          position: 'inherit',
          width: 'inherit'
        });
        $('.post-directory').css('overflow', 'hidden');
        $('.post-directory').scrollTop(0);
      }
  
      highlightTocSection();
    });
  
    updateTocHeight();
  
    $(window).on("resize", function() {
        updateTocHeight();
    });
  });
  
  $(".jumper").on("click", function( e ) {
    e.preventDefault();
    $("body, html").animate({
      scrollTop: $( $(this).attr('href') ).offset().top
    }, 600);
  });
  