https://moderndive.com/libs/gitbook-2.6.7/js/plugin-bookdown.js

1gitbook.require(["gitbook", "lodash", "jQuery"], function(gitbook, _, $) {
2
3  var gs = gitbook.storage;
4
5  gitbook.events.bind("start", function(e, config) {
6
7    // add the Edit button (edit on Github)
8    var edit = config.edit;
9    if (edit && edit.link) gitbook.toolbar.createButton({
10      icon: 'fa fa-edit',
11      label: edit.text || 'Edit',
12      position: 'left',
13      onClick: function(e) {
14        e.preventDefault();
15        window.open(edit.link);
16      }
17    });
18
19    // add the History button (file history on Github)
20    var history = config.history;
21    if (history && history.link) gitbook.toolbar.createButton({
22      icon: 'fa fa-history',
23      label: history.text || 'History',
24      position: 'left',
25      onClick: function(e) {
26        e.preventDefault();
27        window.open(history.link);
28      }
29    });
30
31    // add the View button (file view on Github)
32    var view = config.view;
33    if (view && view.link) gitbook.toolbar.createButton({
34      icon: 'fa fa-eye',
35      label: view.text || 'View Source',
36      position: 'left',
37      onClick: function(e) {
38        e.preventDefault();
39        window.open(view.link);
40      }
41    });
42
43    // add the Download button
44    var down = config.download;
45    var normalizeDownload = function() {
46      if (!down || !(down instanceof Array) || down.length === 0) return;
47      if (down[0] instanceof Array) return down;
48      return $.map(down, function(file, i) {
49        return [[file, file.replace(/.*[.]/g, '').toUpperCase()]];
50      });
51    };
52    down = normalizeDownload(down);
53    if (down) if (down.length === 1 && /[.]pdf$/.test(down[0][0])) {
54      gitbook.toolbar.createButton({
55        icon: 'fa fa-file-pdf-o',
56        label: down[0][1],
57        position: 'left',
58        onClick: function(e) {
59          e.preventDefault();
60          window.open(down[0][0]);
61        }
62      });
63    } else {
64      gitbook.toolbar.createButton({
65        icon: 'fa fa-download',
66        label: 'Download',
67        position: 'left',
68        dropdown: $.map(down, function(item, i) {
69          return {
70            text: item[1],
71            onClick: function(e) {
72              e.preventDefault();
73              window.open(item[0]);
74            }
75          };
76        })
77      });
78    }
79
80    // add the Information button
81    var info = ['Keyboard shortcuts (<> indicates arrow keys):',
82      '<left>/<right>: navigate to previous/next page',
83      's: Toggle sidebar'];
84    if (config.search !== false) info.push('f: Toggle search input ' +
85      '(use <up>/<down>/Enter in the search input to navigate through search matches; ' +
86      'press Esc to cancel search)');
87    if (config.info !== false) gitbook.toolbar.createButton({
88      icon: 'fa fa-info',
89      label: 'Information about the toolbar',
90      position: 'left',
91      onClick: function(e) {
92        e.preventDefault();
93        window.alert(info.join('\n\n'));
94      }
95    });
96
97    // highlight the current section in TOC
98    var href = window.location.pathname;
99    href = href.substr(href.lastIndexOf('/') + 1);
100    // accentuated characters need to be decoded (#819)
101    href = decodeURIComponent(href);
102    if (href === '') href = 'index.html';
103    var li = $('a[href^="' + href + location.hash + '"]').parent('li.chapter').first();
104    var summary = $('ul.summary'), chaps = summary.find('li.chapter');
105    if (li.length === 0) li = chaps.first();
106    li.addClass('active');
107    chaps.on('click', function(e) {
108      chaps.removeClass('active');
109      $(this).addClass('active');
110      gs.set('tocScrollTop', summary.scrollTop());
111    });
112
113    var toc = config.toc;
114    // collapse TOC items that are not for the current chapter
115    if (toc && toc.collapse) (function() {
116      var type = toc.collapse;
117      if (type === 'none') return;
118      if (type !== 'section' && type !== 'subsection') return;
119      // sections under chapters
120      var toc_sub = summary.children('li[data-level]').children('ul');
121      if (type === 'section') {
122        toc_sub.hide()
123          .parent().has(li).children('ul').show();
124      } else {
125        toc_sub.children('li').children('ul').hide()
126          .parent().has(li).children('ul').show();
127      }
128      li.children('ul').show();
129      var toc_sub2 = toc_sub.children('li');
130      if (type === 'section') toc_sub2.children('ul').hide();
131      summary.children('li[data-level]').find('a')
132        .on('click.bookdown', function(e) {
133          if (href === $(this).attr('href').replace(/#.*/, ''))
134            $(this).parent('li').children('ul').toggle();
135        });
136    })();
137
138    // add tooltips to the <a>'s that are truncated
139    $('a').each(function(i, el) {
140      if (el.offsetWidth >= el.scrollWidth) return;

141      if (typeof el.title === 'undefined') return;
142      el.title = el.text;
143    });
144
145    // restore TOC scroll position
146    var pos = gs.get('tocScrollTop');
147    if (typeof pos !== 'undefined') summary.scrollTop(pos);
148
149    // highlight the TOC item that has same text as the heading in view as scrolling
150    if (toc && toc.scroll_highlight !== false && li.length > 0) (function() {
151      // scroll the current TOC item into viewport
152      var ht = $(window).height(), rect = li[0].getBoundingClientRect();
153      if (rect.top >= ht || rect.top <= 0 || rect.bottom <= 0) {
154        summary.scrollTop(li[0].offsetTop);
155      }
156      // current chapter TOC items
157      var items = $('a[href^="' + href + '"]').parent('li.chapter'),
158          m = items.length;
159      if (m === 0) {
160        items = summary.find('li.chapter');
161        m = items.length;
162      }
163      if (m === 0) return;
164      // all section titles on current page
165      var hs = bookInner.find('.page-inner').find('h1,h2,h3'), n = hs.length,
166          ts = hs.map(function(i, el) { return $(el).text(); });
167      if (n === 0) return;
168      var scrollHandler = function(e) {
169        var ht = $(window).height();
170        clearTimeout($.data(this, 'scrollTimer'));
171        $.data(this, 'scrollTimer', setTimeout(function() {
172          // find the first visible title in the viewport
173          for (var i = 0; i < n; i++) {
174            var rect = hs[i].getBoundingClientRect();
175            if (rect.top >= 0 && rect.bottom <= ht) break;
176          }
177          if (i === n) return;
178          items.removeClass('active');
179          for (var j = 0; j < m; j++) {
180            if (items.eq(j).children('a').first().text() === ts[i]) break;
181          }
182          if (j === m) j = 0;  // highlight the chapter title
183          // search bottom-up for a visible TOC item to highlight; if an item is
184          // hidden, we check if its parent is visible, and so on
185          while (j > 0 && items.eq(j).is(':hidden')) j--;
186          items.eq(j).addClass('active');
187        }, 250));
188      };
189      bookInner.on('scroll.bookdown', scrollHandler);
190      bookBody.on('scroll.bookdown', scrollHandler);
191    })();
192
193    // do not refresh the page if the TOC item points to the current page
194    $('a[href="' + href + '"]').parent('li.chapter').children('a')
195      .on('click', function(e) {
196        bookInner.scrollTop(0);
197        bookBody.scrollTop(0);
198        return false;
199      });
200
201    var toolbar = config.toolbar;
202    if (!toolbar || toolbar.position !== 'static') {
203      var bookHeader = $('.book-header');
204      bookBody.addClass('fixed');
205      bookHeader.addClass('fixed')
206      .css('background-color', bookBody.css('background-color'))
207      .on('click.bookdown', function(e) {
208        // the theme may have changed after user clicks the theme button
209        bookHeader.css('background-color', bookBody.css('background-color'));
210      });
211    }
212
213  });
214
215  gitbook.events.bind("page.change", function(e) {
216    // store TOC scroll position
217    var summary = $('ul.summary');
218    gs.set('tocScrollTop', summary.scrollTop());
219  });
220
221  var bookBody = $('.book-body'), bookInner = bookBody.find('.body-inner');
222  var chapterTitle = function() {
223    return bookInner.find('.page-inner').find('h1,h2').first().text();
224  };
225  var saveScrollPos = function(e) {
226    // save scroll position before page is reloaded
227    gs.set('bodyScrollTop', {
228      body: bookBody.scrollTop(),
229      inner: bookInner.scrollTop(),
230      focused: document.hasFocus(),
231      title: chapterTitle()
232    });
233  };
234  $(document).on('servr:reload', saveScrollPos);
235
236  // check if the page is loaded in an iframe (e.g. the RStudio preview window)
237  var inIFrame = function() {
238    var inIframe = true;
239    try { inIframe = window.self !== window.top; } catch (e) {}
240    return inIframe;
241  };
242  if (inIFrame()) {
243    $(window).on('blur unload', saveScrollPos);
244  }
245
246  $(function(e) {
247    var pos = gs.get('bodyScrollTop');
248    if (pos) {
249      if (pos.title === chapterTitle()) {
250        if (pos.body !== 0) bookBody.scrollTop(pos.body);
251        if (pos.inner !== 0) bookInner.scrollTop(pos.inner);
252      }
253    }
254    if ((pos && pos.focused) || !inIFrame()) bookInner.find('.page-wrapper').focus();
255    // clear book body scroll position
256    gs.remove('bodyScrollTop');
257  });
258
259});