hugo-academic/static/js/vendor/reveal.js/plugin/notes/notes.js

/**
 * Handles opening of and synchronization with the reveal.js
 * notes window.
 *
 * Handshake process:
 * 1. This window posts 'connect' to notes window
 *    - Includes URL of presentation to show
 * 2. Notes window responds with 'connected' when it is available
 * 3. This window proceeds to send the current presentation state
 *    to the notes window
 */
var RevealNotes = (function() {

  function openNotes( notesFilePath ) {

    if( !notesFilePath ) {
      var jsFileLocation = document.querySelector('script[src$="notes.js"]').src;  // this js file path
      jsFileLocation = jsFileLocation.replace(/notes\.js(\?.*)?$/, '');   // the js folder path
      notesFilePath = jsFileLocation + 'notes.html';
    }

    var notesPopup = window.open( notesFilePath, 'reveal.js - Notes', 'width=1100,height=700' );

    if( !notesPopup ) {
      alert( 'Speaker view popup failed to open. Please make sure popups are allowed and reopen the speaker view.' );
      return;
    }

    // Allow popup window access to Reveal API
    notesPopup.Reveal = window.Reveal;

    /**
     * Connect to the notes window through a postmessage handshake.
     * Using postmessage enables us to work in situations where the
     * origins differ, such as a presentation being opened from the
     * file system.
     */
    function connect() {
      // Keep trying to connect until we get a 'connected' message back
      var connectInterval = setInterval( function() {
        notesPopup.postMessage( JSON.stringify( {
          namespace: 'reveal-notes',
          type: 'connect',
          url: window.location.protocol + '//' + window.location.host + window.location.pathname + window.location.search,
          state: Reveal.getState()
        } ), '*' );
      }, 500 );

      window.addEventListener( 'message', function( event ) {
        var data = JSON.parse( event.data );
        if( data && data.namespace === 'reveal-notes' && data.type === 'connected' ) {
          clearInterval( connectInterval );
          onConnected();
        }
      } );
    }

    /**
     * Posts the current slide data to the notes window
     */
    function post( event ) {

      var slideElement = Reveal.getCurrentSlide(),
        notesElement = slideElement.querySelector( 'aside.notes' ),
        fragmentElement = slideElement.querySelector( '.current-fragment' );

      var messageData = {
        namespace: 'reveal-notes',
        type: 'state',
        notes: '',
        markdown: false,
        whitespace: 'normal',
        state: Reveal.getState()
      };

      // Look for notes defined in a slide attribute
      if( slideElement.hasAttribute( 'data-notes' ) ) {
        messageData.notes = slideElement.getAttribute( 'data-notes' );
        messageData.whitespace = 'pre-wrap';
      }

      // Look for notes defined in a fragment
      if( fragmentElement ) {
        var fragmentNotes = fragmentElement.querySelector( 'aside.notes' );
        if( fragmentNotes ) {
          notesElement = fragmentNotes;
        }
        else if( fragmentElement.hasAttribute( 'data-notes' ) ) {
          messageData.notes = fragmentElement.getAttribute( 'data-notes' );
          messageData.whitespace = 'pre-wrap';

          // In case there are slide notes
          notesElement = null;
        }
      }

      // Look for notes defined in an aside element
      if( notesElement ) {
        messageData.notes = notesElement.innerHTML;
        messageData.markdown = typeof notesElement.getAttribute( 'data-markdown' ) === 'string';
      }

      notesPopup.postMessage( JSON.stringify( messageData ), '*' );

    }

    /**
     * Called once we have established a connection to the notes
     * window.
     */
    function onConnected() {

      // Monitor events that trigger a change in state
      Reveal.addEventListener( 'slidechanged', post );
      Reveal.addEventListener( 'fragmentshown', post );
      Reveal.addEventListener( 'fragmenthidden', post );
      Reveal.addEventListener( 'overviewhidden', post );
      Reveal.addEventListener( 'overviewshown', post );
      Reveal.addEventListener( 'paused', post );
      Reveal.addEventListener( 'resumed', post );

      // Post the initial state
      post();

    }

    connect();

  }

  if( !/receiver/i.test( window.location.search ) ) {

    // If the there's a 'notes' query set, open directly
    if( window.location.search.match( /(\?|\&)notes/gi ) !== null ) {
      openNotes();
    }

    // Open the notes when the 's' key is hit
    Reveal.addKeyBinding({keyCode: 83, key: 'S', description: 'Speaker notes view'}, function() {
      openNotes();
    } );

  }

  return { open: openNotes };

})();