popcorn-js/plugins/wikipedia/popcorn.wikipedia.js

// PLUGIN: WIKIPEDIA


var wikiCallback;

(function ( Popcorn ) {
  
  /**
   * Wikipedia popcorn plug-in 
   * Displays a wikipedia aricle in the target specified by the user by using
   * new DOM element instead overwriting them
   * Options parameter will need a start, end, target, lang, src, title and numberofwords.
   * -Start is the time that you want this plug-in to execute
   * -End is the time that you want this plug-in to stop executing 
   * -Target is the id of the document element that the text from the article needs to be  
   * attached to, this target element must exist on the DOM
   * -Lang (optional, defaults to english) is the language in which the article is in.
   * -Src is the url of the article 
   * -Title (optional) is the title of the article
   * -numberofwords (optional, defaults to 200) is  the number of words you want displaid.  
   *
   * @param {Object} options
   * 
   * Example:
     var p = Popcorn("#video")
        .wikipedia({
          start: 5, // seconds
          end: 15, // seconds
          src: "http://en.wikipedia.org/wiki/Cape_Town",
          target: "wikidiv"
        } )
   *
   */
  Popcorn.plugin( "wikipedia" , {
      
    manifest: {
      about:{
        name: "Popcorn Wikipedia Plugin",
        version: "0.1",
        author: "@annasob",
        website: "annasob.wordpress.com"
      },
      options:{
        start: {
          elem: "input", 
          type: "text", 
          label: "In"
        },
        end: {
          elem: "input", 
          type: "text", 
          label: "Out"
        },
        lang: {
          elem: "input", 
          type: "text", 
          label: "Language",
          optional: true
        },
        src: {
          elem: "input", 
          type: "url", 
          label: "Src"
        },
        title: {
          elem: "input", 
          type: "text", 
          label: "Title",
          optional: true
        },
        numberofwords: {
          elem: "input", 
          type: "text", 
          label: "Num Of Words",
          optional: true
        },
        target: "wikipedia-container"
      }
    },
    /**
     * @member wikipedia 
     * The setup function will get all of the needed 
     * items in place before the start function is called. 
     * This includes getting data from wikipedia, if the data
     * is not received and processed before start is called start 
     * will not do anything
     */
    _setup : function( options ) {
      // declare needed variables
      // get a guid to use for the global wikicallback function
      var  _text, _guid = Popcorn.guid(); 
      
      // if the user didn't specify a language default to english
      if ( !options.lang ) { 
        options.lang = "en"; 
      }

      // if the user didn't specify number of words to use default to 200 
      options.numberofwords  = options.numberofwords || 200;
            
      // wiki global callback function with a unique id
      // function gets the needed information from wikipedia
      // and stores it by appending values to the options object
      window[ "wikiCallback" + _guid ]  = function ( data ) { 

        options._link = document.createElement( "a" );
        options._link.setAttribute( "href", options.src );
        options._link.setAttribute( "target", "_blank" );

        // add the title of the article to the link
        options._link.innerHTML = options.title || data.parse.displaytitle;

        // get the content of the wiki article
        options._desc = document.createElement( "p" );

        // get the article text and remove any special characters
        _text = data.parse.text[ "*" ].substr( data.parse.text[ "*" ].indexOf( "<p>" ) );
        _text = _text.replace( /((<(.|\n)+?>)|(\((.*?)\) )|(\[(.*?)\]))/g, "" );
        
        _text = _text.split( " " );
        options._desc.innerHTML = ( _text.slice( 0, ( _text.length >= options.numberofwords ? options.numberofwords : _text.length ) ).join (" ") + " ..." ) ;
        
        options._fired = true;
      };
      
      if ( options.src ) {
        Popcorn.getScript( "//" + options.lang + ".wikipedia.org/w/api.php?action=parse&props=text&page=" + 
          options.src.slice( options.src.lastIndexOf( "/" ) + 1 )  + "&format=json&callback=wikiCallback" + _guid );
      } else if ( Popcorn.plugin.debug ) {
        throw new Error( "Wikipedia plugin needs a 'src'" );
      }

    },
    /**
     * @member wikipedia 
     * The start function will be executed when the currentTime 
     * of the video  reaches the start time provided by the 
     * options variable
     */
    start: function( event, options ){
      // dont do anything if the information didn't come back from wiki
      var isReady = function () {
        
        if ( !options._fired ) {
          setTimeout( function () {
            isReady();
          }, 13);
        } else {
      
          if ( options._link && options._desc ) {
            if ( document.getElementById( options.target ) ) {
              document.getElementById( options.target ).appendChild( options._link );
              document.getElementById( options.target ).appendChild( options._desc );
              options._added = true;
            }
          }
        }
      };
      
      isReady();
    },
    /**
     * @member wikipedia 
     * The end function will be executed when the currentTime 
     * of the video  reaches the end time provided by the 
     * options variable
     */
    end: function( event, options ){
      // ensure that the data was actually added to the 
      // DOM before removal
      if ( options._added ) {
        document.getElementById( options.target ).removeChild( options._link );
        document.getElementById( options.target ).removeChild( options._desc );
      }
    },

    _teardown: function( options ){

      if ( options._added ) {
        options._link.parentNode && document.getElementById( options.target ).removeChild( options._link );
        options._desc.parentNode && document.getElementById( options.target ).removeChild( options._desc );
        delete options.target;
      }
    }
  });

})( Popcorn );