/**
 * Plugin: jquery.zRSSFeed
 *
 * Version: 1.1.3
 * (c) Copyright 2010-2011, Zazar Ltd
 *
 * Description: jQuery plugin for display of RSS feeds via Google Feed API
 *              (Based on original plugin jGFeed by jQuery HowTo. Filesize function by Cary Dunn.)
 *
 * History:
 * 1.1.3 - Check for valid published date
 * 1.1.2 - Added user callback function due to issue with ajaxStop after jQuery 1.4.2
 * 1.1.1 - Correction to null xml entries and support for media with jQuery < 1.5
 * 1.1.0 - Added support for media in enclosure tags
 * 1.0.3 - Added feed link target
 * 1.0.2 - Fixed issue with GET parameters (Seb Dangerfield) and SSL option
 * 1.0.1 - Corrected issue with multiple instances
 *
 **/

(function($){

  $.fn.rssfeed = function(url, options, fn) {

    // Set pluign defaults
    var defaults = {
      limit: 10,
      header: true,
      titletag: '',
      date: true,
      content: true,
      snippet: true,
      showerror: true,
      errormsg: '',
      key: null,
      ssl: false,
      linktarget: '_self'
    };
    var options = $.extend(defaults, options);

    // Functions
    return this.each(function(i, e) {
      var $e = $(e);
      var s = '';

      // Check for SSL protocol
      if (options.ssl) s = 's';

      // Add feed class to user div
      if (!$e.hasClass('rssFeed')) $e.addClass('rssFeed');

      // Check for valid url
      if(url == null) return false;

      // Create Google Feed API address
      var api = "http"+ s +"://ajax.googleapis.com/ajax/services/feed/load?v=1.0&callback=?&q=" + encodeURIComponent(url);
      if (options.limit != null) api += "&num=" + options.limit;
      if (options.key != null) api += "&key=" + options.key;
      api += "&output=json_xml"

      // Send request
      $.getJSON(api, function(data){

        // Check for error
        if (data.responseStatus == 200) {

          // Process the feeds
          _process(e, data.responseData, options);

          // Optional user callback function
          if ($.isFunction(fn)) fn.call(this,$e);

        } else {

          // Handle error if required
          if (options.showerror)
            if (options.errormsg != '') {
              var msg = options.errormsg;
            } else {
              var msg = data.responseDetails;
            };
            $(e).html('<div class="rssError"><p>'+ msg +'</p></div>');
        };
      });
    });
  };

  // Function to create HTML result
  var _process = function(e, data, options) {

    // Get JSON feed data
    var feeds = data.feed;
    if (!feeds) {
      return false;
    }
    var html = '';
    var row = 'odd';

    // Get XML data for media (parseXML not used as requires 1.5+)
    var xml = getXMLDocument(data.xmlString);
    var xmlEntries = xml.getElementsByTagName('item');

    // Add header if required
    if (options.header)
      html += '<div class="rssHeader">' +
        '<a href="'+feeds.link+'" title="'+ feeds.description +'">'+ feeds.title +'</a>' +
        '</div>';

    // Add feeds
    for (var i=0; i<feeds.entries.length; i++) {

      // Get individual feed
      var entry = feeds.entries[i];
      var pubDate;

      // Format published date    日付関連の部分？
      if (entry.publishedDate) {
        var entryDate = new Date(entry.publishedDate);

        var yearNum = entryDate.getYear();
        if (yearNum < 2000) yearNum += 1900;

        var monthNum = ( entryDate.getMonth() + 1 );
        monthNum = ( "0" + monthNum ).substr(-2);

        var dayNum = entryDate.getDate();
        dayNum = ( "0" + dayNum ).substr(-2);

        var pubDate = yearNum + "." + monthNum + "." + dayNum;

        //var jpData = entryDate.toLocaleDateString();
        //var Rewrite  = jpData.split(/[\D]/);

        //if ( Rewrite[1].length == 1 ) Rewrite[1] = '0' + Rewrite[1];
        //if ( Rewrite[2].length == 1 ) Rewrite[2] = '0' + Rewrite[2];
        //var pubDate  = Rewrite[0] + '.' + Rewrite[1] + '.' + Rewrite[2];
        //var pubDate = entryDate.toLocaleDateString() + ' ' + entryDate.toLocaleTimeString();
      }

      // Add feed row    HTMLを組立てているの部分？
      //html += '<li class="rssRow '+row+'">' +
      //  '<'+ options.titletag +'><a href="'+ entry.link +'" title="View this feed at '+ feeds.title +'" target="'+ options.linktarget +'">'+ entry.title +'</a></'+ options.titletag +'>'
      //if (options.date && pubDate) html += '<div>'+ pubDate +'</div>'
      if (options.date && pubDate) html += '<dt>'+ pubDate +'</dt>'
      html += '<dd><a href="'+ entry.link +'" title="View this feed at '+ feeds.title +'" target="'+ options.linktarget +'">'+ entry.title +'</a></dd>'
      if (options.content) {

        // Use feed snippet if available and optioned
        if (options.snippet && entry.contentSnippet != '') {
          var content = entry.contentSnippet;
        } else {
          var content = entry.content;
        }

        html += '<p>'+ content +'</p>'
      }

      // Add any media
      if(xmlEntries.length > 0) {
        var xmlMedia = xmlEntries[i].getElementsByTagName('enclosure');
        if (xmlMedia.length > 0) {
          html += '<div class="rssMedia"><div>Media files</div><ul>'
          for (var m=0; m<xmlMedia.length; m++) {
            var xmlUrl = xmlMedia[m].getAttribute("url");
            var xmlType = xmlMedia[m].getAttribute("type");
            var xmlSize = xmlMedia[m].getAttribute("length");
            html += '<li><a href="'+ xmlUrl +'" title="Download this media">'+ xmlUrl.split('/').pop() +'</a> ('+ xmlType +', '+ formatFilesize(xmlSize) +')</li>';
          }
          html += '</ul></div>'
        }
        html += '</li>';
      }

      // Alternate row classes
      if (row == 'odd') {
        row = 'even';
      } else {
        row = 'odd';
      }
    }

    $(e).html(html);
  };

  function formatFilesize(bytes) {
    var s = ['bytes', 'kb', 'MB', 'GB', 'TB', 'PB'];
    var e = Math.floor(Math.log(bytes)/Math.log(1024));
    return (bytes/Math.pow(1024, Math.floor(e))).toFixed(2)+" "+s[e];
  }

  function getXMLDocument(string) {
    var browser = navigator.appName;
    var xml;
    if (browser == 'Microsoft Internet Explorer') {
      xml = new ActiveXObject('Microsoft.XMLDOM');
      xml.async = 'false'
      xml.loadXML(string);
    } else {
      xml = (new DOMParser()).parseFromString(string, 'text/xml');
    }
    return xml;
  }

})(jQuery);