/*
  Copyright (c) 2011 DaWanda GmbH
  Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
  The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
(function ($) {
  'use strict';

  var RSS = function (target, url, options, callback) {
    this.target       = target;

    this.url          = url;
    this.html         = [];
    this.effectQueue  = [];

    this.options = $.extend({
      ssl: false,
      host: 'www.feedrapp.info',
      limit: null,
      key: null,
      layoutTemplate: '<ul>{entries}</ul>',
      entryTemplate: '<li><a href="{url}">[{author}@{date}] {title}</a><br/>{shortBodyPlain}</li>',
      tokens: {},
      outputMode: 'json',
      dateFormat: 'dddd MMM Do',
      dateLocale: 'en',
      effect: 'show',
      offsetStart: false,
      offsetEnd: false,
      error: function () {
        console.log('jQuery RSS: url doesn\'t link to RSS-Feed');
      },
      onData: function () {},
      success: function () {}
    }, options || {});

    this.callback = callback || this.options.success;
  };

  RSS.htmlTags = [
    'doctype', 'html', 'head', 'title', 'base', 'link', 'meta', 'style', 'script', 'noscript',
    'body', 'article', 'nav', 'aside', 'section', 'header', 'footer', 'h1-h6', 'hgroup', 'address',
    'p', 'hr', 'pre', 'blockquote', 'ol', 'ul', 'li', 'dl', 'dt', 'dd', 'figure', 'figcaption',
    'div', 'table', 'caption', 'thead', 'tbody', 'tfoot', 'tr', 'th', 'td', 'col', 'colgroup',
    'form', 'fieldset', 'legend', 'label', 'input', 'button', 'select', 'datalist', 'optgroup',
    'option', 'textarea', 'keygen', 'output', 'progress', 'meter', 'details', 'summary', 'command',
    'menu', 'del', 'ins', 'img', 'iframe', 'embed', 'object', 'param', 'video', 'audio', 'source',
    'canvas', 'track', 'map', 'area', 'a', 'em', 'strong', 'i', 'b', 'u', 's', 'small', 'abbr', 'q',
    'cite', 'dfn', 'sub', 'sup', 'time', 'code', 'kbd', 'samp', 'var', 'mark', 'bdi', 'bdo', 'ruby',
    'rt', 'rp', 'span', 'br', 'wbr'
  ];

  RSS.prototype.load = function (callback) {
    var apiProtocol = 'http' + (this.options.ssl ? 's' : '');
    var apiHost     = apiProtocol + '://' + this.options.host;
    var apiUrl      = apiHost + '?callback=?&q=' + encodeURIComponent(this.url);

    // set limit to offsetEnd if offset has been set
    if (this.options.offsetStart && this.options.offsetEnd) {
      this.options.limit = this.options.offsetEnd;
    }

    if (this.options.limit !== null) {
      apiUrl += '&num=' + this.options.limit;
    }

    if (this.options.key !== null) {
      apiUrl += '&key=' + this.options.key;
    }

    $.getJSON(apiUrl, callback);
  };

  RSS.prototype.render = function () {
    var self = this;

    this.load(function (data) {
      try {
        self.feed    = data.responseData.feed;
        self.entries = data.responseData.feed.entries;
      } catch (e) {
        self.entries = [];
        self.feed    = null;
        return self.options.error.call(self);
      }

      var html = self.generateHTMLForEntries();

      self.target.append(html.layout);

      if (html.entries.length !== 0) {
        if ($.isFunction(self.options.onData)) {
          self.options.onData.call(self);
        }

        var container = $(html.layout).is('entries') ? html.layout : $('entries', html.layout);

        self.appendEntriesAndApplyEffects(container, html.entries);
      }

      if (self.effectQueue.length > 0) {
        self.executeEffectQueue(self.callback);
      } else if ($.isFunction(self.callback)) {
        self.callback.call(self);
      }
    });
  };

  RSS.prototype.appendEntriesAndApplyEffects = function (target, entries) {
    var self = this;

    $.each(entries, function (idx, entry) {
      var $html = self.wrapContent(entry);

      if (self.options.effect === 'show') {
        target.before($html);
      } else {
        $html.css({ display: 'none' });
        target.before($html);
        self.applyEffect($html, self.options.effect);
      }
    });

    target.remove();
  };

  RSS.prototype.generateHTMLForEntries = function () {
    var self   = this;
    var result = { entries: [], layout: null };

    $(this.entries).each(function () {
      var entry       = this;
      var offsetStart = self.options.offsetStart;
      var offsetEnd   = self.options.offsetEnd;
      var evaluatedString;

      // offset required
      if (offsetStart && offsetEnd) {
        if (index >= offsetStart && index <= offsetEnd) {
          if (self.isRelevant(entry, result.entries)) {
            evaluatedString = self.evaluateStringForEntry(
              self.options.entryTemplate, entry
            );

            result.entries.push(evaluatedString);
          }
        }
      } else {
        // no offset
        if (self.isRelevant(entry, result.entries)) {
          evaluatedString = self.evaluateStringForEntry(
            self.options.entryTemplate, entry
          );

          result.entries.push(evaluatedString);
        }
      }
    });

    if (!!this.options.entryTemplate) {
      // we have an entryTemplate
      result.layout = this.wrapContent(
        this.options.layoutTemplate.replace('{entries}', '<entries></entries>')
      );
    } else {
      // no entryTemplate available
      result.layout = this.wrapContent('<div><entries></entries></div>');
    }

    return result;
  };

  RSS.prototype.wrapContent = function (content) {
    if (($.trim(content).indexOf('<') !== 0)) {
      // the content has no html => create a surrounding div
      return $('<div>' + content + '</div>');
    } else {
      // the content has html => don't touch it
      return $(content);
    }
  };

  RSS.prototype.applyEffect = function ($element, effect, callback) {
    var self = this;

    switch (effect) {
      case 'slide':
        $element.slideDown('slow', callback);
        break;
      case 'slideFast':
        $element.slideDown(callback);
        break;
      case 'slideSynced':
        self.effectQueue.push({ element: $element, effect: 'slide' });
        break;
      case 'slideFastSynced':
        self.effectQueue.push({ element: $element, effect: 'slideFast' });
        break;
    }
  };

  RSS.prototype.executeEffectQueue = function (callback) {
    var self = this;

    this.effectQueue.reverse();

    var executeEffectQueueItem = function () {
      var item = self.effectQueue.pop();

      if (item) {
        self.applyEffect(item.element, item.effect, executeEffectQueueItem);
      } else if (callback) {
        callback();
      }
    };

    executeEffectQueueItem();
  };

  RSS.prototype.evaluateStringForEntry = function (string, entry) {
    var result = string;
    var self   = this;

    $(string.match(/(\{.*?\})/g)).each(function () {
      var token = this.toString();

      result = result.replace(token, self.getValueForToken(token, entry));
    });

    return result;
  };

  RSS.prototype.isRelevant = function (entry, entries) {
    var tokenMap = this.getTokenMap(entry);

    if (this.options.filter) {
      if (this.options.filterLimit && (this.options.filterLimit === entries.length)) {
        return false;
      } else {
        return this.options.filter(entry, tokenMap);
      }
    } else {
      return true;
    }
  };

  RSS.prototype.getFormattedDate = function (dateString) {
    // If a custom formatting function is provided, use that.
    if (this.options.dateFormatFunction) {
      return this.options.dateFormatFunction(dateString);
    } else if (typeof moment !== 'undefined') {
      // If moment.js is available and dateFormatFunction is not overriding it,
      // use it to format the date.
      var date = moment(new Date(dateString));

      if (date.locale) {
        date = date.locale(this.options.dateLocale);
      } else {
        date = date.lang(this.options.dateLocale);
      }

      return date.format(this.options.dateFormat);
    } else {
      // If all else fails, just use the date as-is.
      return dateString;
    }
  };

  RSS.prototype.getTokenMap = function (entry) {
    if (!this.feedTokens) {
      var feed = JSON.parse(JSON.stringify(this.feed));

      delete feed.entries;
      this.feedTokens = feed;
    }

    return $.extend({
      feed:      this.feedTokens,
      url:       entry.link,
      author:    entry.author,
      date:      this.getFormattedDate(entry.publishedDate),
      title:     entry.title,
      body:      entry.content,
      shortBody: entry.contentSnippet,

      bodyPlain: (function (entry) {
        var result = entry.content
          .replace(/<script[\\r\\\s\S]*<\/script>/mgi, '')
          .replace(/<\/?[^>]+>/gi, '');

        for (var i = 0; i < RSS.htmlTags.length; i++) {
          result = result.replace(new RegExp('<' + RSS.htmlTags[i], 'gi'), '');
        }

        return result;
      })(entry),

      shortBodyPlain: entry.contentSnippet.replace(/<\/?[^>]+>/gi, ''),
      index:          $.inArray(entry, this.entries),
      totalEntries:   this.entries.length,

      teaserImage:    (function (entry) {
        try {
          return entry.content.match(/(<img.*?>)/gi)[0];
        }
        catch (e) {
          return '';
        }
      })(entry),

      teaserImageUrl: (function (entry) {
        try {
          return entry.content.match(/(<img.*?>)/gi)[0].match(/src="(.*?)"/)[1];
        }
        catch (e) {
          return '';
        }
      })(entry)
    }, this.options.tokens);
  };

  RSS.prototype.getValueForToken = function (_token, entry) {
    var tokenMap = this.getTokenMap(entry);
    var token    = _token.replace(/[\{\}]/g, '');
    var result   = tokenMap[token];

    if (typeof result !== 'undefined') {
      return ((typeof result === 'function') ? result(entry, tokenMap) : result);
    } else {
      throw new Error('Unknown token: ' + _token + ', url:' + this.url);
    }
  };

  $.fn.rss = function (url, options, callback) {
    new RSS(this, url, options, callback).render();
    return this; // Implement chaining
  };
})(jQuery);
