lib/classes/URLEmbedProvider.js

'use strict';

/**
* Converts a pattern of URLs into markup
* @interface
*/
class URLEmbedProvider {
  /**
  * @param {Array<RegExp>} urlPatterns - array of regular expressions that this provider will match
  */
  constructor (urlPatterns) {
    /**
    * Array of regular expressions that this provider will match
    * @type {Array<RegExp>}
    */
    if (urlPatterns) this.urlPatterns = urlPatterns;
  }

  /**
  * Determines if a given URL matches this provider
  * @param {String} embedURL - URL to embed
  * @return {boolean}
  */
  isMatch (embedURL) {
    let matches = false;
    for (let idx = 0; idx < this.urlPatterns.length; idx++) {
      if (embedURL.match(this.urlPatterns[idx])) {
        matches = true;
        idx = this.urlPatterns.length;
      }
    }
    return matches;
  }

  /**
  * Resolves options.embedURL to an embed and passes it to callback.
  * @param {Embed} embed - Embed object
  * @param {function(error: Error, data: Object)} callback - callback to invoke after resolving embed
  */
  getEmbed (embed, callback) {
    try {
      this.filterData(embed.data);
      callback(embed);
    } catch (error) {
      embed.error = error;
      embed.data = {
        html: this.errorMarkup(embed)
      };
      callback(embed);
    }
  }

  /**
  * Can be overridden/replaced to modify a specific provider's data before it is passed to the client callback.<br />
  * @param {{html: String}} data - Data object containing embed html
  */
  filterData (data) {}

  /**
  * Returns markup if an error occurs resolving the embed
  * @param {Embed} embed - Embed object
  */
  errorMarkup (embed) {
    return '<a href="' + embed.embedURL + '">' + embed.embedURL + '</a>';
  }

  /**
  * Stub method caled by EmbedEngine. Can be overridden.
  * @param {Object} engineOptions
  */
  configure (engineOptions) {

  }
}

module.exports = URLEmbedProvider;