JavaScript: A small function to suggest tags for a page, based on things it links to w/i the MakeAPI

makeapi-suggest-tags.js

/* global define, module */
(function suggestMakeTagsRoot(){
  'use strict';

  // browser context getting dependency
  if(typeof window !== 'undefined' && !window.Make){
    var script = document.createElement('script');
    script.src = '//webmaker.org/bower/makeapi-client/src/make-api.js';
    script.onload = function(){
      suggestMakeTagsRoot();
    }
    document.head.appendChild(script);
    return;
  }

  var suggestedTags = [],
    linksToCheck = 0,
    makeapi;

  /**
   * Gets any metadata about a link from the MakeAPI 
   * and adds any tags to the `suggestedTags` array w/ a 
   * count of times its appeared
   * 
   * @param  {HTMLAreaElement|HTMLAnchorElement}   link A HTMLElement w/ a href property that has a value
   * @param  {Function} done Callback to run once async call is complete
   */
  function getLinkTags(link, done){
    makeapi.url(link.href).then(function(err, makes){
      if(err){
        console.log(err);
        if(done) done();
        return;
      }

      makes.forEach(function(make){
        make.tags.forEach(function(tag){
          // flag to indicate if tag already known
          var foundFlag = false;

          // check if current tag is known
          suggestedTags.forEach(function(tagObj){
            if(tagObj.name === tag){
              foundFlag = true;
              tagObj.count++;
            }
          });

          // if tag was not found then add it
          if(foundFlag === false){
            suggestedTags.push({
              name: tag,
              count: 1
            });
          }
        });
      });

      if(done) done();
    });
  }

  /**
   * Runs a callback passing in an Array of suggested tags.
   *
   * Returned array in the format:
   *
   * [{
   *     name: String,
   *     count: Number
   * }]
   * 
   * @param {HTMLCollection}   links Collection of all AREA elements and anchor (A) elements in a document with a value for the href attribute.
   * @param {Function} done  Callback to run once all async calls are complete and suggested tags known
   */
  function suggestMakeTags(links, done){
    Array.prototype.forEach.call(links, function(link){
      linksToCheck++;
      getLinkTags(link, function(){
        if(--linksToCheck === 0){
          done(suggestedTags);
        }
      });
    });
  }

  // AMD context
  if(typeof define !== 'undefined'){
    // somehow need to get/require makeapi here too...
    define(['makeapi-client'], function(makeapiClient){
      makeapi = makeapiClient({
        apiURL: 'https://makeapi.webmaker.org'
      });
      return suggestMakeTags;
    });
  }

  // Node.js context
  else if(typeof module !== 'undefined' && module.exports){
    makeapi = require('makeapi-client')({
      apiURL: 'https://makeapi.webmaker.org'
    });
    module.exports = suggestMakeTags;
  }

  // browser context
  else if(typeof window !== 'undefined' && window.Make){
    makeapi = new window.Make({
      apiURL: 'https://makeapi.webmaker.org'
    });
    window.suggestMakeTags = suggestMakeTags;
  }
}());