docbrown/app/assets/javascripts/initializers/initializeFetchFollowedArticles.js.erb

function initializeFetchFollowedArticles() {
  if ( document.getElementById("featured-story-marker") && checkUserLoggedIn() ) {
    algoliaFollowedArticles();
  }
}
  
function insertArticle(article,parent,insertPlace) {
  if (article){
    var newItem = document.createElement("DIV");
    newItem.innerHTML = buildArticleHTML(article)
    parent.insertBefore(newItem, insertPlace);
    initializeReadingListIcons();
  }
}

function insertInitialArticles(user) {
  var el = document.getElementById("home-articles-object")
  if (!el) {return}
  var articlesJSON = JSON.parse(el.dataset.articles)
  el.outerHTML = "";
  var insertPlace = document.getElementById("article-index-hidden-div");
  if (insertPlace) {
    var parent = insertPlace.parentNode;
      articlesJSON.forEach(function(article){
      var containsTag = findOne(user.followed_tag_names, article.cached_tag_list_array)
      var containsUserID = findOne([article.user_id], user.followed_user_ids)
      if ( (containsTag || containsUserID) && !document.getElementById("article-link-"+article.id) ) {
        insertArticle(article,parent,insertPlace);
      }
    });
  }
}

function algoliaFollowedArticles(){
    var user = userData();
    if (user && user.followed_tag_names && user.followed_tag_names.length > 0) {
      insertInitialArticles(user)
      var followedUsersArray = [];
      if (user.followed_user_ids){
        followedUsersArray = user.followed_user_ids.map(function(id){return 'user_'+id});
      }
      var publicSearchKey = '<%= ALGOLIASEARCH_PUBLIC_SEARCH_ONLY_KEY %>'
      var client = algoliasearch('<%= ApplicationConfig["ALGOLIASEARCH_APPLICATION_ID"] %>', publicSearchKey);
      var index = client.initIndex('ordered_articles_<%= Rails.env %>');
      
      var searchObj = {
          hitsPerPage: 20,
          page: "0",
          attributesToHighlight: [],
          tagFilters: [user.followed_tag_names.concat(followedUsersArray)],
      }
      
      var homeEl = document.getElementById("index-container");
      if (homeEl.dataset.feed === "base-feed") {
        articlesIndex = client.initIndex('ordered_articles_<%= Rails.env %>');
      } else if (homeEl.dataset.feed === "latest") {
        articlesIndex = client.initIndex('ordered_articles_by_published_at_<%= Rails.env %>');
      } else {
        searchObj["filters"] = ('published_at_int > ' + homeEl.dataset.articlesSince);
        articlesIndex = client.initIndex('ordered_articles_by_positive_reactions_count_<%= Rails.env %>');
      }
      articlesIndex.search("*", searchObj)
      .then(function searchDone(content) {
        var insertPlace = document.getElementById("article-index-hidden-div");
        if (insertPlace) {
          var parent = insertPlace.parentNode;
          content.hits.forEach(function(article){
            if ( !document.getElementById("article-link-"+article.id) ) {
              insertArticle(article,parent,insertPlace);
            }
          });
        }
        var el = document.getElementById("home-articles-object")
        if (el){el.outerHTML = ''}
      });
    }
}

function findOne(haystack, arr) {
    return arr.some(function (v) {
        return haystack.indexOf(v) >= 0;
    });
};