import { replaceSpan } from 'discourse/lib/category-hashtags';

const validCategoryHashtags = {};
const checkedCategoryHashtags = [];
const testedKey = 'tested';
const testedClass = `hashtag-${testedKey}`;

function updateFound($hashtags, categorySlugs) {
  Ember.run.schedule('afterRender', () => {
    $hashtags.each((index, hashtag) => {
      const categorySlug = categorySlugs[index];
      const link = validCategoryHashtags[categorySlug];
      const $hashtag = $(hashtag);

      if (link) {
        replaceSpan($hashtag, categorySlug, link);
      } else if (checkedCategoryHashtags.indexOf(categorySlug) !== -1) {
        $hashtag.addClass(testedClass);
      }
    });
  });
};

export function linkSeenCategoryHashtags($elem) {
  const $hashtags = $(`span.hashtag:not(.${testedClass})`, $elem);
  const unseen = [];

  if ($hashtags.length) {
    const categorySlugs = $hashtags.map((_, hashtag) => $(hashtag).text().substr(1));
    if (categorySlugs.length) {
      _.uniq(categorySlugs).forEach((categorySlug) => {
        if (checkedCategoryHashtags.indexOf(categorySlug) === -1) {
          unseen.push(categorySlug);
        }
      });
    }
    updateFound($hashtags, categorySlugs);
  }

  return unseen;
};

export function fetchUnseenCategoryHashtags(categorySlugs) {
  return Discourse.ajax("/category_hashtags/check", { data: { category_slugs: categorySlugs } })
    .then((response) => {
      response.valid.forEach((category) => {
        validCategoryHashtags[category.slug] = category.url;
      });
      checkedCategoryHashtags.push.apply(checkedCategoryHashtags, categorySlugs);
    });
}
