overleaf/services/web/frontend/js/ide/history/directives/infiniteScroll.js

/* eslint-disable
    max-len,
*/
// TODO: This file was created by bulk-decaffeinate.
// Fix any style issues and re-enable lint.
/*
 * decaffeinate suggestions:
 * DS102: Remove unnecessary code created because of implicit returns
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
import App from '../../../base'

export default App.directive('infiniteScroll', () => ({
  link(scope, element, attrs, ctrl) {
    const innerElement = element.find('.infinite-scroll-inner')
    element.css({ 'overflow-y': 'auto' })

    const atEndOfListView = function () {
      if (attrs.infiniteScrollUpwards != null) {
        return atTopOfListView()
      } else {
        return atBottomOfListView()
      }
    }

    const atTopOfListView = () => element.scrollTop() < 30

    const atBottomOfListView = () =>
      element.scrollTop() + element.height() >= innerElement.height() - 30

    const listShorterThanContainer = () =>
      element.height() > innerElement.height()

    function loadUntilFull() {
      if (
        (listShorterThanContainer() || atEndOfListView()) &&
        !scope.$eval(attrs.infiniteScrollDisabled)
      ) {
        const promise = scope.$eval(attrs.infiniteScroll)
        return promise.then(() => setTimeout(() => loadUntilFull(), 0))
      }
    }

    element.on('scroll', event => loadUntilFull())

    return scope.$watch(attrs.infiniteScrollInitialize, function (value) {
      if (value) {
        return loadUntilFull()
      }
    })
  },
}))