// ==UserScript==
// @name        Study.com Quiz Answers
// @namespace   Violentmonkey Scripts
// @match       *://*.study.com/*
// @include     https://study.com/*
// @grant       none
// @version     1.1
// @author      Jonah Lawrence
// @description Highlights correct answers with a green background on Study.com quizes and exams
// @downloadURL none
// ==/UserScript==

/* jshint esversion: 6 */

(function () {
  const interval = setInterval(function () {
    const container = document.querySelector("#practice-exam-container");
    // check if practice-exam-container element exists (only on exam pages)
    if (container) {
      const controller = angular.element(container).controller();
      if (controller) {
        // get questions
        const questions = controller.questionByQuestionInstanceId;
        // highlight the answer to each question
        Object.values(questions).forEach(function (x) {
          const correctAnswer = document.querySelector(`li[ng-class*="${x.correctQuizQuestionOptionId}"]`);
          if (correctAnswer) {
            correctAnswer.style.background = "#c5ff81";
            correctAnswer.style.borderRadius = "2px";
            correctAnswer.style.boxShadow = "0 0 0 6px #c5ff81";
            // no need to keep checking
            clearInterval(interval);
          }
        });
      }
    }
    else {
      // add styling for showing quiz answers
      const styles = 'label[data-correct="true"] { background: #c5ff81; box-shadow: 0 0 0 14px #c5ff81; }';
      document.getElementsByTagName("head")[0].insertAdjacentHTML("beforeend", `<style>${styles}</style>`);
      // disable interval since this is not an exam
      clearInterval(interval);
    }
  }, 500);
})();