quizlet_live.js

try {
  async function getSetId(pin) {
    const res = await fetch(`https://quizlet.com/webapi/3.8/multiplayer/game-instance?gameCode=${pin}`);
    const json = await res.json();
    if(json.error) throw new Error(json.error.message);
    return json.gameInstance.itemId;
  }
  async function getSetData(setId) {
    const res = await fetch(`https://quizlet.com/${setId}`);
    const text = await res.text();
    const data = text.match(/\\"termIdToTermsMap\\":{.+?{.+?\\"termSort\\":/gi)?.[0];
    if(!data) throw new Error("Failed to parse set data.");
    const parsed = JSON.parse(data.slice(21, -14).replaceAll(`\\"`,`"`));
    return [Object.fromEntries(Object.values(parsed).map(({word, definition}) => [word, definition])), Object.fromEntries(Object.values(parsed).map(({word, definition}) => [definition, word]))];
  }
  function getActiveQuestion() {
    try {
      const question = document.querySelector(".StudentPrompt-text").textContent;
      const answers = Array.from(document.querySelectorAll(".StudentAnswerOption-text"));
      return [question, answers];
    }catch {}
    return [null, null];
  }
  (async() => {
    const pin = prompt("Enter PIN, like: XXX-XXX", "").match(/[0-9a-zA-Z]/g).join("");
    if(pin.length !== 6) throw new Error("Pin must be 6 characters in length.");
    const setId = await getSetId(pin);
    const [term2Def, def2Term] = await getSetData(setId);
    setInterval(async function() {
      const [question, choices] = getActiveQuestion();
      if(!question || !choices) return;
      if(question in term2Def) {
        choices.forEach((choice) => {
          if(choice.textContent === term2Def[question]) choice.style.fontWeight = "bolder";
        });
      }else if(question in def2Term) {
        choices.forEach((choice) => {
          if(choice.textContent === def2Term[question]) choice.style.fontWeight = "bolder";
        });
      }else {
        choices.forEach((choice) => {
          choice.style.fontWeight = "normal";
        });
      }
    }, 0);
  })();
}catch(err) {
  alert(err);
}