const faculties = document.getElementsByClassName("faculty");
const alphabets = document.querySelectorAll("#alphabet>ul>a>li");
const indexes = document.querySelectorAll("#faculties>.index");
const arr = [...faculties];
const result = sortFaculties(arr);

if (result) {
  result.forEach((el) => {
    // console.log(el);
    for (let i = 0; i < alphabets.length; i++) {
      if (el.letter.toUpperCase() === alphabets[i].innerText.trim()) {
        alphabets[i].classList.remove("hidden");
        break;
      }
    }
    for (let i = 0; i < indexes.length; i++) {
      if (el.letter.toUpperCase() === indexes[i].children[0].innerText.trim()) {
        indexes[i].classList.remove("hidden");
        indexes[i].classList.add("grid");
        indexes[i].children[0].classList.remove("hidden");
        break;
      }
    }
    let index = document.getElementById(el.letter.toUpperCase());

    el.data.forEach((e) => {
      e.classList.remove("hidden");
      index.append(e);
    });
  });
}

function sortFaculties(arr, empty) {
  if (!String.prototype.localeCompare) return null;
  const letters = "*abcdefghjklmnopqrstwxyz".split("");
  const zh = "阿八嚓哒妸发旮哈讥咔垃妈拏噢妑七呥扨它穵夕丫帀".split("");
  const segs = [];
  var curr;

  letters.forEach((el, i) => {
    curr = { letter: el, data: [] };
    arr.forEach((e) => {
      // console.log(e);
      let e1 = e.innerText.replace(/^沈/, "审").replace(/^曾/, "增");
      // console.log(e1);
      if (
        (!zh[i - 1] || zh[i - 1].localeCompare(e1, "zh-CN") <= 0) &&
        e1.localeCompare(zh[i], "zh-CN") == -1
      ) {
        curr.data.push(e);
      }
    });
    if (empty || curr.data.length) {
      segs.push(curr);
      curr.data.sort(function (a, b) {
        let a1 = a.innerText.replace(/^沈/, "审").replace(/^曾/, "增");
        let b1 = b.innerText.replace(/^沈/, "审").replace(/^曾/, "增");
        return a1.localeCompare(b1, "zh-CN");
      });
    }
  });
  return segs;
}