03같은 태그를 다시 넣으면 기존 칩이 깜빡이는 입력

<main class="stage">
<div class="td is-demo" id="td">
  <div class="td__row" id="tdRow">
    <input type="text" class="td__input" id="tdInput" aria-label="태그 입력, 이미 있으면 새로 만들지 않고 그 칩이 빛난다" placeholder="태그 입력">
    <button type="button" class="td__add" id="tdAdd" aria-label="태그 추가">+</button>
  </div>
  <p class="td__meta">태그 <b id="tdCount">0</b>개<span class="td__dup" id="tdDup" hidden> · 이미 있음</span></p>
  <p class="td__sr" role="status" aria-live="polite" id="tdLive"></p>
</div>
</main>

@use "../../../../site/static/demo-tokens" as *;

// 계산 겹: findDup() 이 입력 문자열을 정규화(trim+lowercase)해 기존 칩 전부와 견준다.
// 같은 게 있으면 새 칩을 만들지 않고 그 칩에 td__chip--merge 를 다시 걸어(reflow) 감쇠 펄스 +
// 링 글로우를 재생한다 — 병합은 "새로 안 만든다"이지 두 칩을 하나로 접는 연출이 아니다.
@include stage($stage-orange);

.td { width: min(100%, 300px); display: flex; flex-direction: column; gap: $sp-2; }
.td__row {
  display: flex; flex-wrap: wrap; align-items: center; gap: $sp-2;
  background: rgba($subject-cream, .14); border: 1px solid rgba($subject-cream, .4);
  border-radius: $r-control; padding: $sp-2 $sp-3;
}
.td__input {
  flex: 1 1 auto; min-width: 0; border: none; background: transparent; color: $subject-cream;
  font-size: 12px; outline: none;
}
.td__input::placeholder { color: rgba($subject-cream, .7); }
.td__add {
  flex: 0 0 auto; width: 26px; height: 26px; border: none; border-radius: 50%;
  background: $subject-cream; color: $subject-ink; font-size: 15px; line-height: 1; cursor: pointer;
  display: grid; place-items: center; transition: transform $dur-instant $ease-out;
}
.td__add:active { transform: scale(.88); }
.td__add:focus-visible { outline: 2px solid $subject-ink; outline-offset: 2px; }

.td__chip {
  display: inline-flex; align-items: center; gap: $sp-1; height: 24px; padding: 0 $sp-1 0 $sp-3;
  background: $subject-cream; color: $subject-ink; border-radius: $r-pill;
  font-size: 12px; font-weight: 700; white-space: nowrap;
  transform: scale(1); opacity: 1; transition: transform $dur-quick $ease-pop, opacity $dur-quick $ease-out;
}
.td__chip--enter { transform: scale(.6); opacity: 0; }
.td__chip--merge { animation: tdMerge $dur-enter $ease-spring 1; }
.td__chipX {
  width: 16px; height: 16px; border: none; border-radius: 50%; background: rgba($subject-ink, .16);
  color: $subject-ink; font-size: 11px; line-height: 1; cursor: pointer; display: grid; place-items: center;
}
.td__chipX:focus-visible { outline: 2px solid $subject-ink; outline-offset: 2px; }

.td__meta { margin: 0; font-size: 11px; color: rgba($subject-cream, .85); }
.td__meta b { color: $subject-cream; font-weight: 700; }
.td__dup { color: $subject-cream; font-weight: 700; }
.td__sr {
  position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); margin: -1px; padding: 0; border: 0;
}

// 감쇠 스프링 펄스 + 링 글로우: 크기가 1→1.16→0.95→1.05→1 로 오버슈트하며 그림자 링이 함께 사그라든다
@keyframes tdMerge {
  0%   { transform: scale(1);    box-shadow: 0 0 0 0 rgba($subject-blue-deep, 0); }
  14%  { transform: scale(1.16); box-shadow: 0 0 0 6px rgba($subject-blue-deep, .45); }
  32%  { transform: scale(.95);  box-shadow: 0 0 0 3px rgba($subject-blue-deep, .3); }
  50%  { transform: scale(1.05); box-shadow: 0 0 0 5px rgba($subject-blue-deep, .18); }
  70%  { transform: scale(.99);  box-shadow: 0 0 0 2px rgba($subject-blue-deep, .1); }
  100% { transform: scale(1);    box-shadow: 0 0 0 0 rgba($subject-blue-deep, 0); }
}

@media (max-width: 340px) {
  .td { width: 100%; }
  .td__row { padding: $sp-2; }
}

@media (prefers-reduced-motion: reduce) {
  .td__chip { transition: none; }
  .td__chip--merge { animation: none; }
  .td__add { transition: none; }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.td {
  width: min(100%, 300px);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.td__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  background: rgba(255, 247, 230, 0.14);
  border: 1px solid rgba(255, 247, 230, 0.4);
  border-radius: 12px;
  padding: 8px 12px;
}

.td__input {
  flex: 1 1 auto;
  min-width: 0;
  border: none;
  background: transparent;
  color: #fff7e6;
  font-size: 12px;
  outline: none;
}

.td__input::placeholder {
  color: rgba(255, 247, 230, 0.7);
}

.td__add {
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  border: none;
  border-radius: 50%;
  background: #fff7e6;
  color: #17141a;
  font-size: 15px;
  line-height: 1;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: transform 140ms ease-out;
}

.td__add:active {
  transform: scale(0.88);
}

.td__add:focus-visible {
  outline: 2px solid #17141a;
  outline-offset: 2px;
}

.td__chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  height: 24px;
  padding: 0 4px 0 12px;
  background: #fff7e6;
  color: #17141a;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
  white-space: nowrap;
  transform: scale(1);
  opacity: 1;
  transition: transform 220ms cubic-bezier(0.2, 1.4, 0.4, 1), opacity 220ms ease-out;
}

.td__chip--enter {
  transform: scale(0.6);
  opacity: 0;
}

.td__chip--merge {
  animation: tdMerge 600ms cubic-bezier(0.2, 0.8, 0.2, 1) 1;
}

.td__chipX {
  width: 16px;
  height: 16px;
  border: none;
  border-radius: 50%;
  background: rgba(23, 20, 26, 0.16);
  color: #17141a;
  font-size: 11px;
  line-height: 1;
  cursor: pointer;
  display: grid;
  place-items: center;
}

.td__chipX:focus-visible {
  outline: 2px solid #17141a;
  outline-offset: 2px;
}

.td__meta {
  margin: 0;
  font-size: 11px;
  color: rgba(255, 247, 230, 0.85);
}

.td__meta b {
  color: #fff7e6;
  font-weight: 700;
}

.td__dup {
  color: #fff7e6;
  font-weight: 700;
}

.td__sr {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  margin: -1px;
  padding: 0;
  border: 0;
}

@keyframes tdMerge {
  0% {
    transform: scale(1);
    box-shadow: 0 0 0 0 rgba(10, 79, 232, 0);
  }
  14% {
    transform: scale(1.16);
    box-shadow: 0 0 0 6px rgba(10, 79, 232, 0.45);
  }
  32% {
    transform: scale(0.95);
    box-shadow: 0 0 0 3px rgba(10, 79, 232, 0.3);
  }
  50% {
    transform: scale(1.05);
    box-shadow: 0 0 0 5px rgba(10, 79, 232, 0.18);
  }
  70% {
    transform: scale(0.99);
    box-shadow: 0 0 0 2px rgba(10, 79, 232, 0.1);
  }
  100% {
    transform: scale(1);
    box-shadow: 0 0 0 0 rgba(10, 79, 232, 0);
  }
}
@media (max-width: 340px) {
  .td {
    width: 100%;
  }
  .td__row {
    padding: 8px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .td__chip {
    transition: none;
  }
  .td__chip--merge {
    animation: none;
  }
  .td__add {
    transition: none;
  }
}

(function () {
  var WORDS = ['아이디어', '초안', '아이디어', '검토'];
  var ADD_MS = 620, PAUSE_MS = 900;
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  var root = document.getElementById('td');
  var row = document.getElementById('tdRow');
  var input = document.getElementById('tdInput');
  var addBtn = document.getElementById('tdAdd');
  var countEl = document.getElementById('tdCount');
  var dupEl = document.getElementById('tdDup');
  var live = document.getElementById('tdLive');
  var seq = 0;

  function norm(text) { return text.trim().toLowerCase(); }
  function chips() { return Array.prototype.slice.call(row.querySelectorAll('.td__chip')); }
  function render() { countEl.textContent = chips().length; }
  function human() { if (root.classList.contains('is-demo')) root.classList.remove('is-demo'); }

  function findDup(text) {
    // 계산 겹: 정규화한 문자열을 기존 칩 전부와 견줘 같은 것을 찾는다 — 대소문자·앞뒤 공백은 다르게 치지 않는다
    var key = norm(text);
    var list = chips();
    for (var i = 0; i < list.length; i++) {
      if (norm(list[i].dataset.text) === key) return list[i];
    }
    return null;
  }

  function merge(chip) {
    // 계산 겹: 새 칩을 만들지 않고 이미 있는 칩에 감쇠 스프링 펄스를 다시 건다(reflow 로 재생 보장)
    chip.classList.remove('td__chip--merge');
    void chip.offsetWidth;
    chip.classList.add('td__chip--merge');
    dupEl.hidden = false;
    live.textContent = chip.dataset.text + ' 은 이미 있다';
    if (reduce) render();
  }

  function add(text) {
    if (!text) return;
    var dup = findDup(text);
    if (dup) { merge(dup); return; }
    dupEl.hidden = true;
    seq++;
    var chip = document.createElement('span');
    chip.className = 'td__chip td__chip--enter';
    chip.id = 'tdChip' + seq;
    chip.dataset.text = text;
    chip.innerHTML = '<span class="td__chipText"></span><button type="button" class="td__chipX">×</button>';
    chip.querySelector('.td__chipText').textContent = text;
    chip.querySelector('.td__chipX').setAttribute('aria-label', '태그 삭제: ' + text);
    chip.querySelector('.td__chipX').addEventListener('click', function () { human(); chip.remove(); render(); });
    row.insertBefore(chip, input);
    requestAnimationFrame(function () { chip.classList.remove('td__chip--enter'); });
    render();
    live.textContent = text + ' 추가 · 태그 ' + chips().length + '개';
  }

  addBtn.addEventListener('click', function () { human(); add(input.value.trim()); input.value = ''; });
  input.addEventListener('keydown', function (e) {
    if (e.key === 'Enter' && input.value.trim()) { human(); add(input.value.trim()); input.value = ''; }
  });

  var timer = 0;
  function schedule(fn, ms) { timer = window.setTimeout(fn, ms); }

  function loop(i) {
    if (!root.classList.contains('is-demo')) return;
    if (i < WORDS.length) {
      add(WORDS[i]);
      schedule(function () { loop(i + 1); }, ADD_MS);
    } else {
      chips().forEach(function (c) { c.remove(); });
      dupEl.hidden = true;
      render();
      schedule(function () { loop(0); }, PAUSE_MS);
    }
  }

  render();
  if (!reduce) {
    schedule(function () { loop(0); }, 260);
  } else {
    root.classList.remove('is-demo');
  }
})();

// TagDuplicateHighlightMerge — vanilla 판(run/397/demo/03-tag-input-duplicate-highlight-merge/index.html) 의 React 포트.
// findDup() 이 정규화(trim+lowercase)해 기존 칩과 견준다 — 같은 게 있으면 새로 안 만들고
// 그 칩의 merge key 를 올려 재생(리마운트)시켜 감쇠 펄스+글로우를 다시 건다.
import { useEffect, useRef, useState } from "react";
import styles from "./TagDuplicateHighlightMerge.module.scss";

type Box<T> = { current: T };
type ChangeEvt = { target: { value: string } };
type KeyEvt = { key: string };

const WORDS = ["아이디어", "초안", "아이디어", "검토"];
const ADD_MS = 620, PAUSE_MS = 900;

type Chip = { id: number; text: string; entering: boolean; mergeKey: number };

function norm(text: string): string {
  return text.trim().toLowerCase();
}

export default function TagDuplicateHighlightMerge() {
  const timerRef = useRef(0) as unknown as Box<number>;
  const seqRef = useRef(1) as unknown as Box<number>;
  const mergeSeqRef = useRef(0) as unknown as Box<number>;
  const isDemoRef = useRef(true) as unknown as Box<boolean>;
  const chipsRef = useRef<Chip[]>([]) as unknown as Box<Chip[]>;

  const [chips, setChips] = useState<Chip[]>([]);
  const [draft, setDraft] = useState("");
  const [dup, setDup] = useState(false);
  const [isDemo, setIsDemo] = useState(true);
  const [live, setLive] = useState("");

  useEffect(() => { chipsRef.current = chips; }, [chips]);

  function human() {
    if (isDemoRef.current) { isDemoRef.current = false; setIsDemo(false); }
  }

  function add(text: string) {
    if (!text) return;
    const key = norm(text);
    const found = chipsRef.current.find((c) => norm(c.text) === key);
    if (found) {
      // 계산 겹: 새 칩을 만들지 않고 있는 칩의 mergeKey 만 올려 펄스를 다시 재생한다
      mergeSeqRef.current++;
      const mk = mergeSeqRef.current;
      setChips((cs) => cs.map((c) => (c.id === found.id ? { ...c, mergeKey: mk } : c)));
      setDup(true);
      setLive(found.text + " 은 이미 있다");
      return;
    }
    setDup(false);
    const id = seqRef.current++;
    setChips((cs) => [...cs, { id, text, entering: true, mergeKey: 0 }]);
    setLive(text + " 추가 · 태그 " + (chipsRef.current.length + 1) + "개");
    window.setTimeout(() => {
      setChips((cs) => cs.map((c) => (c.id === id ? { ...c, entering: false } : c)));
    }, 20);
  }

  function removeChip(id: number) {
    human();
    setChips((cs) => cs.filter((c) => c.id !== id));
  }

  useEffect(() => {
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;

    function loop(i: number) {
      if (!isDemoRef.current) return;
      if (i < WORDS.length) {
        add(WORDS[i]);
        timerRef.current = window.setTimeout(() => loop(i + 1), ADD_MS);
      } else {
        setChips([]);
        setDup(false);
        timerRef.current = window.setTimeout(() => loop(0), PAUSE_MS);
      }
    }

    if (!reduce) {
      timerRef.current = window.setTimeout(() => loop(0), 260);
    } else {
      isDemoRef.current = false;
      setIsDemo(false);
    }
    return () => window.clearTimeout(timerRef.current);
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  function onAdd() { human(); add(draft.trim()); setDraft(""); }
  function onInput(e: ChangeEvt) { setDraft(e.target.value); }
  function onKeyDown(e: KeyEvt) {
    if (e.key === "Enter" && draft.trim()) { human(); add(draft.trim()); setDraft(""); }
  }

  return (
    <main className={styles.stage}>
      <div className={styles.td + " " + (isDemo ? styles.isDemo : "")}>
        <div className={styles.row}>
          {chips.map((c) => (
            <span
              key={c.id + "-" + c.mergeKey}
              className={styles.chip + (c.entering ? " " + styles.chipEnter : "") + (c.mergeKey ? " " + styles.chipMerge : "")}
            >
              <span>{c.text}</span>
              <button type="button" className={styles.chipX} aria-label={"태그 삭제: " + c.text} onClick={() => removeChip(c.id)}>×</button>
            </span>
          ))}
          <input
            type="text" className={styles.input} aria-label="태그 입력, 이미 있으면 새로 만들지 않고 그 칩이 빛난다"
            placeholder="태그 입력" value={draft} onChange={onInput} onKeyDown={onKeyDown}
          />
          <button type="button" className={styles.add} aria-label="태그 추가" onClick={onAdd}>+</button>
        </div>
        <p className={styles.meta}>
          태그 <b>{chips.length}</b>개
          {dup ? <span className={styles.dup}> · 이미 있음</span> : null}
        </p>
        <p className={styles.sr} role="status">{live}</p>
      </div>
    </main>
  );
}