08Mobile sheet morph — the dropdown reshaping into a bottom sheet under a media query

<main class="stage">
<div class="ms" id="ms">
  <p class="ms__hint">When the screen is narrow, matchMedia rearranges the same list into a bottom sheet.</p>
  <div class="ms__field">
    <input class="ms__input" type="text" value="pineapple" readonly aria-label="Search fruit">
  </div>
  <div class="ms__sheet" id="msSheet">
    <span class="ms__handle" aria-hidden="true"></span>
    <ul class="ms__list" id="msList" role="listbox" aria-label="Suggestion list"></ul>
  </div>
</div>
</main>

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

$duration: $dur-base;
$easing: $ease-out;
$color: $subject-blue-deep;

@include stage($stage-paper);

.ms {
  width: 100%;
  max-width: 280px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: $sp-2;
}

.ms__hint {
  margin: 0;
  padding: 0 $sp-1;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba($subject-ink, .72);
}

.ms__field {
  background: $subject-cream;
  border-radius: $r-control;
  padding: $sp-2 $sp-3;
  box-shadow: $shadow-press;
}

.ms__input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  font-weight: 500;
  font-size: 13px;
  color: $subject-ink;
}

.ms__sheet {
  background: $subject-cream;
  border-radius: $r-card;
  box-shadow: $shadow-press;
  padding: $sp-1;
}

.ms__handle {
  display: none;
  width: 32px;
  height: 4px;
  margin: 0 auto $sp-1;
  border-radius: $r-xs;
  background: rgba($subject-ink, .24);
}

.ms__list {
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-y: hidden;
  max-height: calc(28px + 64px * var(--kb, 0));
}

.ms__item {
  padding: $sp-1 $sp-2;
  border-radius: $r-sm;
  font-weight: 500;
  font-size: 12px;
  color: $subject-ink;
}

.is-sheet .ms {
  position: relative;
  height: 130px;
}

.is-sheet .ms__hint {
  display: none;
}

.is-sheet .ms__sheet {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
  box-shadow: $shadow-raised;
}

.is-sheet .ms__handle {
  display: block;
}

@media (max-width: 340px) {
  .ms { max-width: 220px; }
  .ms__input { font-size: 12px; }
}

@media (prefers-reduced-motion: reduce) {
  .ms__list {
    transition: none;
  }
}

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

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

.ms {
  width: 100%;
  max-width: 280px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.ms__hint {
  margin: 0;
  padding: 0 4px;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba(23, 20, 26, 0.72);
}

.ms__field {
  background: #fff7e6;
  border-radius: 12px;
  padding: 8px 12px;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
}

.ms__input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  font-weight: 500;
  font-size: 13px;
  color: #17141a;
}

.ms__sheet {
  background: #fff7e6;
  border-radius: 16px;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
  padding: 4px;
}

.ms__handle {
  display: none;
  width: 32px;
  height: 4px;
  margin: 0 auto 4px;
  border-radius: 4px;
  background: rgba(23, 20, 26, 0.24);
}

.ms__list {
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-y: hidden;
  max-height: calc(28px + 64px * var(--kb, 0));
}

.ms__item {
  padding: 4px 8px;
  border-radius: 8px;
  font-weight: 500;
  font-size: 12px;
  color: #17141a;
}

.is-sheet .ms {
  position: relative;
  height: 130px;
}

.is-sheet .ms__hint {
  display: none;
}

.is-sheet .ms__sheet {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}

.is-sheet .ms__handle {
  display: block;
}

@media (max-width: 340px) {
  .ms {
    max-width: 220px;
  }
  .ms__input {
    font-size: 12px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .ms__list {
    transition: none;
  }
}

// 모바일 시트 변신(08) — matchMedia(340px) 로 좁은 화면을 감지해 같은 목록 DOM 을
// 인라인 드롭다운/바텀시트로 재배치한다(root 클래스 토글, 진짜 API). 가상 키보드는
// 정적 캡처에서 실제로 열리지 않으니, window.visualViewport 로 실측한 높이(있으면
// innerHeight 와의 차)를 기본값으로 삼고 그 위에 스크립트로 만든 0→1 목표값을
// lerp(관성 보간)로 뒤쫓게 해 "키보드가 밀어 올리는" 느낌을 재현한다 — 목록의
// max-height 를 --kb 변수로 calc() 에 물린다.
(function () {
  var root = document.getElementById('ms');
  var sheet = document.getElementById('msSheet');
  var list = document.getElementById('msList');
  if (!root || !sheet || !list) return;

  var WORDS = ['pineapple', 'banana', 'grapefruit', 'cherry', 'watermelon', 'mango'];
  list.innerHTML = WORDS.map(function (w) {
    return '<li class="ms__item" role="option">' + w + '</li>';
  }).join('');

  var mq = window.matchMedia('(max-width: 340px)');
  function applyLayout(m) { root.classList.toggle('is-sheet', m.matches); }
  applyLayout(mq);
  if (mq.addEventListener) mq.addEventListener('change', applyLayout);
  else if (mq.addListener) mq.addListener(applyLayout);

  var vv = window.visualViewport;
  function realKbPx() {
    if (!vv) return 0;
    return Math.max(0, window.innerHeight - vv.height);
  }
  // 정적 캡처에서는 realKbPx() 가 대부분 0 이라 화면에 보이는 열림·닫힘은
  // 아래 목표값 lerp 가 만든다 — 실제 기기에서는 이 값이 목표값을 대신한다.
  var current = 0, target = 0;
  var lastFlip = 0;

  function tick(now) {
    if (now - lastFlip > 900) {
      target = target === 0 ? 1 : 0;
      lastFlip = now;
    }
    current += (target - current) * 0.12;
    sheet.style.setProperty('--kb', current.toFixed(4));
    if (playing) requestAnimationFrame(tick);
  }

  var playing = true;
  function stop() {
    playing = false;
    sheet.style.setProperty('--kb', '0');
  }
  root.addEventListener('pointerdown', stop);

  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  if (reduce) {
    sheet.style.setProperty('--kb', String(realKbPx() > 0 ? 1 : 0.4));
  } else {
    requestAnimationFrame(function (t) { lastFlip = t; tick(t); });
  }
})();

// SearchAutocompleteMobileSheetMorph — vanilla 판(run/335/demo/08-search-autocomplete-mobile-sheet-morph/index.html)
// 의 React 포트. matchMedia(340px) 로 좁은 화면을 감지해 같은 목록 DOM 을 인라인
// 드롭다운/바텀시트로 재배치한다(root 클래스 토글, 진짜 API). visualViewport 로
// 실측한 키보드 높이를 기본값으로 삼고, 그 위에 스크립트가 만든 0→1 목표값을
// lerp(관성 보간)로 뒤쫓게 해 "키보드가 밀어 올리는" 느낌을 재현한다 — 목록의
// max-height 를 --kb 변수로 calc() 에 물린다.
import { useEffect, useRef } from "react";
import styles from "./SearchAutocompleteMobileSheetMorph.module.scss";

export type SearchAutocompleteMobileSheetMorphProps = {
  duration?: string;
  easing?: string;
  color?: string;
};

const HINT = "화면이 좁으면 matchMedia 가 같은 목록을 바텀시트로 다시 배치합니다";
const ARIA_LABEL = "과일 검색";
const LIST_LABEL = "제안 목록";

const WORDS = ["파인애플", "바나나", "자몽", "체리", "수박", "망고"];

export default function SearchAutocompleteMobileSheetMorph({
  duration = "300ms",
  easing = "ease-out",
  color = "#0a4fe8"
}: SearchAutocompleteMobileSheetMorphProps) {
  const rootRef = useRef<HTMLDivElement | null>(null);
  const sheetRef = useRef<HTMLDivElement | null>(null);
  const listRef = useRef<HTMLUListElement | null>(null);

  useEffect(() => {
    const root = rootRef.current;
    const sheet = sheetRef.current;
    const list = listRef.current;
    if (!root || !sheet || !list) return;

    list.innerHTML = WORDS.map((w) => '<li class="' + styles.item + '" role="option">' + w + "</li>").join("");

    const mq = window.matchMedia("(max-width: 340px)");
    function applyLayout(m: MediaQueryList | MediaQueryListEvent): void {
      root!.classList.toggle(styles.isSheet, m.matches);
    }
    applyLayout(mq);
    const mqAny = mq as MediaQueryList & { addListener?: (cb: (m: MediaQueryListEvent) => void) => void; removeListener?: (cb: (m: MediaQueryListEvent) => void) => void };
    if (mq.addEventListener) mq.addEventListener("change", applyLayout);
    else if (mqAny.addListener) mqAny.addListener(applyLayout);

    const vv = window.visualViewport;
    function realKbPx(): number {
      if (!vv) return 0;
      return Math.max(0, window.innerHeight - vv.height);
    }
    // 정적 캡처에서는 realKbPx() 가 대부분 0 이라 화면에 보이는 열림·닫힘은
    // 아래 목표값 lerp 가 만든다 — 실제 기기에서는 이 값이 목표값을 대신한다.
    let current = 0;
    let target = 0;
    let lastFlip = 0;
    let playing = true;
    let raf = 0;

    function tick(now: number): void {
      if (now - lastFlip > 900) {
        target = target === 0 ? 1 : 0;
        lastFlip = now;
      }
      current += (target - current) * 0.12;
      sheet!.style.setProperty("--kb", current.toFixed(4));
      if (playing) raf = requestAnimationFrame(tick);
    }

    function stop(): void {
      playing = false;
      sheet!.style.setProperty("--kb", "0");
    }
    root.addEventListener("pointerdown", stop);

    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    if (reduce) {
      sheet.style.setProperty("--kb", String(realKbPx() > 0 ? 1 : 0.4));
    } else {
      raf = requestAnimationFrame((t) => {
        lastFlip = t;
        tick(t);
      });
    }

    return () => {
      playing = false;
      cancelAnimationFrame(raf);
      root.removeEventListener("pointerdown", stop);
      if (mq.removeEventListener) mq.removeEventListener("change", applyLayout);
      else if (mqAny.removeListener) mqAny.removeListener(applyLayout);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  return (
    <main className={styles.stage}>
      <div className={styles.ms} ref={rootRef}>
        <p className={styles.hint}>{HINT}</p>
        <div className={styles.field}>
          <input
            className={styles.input}
            type="text"
            defaultValue="파인애플"
            readOnly
            aria-label={ARIA_LABEL}
            style={{ caretColor: color, transitionDuration: duration, transitionTimingFunction: easing }}
          />
        </div>
        <div className={styles.sheet} ref={sheetRef}>
          <span className={styles.handle} aria-hidden="true" />
          <ul className={styles.list} ref={listRef} role="listbox" aria-label={LIST_LABEL} />
        </div>
      </div>
    </main>
  );
}