09Reduced-motion static save notice — with reduced motion, only the label's text value changes instead of animating

<main class="stage">
<div class="srm is-demo" id="srm">
  <div class="srm__panel">
    <span class="srm__tag">Normal motion</span>
    <span class="srm__badge" id="srmBadgeA"><span class="srm__dot"></span><span id="srmLabelA">Saving</span></span>
  </div>
  <div class="srm__panel">
    <span class="srm__tag">Reduced motion</span>
    <span class="srm__badge srm__badge--static" id="srmBadgeB"><span class="srm__dot"></span><span id="srmLabelB">Saving</span></span>
  </div>
</div>
</main>

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

// 계산 겹: 일반 판은 경과시간 기반 sin 진폭으로 밝기가 바뀌고, 모션 감소 판은 같은 상태 값을 트윈 없이 즉시 반영 — index.html 참조
@include stage($stage-paper);

.srm {
  display: flex;
  gap: $sp-5;
  cursor: pointer;
}

.srm__panel {
  display: grid;
  justify-items: center;
  gap: $sp-2;
  padding: $sp-4 $sp-5;
  border-radius: $r-card;
  background: $subject-cream;
}

.srm__tag {
  font: 600 10px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: rgba($stage-ink, .6);
  text-transform: uppercase;
  letter-spacing: .04em;
}

.srm__badge {
  display: flex;
  align-items: center;
  gap: $sp-2;
  padding: $sp-2 $sp-3;
  border-radius: $r-pill;
  background: $stage-ink;
  color: $subject-cream;
  font: 700 12px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.srm__dot {
  width: 7px;
  height: 7px;
  border-radius: $r-pill;
  background: $subject-blue-light;
  flex: 0 0 auto;
}

.srm__badge--done .srm__dot { background: $subject-mint; }

@media (max-width: 340px) {
  .srm { gap: $sp-3; }
  .srm__panel { padding: $sp-3 $sp-4; }
  .srm__badge { font-size: 11px; }
}

@media (prefers-reduced-motion: reduce) {
  // 모션 감소 판의 값 갱신은 원래 트윈이 없다 — OS 설정이 켜지면 일반 판도 밝기 계산을 건너뛴다(index.html)
  .srm__badge { 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);
}

.srm {
  display: flex;
  gap: 20px;
  cursor: pointer;
}

.srm__panel {
  display: grid;
  justify-items: center;
  gap: 8px;
  padding: 16px 20px;
  border-radius: 16px;
  background: #fff7e6;
}

.srm__tag {
  font: 600 10px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: rgba(23, 20, 26, 0.6);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.srm__badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  background: #17141a;
  color: #fff7e6;
  font: 700 12px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.srm__dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: #5b8cf8;
  flex: 0 0 auto;
}

.srm__badge--done .srm__dot {
  background: #4cd4a6;
}

@media (max-width: 340px) {
  .srm {
    gap: 12px;
  }
  .srm__panel {
    padding: 12px 16px;
  }
  .srm__badge {
    font-size: 11px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .srm__badge {
    transition: none;
  }
}

(function () {
  var root = document.getElementById('srm');
  var badgeA = document.getElementById('srmBadgeA');
  var labelA = document.getElementById('srmLabelA');
  var badgeB = document.getElementById('srmBadgeB');
  var labelB = document.getElementById('srmLabelB');

  // 상수: Saving 유지시간 · Saved 유지시간 · 일반 판 펄스 한 주기
  var SAVING_MS = 900;
  var IDLE_MS = 700;
  var PULSE_PERIOD_MS = 500;

  var phase = 'saving';
  var phaseStart = null;

  // 계산 겹: 일반 판은 경과시간 기반 sin 진폭으로 서서히 밝기가 바뀌고, Reduced motion 판은 같은 상태 값을 트윈 없이 즉시 반영한다
  function raf(ts) {
    if (phaseStart === null) phaseStart = ts;
    var el = ts - phaseStart;
    if (phase === 'saving') {
      var t = (el % PULSE_PERIOD_MS) / PULSE_PERIOD_MS;
      badgeA.style.opacity = (0.5 + 0.5 * (0.5 + 0.5 * Math.sin(t * Math.PI * 2))).toFixed(3);
      if (el > SAVING_MS) {
        phase = 'idle'; phaseStart = ts;
        labelA.textContent = labelB.textContent = 'Saved';
        badgeA.style.opacity = '1';
        badgeA.classList.add('srm__badge--done'); badgeB.classList.add('srm__badge--done');
      }
    } else {
      if (el > IDLE_MS) {
        phase = 'saving'; phaseStart = ts;
        labelA.textContent = labelB.textContent = 'Saving';
        badgeA.classList.remove('srm__badge--done'); badgeB.classList.remove('srm__badge--done');
      }
    }
    requestAnimationFrame(raf);
  }

  root.addEventListener('click', function () {
    root.classList.remove('is-demo');
    phase = 'saving';
    phaseStart = null;
    labelA.textContent = labelB.textContent = 'Saving';
    badgeA.classList.remove('srm__badge--done'); badgeB.classList.remove('srm__badge--done');
  });

  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  if (!reduce) { requestAnimationFrame(raf); }
  else {
    // Reduced motion 설정에서는 일반 판도 펄스 계산 없이 상태만 값으로 바뀐다
    setInterval(function () {
      phase = phase === 'saving' ? 'idle' : 'saving';
      var text = phase === 'saving' ? 'Saving' : 'Saved';
      labelA.textContent = labelB.textContent = text;
      badgeA.style.opacity = '1';
      badgeA.classList.toggle('srm__badge--done', phase === 'idle');
      badgeB.classList.toggle('srm__badge--done', phase === 'idle');
    }, SAVING_MS);
  }
})();

import { useEffect, useRef } from "react";
import styles from "./SaveStatusReducedMotion.module.scss";

type Box<T> = { current: T };

export default function SaveStatusReducedMotion() {
  const rootRef = useRef(null) as unknown as Box<HTMLDivElement | null>;

  useEffect(() => {
    const root = rootRef.current;
    if (!root) return;
    const badges = Array.from(root.querySelectorAll(`.${styles.badge}`)) as HTMLElement[];
    const labels = Array.from(root.querySelectorAll(`.${styles.label}`)) as HTMLElement[];
    const badgeA = badges[0];
    const badgeB = badges[1];
    const labelA = labels[0];
    const labelB = labels[1];
    if (!badgeA || !badgeB || !labelA || !labelB) return;

    // 상수: 저장 중 유지시간 · 저장됨 유지시간 · 일반 판 펄스 한 주기
    const SAVING_MS = 900;
    const IDLE_MS = 700;
    const PULSE_PERIOD_MS = 500;

    let phase: "saving" | "idle" = "saving";
    let phaseStart: number | null = null;
    let rafId = 0;
    let intervalId = 0;

    // 계산 겹: 일반 판은 경과시간 기반 sin 진폭으로 서서히 밝기가 바뀌고, 모션 감소 판은 같은 상태 값을 트윈 없이 즉시 반영한다
    function raf(ts: number) {
      if (phaseStart === null) phaseStart = ts;
      const el = ts - phaseStart;
      if (phase === "saving") {
        const t = (el % PULSE_PERIOD_MS) / PULSE_PERIOD_MS;
        badgeA.style.opacity = (0.5 + 0.5 * (0.5 + 0.5 * Math.sin(t * Math.PI * 2))).toFixed(3);
        if (el > SAVING_MS) {
          phase = "idle"; phaseStart = ts;
          labelA.textContent = labelB.textContent = "저장됨";
          badgeA.style.opacity = "1";
          badgeA.classList.add(styles["badge--done"]); badgeB.classList.add(styles["badge--done"]);
        }
      } else {
        if (el > IDLE_MS) {
          phase = "saving"; phaseStart = ts;
          labelA.textContent = labelB.textContent = "저장 중";
          badgeA.classList.remove(styles["badge--done"]); badgeB.classList.remove(styles["badge--done"]);
        }
      }
      rafId = requestAnimationFrame(raf);
    }

    function onClick() {
      root!.classList.remove(styles["is-demo"]);
      phase = "saving"; phaseStart = null;
      labelA.textContent = labelB.textContent = "저장 중";
      badgeA.classList.remove(styles["badge--done"]); badgeB.classList.remove(styles["badge--done"]);
    }
    root.addEventListener("click", onClick);

    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    if (!reduce) {
      rafId = requestAnimationFrame(raf);
    } else {
      intervalId = window.setInterval(() => {
        phase = phase === "saving" ? "idle" : "saving";
        const text = phase === "saving" ? "저장 중" : "저장됨";
        labelA.textContent = labelB.textContent = text;
        badgeA.style.opacity = "1";
        badgeA.classList.toggle(styles["badge--done"], phase === "idle");
        badgeB.classList.toggle(styles["badge--done"], phase === "idle");
      }, SAVING_MS);
    }

    return () => {
      cancelAnimationFrame(rafId);
      window.clearInterval(intervalId);
      root!.removeEventListener("click", onClick);
    };
  }, []);

  return (
    <div ref={rootRef} className={`${styles.stage} ${styles.srm} ${styles["is-demo"]}`}>
      <div className={styles.panel}>
        <span className={styles.tag}>일반 모션</span>
        <span className={styles.badge}>
          <span className={styles.dot} />
          <span className={styles.label}>저장 중</span>
        </span>
      </div>
      <div className={styles.panel}>
        <span className={styles.tag}>모션 감소</span>
        <span className={styles.badge}>
          <span className={styles.dot} />
          <span className={styles.label}>저장 중</span>
        </span>
      </div>
    </div>
  );
}