06Success morph — the ring redraws itself into a check

<main class="stage">
<div class="sm is-demo" id="smRoot" role="group" tabindex="0" aria-label="File upload complete indicator">
  <svg class="sm__svg" viewBox="0 0 120 120" width="72" height="72" aria-hidden="true">
    <circle class="sm__track" cx="60" cy="60" r="50"></circle>
    <circle class="sm__ring" id="smRing" cx="60" cy="60" r="50"></circle>
    <path class="sm__check" id="smCheck" d="M40 62 L54 76 L82 46"></path>
  </svg>
  <div class="sm__bar">
    <span class="sm__label">Upload complete</span>
    <span class="sm__meta">stroke-dasharray · path · transition</span>
  </div>
</div>
</main>

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

// 완료 모프(06) — 링과 체크는 서로 다른 <circle>/<path> 두 개다. 100% 지점에서 opacity 를
// steps(1,end) 로 순간 스왑하고, 체크는 그 즉시 stroke-dashoffset 을 0 까지 그려 넣는다(draw-in).

@property --p {
  syntax: "<number>";
  inherits: false;
  initial-value: 0;
}
@property --d {
  syntax: "<number>";
  inherits: false;
  initial-value: 0;
}

@include stage($stage-yellow);

$sm-text: $subject-ink;
$sm-ring: $subject-blue-deep;
$sm-check: $subject-blue-deep;

$duration: $dur-loop;
$easing: $ease-out;
$color: $sm-ring;

.sm {
  display: flex; flex-direction: column; align-items: center; gap: $sp-3;
  width: 100%; height: 100%; min-height: 164px;
  justify-content: center;
}
.sm:focus-visible { outline: 2px solid $sm-ring; outline-offset: 3px; border-radius: $r-control; }

.sm__svg { transform: rotate(-90deg); }
.sm__track { fill: none; stroke: rgba($sm-text, .16); stroke-width: 8; }
.sm__ring {
  fill: none;
  stroke: $sm-ring;
  stroke-width: 8;
  stroke-linecap: round;
  --circ: 0; --p: 0;
  stroke-dasharray: var(--circ);
  stroke-dashoffset: calc(var(--circ) * (1 - var(--p) / 100));
  transition: stroke-dashoffset $dur-quick linear;
}
.sm__check {
  fill: none;
  stroke: $sm-check;
  stroke-width: 8;
  stroke-linecap: round;
  stroke-linejoin: round;
  transform: rotate(90deg);
  transform-origin: 60px 60px;
  --checklen: 0; --d: 0;
  stroke-dasharray: var(--checklen);
  stroke-dashoffset: calc(var(--checklen) * (1 - var(--d) / 100));
  opacity: 0;
}
.sm__ring { opacity: 1; }
.sm.is-done .sm__ring { opacity: 0; transition: opacity $dur-instant linear; }
.sm.is-done .sm__check { opacity: 1; transition: stroke-dashoffset $dur-enter $ease-out, opacity $dur-instant linear; }
.sm.is-done .sm__check { --d: 100; }

.sm__bar { display: flex; flex-direction: column; align-items: center; gap: $sp-1; }
.sm__label { font-weight: 600; font-size: 11px; color: rgba($sm-text, .82); }
.sm__meta { font-weight: 500; font-size: 10px; color: rgba($sm-text, .62); }

// ── 데모 루프 — 66% 지점에서 링→체크 순간 스왑, 곧바로 체크가 그려진다 ──
@keyframes smRingArc {
  0%   { --p: 0; }
  66%  { --p: 100; animation-timing-function: steps(1, end); }
  67%  { opacity: 0; }
  88%  { opacity: 0; }
  92%  { opacity: 0; --p: 0; }
  94%  { opacity: 1; }
  100% { opacity: 1; --p: 0; }
}
@keyframes smCheckDraw {
  0%, 66% { opacity: 0; --d: 0; }
  67%     { opacity: 1; animation-timing-function: $ease-out; }
  80%     { --d: 100; }
  88%     { --d: 100; opacity: 1; }
  92%     { opacity: 0; --d: 0; }
  100%    { opacity: 0; --d: 0; }
}

.is-demo .sm__ring {
  animation-name: smRingArc;
  animation-duration: $duration;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
.is-demo .sm__check {
  animation-name: smCheckDraw;
  animation-duration: $duration;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

@media (max-width: 340px) {
  .sm__svg { width: 60px; height: 60px; }
}

@media (prefers-reduced-motion: reduce) {
  .is-demo .sm__ring, .is-demo .sm__check { animation: none !important; }
  .is-demo .sm__ring { opacity: 0 !important; }
  .is-demo .sm__check { opacity: 1 !important; --d: 100 !important; }
}

@property --p {
  syntax: "<number>";
  inherits: false;
  initial-value: 0;
}
@property --d {
  syntax: "<number>";
  inherits: false;
  initial-value: 0;
}
html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.sm {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  width: 100%;
  height: 100%;
  min-height: 164px;
  justify-content: center;
}

.sm:focus-visible {
  outline: 2px solid #0a4fe8;
  outline-offset: 3px;
  border-radius: 12px;
}

.sm__svg {
  transform: rotate(-90deg);
}

.sm__track {
  fill: none;
  stroke: rgba(23, 20, 26, 0.16);
  stroke-width: 8;
}

.sm__ring {
  fill: none;
  stroke: #0a4fe8;
  stroke-width: 8;
  stroke-linecap: round;
  --circ: 0;
  --p: 0;
  stroke-dasharray: var(--circ);
  stroke-dashoffset: calc(var(--circ) * (1 - var(--p) / 100));
  transition: stroke-dashoffset 220ms linear;
}

.sm__check {
  fill: none;
  stroke: #0a4fe8;
  stroke-width: 8;
  stroke-linecap: round;
  stroke-linejoin: round;
  transform: rotate(90deg);
  transform-origin: 60px 60px;
  --checklen: 0;
  --d: 0;
  stroke-dasharray: var(--checklen);
  stroke-dashoffset: calc(var(--checklen) * (1 - var(--d) / 100));
  opacity: 0;
}

.sm__ring {
  opacity: 1;
}

.sm.is-done .sm__ring {
  opacity: 0;
  transition: opacity 140ms linear;
}

.sm.is-done .sm__check {
  opacity: 1;
  transition: stroke-dashoffset 600ms ease-out, opacity 140ms linear;
}

.sm.is-done .sm__check {
  --d: 100;
}

.sm__bar {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.sm__label {
  font-weight: 600;
  font-size: 11px;
  color: rgba(23, 20, 26, 0.82);
}

.sm__meta {
  font-weight: 500;
  font-size: 10px;
  color: rgba(23, 20, 26, 0.62);
}

@keyframes smRingArc {
  0% {
    --p: 0;
  }
  66% {
    --p: 100;
    animation-timing-function: steps(1, end);
  }
  67% {
    opacity: 0;
  }
  88% {
    opacity: 0;
  }
  92% {
    opacity: 0;
    --p: 0;
  }
  94% {
    opacity: 1;
  }
  100% {
    opacity: 1;
    --p: 0;
  }
}
@keyframes smCheckDraw {
  0%, 66% {
    opacity: 0;
    --d: 0;
  }
  67% {
    opacity: 1;
    animation-timing-function: ease-out;
  }
  80% {
    --d: 100;
  }
  88% {
    --d: 100;
    opacity: 1;
  }
  92% {
    opacity: 0;
    --d: 0;
  }
  100% {
    opacity: 0;
    --d: 0;
  }
}
.is-demo .sm__ring {
  animation-name: smRingArc;
  animation-duration: 2s;
  animation-timing-function: ease-out;
  animation-iteration-count: infinite;
}

.is-demo .sm__check {
  animation-name: smCheckDraw;
  animation-duration: 2s;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

@media (max-width: 340px) {
  .sm__svg {
    width: 60px;
    height: 60px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .is-demo .sm__ring, .is-demo .sm__check {
    animation: none !important;
  }
  .is-demo .sm__ring {
    opacity: 0 !important;
  }
  .is-demo .sm__check {
    opacity: 1 !important;
    --d: 100 !important;
  }
}

// 완료 모프 — 100% 가 되는 프레임에 링을 즉시 숨기고 체크 path 를 즉시 보이게 스왑한 뒤
// 체크의 stroke-dashoffset 을 transition 으로 0 까지 되감아(draw-in) 원이 체크로 이어져
// 그려진 것처럼 보이게 만든다. d 속성 자체는 절대 보간되지 않으므로 스왑은 항상 순간적이다.
(function () {
  var SEED = 0x9917cf;
  function mulberry32(a) {
    return function () {
      a |= 0; a = (a + 0x6D2B79F5) | 0;
      var t = Math.imul(a ^ (a >>> 15), 1 | a);
      t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
      return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
    };
  }
  var rand = mulberry32(SEED);

  var root  = document.getElementById('smRoot');
  var ring  = document.getElementById('smRing');
  var check = document.getElementById('smCheck');
  if (!root || !ring || !check) return;

  var ringBox = ring.getBoundingClientRect();
  var ringR = ringBox.width > 0 ? ringBox.width / 2 : ring.r.baseVal.value;
  var circ = 2 * Math.PI * ringR;
  ring.style.setProperty('--circ', String(circ));
  var checkLen = check.getTotalLength();
  check.style.setProperty('--checklen', String(checkLen));

  var target = 0, shown = 0, raf = null, timer = null;
  function paint() {
    shown += (target - shown) * 0.2;
    if (Math.abs(target - shown) < 0.1) shown = target;
    ring.style.setProperty('--p', shown.toFixed(2));
    if (shown >= 100) {
      root.classList.add('is-done');
      raf = null;
      return;
    }
    raf = requestAnimationFrame(paint);
  }
  function tick() {
    if (root.classList.contains('is-demo')) return;
    target = Math.min(100, target + 6 + rand() * 10);
    if (target >= 100) clearInterval(timer);
  }
  function live() {
    if (!root.classList.contains('is-demo')) return;
    root.classList.remove('is-demo');
    timer = setInterval(tick, 220);
    raf = requestAnimationFrame(paint);
  }
  ['pointerdown', 'focusin'].forEach(function (ev) { root.addEventListener(ev, live); });
})();

// UploadProgressSuccessMorph — vanilla 판(run/329/demo/06-upload-progress-success-morph/index.html) 의 React 포트.
// 100% 가 되는 프레임에 링을 즉시 숨기고 체크 path 를 즉시 보이게 스왑한 뒤 체크의 stroke-dashoffset 을
// transition 으로 0 까지 되감아(draw-in) 원이 체크로 이어져 그려진 것처럼 보이게 만든다.
// d 속성 자체는 절대 보간되지 않으므로 스왑은 항상 순간적이다.
import { useEffect, useRef, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./UploadProgressSuccessMorph.module.scss";

export type UploadProgressSuccessMorphProps = {
  duration?: string;
  easing?: string;
  color?: string;
  seed?: number;      // mulberry32 시드
  stepBase?: number;  // 매 틱 기본 증가분(퍼센트 포인트)
  stepJitter?: number; // 매 틱 랜덤 증가분 상한
  tickMs?: number;    // 진행 틱 주기(ms)
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
type Box<T> = { current: T };

const LABEL = "업로드 완료";
const META = "stroke-dasharray · path · transition";
const SEED = 0x9917cf;

function mulberry32(a: number): () => number {
  return function () {
    a |= 0; a = (a + 0x6D2B79F5) | 0;
    const t = Math.imul(a ^ (a >>> 15), 1 | a);
    const u = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
    return ((u ^ (u >>> 14)) >>> 0) / 4294967296;
  };
}

export default function UploadProgressSuccessMorph({
  duration = "2s",
  easing = "ease-out",
  color = "#0a4fe8",
  seed = SEED,
  stepBase = 6,
  stepJitter = 10,
  tickMs = 220
}: UploadProgressSuccessMorphProps) {
  const [demo, setDemo] = useState(true);
  const [done, setDone] = useState(false);
  const ringRef = useRef<SVGCircleElement | null>(null);
  const checkRef = useRef<SVGPathElement | null>(null);
  const targetRef = useRef(0) as Box<number>;
  const shownRef = useRef(0) as Box<number>;
  const rafRef = useRef(0) as Box<number>;
  const timerRef = useRef(0) as Box<number>;
  const vars: Vars = { "--duration": duration, "--easing": easing, "--color": color };

  useEffect(() => {
    return () => {
      window.clearInterval(timerRef.current);
      cancelAnimationFrame(rafRef.current);
    };
  }, []);

  function live(): void {
    if (!demo) return;
    setDemo(false);
    const ring = ringRef.current;
    const check = checkRef.current;
    if (!ring || !check) return;
    const rand = mulberry32(seed);

    const ringBox = ring.getBoundingClientRect();
    const ringR = ringBox.width > 0 ? ringBox.width / 2 : ring.r.baseVal.value;
    const circ = 2 * Math.PI * ringR;
    ring.style.setProperty("--circ", String(circ));
    const checkLen = check.getTotalLength();
    check.style.setProperty("--checklen", String(checkLen));

    function paint(): void {
      shownRef.current += (targetRef.current - shownRef.current) * 0.2;
      if (Math.abs(targetRef.current - shownRef.current) < 0.1) shownRef.current = targetRef.current;
      ring!.style.setProperty("--p", shownRef.current.toFixed(2));
      if (shownRef.current >= 100) {
        setDone(true);
        return;
      }
      rafRef.current = requestAnimationFrame(paint);
    }
    function tick(): void {
      targetRef.current = Math.min(100, targetRef.current + stepBase + rand() * stepJitter);
      if (targetRef.current >= 100) window.clearInterval(timerRef.current);
    }
    timerRef.current = window.setInterval(tick, tickMs);
    rafRef.current = requestAnimationFrame(paint);
  }

  const rootCls = [styles.sm, demo ? styles.isDemo : "", done ? styles.isDone : ""].filter(Boolean).join(" ");

  return (
    <main className={styles.stage}>
      <div
        className={rootCls}
        style={vars}
        role="group"
        tabIndex={0}
        aria-label="파일 업로드 완료 표시"
        onPointerDown={live}
        onFocus={live}
      >
        <svg className={styles.svg} viewBox="0 0 120 120" width="72" height="72" aria-hidden="true">
          <circle className={styles.track} cx="60" cy="60" r="50"></circle>
          <circle className={styles.ring} cx="60" cy="60" r="50" ref={ringRef}></circle>
          <path className={styles.check} d="M40 62 L54 76 L82 46" ref={checkRef}></path>
        </svg>
        <div className={styles.bar}>
          <span className={styles.label}>{LABEL}</span>
          <span className={styles.meta}>{META}</span>
        </div>
      </div>
    </main>
  );
}