01ハンドル不要でオブジェクトごとドラッグ移動

<main class="stage">
<div class="scene is-demo" id="scene">
  <div class="grid" aria-hidden="true"></div>
  <div class="draggable" id="draggable" tabindex="0" aria-label="ドラッグして移動">
    <div class="selectBox">
      <div class="subjectShape"></div>
    </div>
  </div>
  <div class="readout" id="readout" aria-hidden="true">X <span id="rx">0</span> · Y <span id="ry">0</span></div>
</div>
</main>

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

// 변수 3개
$duration: $dur-enter;
$easing: $ease-out;
$color: $subject-lilac;

// 계산 겹: index.html 의 applyTransform() 이 포인터 델타를 matrix(1,0,0,1,tx,ty) 순수 이동 행렬로
// 그대로 굳혀 style.transform 에 넣는다 — CSS 트랜지션이 아니라 매 프레임 산술로 값을 만든다.
@include stage($stage-ink);

.scene {
  position: relative;
  width: 320px;
  height: 180px;
  border-radius: $r-card;
  overflow: hidden;
  box-shadow: $shadow-raised;
  background: linear-gradient(160deg, #201c2c, $stage-ink 70%);
}

.grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .05) 1px, transparent 1px);
  background-size: 20px 20px;
}

.draggable {
  position: absolute;
  top: 50%;
  left: 50%;
  margin-top: -34px;
  margin-left: -48px;
  width: 96px;
  height: 68px;
  cursor: grab;
  touch-action: none;
  will-change: transform;

  &.isDragging { cursor: grabbing; }
  &:focus-visible .selectBox { outline: 2px solid $color; outline-offset: 3px; }
}

.selectBox {
  position: relative;
  width: 100%;
  height: 100%;
  border: 1px dashed rgba($subject-cream, .4);
  border-radius: $r-sm;
  box-sizing: border-box;
  display: grid;
  place-items: center;
}

.subjectShape {
  width: 72px;
  height: 48px;
  border-radius: $r-sm;
  background: linear-gradient(135deg, $subject-pink, $subject-lilac);
  box-shadow: $shadow-press;
}

.readout {
  position: absolute;
  left: $sp-3;
  bottom: $sp-3;
  padding: $sp-1 $sp-2;
  border-radius: $r-pill;
  background: rgba(#050409, .5);
  color: rgba($subject-cream, .82);
  font-size: 10px;
  font-variant-numeric: tabular-nums;
  letter-spacing: .02em;
}

@media (max-width: 340px) {
  .scene { width: 220px; height: 124px; }
  .draggable { width: 68px; height: 48px; margin-top: -24px; margin-left: -34px; }
  .subjectShape { width: 52px; height: 34px; }
  .readout { font-size: 9px; }
}

@media (prefers-reduced-motion: reduce) {
  // 실사용 경로 적용 — 드래그·키보드 이동은 index.html 이 트윈 없이 즉시 반영한다.
  // scss 만: 포커스 아웃라인 전환만 꺼서 잔여 트랜지션을 없앤다.
  .draggable { transition: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.scene {
  position: relative;
  width: 320px;
  height: 180px;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  background: linear-gradient(160deg, #201c2c, #17141a 70%);
}

.grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px), linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 20px 20px;
}

.draggable {
  position: absolute;
  top: 50%;
  left: 50%;
  margin-top: -34px;
  margin-left: -48px;
  width: 96px;
  height: 68px;
  cursor: grab;
  touch-action: none;
  will-change: transform;
}
.draggable.isDragging {
  cursor: grabbing;
}
.draggable:focus-visible .selectBox {
  outline: 2px solid #b9a0ff;
  outline-offset: 3px;
}

.selectBox {
  position: relative;
  width: 100%;
  height: 100%;
  border: 1px dashed rgba(255, 247, 230, 0.4);
  border-radius: 8px;
  box-sizing: border-box;
  display: grid;
  place-items: center;
}

.subjectShape {
  width: 72px;
  height: 48px;
  border-radius: 8px;
  background: linear-gradient(135deg, #ff9ebb, #b9a0ff);
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
}

.readout {
  position: absolute;
  left: 12px;
  bottom: 12px;
  padding: 4px 8px;
  border-radius: 999px;
  background: rgba(5, 4, 9, 0.5);
  color: rgba(255, 247, 230, 0.82);
  font-size: 10px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

@media (max-width: 340px) {
  .scene {
    width: 220px;
    height: 124px;
  }
  .draggable {
    width: 68px;
    height: 48px;
    margin-top: -24px;
    margin-left: -34px;
  }
  .subjectShape {
    width: 52px;
    height: 34px;
  }
  .readout {
    font-size: 9px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .draggable {
    transition: none;
  }
}

(function () {
  var WAYPOINTS = [
    { x: 0, y: 0 },
    { x: 92, y: -38 },
    { x: -70, y: 30 },
    { x: 0, y: 0 }
  ];
  var HOP_MS = 640;
  var HOLD_MS = 380;

  var scene = document.getElementById('scene');
  var el = document.getElementById('draggable');
  var rx = document.getElementById('rx');
  var ry = document.getElementById('ry');
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  var tx = 0, ty = 0;
  var dragging = false;
  var startX = 0, startY = 0, originTx = 0, originTy = 0;
  var timers = [];

  function clamp(v, lo, hi) { return Math.min(hi, Math.max(lo, v)); }
  function easeOutCubic(t) { return 1 - Math.pow(1 - t, 3); }

  // 포인터 델타 → translate 행렬. matrix(1,0,0,1,tx,ty) 가 곧 순수 이동 행렬이다.
  function applyTransform(nx, ny) {
    tx = nx; ty = ny;
    el.style.transform = 'matrix(1,0,0,1,' + tx.toFixed(1) + ',' + ty.toFixed(1) + ')';
    rx.textContent = Math.round(tx);
    ry.textContent = Math.round(ty);
  }

  function human() {
    if (scene.classList.contains('is-demo')) {
      scene.classList.remove('is-demo');
      timers.forEach(function (t) { clearTimeout(t); clearInterval(t); });
      timers = [];
    }
  }

  function onPointerDown(e) {
    human();
    dragging = true;
    el.setPointerCapture(e.pointerId);
    startX = e.clientX; startY = e.clientY;
    originTx = tx; originTy = ty;
    el.classList.add('isDragging');
  }
  function onPointerMove(e) {
    if (!dragging) return;
    var dx = e.clientX - startX;
    var dy = e.clientY - startY;
    applyTransform(clamp(originTx + dx, -110, 110), clamp(originTy + dy, -55, 55));
  }
  function onPointerUp(e) {
    if (!dragging) return;
    dragging = false;
    el.classList.remove('isDragging');
    try { el.releasePointerCapture(e.pointerId); } catch (err) {}
  }
  function onKeydown(e) {
    var step = e.shiftKey ? 10 : 1;
    if (e.key === 'ArrowLeft') { human(); applyTransform(clamp(tx - step, -110, 110), ty); e.preventDefault(); }
    else if (e.key === 'ArrowRight') { human(); applyTransform(clamp(tx + step, -110, 110), ty); e.preventDefault(); }
    else if (e.key === 'ArrowUp') { human(); applyTransform(tx, clamp(ty - step, -55, 55)); e.preventDefault(); }
    else if (e.key === 'ArrowDown') { human(); applyTransform(tx, clamp(ty + step, -55, 55)); e.preventDefault(); }
  }

  el.addEventListener('pointerdown', onPointerDown);
  el.addEventListener('pointermove', onPointerMove);
  el.addEventListener('pointerup', onPointerUp);
  el.addEventListener('pointercancel', onPointerUp);
  el.addEventListener('keydown', onKeydown);

  // reduce: 실사용 경로 적용 — 포인터·키보드 이동은 위 리스너가 그대로 처리한다(트윈 없이 즉시 반영).
  // 아래 hopTo()·cycle() 은 시연 게이트만 — reduce 에서는 돌지 않는다.
  function hopTo(target, onDone) {
    var fromTx = tx, fromTy = ty;
    var start = performance.now();
    function frame(now) {
      if (!scene.classList.contains('is-demo')) return;
      var p = clamp((now - start) / HOP_MS, 0, 1);
      var e = easeOutCubic(p);
      applyTransform(fromTx + (target.x - fromTx) * e, fromTy + (target.y - fromTy) * e);
      if (p < 1) requestAnimationFrame(frame);
      else if (onDone) onDone();
    }
    requestAnimationFrame(frame);
  }

  function cycle(i) {
    if (!scene.classList.contains('is-demo')) return;
    var next = WAYPOINTS[i % WAYPOINTS.length];
    hopTo(next, function () {
      timers.push(setTimeout(function () { cycle(i + 1); }, HOLD_MS));
    });
  }

  if (!reduce) {
    cycle(1);
  }
})();

import { useEffect, useRef } from 'react';
import styles from './XfDragMove.module.scss';

const STEP_PX = 1; // 방향키 한 번의 기본 이동량
const STEP_PX_SHIFT = 10; // Shift + 방향키
const HOP_MS = 620;
const HOLD_MS = 360;
const WAYPOINTS = [
  { x: 0, y: 0 }, { x: 92, y: -38 }, { x: -70, y: 30 }, { x: 0, y: 0 }
];

export default function XfDragMove() {
  const sceneRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    const scene0 = sceneRef.current;
    if (!scene0) return undefined;
    const scene = scene0;
    const draggable0 = scene.querySelector<HTMLDivElement>('.' + styles.draggable);
    const rx0 = scene.querySelector<HTMLSpanElement>('#rx');
    const ry0 = scene.querySelector<HTMLSpanElement>('#ry');
    if (!draggable0 || !rx0 || !ry0) return undefined;
    const draggable = draggable0;
    const rx = rx0;
    const ry = ry0;

    const reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

    let tx = 0, ty = 0;
    let dragging = false;
    let startX = 0, startY = 0, originTx = 0, originTy = 0;
    let rafId = 0;
    let timers: number[] = [];

    function clamp(v: number, lo: number, hi: number) { return Math.min(hi, Math.max(lo, v)); }
    function easeOutCubic(t: number) { return 1 - Math.pow(1 - t, 3); }

    // 포인터 델타 → translate 행렬. matrix(1,0,0,1,tx,ty) 가 곧 순수 이동 행렬이다.
    function applyTransform(nx: number, ny: number) {
      tx = nx; ty = ny;
      draggable.style.transform = 'matrix(1,0,0,1,' + tx.toFixed(1) + ',' + ty.toFixed(1) + ')';
      rx.textContent = String(Math.round(tx));
      ry.textContent = String(Math.round(ty));
    }

    function human() {
      if (scene.classList.contains(styles['is-demo'])) {
        scene.classList.remove(styles['is-demo']);
        timers.forEach((t) => window.clearTimeout(t));
        timers = [];
      }
    }

    function onPointerDown(e: PointerEvent) {
      human();
      dragging = true;
      draggable.setPointerCapture(e.pointerId);
      startX = e.clientX; startY = e.clientY;
      originTx = tx; originTy = ty;
    }
    function onPointerMove(e: PointerEvent) {
      if (!dragging) return;
      applyTransform(originTx + (e.clientX - startX), originTy + (e.clientY - startY));
    }
    function endDrag(e: PointerEvent) {
      if (!dragging) return;
      dragging = false;
      try { draggable.releasePointerCapture(e.pointerId); } catch { /* 캡처가 이미 풀린 경우 */ }
    }
    function onKeyDown(e: KeyboardEvent) {
      const step = e.shiftKey ? STEP_PX_SHIFT : STEP_PX;
      if (e.key === 'ArrowLeft') { human(); applyTransform(tx - step, ty); e.preventDefault(); }
      else if (e.key === 'ArrowRight') { human(); applyTransform(tx + step, ty); e.preventDefault(); }
      else if (e.key === 'ArrowUp') { human(); applyTransform(tx, ty - step); e.preventDefault(); }
      else if (e.key === 'ArrowDown') { human(); applyTransform(tx, ty + step); e.preventDefault(); }
    }

    draggable.addEventListener('pointerdown', onPointerDown);
    draggable.addEventListener('pointermove', onPointerMove);
    draggable.addEventListener('pointerup', endDrag);
    draggable.addEventListener('pointercancel', endDrag);
    draggable.addEventListener('keydown', onKeyDown);

    // reduce: 실사용 경로 적용 — 드래그·키보드는 위에서 즉시 반영한다.
    // 아래 자동 루프는 시연 게이트만 — reduce 에서는 돌지 않는다.
    function hopTo(target: { x: number; y: number }, onDone: () => void) {
      const fromX = tx, fromY = ty;
      const start = performance.now();
      function frame(now: number) {
        if (!scene.classList.contains(styles['is-demo'])) return;
        const p = clamp((now - start) / HOP_MS, 0, 1);
        const e = easeOutCubic(p);
        applyTransform(fromX + (target.x - fromX) * e, fromY + (target.y - fromY) * e);
        if (p < 1) rafId = requestAnimationFrame(frame);
        else onDone();
      }
      rafId = requestAnimationFrame(frame);
    }

    function cycle(i: number) {
      if (!scene.classList.contains(styles['is-demo'])) return;
      const target = WAYPOINTS[i % WAYPOINTS.length];
      hopTo(target, () => {
        timers.push(window.setTimeout(() => cycle(i + 1), HOLD_MS));
      });
    }

    applyTransform(0, 0);
    if (!reduce) {
      cycle(1);
    }

    return () => {
      draggable.removeEventListener('pointerdown', onPointerDown);
      draggable.removeEventListener('pointermove', onPointerMove);
      draggable.removeEventListener('pointerup', endDrag);
      draggable.removeEventListener('pointercancel', endDrag);
      draggable.removeEventListener('keydown', onKeyDown);
      timers.forEach((t) => window.clearTimeout(t));
      cancelAnimationFrame(rafId);
    };
  }, []);

  return (
    <main className={styles.stage}>
      <div className={styles.scene + ' ' + styles['is-demo']} ref={sceneRef}>
        <div
          className={styles.draggable}
          tabIndex={0}
          aria-label="드래그해서 이동"
        >
          <span className={styles.selectBox} aria-hidden="true"></span>
          <span className={styles.subjectShape} aria-hidden="true"></span>
        </div>
        <div className={styles.readout} aria-hidden="true">X <span id="rx">0</span> · Y <span id="ry">0</span></div>
      </div>
    </main>
  );
}