05セルを引いて四角に囲み、まとめてコピー

<main class="stage">
  <div class="rs is-demo" id="rs">
    <div class="rs__grid" id="rs-grid" role="grid" aria-label="週間売上">
      <div class="rs__row rs__row--head" role="row">
        <span role="columnheader">月</span><span role="columnheader">火</span><span role="columnheader">水</span><span role="columnheader">木</span>
      </div>
      <div class="rs__row" role="row"><b data-r="0" data-c="0" role="gridcell">12</b><b data-r="0" data-c="1" role="gridcell">18</b><b data-r="0" data-c="2" role="gridcell">9</b><b data-r="0" data-c="3" role="gridcell">24</b></div>
      <div class="rs__row" role="row"><b data-r="1" data-c="0" role="gridcell">7</b><b data-r="1" data-c="1" role="gridcell">15</b><b data-r="1" data-c="2" role="gridcell">21</b><b data-r="1" data-c="3" role="gridcell">6</b></div>
      <div class="rs__row" role="row"><b data-r="2" data-c="0" role="gridcell">30</b><b data-r="2" data-c="1" role="gridcell">11</b><b data-r="2" data-c="2" role="gridcell">3</b><b data-r="2" data-c="3" role="gridcell">17</b></div>
      <div class="rs__box" id="rs-box" aria-hidden="true"></div>
    </div>
    <p class="rs__foot" id="rs-foot" role="status">
      <span class="rs__s0">ドラッグして選択</span>
      <span class="rs__s1">1マス · 合計 12</span>
      <span class="rs__s2">4マス · 合計 52</span>
      <span class="rs__s3">9マス · 合計 126</span>
    </p>
    <span class="rs__toast" aria-hidden="true"><span class="rs__toast-in"><span class="rs__ic"><svg viewBox="0 0 256 256" width="1em" height="1em" fill="currentColor"><g><path d="M216 40v128h-48V88H88V40Z" opacity=".2"/><path d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z"/></g></svg></span>コピーしました</span></span>
  </div>
</main>

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

$duration: $dur-quick;
$easing: $ease-spring;
$color: $subject-sky;

@include stage($stage-ink);

$cell-w: 66px;
$cell-h: 26px;
$line: color.mix($subject-cream, $stage-ink, 14%);

.rs {
  position: relative;
  box-sizing: border-box;
  width: 264px;
  color: $subject-cream;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.rs__grid {
  position: relative;
  border: 1px solid $line;
  border-radius: $r-control;
  background: $stage-ink;
  overflow: hidden;
}
.rs__row {
  display: grid;
  grid-template-columns: repeat(4, $cell-w);
  height: $cell-h;
}
.rs__row + .rs__row { border-top: 1px solid rgba(255, 247, 230, .07); }
.rs__row > * {
  padding: 0 $sp-2;
  font-size: 12px;
  line-height: $cell-h;
  font-weight: 600;
  text-align: right;
  overflow: hidden;
  white-space: nowrap;
  transition: background $duration $easing;
}
.rs__row--head {
  background: color.mix($subject-cream, $stage-ink, 8%);
}
.rs__row--head > * {
  color: rgba(255, 247, 230, .56);
  font-size: 11px;
  font-weight: 700;
  text-align: center;
}
.rs__row > .is-sel { background: rgba(110, 200, 255, .22); }

// ── 범위 네모 — 셀 하나 크기를 기준으로 늘린다 ────────
.rs__box {
  position: absolute;
  left: 0; top: 0;
  width: $cell-w;
  height: $cell-h;
  border: 2px solid $color;
  border-radius: $r-xs;
  opacity: 0;
  transform-origin: left top; // 규칙8: 앵커셀 좌표 계산 기준
  transform: translate(0, $cell-h) scale(1, 1);
  pointer-events: none;
}

// ── 아래 띠 ──────────────────────────────────────────
.rs__foot {
  position: relative;
  height: 20px;
  margin: $sp-2 0 0;
  font-size: 11px;
  line-height: 20px;
  font-weight: 600;
}
.rs__s0, .rs__s1, .rs__s2, .rs__s3 {
  position: absolute;
  left: 0; top: 0;
  color: rgba(255, 247, 230, .62);
}
.rs__s1, .rs__s2, .rs__s3 { opacity: 0; color: $color; }

// ── 복사 쪽지 ────────────────────────────────────────
.rs__toast {
  position: absolute;
  right: 0; bottom: 24px;
  opacity: 0;
}
.rs.is-copied .rs__toast { opacity: 1; }
.rs__toast-in {
  display: inline-flex;
  align-items: center;
  gap: $sp-1;
  padding: 0 $sp-2;
  border-radius: $r-pill;
  background: $subject-mint;
  color: $subject-ink;
  font-size: 11px;
  line-height: 20px;
  font-weight: 700;
  transform: translateY(0);
}
.rs__ic { display: inline-flex; width: 12px; height: 12px; }

// ── 자동 루프 (2s) ───────────────────────────────────
// 10% 에 한 칸에서 시작해 44% 까지 세 칸 × 세 줄로 자란다(scale 하나로 — 네 변을 따로 재면 어긋난다).
// 칸 색과 아래 띠 문구는 네모가 그 칸에 닿는 순간마다 컷으로 바뀐다. 62% 에 쪽지가 튀어오르고
// 78~88% 에 한 칸으로 되돌아온다 — 복귀가 90% 안이라 24장 표본에 다 잡힌다.
.rs.is-demo .rs__box {
  animation-name: rs-box;
  animation-duration: $dur-loop;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__row > b {
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
// 네모가 1×1 → 2×2 → 3×3 으로 자라며 덮는 칸만 그 순간에 켠다
.rs.is-demo .rs__row:nth-child(2) > b:nth-child(1) { animation-name: rs-lit-a; }
.rs.is-demo .rs__row:nth-child(2) > b:nth-child(2),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(1),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(2) { animation-name: rs-lit-b; }
.rs.is-demo .rs__row:nth-child(2) > b:nth-child(3),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(3),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(1),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(2),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(3) { animation-name: rs-lit-c; }
.rs.is-demo .rs__s0 {
  animation-name: rs-hide;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__s1 {
  animation-name: rs-s1;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__s2 {
  animation-name: rs-s2;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__s3 {
  animation-name: rs-s3;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__toast {
  animation-name: rs-toast;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.rs.is-demo .rs__toast-in {
  animation-name: rs-pop;
  animation-duration: $dur-loop;
  animation-timing-function: $ease-pop;
  animation-iteration-count: infinite;
  animation-fill-mode: backwards;
}

// 줄어드는 구간에도 네모 크기와 아래 띠 문구가 **같은 순간에** 한 단계씩 내려간다.
// 네모만 줄이고 문구를 늦게 끄면 「2×2 네모 옆에 9칸·합계 126」 같은 거짓 장이 poster 로 뽑힌다 (실측)
@keyframes rs-box {
  0%   { opacity: 0; transform: translate(0, $cell-h) scale(1, 1); }
  10%  { opacity: 1; transform: translate(0, $cell-h) scale(1, 1); }
  44%  { opacity: 1; transform: translate(0, $cell-h) scale(3, 3); }
  76%  { opacity: 1; transform: translate(0, $cell-h) scale(3, 3); }
  80%  { opacity: 1; transform: translate(0, $cell-h) scale(2, 2); }
  84%  { opacity: 1; transform: translate(0, $cell-h) scale(1, 1); }
  86%  { opacity: 0; transform: translate(0, $cell-h) scale(1, 1); }
  100% { opacity: 0; transform: translate(0, $cell-h) scale(1, 1); }
}
// 켜는 것과 끄는 것이 같은 크기면 아홉 칸이 한꺼번에 꺼지는 장이 제일 크게 변해 poster 가 된다.
// 그래서 끄는 쪽은 켠 순서의 역순으로 흩어 둔다 — 한 장에서 꺼지는 칸 수를 다섯 → 넷 → 하나로.
@keyframes rs-lit-a {
  0%   { background: none; }
  10%  { background: rgba(110, 200, 255, .22); }
  86%  { background: none; }
  100% { background: none; }
}
@keyframes rs-s1 {
  0%   { opacity: 0; }
  10%  { opacity: 1; }
  26%  { opacity: 0; }
  82%  { opacity: 1; }
  86%  { opacity: 0; }
  100% { opacity: 0; }
}
@keyframes rs-lit-b {
  0%   { background: none; }
  26%  { background: rgba(110, 200, 255, .22); }
  81%  { background: none; }
  100% { background: none; }
}
@keyframes rs-lit-c {
  0%   { background: none; }
  40%  { background: rgba(110, 200, 255, .22); }
  78%  { background: none; }
  100% { background: none; }
}
@keyframes rs-hide {
  0%   { opacity: 1; }
  10%  { opacity: 0; }
  88%  { opacity: 1; }
  100% { opacity: 1; }
}
@keyframes rs-s2 {
  0%   { opacity: 0; }
  26%  { opacity: 1; }
  40%  { opacity: 0; }
  78%  { opacity: 1; }
  82%  { opacity: 0; }
  100% { opacity: 0; }
}
@keyframes rs-s3 {
  0%   { opacity: 0; }
  40%  { opacity: 1; }
  78%  { opacity: 0; }
  100% { opacity: 0; }
}
@keyframes rs-toast {
  0%   { opacity: 0; }
  62%  { opacity: 1; }
  80%  { opacity: 0; }
  100% { opacity: 0; }
}
@keyframes rs-pop {
  0%   { transform: translateY(10px); }
  62%  { transform: translateY(10px); }
  70%  { transform: translateY(0); }
  80%  { transform: translateY(0); }
  100% { transform: translateY(0); }
}

// 320×200 — 264px 격자가 그대로 들어가므로 아래 띠 여백만 줄인다
@media (max-width: 340px) {
  .rs__foot { margin-top: $sp-1; }
}

@media (prefers-reduced-motion: reduce) {
  .rs.is-demo .rs__box,
  .rs.is-demo .rs__row > b,
  .rs.is-demo .rs__s0,
  .rs.is-demo .rs__s1,
  .rs.is-demo .rs__s2,
  .rs.is-demo .rs__s3,
  .rs.is-demo .rs__toast,
  .rs.is-demo .rs__toast-in { animation: none !important; }
  .rs.is-demo .rs__box { opacity: 1; transform: translate(0, $cell-h) scale(3, 3); }
  .rs.is-demo .rs__s0 { opacity: 0; }
  .rs.is-demo .rs__s3 { opacity: 1; }
  .rs__row > * { 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);
}

.rs {
  position: relative;
  box-sizing: border-box;
  width: 264px;
  color: #fff7e6;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.rs__grid {
  position: relative;
  border: 1px solid rgb(21.7568627451%, 20.3058823529%, 21.3960784314%);
  border-radius: 12px;
  background: #17141a;
  overflow: hidden;
}

.rs__row {
  display: grid;
  grid-template-columns: repeat(4, 66px);
  height: 26px;
}

.rs__row + .rs__row {
  border-top: 1px solid rgba(255, 247, 230, 0.07);
}

.rs__row > * {
  padding: 0 8px;
  font-size: 12px;
  line-height: 26px;
  font-weight: 600;
  text-align: right;
  overflow: hidden;
  white-space: nowrap;
  transition: background 220ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.rs__row--head {
  background: rgb(16.2980392157%, 14.9647058824%, 16.5960784314%);
}

.rs__row--head > * {
  color: rgba(255, 247, 230, 0.56);
  font-size: 11px;
  font-weight: 700;
  text-align: center;
}

.rs__row > .is-sel {
  background: rgba(110, 200, 255, 0.22);
}

.rs__box {
  position: absolute;
  left: 0;
  top: 0;
  width: 66px;
  height: 26px;
  border: 2px solid #6ec8ff;
  border-radius: 4px;
  opacity: 0;
  transform-origin: left top;
  transform: translate(0, 26px) scale(1, 1);
  pointer-events: none;
}

.rs__foot {
  position: relative;
  height: 20px;
  margin: 8px 0 0;
  font-size: 11px;
  line-height: 20px;
  font-weight: 600;
}

.rs__s0, .rs__s1, .rs__s2, .rs__s3 {
  position: absolute;
  left: 0;
  top: 0;
  color: rgba(255, 247, 230, 0.62);
}

.rs__s1, .rs__s2, .rs__s3 {
  opacity: 0;
  color: #6ec8ff;
}

.rs__toast {
  position: absolute;
  right: 0;
  bottom: 24px;
  opacity: 0;
}

.rs.is-copied .rs__toast {
  opacity: 1;
}

.rs__toast-in {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0 8px;
  border-radius: 999px;
  background: #4cd4a6;
  color: #17141a;
  font-size: 11px;
  line-height: 20px;
  font-weight: 700;
  transform: translateY(0);
}

.rs__ic {
  display: inline-flex;
  width: 12px;
  height: 12px;
}

.rs.is-demo .rs__box {
  animation-name: rs-box;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__row > b {
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__row:nth-child(2) > b:nth-child(1) {
  animation-name: rs-lit-a;
}

.rs.is-demo .rs__row:nth-child(2) > b:nth-child(2),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(1),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(2) {
  animation-name: rs-lit-b;
}

.rs.is-demo .rs__row:nth-child(2) > b:nth-child(3),
.rs.is-demo .rs__row:nth-child(3) > b:nth-child(3),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(1),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(2),
.rs.is-demo .rs__row:nth-child(4) > b:nth-child(3) {
  animation-name: rs-lit-c;
}

.rs.is-demo .rs__s0 {
  animation-name: rs-hide;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__s1 {
  animation-name: rs-s1;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__s2 {
  animation-name: rs-s2;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__s3 {
  animation-name: rs-s3;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__toast {
  animation-name: rs-toast;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.rs.is-demo .rs__toast-in {
  animation-name: rs-pop;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 1.4, 0.4, 1);
  animation-iteration-count: infinite;
  animation-fill-mode: backwards;
}

@keyframes rs-box {
  0% {
    opacity: 0;
    transform: translate(0, 26px) scale(1, 1);
  }
  10% {
    opacity: 1;
    transform: translate(0, 26px) scale(1, 1);
  }
  44% {
    opacity: 1;
    transform: translate(0, 26px) scale(3, 3);
  }
  76% {
    opacity: 1;
    transform: translate(0, 26px) scale(3, 3);
  }
  80% {
    opacity: 1;
    transform: translate(0, 26px) scale(2, 2);
  }
  84% {
    opacity: 1;
    transform: translate(0, 26px) scale(1, 1);
  }
  86% {
    opacity: 0;
    transform: translate(0, 26px) scale(1, 1);
  }
  100% {
    opacity: 0;
    transform: translate(0, 26px) scale(1, 1);
  }
}
@keyframes rs-lit-a {
  0% {
    background: none;
  }
  10% {
    background: rgba(110, 200, 255, 0.22);
  }
  86% {
    background: none;
  }
  100% {
    background: none;
  }
}
@keyframes rs-s1 {
  0% {
    opacity: 0;
  }
  10% {
    opacity: 1;
  }
  26% {
    opacity: 0;
  }
  82% {
    opacity: 1;
  }
  86% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes rs-lit-b {
  0% {
    background: none;
  }
  26% {
    background: rgba(110, 200, 255, 0.22);
  }
  81% {
    background: none;
  }
  100% {
    background: none;
  }
}
@keyframes rs-lit-c {
  0% {
    background: none;
  }
  40% {
    background: rgba(110, 200, 255, 0.22);
  }
  78% {
    background: none;
  }
  100% {
    background: none;
  }
}
@keyframes rs-hide {
  0% {
    opacity: 1;
  }
  10% {
    opacity: 0;
  }
  88% {
    opacity: 1;
  }
  100% {
    opacity: 1;
  }
}
@keyframes rs-s2 {
  0% {
    opacity: 0;
  }
  26% {
    opacity: 1;
  }
  40% {
    opacity: 0;
  }
  78% {
    opacity: 1;
  }
  82% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes rs-s3 {
  0% {
    opacity: 0;
  }
  40% {
    opacity: 1;
  }
  78% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes rs-toast {
  0% {
    opacity: 0;
  }
  62% {
    opacity: 1;
  }
  80% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes rs-pop {
  0% {
    transform: translateY(10px);
  }
  62% {
    transform: translateY(10px);
  }
  70% {
    transform: translateY(0);
  }
  80% {
    transform: translateY(0);
  }
  100% {
    transform: translateY(0);
  }
}
@media (max-width: 340px) {
  .rs__foot {
    margin-top: 4px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .rs.is-demo .rs__box,
  .rs.is-demo .rs__row > b,
  .rs.is-demo .rs__s0,
  .rs.is-demo .rs__s1,
  .rs.is-demo .rs__s2,
  .rs.is-demo .rs__s3,
  .rs.is-demo .rs__toast,
  .rs.is-demo .rs__toast-in {
    animation: none !important;
  }
  .rs.is-demo .rs__box {
    opacity: 1;
    transform: translate(0, 26px) scale(3, 3);
  }
  .rs.is-demo .rs__s0 {
    opacity: 0;
  }
  .rs.is-demo .rs__s3 {
    opacity: 1;
  }
  .rs__row > * {
    transition: none;
  }
}

// 실제 동작: 셀에서 셀로 끌면 두 지점이 만드는 네모가 선택 범위다. 놓으면 탭으로 이어 붙여 복사한다.
var rs = document.getElementById('rs');
var rsGrid = document.getElementById('rs-grid');
var rsBox = document.getElementById('rs-box');
var rsFoot = document.getElementById('rs-foot');
var RS_W = 66, RS_H = 26;
var rsAnchor = null, rsOn = false;
function rsCells() { return [].slice.call(rsGrid.querySelectorAll('[data-r]')); }
function rsPaint(to) {
  var r0 = Math.min(rsAnchor.r, to.r), r1 = Math.max(rsAnchor.r, to.r);
  var c0 = Math.min(rsAnchor.c, to.c), c1 = Math.max(rsAnchor.c, to.c);
  var sum = 0, n = 0, text = [];
  rsCells().forEach(function (el) {
    var r = +el.dataset.r, c = +el.dataset.c;
    var inside = r >= r0 && r <= r1 && c >= c0 && c <= c1;
    el.classList.toggle('is-sel', inside);
    if (inside) { sum += +el.textContent; n++; }
  });
  rsBox.style.opacity = '1';
  rsBox.style.transform = 'translate(' + (c0 * RS_W) + 'px, ' + ((r0 + 1) * RS_H) + 'px) scale(' + (c1 - c0 + 1) + ', ' + (r1 - r0 + 1) + ')';
  rsFoot.querySelector('.rs__s0').textContent = n + 'マス · 合計 ' + sum;
  return text;
}
rsGrid.addEventListener('pointerdown', function (e) {
  var el = e.target.closest('[data-r]');
  if (!el) return;
  rs.classList.remove('is-demo');
  rsAnchor = { r: +el.dataset.r, c: +el.dataset.c };
  rsOn = true; rsPaint(rsAnchor);
});
rsGrid.addEventListener('pointermove', function (e) {
  if (!rsOn) return;
  var el = document.elementFromPoint(e.clientX, e.clientY);
  el = el && el.closest ? el.closest('[data-r]') : null;
  if (el) rsPaint({ r: +el.dataset.r, c: +el.dataset.c });
});
window.addEventListener('pointerup', function () {
  if (!rsOn) return;
  rsOn = false;
  var rows = {};
  rsCells().forEach(function (el) {
    if (!el.classList.contains('is-sel')) return;
    (rows[el.dataset.r] = rows[el.dataset.r] || []).push(el.textContent);
  });
  var text = Object.keys(rows).map(function (k) { return rows[k].join('\t'); }).join('\n');
  if (navigator.clipboard) { navigator.clipboard.writeText(text).catch(function () {}); }
  rs.classList.add('is-copied');
  setTimeout(function () { rs.classList.remove('is-copied'); }, 1200);
});

import { useEffect, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./CellRangeSelect.module.scss";

export type CellRangeSelectProps = {
  tableLabel?: string;
  /** 머리글 — 열 개수와 데이터 폭을 맞춘다 */
  head?: string[];
  /** 본문 숫자 */
  data?: number[][];
  hint?: string;
  cellWord?: string;
  cellsWord?: string;
  sumWord?: string;
  copiedLabel?: string;
  /** 자동 재생 루프 (갤러리용). 사람이 손대면 꺼진다 */
  demo?: boolean;
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
type PtrEvt = { clientX: number; clientY: number; target: any };
type Cell = { r: number; c: number };
type Rect = { r0: number; r1: number; c0: number; c1: number };

// 셀 한 칸의 크기 — 범위 네모를 scale 로 늘릴 때의 기준
const CELL_W = 66;
const CELL_H = 26;

function CopyIcon() {
  return (
    <svg viewBox="0 0 256 256" width="1em" height="1em" fill="currentColor">
      <g>
        <path d="M216 40v128h-48V88H88V40Z" opacity=".2" />
        <path d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z" />
      </g>
    </svg>
  );
}

// 이벤트가 떨어진 자리의 셀 좌표 — data-r · data-c 를 읽는다
function cellOf(node: any): Cell | null {
  const el = node && node.closest ? node.closest("[data-r]") : null;
  if (!el) return null;
  return { r: Number(el.getAttribute("data-r")), c: Number(el.getAttribute("data-c")) };
}

export default function CellRangeSelect({
  tableLabel = "Weekly sales",
  head = ["Mon", "Tue", "Wed", "Thu"],
  data = [
    [12, 18, 9, 24],
    [7, 15, 21, 6],
    [30, 11, 3, 17],
  ],
  hint = "Drag to select",
  cellWord = "cell",
  cellsWord = "cells",
  sumWord = "sum",
  copiedLabel = "Copied",
  demo = true,
  duration = 220,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#6ec8ff",
}: CellRangeSelectProps) {
  const [anchor, setAnchor] = useState<Cell | null>(null);
  const [sel, setSel] = useState<Rect | null>(null);
  const [dragging, setDragging] = useState(false);
  const [copied, setCopied] = useState(false);
  const [live, setLive] = useState(demo);

  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  const cls = [styles.root, live ? styles.isDemo : "", copied ? styles.isCopied : ""].join(" ");

  const inside = (r: number, c: number) =>
    !!sel && r >= sel.r0 && r <= sel.r1 && c >= sel.c0 && c <= sel.c1;

  // 놓는 순간 탭·줄바꿈으로 이어 붙여 클립보드에 넣는다
  useEffect(() => {
    if (!dragging) return;
    const up = () => {
      setDragging(false);
      if (!sel) return;
      const lines: string[] = [];
      for (let r = sel.r0; r <= sel.r1; r++) {
        lines.push(data[r].slice(sel.c0, sel.c1 + 1).map((n) => String(n)).join("\t"));
      }
      if (navigator.clipboard) navigator.clipboard.writeText(lines.join("\n")).catch(() => {});
      setCopied(true);
      window.setTimeout(() => setCopied(false), 1200);
    };
    window.addEventListener("pointerup", up);
    return () => window.removeEventListener("pointerup", up);
  }, [dragging, sel, data]);

  const paint = (from: Cell, to: Cell) => {
    setSel({
      r0: Math.min(from.r, to.r),
      r1: Math.max(from.r, to.r),
      c0: Math.min(from.c, to.c),
      c1: Math.max(from.c, to.c),
    });
  };

  const onDown = (e: PtrEvt) => {
    const cell = cellOf(e.target);
    if (!cell) return;
    setLive(false);
    setAnchor(cell);
    setDragging(true);
    paint(cell, cell);
  };

  const onMove = (e: PtrEvt) => {
    if (!dragging || !anchor) return;
    const cell = cellOf(document.elementFromPoint(e.clientX, e.clientY));
    if (cell) paint(anchor, cell);
  };

  let count = 0;
  let sum = 0;
  data.forEach((row, r) =>
    row.forEach((n, c) => {
      if (inside(r, c)) {
        count += 1;
        sum += n;
      }
    })
  );

  const fmt = (n: number, s: number) => `${n} ${n === 1 ? cellWord : cellsWord} · ${sumWord} ${s}`;

  const boxStyle: CSSProperties = sel
    ? {
        opacity: 1,
        transform: `translate(${sel.c0 * CELL_W}px, ${(sel.r0 + 1) * CELL_H}px) scale(${
          sel.c1 - sel.c0 + 1
        }, ${sel.r1 - sel.r0 + 1})`,
      }
    : {};

  return (
    <div className={cls} style={vars}>
      <div
        className={styles.grid}
        role="grid"
        aria-label={tableLabel}
        onPointerDown={onDown}
        onPointerMove={onMove}
      >
        <div className={[styles.row, styles.rowHead].join(" ")} role="row">
          {head.map((h) => (
            <span key={h} role="columnheader">
              {h}
            </span>
          ))}
        </div>
        {data.map((row, r) => (
          <div className={styles.row} role="row" key={r}>
            {row.map((n, c) => (
              <b
                key={c}
                data-r={r}
                data-c={c}
                role="gridcell"
                className={inside(r, c) ? styles.sel : ""}
              >
                {n}
              </b>
            ))}
          </div>
        ))}
        <div className={styles.box} style={boxStyle} aria-hidden="true" />
      </div>
      <p className={styles.foot} role="status">
        <span className={styles.s0}>{sel ? fmt(count, sum) : hint}</span>
        <span className={styles.s1}>{fmt(1, 12)}</span>
        <span className={styles.s2}>{fmt(4, 52)}</span>
        <span className={styles.s3}>{fmt(9, 126)}</span>
      </p>
      <span className={styles.toast} aria-hidden="true">
        <span className={styles.toastIn}>
          <span className={styles.ic}>
            <CopyIcon />
          </span>
          {copiedLabel}
        </span>
      </span>
    </div>
  );
}