02팀원 그리드 — 마지막 줄 인원을 계산해 외톨이 카드를 없애는 배치

<main class="stage">
<section class="grid" id="grid">
  <p class="grid__hint" id="gridHint">마지막 줄에 남는 인원을 계산해 외톨이 카드 없이 가운데로 모읍니다</p>
  <div class="grid__head" id="gridHead" role="list" aria-label="팀원 목록"></div>
  <div class="grid__tail" id="gridTail" role="list" aria-label="마지막 줄"></div>
  <p class="grid__meta"><span class="grid__chip" id="gridChip">n=8 · cols 4 · 나머지 0</span></p>
</section>
</main>

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

$duration: $dur-base;         // 300ms — 카드 팝인
$easing: $ease-pop;
$color: $subject-blue-deep;

@include stage($stage-yellow);

.grid {
  width: 100%;
  max-width: 420px;
  display: flex;
  flex-direction: column;
  gap: $sp-2;
  align-items: center;
  text-align: center;
}

.grid__hint {
  margin: 0;
  padding: 0 $sp-2;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba($subject-ink, .72);
}

.grid__head {
  display: grid;
  grid-template-columns: repeat(var(--cols, 4), 1fr);
  gap: $sp-2;
  width: 100%;
}

.grid__tail {
  display: flex;
  justify-content: center;
  gap: $sp-2;
  width: 100%;
}

.grid__card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: $sp-1;
  padding: $sp-2;
  border-radius: $r-control;
  background: rgba($subject-ink, .06);
  opacity: 0;
  transform: scale(.8);
  transition: opacity $dur-quick $ease-out, transform $duration $easing;
}

.grid.is-in .grid__card {
  opacity: 1;
  transform: scale(1);
}

.grid__cv {
  display: block;
  width: 28px;
  height: 28px;
  border-radius: $r-pill;
}

.grid__tag {
  font-weight: 500;
  font-size: 9px;
  color: rgba($subject-ink, .72);
}

.grid__meta { margin: 0; }

.grid__chip {
  display: inline-flex;
  padding: $sp-1 $sp-3;
  border-radius: $r-pill;
  background: $color;
  color: $subject-cream;
  font-weight: 700;
  font-size: 11px;
}

@media (max-width: 340px) {
  .grid { max-width: 300px; gap: $sp-1; }
  .grid__hint { font-size: 8px; line-height: 1.3; }
  .grid__head, .grid__tail { gap: $sp-1; }
  .grid__card { padding: 0; gap: 0; }
  .grid__cv { width: 18px; height: 18px; }
  .grid__tag { font-size: 7px; }
  .grid__chip { font-size: 9px; padding: 0 $sp-2; }
}

@media (prefers-reduced-motion: reduce) {
  .grid__card {
    transition: none;
    opacity: 1;
    transform: none;
  }
}

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);
}

.grid {
  width: 100%;
  max-width: 420px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: center;
  text-align: center;
}

.grid__hint {
  margin: 0;
  padding: 0 8px;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba(23, 20, 26, 0.72);
}

.grid__head {
  display: grid;
  grid-template-columns: repeat(var(--cols, 4), 1fr);
  gap: 8px;
  width: 100%;
}

.grid__tail {
  display: flex;
  justify-content: center;
  gap: 8px;
  width: 100%;
}

.grid__card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 8px;
  border-radius: 12px;
  background: rgba(23, 20, 26, 0.06);
  opacity: 0;
  transform: scale(0.8);
  transition: opacity 220ms ease-out, transform 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.grid.is-in .grid__card {
  opacity: 1;
  transform: scale(1);
}

.grid__cv {
  display: block;
  width: 28px;
  height: 28px;
  border-radius: 999px;
}

.grid__tag {
  font-weight: 500;
  font-size: 9px;
  color: rgba(23, 20, 26, 0.72);
}

.grid__meta {
  margin: 0;
}

.grid__chip {
  display: inline-flex;
  padding: 4px 12px;
  border-radius: 999px;
  background: #0a4fe8;
  color: #fff7e6;
  font-weight: 700;
  font-size: 11px;
}

@media (max-width: 340px) {
  .grid {
    max-width: 300px;
    gap: 4px;
  }
  .grid__hint {
    font-size: 8px;
    line-height: 1.3;
  }
  .grid__head, .grid__tail {
    gap: 4px;
  }
  .grid__card {
    padding: 0;
    gap: 0;
  }
  .grid__cv {
    width: 18px;
    height: 18px;
  }
  .grid__tag {
    font-size: 7px;
  }
  .grid__chip {
    font-size: 9px;
    padding: 0 8px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .grid__card {
    transition: none;
    opacity: 1;
    transform: none;
  }
}

// 팀원 그리드(02) — 인원수를 열 수로 나눈 나머지로 마지막 줄에 몇 명이 남는지 계산하고,
// 나머지가 1~2명일 때만 그 인원을 별도 flex 줄로 떼어 가운데로 모은다. ResizeObserver 로
// 컨테이너 폭이 바뀌어 열 수 자체가 바뀔 때도 같은 계산을 다시 돌린다(계산 한 겹).
(function () {
  var grid = document.getElementById('grid');
  var head = document.getElementById('gridHead');
  var tail = document.getElementById('gridTail');
  var chip = document.getElementById('gridChip');
  if (!grid || !head || !tail || !chip) return;
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  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 HEXES = ['#9fc9ec', '#93d9c0', '#b9a0ff', '#f6c6d3'];

  function drawAvatar(cv, seed, label) {
    var ctx = cv.getContext('2d');
    if (!ctx) return;
    var rnd = mulberry32(seed);
    var s = cv.width;
    ctx.clearRect(0, 0, s, s);
    ctx.save();
    ctx.beginPath(); ctx.arc(s / 2, s / 2, s / 2, 0, Math.PI * 2); ctx.clip();
    var cell = 6;
    for (var y = 0; y < s; y += cell) {
      for (var x = 0; x < s; x += cell) {
        var v = rnd();
        ctx.fillStyle = v > .5 ? HEXES[Math.floor(rnd() * HEXES.length)] : 'rgba(23,20,26,.08)';
        ctx.fillRect(x, y, cell, cell);
      }
    }
    ctx.restore();
    ctx.fillStyle = 'rgba(23,20,26,.55)';
    ctx.beginPath(); ctx.arc(s / 2, s / 2, s / 2, 0, Math.PI * 2); ctx.fill();
    ctx.fillStyle = '#fff7e6';
    ctx.font = '700 ' + Math.round(s * .4) + 'px -apple-system, "Segoe UI", sans-serif';
    ctx.textAlign = 'center'; ctx.textBaseline = 'middle';
    ctx.fillText(label, s / 2, s / 2 + 1);
  }

  function card(i) {
    var el = document.createElement('div');
    el.className = 'grid__card';
    el.setAttribute('role', 'listitem');
    var cv = document.createElement('canvas');
    cv.className = 'grid__cv'; cv.width = 28; cv.height = 28;
    cv.setAttribute('aria-hidden', 'true');
    var tag = document.createElement('span');
    tag.className = 'grid__tag';
    tag.textContent = 'M' + (i + 1);
    el.appendChild(cv); el.appendChild(tag);
    drawAvatar(cv, 11 + i * 13, 'M' + (i + 1));
    return el;
  }

  var cols = 4;   // 기본값 — ResizeObserver 가 실측 폭으로 다시 계산한다
  var MIN_CARD = 76;

  function computeCols(width) {
    var c = Math.floor(width / MIN_CARD);
    return Math.max(2, Math.min(5, c || 4));
  }

  function layout(count) {
    var remainder = count % cols;
    var tailCount = (remainder === 1 || remainder === 2) ? remainder : 0;
    var headCount = count - tailCount;
    head.style.setProperty('--cols', String(cols));
    head.innerHTML = '';
    tail.innerHTML = '';
    for (var i = 0; i < headCount; i++) head.appendChild(card(i));
    for (var j = 0; j < tailCount; j++) tail.appendChild(card(headCount + j));
    tail.style.display = tailCount > 0 ? 'flex' : 'none';
    chip.textContent = 'n=' + count + ' · cols ' + cols + ' · 나머지 ' + tailCount;
    grid.classList.remove('is-in');
    void grid.offsetWidth;
    grid.classList.add('is-in');
  }

  var ro = new ResizeObserver(function (entries) {
    var w = entries[0] ? entries[0].contentRect.width : grid.clientWidth;
    var next = computeCols(w);
    if (next !== cols) { cols = next; layout(counts[idx]); }
  });
  ro.observe(grid);

  var counts = [7, 8, 9, 10];
  var idx = 0;
  layout(counts[0]);

  if (!reduce) {
    setInterval(function () {
      idx = (idx + 1) % counts.length;
      layout(counts[idx]);
    }, 700);
  }
})();

// TeamMemberGrid — vanilla 판(run/338/demo/02-team-member-grid/index.html) 의 React 포트.
// 인원수를 열 수로 나눈 나머지로 마지막 줄에 몇 명이 남는지 계산하고, 나머지가 1~2명일 때만
// 그 인원을 별도 flex 줄로 떼어 가운데로 모은다. ResizeObserver 로 컨테이너 폭이 바뀌어 열 수
// 자체가 바뀔 때도 같은 계산을 다시 돌린다(계산 한 겹).
import { useEffect, useRef } from "react";
import styles from "./TeamMemberGrid.module.scss";

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

const HINT = "마지막 줄에 남는 인원을 계산해 외톨이 카드 없이 가운데로 모읍니다";
const HEAD_LABEL = "팀원 목록";
const TAIL_LABEL = "마지막 줄";

function mulberry32(a: number): () => number {
  return function (): number {
    a |= 0; a = a + 0x6d2b79f5 | 0;
    let t = Math.imul(a ^ (a >>> 15), 1 | a);
    t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
    return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
  };
}

const HEXES = ["#9fc9ec", "#93d9c0", "#b9a0ff", "#f6c6d3"];
const COUNTS = [7, 8, 9, 10];
const MIN_CARD = 76;

function drawAvatar(cv: HTMLCanvasElement, seed: number, label: string): void {
  const ctx = cv.getContext("2d");
  if (!ctx) return;
  const rnd = mulberry32(seed);
  const s = cv.width;
  ctx.clearRect(0, 0, s, s);
  ctx.save();
  ctx.beginPath();
  ctx.arc(s / 2, s / 2, s / 2, 0, Math.PI * 2);
  ctx.clip();
  const cell = 6;
  for (let y = 0; y < s; y += cell) {
    for (let x = 0; x < s; x += cell) {
      const v = rnd();
      ctx.fillStyle = v > 0.5 ? HEXES[Math.floor(rnd() * HEXES.length)] : "rgba(23,20,26,.08)";
      ctx.fillRect(x, y, cell, cell);
    }
  }
  ctx.restore();
  ctx.fillStyle = "rgba(23,20,26,.55)";
  ctx.beginPath();
  ctx.arc(s / 2, s / 2, s / 2, 0, Math.PI * 2);
  ctx.fill();
  ctx.fillStyle = "#fff7e6";
  ctx.font = "700 " + Math.round(s * 0.4) + 'px -apple-system, "Segoe UI", sans-serif';
  ctx.textAlign = "center";
  ctx.textBaseline = "middle";
  ctx.fillText(label, s / 2, s / 2 + 1);
}

function computeCols(width: number): number {
  const c = Math.floor(width / MIN_CARD);
  return Math.max(2, Math.min(5, c || 4));
}

function makeCard(i: number): HTMLDivElement {
  const el = document.createElement("div");
  el.className = styles.card;
  el.setAttribute("role", "listitem");
  const cv = document.createElement("canvas");
  cv.className = styles.cv;
  cv.width = 28;
  cv.height = 28;
  cv.setAttribute("aria-hidden", "true");
  const tag = document.createElement("span");
  tag.className = styles.tag;
  tag.textContent = "M" + (i + 1);
  el.appendChild(cv);
  el.appendChild(tag);
  drawAvatar(cv, 11 + i * 13, "M" + (i + 1));
  return el;
}

export default function TeamMemberGrid({
  duration = "300ms",
  easing = "cubic-bezier(.2,1.4,.4,1)",
  color = "#0a4fe8"
}: TeamMemberGridProps) {
  const gridRef = useRef<HTMLElement | null>(null);
  const headRef = useRef<HTMLDivElement | null>(null);
  const tailRef = useRef<HTMLDivElement | null>(null);
  const chipRef = useRef<HTMLSpanElement | null>(null);

  useEffect(() => {
    const grid = gridRef.current;
    const head = headRef.current;
    const tail = tailRef.current;
    const chip = chipRef.current;
    if (!grid || !head || !tail || !chip) return;
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;

    let cols = 4;
    let idx = 0;

    function layout(count: number): void {
      const remainder = count % cols;
      const tailCount = remainder === 1 || remainder === 2 ? remainder : 0;
      const headCount = count - tailCount;
      head!.style.setProperty("--cols", String(cols));
      head!.innerHTML = "";
      tail!.innerHTML = "";
      for (let i = 0; i < headCount; i++) head!.appendChild(makeCard(i));
      for (let j = 0; j < tailCount; j++) tail!.appendChild(makeCard(headCount + j));
      tail!.style.display = tailCount > 0 ? "flex" : "none";
      chip!.textContent = "n=" + count + " · cols " + cols + " · 나머지 " + tailCount;
      grid!.classList.remove(styles.gridIn);
      void grid!.offsetWidth;
      grid!.classList.add(styles.gridIn);
    }

    const ro = new ResizeObserver((entries) => {
      const w = entries[0] ? entries[0].contentRect.width : grid!.clientWidth;
      const next = computeCols(w);
      if (next !== cols) { cols = next; layout(COUNTS[idx]); }
    });
    ro.observe(grid);

    layout(COUNTS[0]);

    let timer = 0;
    if (!reduce) {
      timer = window.setInterval(() => {
        idx = (idx + 1) % COUNTS.length;
        layout(COUNTS[idx]);
      }, 700);
    }

    return () => {
      ro.disconnect();
      if (timer) window.clearInterval(timer);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  return (
    <main className={styles.stage}>
      <section className={styles.grid} ref={gridRef}>
        <p className={styles.hint}>{HINT}</p>
        <div className={styles.head} ref={headRef} role="list" aria-label={HEAD_LABEL} />
        <div className={styles.tail} ref={tailRef} role="list" aria-label={TAIL_LABEL} />
        <p className={styles.meta}>
          <span className={styles.chip} ref={chipRef} style={{ background: color }}>n=8 · cols 4 · 나머지 0</span>
        </p>
      </section>
    </main>
  );
}