09Grid to agenda fold

<main class="stage">
  <section class="ag is-demo" id="ag" aria-label="September schedule">
    <div class="ag__bar">
      <span class="ag__title">2026. 9</span>
      <span class="ag__toggl" role="group" aria-label="View switch">
        <button type="button" class="ag__btn" id="ag-bgrid" aria-label="Grid view" aria-pressed="false"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 256" width="14" height="14" aria-hidden="true"><g fill="currentColor"><path d="M112 56v48a8 8 0 0 1-8 8H56a8 8 0 0 1-8-8V56a8 8 0 0 1 8-8h48a8 8 0 0 1 8 8m88-8h-48a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8V56a8 8 0 0 0-8-8m-96 96H56a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8v-48a8 8 0 0 0-8-8m96 0h-48a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8v-48a8 8 0 0 0-8-8" opacity=".2"/><path d="M200 136h-48a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16v-48a16 16 0 0 0-16-16m0 64h-48v-48h48zM104 40H56a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16V56a16 16 0 0 0-16-16m0 64H56V56h48zm96-64h-48a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16V56a16 16 0 0 0-16-16m0 64h-48V56h48zm-96 32H56a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16v-48a16 16 0 0 0-16-16m0 64H56v-48h48z"/></g></svg></button>
        <button type="button" class="ag__btn" id="ag-blist" aria-label="List view" aria-pressed="true"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 256" width="14" height="14" aria-hidden="true"><g fill="currentColor"><path d="M216 64v128H88V64Z" opacity=".2"/><path d="M80 64a8 8 0 0 1 8-8h128a8 8 0 0 1 0 16H88a8 8 0 0 1-8-8m136 56H88a8 8 0 1 0 0 16h128a8 8 0 0 0 0-16m0 64H88a8 8 0 1 0 0 16h128a8 8 0 0 0 0-16M44 52a12 12 0 1 0 12 12a12 12 0 0 0-12-12m0 64a12 12 0 1 0 12 12a12 12 0 0 0-12-12m0 64a12 12 0 1 0 12 12a12 12 0 0 0-12-12"/></g></svg></button>
        <span class="ag__pill" aria-hidden="true"></span>
      </span>
    </div>
    <div class="ag__frame" id="ag-frame">
      <div class="ag__view" id="ag-view" role="grid" aria-label="September schedule grid" data-lgrid="September schedule grid" data-llist="September schedule list" data-wgrid="Grid" data-wlist="List">
        <div class="ag__grid" id="ag-grid">
          <div class="ag__wd" aria-hidden="true"><span>S</span><span>M</span><span>T</span><span>W</span><span>T</span><span>F</span><span>S</span></div>
          <div class="ag__rows" id="ag-rows"></div>
        </div>
        <div class="ag__list" id="ag-list">
          <div class="ag__item" role="listitem" tabindex="-1"><span class="ag__d">14</span><span class="ag__wdn">Monday</span><span class="ag__chips"><span class="ag__chip">Review</span><span class="ag__chip">Meeting</span></span></div>
          <div class="ag__item" role="listitem" tabindex="-1"><span class="ag__d">16</span><span class="ag__wdn">Wednesday</span><span class="ag__chips"><span class="ag__chip">Gym</span></span></div>
          <div class="ag__item" role="listitem" tabindex="-1"><span class="ag__d">18</span><span class="ag__wdn">Friday</span><span class="ag__chips"><span class="ag__chip">Clinic</span></span></div>
          <div class="ag__item" role="listitem" tabindex="-1"><span class="ag__d">21</span><span class="ag__wdn">Monday</span><span class="ag__chips"><span class="ag__chip">Retro</span></span></div>
          <div class="ag__item" role="listitem" tabindex="-1"><span class="ag__d">23</span><span class="ag__wdn">Wednesday</span><span class="ag__chips"><span class="ag__chip">Deploy</span></span></div>
        </div>
      </div>
    </div>
    <span class="ag__live" role="status" id="ag-live"></span>
  </section>
</main>

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

$duration: $dur-quick;
$easing:   $ease-out;
$color:    $subject-blue;    // 잉크 무대 위 크림 글자 + 파란 포인트

@include stage($stage-ink);

.ag {
  width: min(100%, 436px);
}

.ag__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: $sp-2;
  margin: 0 0 $sp-2;
}
.ag__title {
  font-size: clamp(13px, 3vw, 16px);
  line-height: 1;
  font-weight: 800;
  color: $subject-cream;
}

// 보기 표시 아이콘 — 활성 쪽만 진하다. 교체는 크로스페이드가 아니라 steps(1, end) 컷
.ag__toggl {
  position: relative;
  display: flex;
  gap: $sp-1;
  padding: $sp-1;
  border: 1px solid rgba(255, 255, 255, .14);
  background: rgba(255, 255, 255, .06);
  border-radius: $r-control;
}
.ag__btn {
  position: relative;
  z-index: 1;
  width: 28px;
  height: 20px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  background: none;
  border-radius: $r-xs;
  color: $subject-cream;
  opacity: .4;
  cursor: pointer;
  transition: opacity $duration steps(1, end), color $duration steps(1, end);
}
.ag__btn.is-on { opacity: 1; color: $color; }
.ag__btn:focus-visible { outline: 2px solid $color; outline-offset: 1px; }
.ag__pill {
  position: absolute;
  top: $sp-1;
  left: $sp-1;
  width: 28px;
  height: 20px;
  border: 1px solid $color;
  border-radius: $r-xs;
  pointer-events: none;
  transition: transform $duration steps(1, end);
}
.ag.is-agenda .ag__pill { transform: translateX(32px); }

// 칩: @container — 이 상자의 폭이 좁아지면 격자가 아젠다로 접힌다
.ag__frame {
  container-type: inline-size;
  position: relative;
  box-sizing: border-box;
  width: var(--fw, 100%);
  height: clamp(132px, 58vh, 174px);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, .14);
  background: rgba(255, 255, 255, .04);
  border-radius: $r-card;
  transition: width $dur-base $ease-spring;
}

.ag__view {
  position: absolute;
  inset: 0;
}

.ag__grid {
  display: flex;
  flex-direction: column;
  height: 100%;
  box-sizing: border-box;
}
.ag__list {
  display: none;
  flex-direction: column;
  height: 100%;
  box-sizing: border-box;
  margin: 0;
  padding: $sp-2;
  list-style: none;
}

@container (max-width: 176px) {
  .ag__grid { display: none; }
  .ag__list { display: flex; }
}

// ── 격자 보기 ──
.ag__wd {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  padding: $sp-2 $sp-2 0;
  color: color.mix($subject-cream, transparent, 72%);   // 45% 는 4.21:1 이었다 — AA 4.5 (8.65:1)
  font-size: clamp(8px, 1.8vw, 10px);
  line-height: 1.2;
  font-weight: 600;
  text-align: center;
}
.ag__rows {
  flex: 1 1 0;
  min-height: 0;
  display: grid;
  grid-template-rows: repeat(5, 1fr);
  padding: $sp-1 $sp-2 $sp-2;
}
.ag__row {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
}
.ag__cell {
  position: relative;
  display: grid;
  place-items: center;
  border-radius: $r-xs;
  font-size: clamp(10px, 2.4vw, 13px);
  line-height: 1;
  font-weight: 500;
  color: color.mix($subject-cream, transparent, 82%);
  cursor: pointer;
}
.ag__cell.is-today {
  color: $subject-cream;
  font-weight: 800;
  box-shadow: inset 0 0 0 2px $color;
}
.ag__cell:focus-visible { outline: 2px solid $color; outline-offset: 1px; }
.ag__dot {
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: $color;
}

// ── 아젠다 보기 — 접힐 때 한 줄씩 올라온다 (translateY) ──
.ag__item {
  flex: 1 1 0;
  min-height: 0;
  display: flex;
  align-items: center;
  gap: $sp-2;
  padding: 0 $sp-2;
  border-radius: $r-sm;
  animation-name: ag-rise;
  animation-duration: $duration;
  animation-timing-function: $easing;
  animation-fill-mode: backwards;
}
// 줄 시차 — 낱개 속성 (animation 단축은 delay 를 0s 로 리셋한다)
.ag__item:nth-child(2) { animation-delay: 40ms; }
.ag__item:nth-child(3) { animation-delay: 80ms; }
.ag__item:nth-child(4) { animation-delay: 120ms; }
.ag__item:nth-child(5) { animation-delay: 160ms; }
@keyframes ag-rise {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.ag__item:focus-visible { outline: 2px solid $color; outline-offset: -2px; }
.ag__d {
  font-size: clamp(14px, 3.2vw, 18px);
  line-height: 1;
  font-weight: 800;
  color: $subject-cream;
}
.ag__wdn {
  min-width: 44px;
  font-size: clamp(9px, 2vw, 11px);
  line-height: 1;
  font-weight: 600;
  color: color.mix($subject-cream, transparent, 55%);
}
.ag__chips {
  display: flex;
  gap: $sp-1;
  min-width: 0;
  overflow: hidden;
}
.ag__chip {
  display: inline-flex;
  align-items: center;
  gap: $sp-1;
  height: 18px;
  padding: 0 $sp-2;
  border-radius: $r-pill;
  background: color.mix($color, transparent, 24%);
  color: $subject-cream;
  font-size: clamp(8px, 1.9vw, 10px);
  line-height: 1;
  font-weight: 600;
  white-space: nowrap;
}
.ag__chip::before {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: $color;
}

.ag__live {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
}

// ── 자동 루프: 컨테이너 폭을 오간다 — 아젠다 → 펴져 격자 → 다시 접힌다.
//    0% 와 100% 가 같은 폭(34%)이라 이어 붙여도 텔레포트가 없다.
.ag.is-demo .ag__frame {
  animation-name: ag-fold;
  animation-duration: $dur-loop;
  animation-timing-function: $ease-spring;
  animation-iteration-count: infinite;
}
@keyframes ag-fold {
  0%, 6%     { width: 34%; }
  24%, 54%   { width: 100%; }
  72%, 100%  { width: 34%; }
}

@media (prefers-reduced-motion: reduce) {
  .ag.is-demo .ag__frame { animation: none !important; }
  .ag__item { animation: none !important; }
  .ag__btn, .ag__pill, .ag__frame { 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);
}

.ag {
  width: min(100%, 436px);
}

.ag__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin: 0 0 8px;
}

.ag__title {
  font-size: clamp(13px, 3vw, 16px);
  line-height: 1;
  font-weight: 800;
  color: #fff7e6;
}

.ag__toggl {
  position: relative;
  display: flex;
  gap: 4px;
  padding: 4px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
  border-radius: 12px;
}

.ag__btn {
  position: relative;
  z-index: 1;
  width: 28px;
  height: 20px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  background: none;
  border-radius: 4px;
  color: #fff7e6;
  opacity: 0.4;
  cursor: pointer;
  transition: opacity 220ms steps(1, end), color 220ms steps(1, end);
}

.ag__btn.is-on {
  opacity: 1;
  color: #2f6df6;
}

.ag__btn:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: 1px;
}

.ag__pill {
  position: absolute;
  top: 4px;
  left: 4px;
  width: 28px;
  height: 20px;
  border: 1px solid #2f6df6;
  border-radius: 4px;
  pointer-events: none;
  transition: transform 220ms steps(1, end);
}

.ag.is-agenda .ag__pill {
  transform: translateX(32px);
}

.ag__frame {
  container-type: inline-size;
  position: relative;
  box-sizing: border-box;
  width: var(--fw, 100%);
  height: clamp(132px, 58vh, 174px);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.04);
  border-radius: 16px;
  transition: width 300ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.ag__view {
  position: absolute;
  inset: 0;
}

.ag__grid {
  display: flex;
  flex-direction: column;
  height: 100%;
  box-sizing: border-box;
}

.ag__list {
  display: none;
  flex-direction: column;
  height: 100%;
  box-sizing: border-box;
  margin: 0;
  padding: 8px;
  list-style: none;
}

@container (max-width: 176px) {
  .ag__grid {
    display: none;
  }
  .ag__list {
    display: flex;
  }
}
.ag__wd {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  padding: 8px 8px 0;
  color: rgba(255, 247, 230, 0.72);
  font-size: clamp(8px, 1.8vw, 10px);
  line-height: 1.2;
  font-weight: 600;
  text-align: center;
}

.ag__rows {
  flex: 1 1 0;
  min-height: 0;
  display: grid;
  grid-template-rows: repeat(5, 1fr);
  padding: 4px 8px 8px;
}

.ag__row {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
}

.ag__cell {
  position: relative;
  display: grid;
  place-items: center;
  border-radius: 4px;
  font-size: clamp(10px, 2.4vw, 13px);
  line-height: 1;
  font-weight: 500;
  color: rgba(255, 247, 230, 0.82);
  cursor: pointer;
}

.ag__cell.is-today {
  color: #fff7e6;
  font-weight: 800;
  box-shadow: inset 0 0 0 2px #2f6df6;
}

.ag__cell:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: 1px;
}

.ag__dot {
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: #2f6df6;
}

.ag__item {
  flex: 1 1 0;
  min-height: 0;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 8px;
  border-radius: 8px;
  animation-name: ag-rise;
  animation-duration: 220ms;
  animation-timing-function: ease-out;
  animation-fill-mode: backwards;
}

.ag__item:nth-child(2) {
  animation-delay: 40ms;
}

.ag__item:nth-child(3) {
  animation-delay: 80ms;
}

.ag__item:nth-child(4) {
  animation-delay: 120ms;
}

.ag__item:nth-child(5) {
  animation-delay: 160ms;
}

@keyframes ag-rise {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.ag__item:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: -2px;
}

.ag__d {
  font-size: clamp(14px, 3.2vw, 18px);
  line-height: 1;
  font-weight: 800;
  color: #fff7e6;
}

.ag__wdn {
  min-width: 44px;
  font-size: clamp(9px, 2vw, 11px);
  line-height: 1;
  font-weight: 600;
  color: rgba(255, 247, 230, 0.55);
}

.ag__chips {
  display: flex;
  gap: 4px;
  min-width: 0;
  overflow: hidden;
}

.ag__chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  height: 18px;
  padding: 0 8px;
  border-radius: 999px;
  background: rgba(47, 109, 246, 0.24);
  color: #fff7e6;
  font-size: clamp(8px, 1.9vw, 10px);
  line-height: 1;
  font-weight: 600;
  white-space: nowrap;
}

.ag__chip::before {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: #2f6df6;
}

.ag__live {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
}

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

@keyframes ag-fold {
  0%, 6% {
    width: 34%;
  }
  24%, 54% {
    width: 100%;
  }
  72%, 100% {
    width: 34%;
  }
}
@media (prefers-reduced-motion: reduce) {
  .ag.is-demo .ag__frame {
    animation: none !important;
  }
  .ag__item {
    animation: none !important;
  }
  .ag__btn, .ag__pill, .ag__frame {
    transition: none;
  }
}

// 실제 동작: 같은 날짜 데이터가 넓으면 7열 Grid, 좁으면 아젠다.
// @container 가 보기를 고르고 ResizeObserver 가 role(grid/list)·아이콘·포커스를 실제로 바꾼다.
var root = document.getElementById('ag');
var frame = document.getElementById('ag-frame');
var view = document.getElementById('ag-view');
var rowsBox = document.getElementById('ag-rows');
var list = document.getElementById('ag-list');
var live = document.getElementById('ag-live');
var bgrid = document.getElementById('ag-bgrid');
var blist = document.getElementById('ag-blist');
var EVENTS = { 14: 1, 16: 1, 18: 1, 21: 1, 23: 1 };
var TODAY = 12;

var cells = [];
var lead = new Date(2026, 8, 1).getDay();    // 2 (T)
for (var r = 0; r < 5; r++) {
  var row = document.createElement('div');
  row.className = 'ag__row';
  row.setAttribute('role', 'row');
  for (var c = 0; c < 7; c++) {
    var day = r * 7 + c - lead + 1;
    var cell = document.createElement('span');
    cell.className = 'ag__cell';
    if (day < 1 || day > 30) {
      cell.setAttribute('aria-hidden', 'true');
    } else {
      cell.setAttribute('role', 'gridcell');
      cell.setAttribute('aria-label', '2026-09-' + (day < 10 ? '0' + day : day));
      cell.tabIndex = -1;
      cell.textContent = day;
      if (EVENTS[day]) {
        var dot = document.createElement('i');
        dot.className = 'ag__dot';
        cell.appendChild(dot);
      }
      if (day === TODAY) { cell.classList.add('is-today'); cell.setAttribute('aria-current', 'date'); }
      cells.push(cell);
    }
    row.appendChild(cell);
  }
  rowsBox.appendChild(row);
}
var items = [].slice.call(list.children);
cells[0].tabIndex = 0;
items[0].tabIndex = 0;

var isAgenda = null;
function focusFirst() {
  var pool = isAgenda ? items : cells;
  pool.forEach(function (x) { x.tabIndex = -1; });
  pool[0].tabIndex = 0;
  pool[0].focus({ preventScroll: true });
}
function setMode(narrow) {
  if (narrow === isAgenda) return;
  isAgenda = narrow;
  root.classList.toggle('is-agenda', narrow);
  view.setAttribute('role', narrow ? 'list' : 'grid');
  view.setAttribute('aria-label', narrow ? view.dataset.llist : view.dataset.lgrid);
  bgrid.classList.toggle('is-on', !narrow);
  blist.classList.toggle('is-on', narrow);
  bgrid.setAttribute('aria-pressed', String(!narrow));
  blist.setAttribute('aria-pressed', String(narrow));
  live.textContent = narrow ? view.dataset.wlist : view.dataset.wgrid;
  var a = document.activeElement;
  if (!a || a === document.body || !a.offsetParent) focusFirst();   // 숨겨진 칸에 있으면 새 보기 첫 칸으로
}
new ResizeObserver(function () { setMode(frame.getBoundingClientRect().width <= 176); }).observe(frame);

function pick(narrow, el) {                   // 아이콘 버튼 — 폭을 직접 오긴다 (전환이 눈에 보인다)
  root.classList.remove('is-demo');
  frame.style.setProperty('--fw', narrow ? '34%' : '100%');
  el.focus({ preventScroll: true });
}
bgrid.addEventListener('click', function () { pick(false, bgrid); });
blist.addEventListener('click', function () { pick(true, blist); });

var cur = 0, curI = 0;
root.addEventListener('keydown', function (e) {
  var k = e.key, n = null;
  root.classList.remove('is-demo');
  if (isAgenda) {                             // 리스트 축 — ±1
    if (k === 'ArrowDown') n = Math.min(curI + 1, items.length - 1);
    else if (k === 'ArrowUp') n = Math.max(curI - 1, 0);
    else if (k === 'Home') n = 0;
    else if (k === 'End') n = items.length - 1;
    if (n !== null && n !== curI) {
      e.preventDefault();
      items[curI].tabIndex = -1; curI = n; items[curI].tabIndex = 0;
      items[curI].focus({ preventScroll: true });
      live.textContent = '9.' + items[curI].querySelector('.ag__d').textContent;
    }
  } else {                                    // Grid 축 — ±1S / ±7S
    if (k === 'ArrowRight') n = Math.min(cur + 1, cells.length - 1);
    else if (k === 'ArrowLeft') n = Math.max(cur - 1, 0);
    else if (k === 'ArrowDown') n = Math.min(cur + 7, cells.length - 1);
    else if (k === 'ArrowUp') n = Math.max(cur - 7, 0);
    else if (k === 'Home') n = 0;
    else if (k === 'End') n = cells.length - 1;
    if (n !== null && n !== cur) {
      e.preventDefault();
      cells[cur].tabIndex = -1; cur = n; cells[cur].tabIndex = 0;
      cells[cur].focus({ preventScroll: true });
      live.textContent = cells[cur].getAttribute('aria-label');
    }
  }
});
rowsBox.addEventListener('click', function (e) {
  var t = e.target.closest ? e.target.closest('.ag__cell') : null;
  if (!t) return;
  root.classList.remove('is-demo');
  for (var i = 0; i < cells.length; i++) if (cells[i] === t) {
    cells[cur].tabIndex = -1; cur = i; cells[cur].tabIndex = 0;
    cells[cur].focus({ preventScroll: true });
    break;
  }
});
list.addEventListener('click', function (e) {
  var t = e.target.closest ? e.target.closest('.ag__item') : null;
  if (!t) return;
  root.classList.remove('is-demo');
  for (var i = 0; i < items.length; i++) if (items[i] === t) {
    items[curI].tabIndex = -1; curI = i; items[curI].tabIndex = 0;
    items[curI].focus({ preventScroll: true });
    break;
  }
});

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

export type AgendaSwitchCalendarProps = {
  demo?: boolean;
  duration?: number;   // 전환(폭)·줄 올라옴 길이 ms
  easing?: string;
  color?: string;      // 포인트 색 (아이콘·칩·오늘 링)
  rows?: { day: number; weekday: string; chips: string[] }[];
};

type KeyEvt = { key: string; preventDefault: () => void };
type PtrEvt = { currentTarget: HTMLElement };
type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };

const DEFAULT_ROWS = [
  { day: 14, weekday: "월요일", chips: ["리뷰", "미팅"] },
  { day: 16, weekday: "수요일", chips: ["운동"] },
  { day: 18, weekday: "금요일", chips: ["병원"] },
  { day: 21, weekday: "월요일", chips: ["회고"] },
  { day: 23, weekday: "수요일", chips: ["배포"] },
];

function pad(n: number): string {
  return n < 10 ? "0" + n : "" + n;
}

export default function AgendaSwitchCalendar({
  demo = true,
  duration = 220,
  easing = "ease-out",
  color = "#2f6df6",
  rows = DEFAULT_ROWS,
}: AgendaSwitchCalendarProps) {
  const [demoOn, setDemoOn] = useState(demo);
  const [agenda, setAgenda] = useState(false);   // @container 결과를 따라간다
  const [fw, setFw] = useState("100%");
  const [cur, setCur] = useState(0);
  const [curI, setCurI] = useState(0);
  const [ann, setAnn] = useState("");
  const frameRef = useRef<HTMLDivElement>(null);
  const cellRefs = useRef<(HTMLSpanElement | null)[]>([]);
  const itemRefs = useRef<(HTMLDivElement | null)[]>([]);

  const days = useMemo(() => {
    const eventDays: Record<number, number> = {};
    rows.forEach((r) => { eventDays[r.day] = r.chips.length; });
    const out: { day: number; label: string; events: number }[] = [];
    const lead = new Date(2026, 8, 1).getDay();      // 9월 1일 = 화요일
    const total = 30;
    for (let i = 0; i < 35; i++) {
      const day = i - lead + 1;
      if (day < 1 || day > total) continue;
      out.push({ day, label: "2026-09-" + pad(day), events: eventDays[day] || 0 });
    }
    return out;
  }, [rows]);

  // @container (max-width: 176px) 와 같은 조건을 ResizeObserver 로 — role 도 실제로 바꾼다
  useEffect(() => {
    const frame = frameRef.current;
    if (!frame || typeof ResizeObserver === "undefined") return;
    const ro = new ResizeObserver(() => {
      setAgenda(frame.getBoundingClientRect().width <= 176);
    });
    ro.observe(frame);
    return () => ro.disconnect();
  }, []);

  // 보기가 바뀌어 포커스가 숨겨진 칸에 남으면 새 보기의 첫 칸으로
  useEffect(() => {
    const a = document.activeElement;
    if (!a || a === document.body || !(a as HTMLElement).offsetParent) {
      const pool = (agenda ? itemRefs.current : cellRefs.current) || [];
      const first = pool[0];
      if (first) first.focus({ preventScroll: true });
    }
  }, [agenda]);

  function moveCell(i: number) {
    setDemoOn(false);
    setCur(i);
    const el = cellRefs.current ? cellRefs.current[i] : null;
    if (el) el.focus({ preventScroll: true });
    setAnn(days[i].label);
  }
  function moveItem(i: number) {
    setDemoOn(false);
    setCurI(i);
    const el = itemRefs.current ? itemRefs.current[i] : null;
    if (el) el.focus({ preventScroll: true });
    setAnn("9." + rows[i].day);
  }
  function pick(narrow: boolean) {
    setDemoOn(false);
    setFw(narrow ? "34%" : "100%");   // 폭을 직접 오긴다 — 전환이 눈에 보인다
  }
  function onKey(e: KeyEvt) {
    setDemoOn(false);
    let n: number | null = null;
    if (agenda) {                            // 리스트 축 — ±1
      if (e.key === "ArrowDown") n = Math.min(curI + 1, rows.length - 1);
      else if (e.key === "ArrowUp") n = Math.max(curI - 1, 0);
      else if (e.key === "Home") n = 0;
      else if (e.key === "End") n = rows.length - 1;
      if (n !== null && n !== curI) { e.preventDefault(); moveItem(n); }
    } else {                                 // 격자 축 — ±1일 / ±7일
      if (e.key === "ArrowRight") n = Math.min(cur + 1, days.length - 1);
      else if (e.key === "ArrowLeft") n = Math.max(cur - 1, 0);
      else if (e.key === "ArrowDown") n = Math.min(cur + 7, days.length - 1);
      else if (e.key === "ArrowUp") n = Math.max(cur - 7, 0);
      else if (e.key === "Home") n = 0;
      else if (e.key === "End") n = days.length - 1;
      if (n !== null && n !== cur) { e.preventDefault(); moveCell(n); }
    }
  }

  const vars: Vars = { "--duration": duration + "ms", "--easing": easing, "--color": color };

  return (
    <section
      className={`${styles.ag} ${demoOn ? styles.demo : ""} ${agenda ? styles.isAgenda : ""}`}
      style={vars}
      aria-label="9월 일정"
      onKeyDown={onKey}
      onPointerDown={() => setDemoOn(false)}
    >
      <div className={styles.bar}>
        <span className={styles.title}>2026. 9</span>
        <span className={styles.toggl} role="group" aria-label="보기 전환">
          <button
            type="button"
            className={`${styles.btn} ${!agenda ? styles.on : ""}`}
            aria-label="격자 보기"
            aria-pressed={!agenda}
            onClick={() => pick(false)}
          >
            <svg viewBox="0 0 256 256" width="14" height="14" aria-hidden="true"><g fill="currentColor"><path d="M112 56v48a8 8 0 0 1-8 8H56a8 8 0 0 1-8-8V56a8 8 0 0 1 8-8h48a8 8 0 0 1 8 8m88-8h-48a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8V56a8 8 0 0 0-8-8m-96 96H56a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8v-48a8 8 0 0 0-8-8m96 0h-48a8 8 0 0 0-8 8v48a8 8 0 0 0 8 8h48a8 8 0 0 0 8-8v-48a8 8 0 0 0-8-8" opacity=".2"/><path d="M200 136h-48a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16v-48a16 16 0 0 0-16-16m0 64h-48v-48h48zM104 40H56a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16V56a16 16 0 0 0-16-16m0 64H56V56h48zm96-64h-48a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16V56a16 16 0 0 0-16-16m0 64h-48V56h48zm-96 32H56a16 16 0 0 0-16 16v48a16 16 0 0 0 16 16h48a16 16 0 0 0 16-16v-48a16 16 0 0 0-16-16m0 64H56v-48h48z"/></g></svg>
          </button>
          <button
            type="button"
            className={`${styles.btn} ${agenda ? styles.on : ""}`}
            aria-label="목록 보기"
            aria-pressed={agenda}
            onClick={() => pick(true)}
          >
            <svg viewBox="0 0 256 256" width="14" height="14" aria-hidden="true"><g fill="currentColor"><path d="M216 64v128H88V64Z" opacity=".2"/><path d="M80 64a8 8 0 0 1 8-8h128a8 8 0 0 1 0 16H88a8 8 0 0 1-8-8m136 56H88a8 8 0 1 0 0 16h128a8 8 0 0 0 0-16m0 64H88a8 8 0 1 0 0 16h128a8 8 0 0 0 0-16M44 52a12 12 0 1 0 12 12a12 12 0 0 0-12-12m0 64a12 12 0 1 0 12 12a12 12 0 0 0-12-12m0 64a12 12 0 1 0 12 12a12 12 0 0 0-12-12"/></g></svg>
          </button>
          <span className={styles.pill} aria-hidden="true" />
        </span>
      </div>
      <div className={styles.frame} ref={frameRef} style={{ width: fw }}>
        {/* role 는 보기에 따라 실제로 바뀐다 — grid ↔ list */}
        <div
          className={styles.view}
          role={agenda ? "list" : "grid"}
          aria-label={agenda ? "9월 일정 목록" : "9월 일정 격자"}
        >
          <div className={styles.grid}>
            <div className={styles.wd} aria-hidden="true">
              {["일", "월", "화", "수", "목", "금", "토"].map((w, i) => <span key={i}>{w}</span>)}
            </div>
            <div className={styles.rows}>
              {[0, 1, 2, 3, 4].map((r) => (
                <div key={r} className={styles.row} role="row">
                  {[0, 1, 2, 3, 4, 5, 6].map((c) => {
                    const i = r * 7 + c - 2;   // 9월 1일 = 화요일(lead 2)
                    const d = i >= 0 && i < days.length ? days[i] : null;
                    if (!d) return <span key={c} aria-hidden="true" />;
                    const idx = days.indexOf(d);
                    return (
                      <span
                        key={c}
                        ref={(el: HTMLSpanElement | null) => { if (cellRefs.current) cellRefs.current[idx] = el; }}
                        className={`${styles.cell} ${d.day === 12 ? styles.today : ""}`}
                        role="gridcell"
                        aria-label={d.label}
                        aria-current={d.day === 12 ? "date" : undefined}
                        tabIndex={cur === idx ? 0 : -1}
                        onClick={() => moveCell(idx)}
                      >
                        {d.day}
                        {d.events > 0 && <i className={styles.dot} aria-hidden="true" />}
                      </span>
                    );
                  })}
                </div>
              ))}
            </div>
          </div>
          <div className={styles.list}>
            {rows.map((r, i) => (
              <div
                key={r.day}
                ref={(el: HTMLDivElement | null) => { if (itemRefs.current) itemRefs.current[i] = el; }}
                className={styles.item}
                role="listitem"
                tabIndex={curI === i ? 0 : -1}
                style={{ animationDelay: i * 40 + "ms" }}
                onClick={(e: PtrEvt) => { void e; moveItem(i); }}
              >
                <span className={styles.d}>{r.day}</span>
                <span className={styles.wdn}>{r.weekday}</span>
                <span className={styles.chips}>
                  {r.chips.map((chip) => (
                    <span key={chip} className={styles.chip}>{chip}</span>
                  ))}
                </span>
              </div>
            ))}
          </div>
        </div>
      </div>
      <span className={styles.live} role="status">{ann}</span>
    </section>
  );
}