// HUD controller: categorized collapsible layer list, per-feed status lines,
// LIVE/SCRUBBED chip.

const rows = new Map();

// Category scheme is owned here so HUD order is stable regardless of layer
// registration order. Categories collapsed-by-default are marked below.
const CATEGORY_ORDER = ['Space', 'Air', 'Sea', 'Earth & hazards', 'Context', 'Regional — Australia'];
const COLLAPSED_BY_DEFAULT = new Set(['Regional — Australia']);
const CATEGORY_BY_ID = {
  satellites: 'Space', 'sat-paths': 'Space', launches: 'Space',
  aircraft: 'Air', military: 'Air', 'aircraft-mil': 'Air',
  ships: 'Sea',
  quakes: 'Earth & hazards', fires: 'Earth & hazards', gdacs: 'Earth & hazards', nws: 'Earth & hazards',
  infra: 'Context', events: 'Context',
  rfs: 'Regional — Australia',
};

const sections = new Map(); // category → { body }

// Lazily create a category section, inserted in CATEGORY_ORDER position.
function sectionFor(category) {
  if (sections.has(category)) return sections.get(category);
  const wrap = document.createElement('div');
  wrap.className = 'cat';
  if (COLLAPSED_BY_DEFAULT.has(category)) wrap.classList.add('collapsed');
  const header = document.createElement('div');
  header.className = 'cat-header';
  header.innerHTML = `<span class="cat-chevron">▾</span><span class="cat-name"></span>`;
  header.querySelector('.cat-name').textContent = category;
  header.addEventListener('click', () => wrap.classList.toggle('collapsed'));
  const body = document.createElement('div');
  body.className = 'cat-body';
  wrap.appendChild(header);
  wrap.appendChild(body);

  // Insert before the existing section that is this one's immediate successor in
  // CATEGORY_ORDER (smallest index greater than ours), so DOM order stays stable
  // regardless of registration order. Unknown categories sort last.
  const container = document.getElementById('layers');
  const ord = (c) => { const i = CATEGORY_ORDER.indexOf(c); return i < 0 ? Infinity : i; };
  const myOrder = ord(category);
  let before = null, bestOrder = Infinity;
  for (const [cat, s] of sections) {
    const idx = ord(cat);
    if (idx > myOrder && idx < bestOrder) { bestOrder = idx; before = s.wrap; }
  }
  container.insertBefore(wrap, before);
  const rec = { wrap, body };
  sections.set(category, rec);
  return rec;
}

// Register a layer row. Returns a handle so callers can flip the checkbox.
// `category` is optional; a known id maps to a fixed category regardless.
export function addLayer(id, name, defaultOn, onToggle, category) {
  const cat = CATEGORY_BY_ID[id] || category || 'Other';
  const row = document.createElement('div');
  row.className = 'layer-row';
  row.innerHTML = `
    <label>
      <input type="checkbox" ${defaultOn ? 'checked' : ''} />
      <span class="dot" data-state="${defaultOn ? 'ok' : 'off'}"></span>
      <span class="lname"></span>
    </label>
    <div class="lstatus"></div>`;
  row.querySelector('.lname').textContent = name;
  const cb = row.querySelector('input');
  cb.addEventListener('change', () => onToggle(cb.checked));
  sectionFor(cat).body.appendChild(row);
  rows.set(id, row);
  return { setChecked: (v) => { cb.checked = v; } };
}

// Registered layer ids, in registration order (for URL-state serialization).
export function getLayerIds() {
  return [...rows.keys()];
}

// Is a layer's checkbox currently checked?
export function getLayerChecked(id) {
  const row = rows.get(id);
  return row ? row.querySelector('input').checked : false;
}

// Set a layer's checkbox AND fire its onToggle (replays a real user toggle),
// so restoring URL state actually shows/hides the layer. No-op if unchanged.
export function setLayerChecked(id, on) {
  const row = rows.get(id);
  if (!row) return;
  const cb = row.querySelector('input');
  if (cb.checked !== on) {
    cb.checked = on;
    cb.dispatchEvent(new Event('change'));
  }
}

// state ∈ 'ok' | 'warn' | 'err' | 'off'
export function setStatus(id, text, state = 'ok') {
  const row = rows.get(id);
  if (!row) return;
  row.querySelector('.lstatus').textContent = text;
  row.querySelector('.dot').dataset.state = state;
}

export function setLiveChip(isLive) {
  const chip = document.getElementById('live-chip');
  if (!chip) return;
  chip.textContent = isLive ? 'LIVE' : 'SCRUBBED';
  chip.title = isLive ? 'Clock is at wall-clock now' : 'Live layers paused — scrubbed off now';
  chip.dataset.state = isLive ? 'live' : 'scrub';
}

// Small fixed overlay for primitive picks (aircraft), which have no Cesium InfoBox.
export function showPickOverlay(title, rowPairs) {
  const el = document.getElementById('pick-overlay');
  if (!el) return;
  el.innerHTML =
    `<div class="po-close" role="button" aria-label="close">×</div>` +
    `<div class="po-title"></div>` +
    rowPairs.map(() => `<div class="po-row"><span></span><span></span></div>`).join('');
  el.querySelector('.po-title').textContent = title;
  const rowEls = el.querySelectorAll('.po-row');
  rowPairs.forEach(([k, v], i) => {
    const spans = rowEls[i].querySelectorAll('span');
    spans[0].textContent = k;
    spans[1].textContent = v;
  });
  el.querySelector('.po-close').addEventListener('click', hidePickOverlay);
  el.hidden = false;
}

export function hidePickOverlay() {
  const el = document.getElementById('pick-overlay');
  if (el) el.hidden = true;
}