// Radio Garden layer (Wave 6) — ~8,000 live radio stations pinned to their real
// cities. Click a dot → pick a station → it streams live through a small player.
// Place/channel JSON comes via the same-origin proxy (proxy/rg/…, no CORS
// upstream); the AUDIO itself streams straight from radio.garden — <audio> media
// loads don't need CORS. Unofficial API: default-off, fails soft.

export default function create(ctx) {
  const { viewer, Cesium, lib, ui } = ctx;
  const pts = viewer.scene.primitives.add(new Cesium.PointPrimitiveCollection());
  pts.show = false;

  let enabled = false;
  let loaded = false;
  const MINT = Cesium.Color.fromCssColorString('#7de3a0').withAlpha(0.85);
  const OUTLINE = Cesium.Color.BLACK;

  ui.addLayer('radio', 'Radio Garden (live radio)', false, (on) => {
    enabled = on;
    pts.show = on;
    if (on && !loaded) load();
    if (!on) { stopAudio(); hidePlayer(); ui.setStatus('radio', '', 'ok'); }
    else if (loaded) ui.setStatus('radio', `${pts.length} stations · click to listen`, 'ok');
  });

  async function load() {
    ui.setStatus('radio', 'loading stations…', 'warn');
    let res;
    try {
      res = await fetch('proxy/rg/ara/content/places', { cache: 'no-store' });
    } catch {
      ui.setStatus('radio', 'network error', 'err'); return;
    }
    if (!res.ok) { ui.setStatus('radio', `HTTP ${res.status}`, 'err'); return; }
    let list;
    try {
      list = (await res.json()).data.list;
    } catch {
      ui.setStatus('radio', 'bad response', 'err'); return;
    }
    for (const p of list) {
      const g = p.geo; // [lon, lat]
      if (!Array.isArray(g) || !isFinite(g[0]) || !isFinite(g[1])) continue;
      pts.add({
        position: Cesium.Cartesian3.fromDegrees(g[0], g[1]),
        pixelSize: 4,
        color: MINT,
        outlineColor: OUTLINE,
        outlineWidth: 1,
        disableDepthTestDistance: 50000,
        id: { layer: 'radio', placeId: p.url.split('/').pop(), title: p.title, country: p.country, size: p.size },
      });
    }
    loaded = true;
    if (enabled) ui.setStatus('radio', `${pts.length} stations · click to listen`, 'ok');
  }

  // ---- player ----
  const audio = new Audio();
  audio.volume = 0.85;
  let panel = null;
  let playingBtn = null;

  function ensurePanel() {
    if (panel) return panel;
    panel = document.createElement('aside');
    panel.id = 'radio-player';
    panel.hidden = true;
    panel.innerHTML = `<div class="rp-head"><span class="rp-title"></span><span class="rp-close" title="Close & stop">×</span></div>
      <div class="rp-list"></div>
      <div class="rp-foot">radio.garden · streams are live</div>`;
    panel.querySelector('.rp-close').addEventListener('click', () => { stopAudio(); hidePlayer(); });
    document.body.appendChild(panel);
    return panel;
  }

  function stopAudio() {
    audio.pause();
    audio.removeAttribute('src');
    audio.load();
    if (playingBtn) { playingBtn.textContent = '▶'; playingBtn = null; }
  }
  function hidePlayer() { if (panel) panel.hidden = true; }

  async function openPlayer(meta) {
    const p = ensurePanel();
    p.querySelector('.rp-title').textContent = `📻 ${meta.title}${meta.country ? ' · ' + meta.country : ''}`;
    const listEl = p.querySelector('.rp-list');
    listEl.innerHTML = '<div class="rp-hint">tuning…</div>';
    p.hidden = false;
    let items = [];
    try {
      const res = await fetch(`proxy/rg/ara/content/page/${encodeURIComponent(meta.placeId)}/channels`, { cache: 'no-store' });
      const j = await res.json();
      for (const block of (j.data && j.data.content) || []) {
        for (const it of block.items || []) {
          const pg = it.page || it;
          if (pg && pg.url && pg.title) items.push({ id: pg.url.split('/').pop(), title: pg.title });
        }
      }
    } catch { /* fall through to empty-state */ }
    if (!items.length) { listEl.innerHTML = '<div class="rp-hint">no stations found</div>'; return; }
    listEl.innerHTML = '';
    for (const st of items.slice(0, 14)) {
      const row = document.createElement('div');
      row.className = 'rp-row';
      const btn = document.createElement('button');
      btn.className = 'rp-play';
      btn.textContent = '▶';
      const name = document.createElement('span');
      name.textContent = st.title; // textContent — no HTML injection possible
      btn.addEventListener('click', () => {
        if (playingBtn === btn) { stopAudio(); return; } // toggle off
        stopAudio();
        // The mp3 endpoint 302s to the real stream; <audio> follows it, no CORS needed.
        audio.src = `https://radio.garden/api/ara/content/listen/${st.id}/channel.mp3`;
        audio.play().catch(() => { btn.textContent = '✕'; });
        btn.textContent = '■';
        playingBtn = btn;
      });
      row.appendChild(btn);
      row.appendChild(name);
      listEl.appendChild(row);
    }
  }

  function handlePick(picked) {
    if (!enabled || picked?.id?.layer !== 'radio') return false;
    openPlayer(picked.id);
    return true;
  }
  // NOTE: no clearPick — the radio keeps playing while you pan the globe; the
  // player's × is the way to stop. That's the point of ambient world radio.

  return { id: 'radio', handlePick };
}