// Shared page runtime: site config, nav, formatting. Zero dependencies.
window.IAP = (function () {
  let config = null;
  const $ = id => document.getElementById(id);

  async function getConfig() {
    if (!config) config = await (await fetch('/api/config')).json();
    return config;
  }
  function fmtPol(wei) {
    const s = BigInt(wei).toString().padStart(19, '0');
    const whole = s.slice(0, -18) || '0';
    const frac = s.slice(-18, -12).replace(/0+$/, '');
    return whole + (frac ? '.' + frac : '');
  }
  const fmtUsd = cents => '$' + (cents / 100).toFixed(2);

  function status(msg, cls) {
    let el = $('status');
    if (!el) { el = document.createElement('div'); el.id = 'status'; document.body.appendChild(el); }
    el.textContent = msg; el.className = cls || ''; el.hidden = false;
    clearTimeout(status._t);
    if (cls === 'ok') status._t = setTimeout(() => { el.hidden = true; }, 6000);
  }

  async function renderNav(active) {
    const c = await getConfig();
    const nav = document.createElement('nav');
    nav.innerHTML = '<div class="wrap">'
      + '<a class="logo" href="/">Instant<b>AdPay</b></a>'
      + '<span class="links">'
      + '<a href="/" data-p="home">How it works</a>'
      + '<a href="/#ladder" data-p="pricing">Ad packages</a>'
      + '<a href="/ledger" data-p="ledger">Live ledger</a>'
      + '<a href="/contract" data-p="contract">The contract</a>'
      + '<a href="/my" data-p="my">Members</a>'
      + '</span><span id="navWallet" class="muted">…</span></div>';
    document.body.prepend(nav);
    if (c.rehearsal) {
      const b = document.createElement('div');
      b.className = 'rehearsal';
      b.innerHTML = '<b>Testnet rehearsal</b>: running on ' + c.chainName + '. Purchases use valueless test POL while we prove every payout in public.';
      document.body.prepend(b);
    }
    const a = nav.querySelector('[data-p="' + active + '"]');
    if (a) a.className = 'active';
    refreshNavWallet();
  }
  async function refreshNavWallet() {
    try {
      const me = await (await fetch('/api/me')).json();
      const el = $('navWallet');
      if (!el) return;
      if (me.signedIn) {
        // identity order: username, then email, then wallet
        const who = me.username
          ? '<b>@' + String(me.username).replace(/[&<>]/g, '') + '</b>'
          : (me.email ? String(me.email).replace(/[&<>]/g, '')
            : (me.address ? '<span class="mono">' + me.address.slice(0, 6) + '…' + me.address.slice(-4) + '</span>' : 'signed in'));
        el.innerHTML = (me.memberId ? '<span class="badge">member #' + me.memberId + '</span> ' : '') + who;
      } else {
        el.innerHTML = '<a href="/my">Sign in</a>';
      }
      return me;
    } catch (e) { return null; }
  }
  function describeEvent(ev, c) {
    const pol = w => fmtPol(w) + ' POL';
    // real people, not numbers: use usernames when the site knows them
    const nm = id => (ev.names && ev.names[id])
      ? String(ev.names[id]).replace(/[&<>]/g, '')
      : 'member #' + id;
    switch (ev.type) {
      case 'Purchase': return '🧾 ' + nm(ev.buyerId) + ' bought package #' + ev.productId
        + ' (' + fmtUsd(ev.priceCents) + ') for ' + pol(ev.paidWei) + ' → +' + ev.creditAmount.toLocaleString() + ' credits';
      case 'TierPaid': return '💸 level ' + ev.tier + ' payout → ' + nm(ev.recipientId) + ': ' + pol(ev.amountWei)
        + (ev.hops ? ' (passed up ' + ev.hops + ')' : '');
      case 'PassedUp': return '↷ level ' + ev.tier + ' passed over ' + nm(ev.skippedId) + ' (' + ev.reason + ')';
      case 'AdminPaid': return '🏛 platform fee settled: ' + pol(ev.amountWei);
      case 'BuyerCounted': return '⭐ ' + nm(ev.sponsorId) + ' now has ' + ev.newCount + ' qualifying buyer(s)';
      case 'MemberActivated': return '👤 ' + nm(ev.id) + ' activated a payout wallet';
      case 'AwardPaid': return '🎁 award: ' + pol(ev.amountWei) + ' → ' + nm(ev.toId);
      case 'CreditsConsumed': return '📣 ' + nm(ev.memberId) + ' ran ads: −' + ev.amount.toLocaleString() + ' credits';
      case 'PriceCached': return '🔮 oracle price refreshed';
      case 'FallbackPriceUsed': return '🔮 cached price bridged an oracle gap';
      default: return '· ' + ev.type;
    }
  }
  function feedRow(ev, c) {
    const div = document.createElement('div');
    div.className = 'row t-' + ev.type;
    div.innerHTML = '<span>' + describeEvent(ev, c) + '</span>'
      + (c.explorer
        ? '<span class="tx"><a target="_blank" rel="noopener" href="' + c.explorer + '/tx/' + ev.tx + '">verify ↗</a></span>'
        : '<span class="tx"><a href="/tx/' + ev.tx + '">verify ↗</a></span>'); // built-in viewer when the chain has no public explorer
    return div;
  }
  // Render one served ad into #<elId>. Silent if no inventory.
  async function adSlot(type, elId) {
    try {
      const { ad } = await (await fetch('/api/ads/slot?type=' + type)).json();
      const el = $(elId);
      if (!ad || !el) return;
      if (ad.imageUrl) {
        el.innerHTML = '<a href="' + ad.targetUrl + '" target="_blank" rel="noopener nofollow">'
          + '<img src="' + ad.imageUrl + '" alt="advertisement" style="max-width:100%;border-radius:8px"></a>'
          + '<div class="small muted">member ad</div>';
      } else {
        el.innerHTML = '<a href="' + ad.targetUrl + '" target="_blank" rel="noopener nofollow"><b>' + ad.title + '</b>'
          + (ad.body ? ' · ' + ad.body : '') + '</a> <span class="small muted">member ad</span>';
      }
      el.hidden = false;
    } catch (e) {}
  }
  return { getConfig, fmtPol, fmtUsd, status, renderNav, refreshNavWallet, describeEvent, feedRow, adSlot, $ };
})();