/** Shared radio stats parsing/formatting (mirror of Android RadioSnapshot). */
(function (global) {
  'use strict';

  const KNOWN_LABELS = new Set([
    'send', 'receive', 'frequency', 'power', 'rssi', 'snr',
    'spreading factor', 'bandwidth', 'packet', 'packet number', 'payload',
    'on air', 'tx speed', 'rx speed', 'per', 'rx quality'
  ]);

  function roleLabel(role) {
    if (role === 'TX') return 'Передатчик (TX)';
    if (role === 'RX') return 'Приёмник (RX)';
    return role || '—';
  }

  function isKnownLabel(label) {
    const n = String(label || '').toLowerCase().trim();
    for (const k of KNOWN_LABELS) {
      if (n === k || n.includes(k)) return true;
    }
    return false;
  }

  function parseRadioSnapshot(meta, roleFallback, rssiFallback) {
    const snap = {
      role: roleFallback || null,
      frame: null,
      frequencyMhz: null,
      sf: null,
      bwKhz: null,
      powerDbm: null,
      rssiDbm: rssiFallback ?? null,
      snrDb: null,
      packet: null,
      payload: null,
      onAirMs: null,
      txPktPerS: null,
      rxPktPerS: null,
      perPercent: null,
      rxQualityPercent: null,
      extraFields: {}
    };
    if (!meta) return snap;
    let o = meta;
    if (typeof meta === 'string') {
      try { o = JSON.parse(meta); } catch (e) { return snap; }
    }
    if (o.role) snap.role = o.role;
    if (o.frame) snap.frame = o.frame;
    if (o.rssi_dbm != null) snap.rssiDbm = Number(o.rssi_dbm);
    if (o.power_dbm != null) snap.powerDbm = Number(o.power_dbm);
    if (o.snr_db != null) snap.snrDb = Number(o.snr_db);
    if (o.frequency_hz != null) snap.frequencyMhz = Number(o.frequency_hz) / 1e6;
    if (o.spreading_factor != null) snap.sf = Number(o.spreading_factor);
    if (o.bandwidth_khz != null) snap.bwKhz = Number(o.bandwidth_khz);
    if (o.packet != null) snap.packet = Number(o.packet);
    if (o.payload) snap.payload = String(o.payload);
    if (o.on_air_ms != null) snap.onAirMs = Number(o.on_air_ms);
    if (o.tx_pkt_per_s != null) snap.txPktPerS = Number(o.tx_pkt_per_s);
    if (o.rx_pkt_per_s != null) snap.rxPktPerS = Number(o.rx_pkt_per_s);
    if (o.per_percent != null) snap.perPercent = Number(o.per_percent);
    if (o.rx_quality_percent != null) snap.rxQualityPercent = Number(o.rx_quality_percent);
    if (o.fields && typeof o.fields === 'object') {
      for (const [k, v] of Object.entries(o.fields)) {
        if (!isKnownLabel(k)) snap.extraFields[k] = String(v);
        const nk = String(k).toLowerCase().trim();
        if (snap.rxQualityPercent == null && nk.includes('rx quality')) {
          const n = parseFloat(String(v).replace('%', '').trim());
          if (!Number.isNaN(n)) snap.rxQualityPercent = n;
        }
      }
    }
    return snap;
  }

  function diffSnapshots(a, b) {
    const changed = new Set();
    if (!a || !b) return changed;
    const keys = ['role', 'rssiDbm', 'snrDb', 'rxQualityPercent', 'packet', 'payload', 'perPercent',
      'txPktPerS', 'rxPktPerS', 'frequencyMhz', 'sf', 'bwKhz', 'powerDbm'];
    const map = { role: 'role', rssiDbm: 'rssi', snrDb: 'snr', rxQualityPercent: 'rxQuality',
      packet: 'packet',
      payload: 'payload', perPercent: 'per', txPktPerS: 'txSpeed', rxPktPerS: 'rxSpeed',
      frequencyMhz: 'frequency', sf: 'sf', bwKhz: 'bw', powerDbm: 'power' };
    for (const k of keys) {
      if (a[k] !== b[k] && !(a[k] == null && b[k] == null)) changed.add(map[k]);
    }
    return changed;
  }

  const DYNAMIC_ROWS = [
    { key: 'rssi', label: 'RSSI', fmt: s => s.rssiDbm != null ? `${s.rssiDbm} dBm` : '—' },
    { key: 'snr', label: 'SNR', fmt: s => s.snrDb != null ? `${s.snrDb} dB` : '—' },
    { key: 'rxQuality', label: 'RX Quality', fmt: s => s.rxQualityPercent != null ? `${s.rxQualityPercent} %` : '—' },
    { key: 'packet', label: 'Пакет', fmt: s => s.packet != null ? String(s.packet) : '—' },
    { key: 'payload', label: 'Payload', fmt: s => s.payload || '—' },
    { key: 'per', label: 'PER', fmt: s => s.perPercent != null ? `${s.perPercent} %` : '—' },
    { key: 'txSpeed', label: 'TX Speed', fmt: s => s.txPktPerS != null ? `${s.txPktPerS} pkt/s` : '—' },
    { key: 'rxSpeed', label: 'RX Speed', fmt: s => s.rxPktPerS != null ? `${s.rxPktPerS} pkt/s` : '—' }
  ];

  const STATIC_ROWS = [
    { key: 'role', label: 'Роль', fmt: s => roleLabel(s.role) },
    { key: 'frequency', label: 'Частота', fmt: s => s.frequencyMhz != null ? `${s.frequencyMhz.toFixed(3)} MHz` : '—' },
    { key: 'sf', label: 'SF', fmt: s => s.sf != null ? String(s.sf) : '—' },
    { key: 'bw', label: 'BW', fmt: s => s.bwKhz != null ? `${s.bwKhz} kHz` : '—' },
    { key: 'power', label: 'Мощность', fmt: s => s.powerDbm != null ? `${s.powerDbm} dBm` : '—' },
    { key: 'onAir', label: 'On Air', fmt: s => s.onAirMs != null ? `${s.onAirMs} ms` : '—' }
  ];

  function escapeHtml(s) {
    if (s == null) return '';
    return String(s).replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
  }

  function renderCompareGrid(txSnap, rxSnap, txId, rxId, changedTx, changedRx, staticOpen) {
    let html = '<div class="radio-compare-grid">';
    html += `<div class="radio-compare-head"><span class="legend-tx">TX</span> ${escapeHtml(txId || '—')}`;
    html += `<span class="legend-rx">RX</span> ${escapeHtml(rxId || '—')}</div>`;
    for (const row of DYNAMIC_ROWS) {
      const txCls = changedTx && changedTx.has(row.key) ? ' changed' : '';
      const rxCls = changedRx && changedRx.has(row.key) ? ' changed' : '';
      html += `<div class="radio-row"><span class="radio-label">${row.label}</span>`;
      html += `<span class="radio-tx${txCls}">${escapeHtml(row.fmt(txSnap))}</span>`;
      html += `<span class="radio-rx${rxCls}">${escapeHtml(row.fmt(rxSnap))}</span></div>`;
    }
    html += `<details class="radio-static"${staticOpen ? ' open' : ''}><summary>Статика</summary>`;
    for (const row of STATIC_ROWS) {
      const txCls = changedTx && changedTx.has(row.key) ? ' changed' : '';
      const rxCls = changedRx && changedRx.has(row.key) ? ' changed' : '';
      html += `<div class="radio-row"><span class="radio-label">${row.label}</span>`;
      html += `<span class="radio-tx${txCls}">${escapeHtml(row.fmt(txSnap))}</span>`;
      html += `<span class="radio-rx${rxCls}">${escapeHtml(row.fmt(rxSnap))}</span></div>`;
    }
    html += '</details></div>';
    return html;
  }

  function formatRadioPanel(snap, changed, staticOpen) {
    if (!snap) return '—';
    const ch = changed || new Set();
    let html = '';
    for (const row of DYNAMIC_ROWS) {
      const cls = ch.has(row.key) ? ' class="changed"' : '';
      html += `<div${cls}><b>${row.label}:</b> ${escapeHtml(row.fmt(snap))}</div>`;
    }
    for (const [label, value] of Object.entries(snap.extraFields || {})) {
      html += `<div><b>${escapeHtml(label)}:</b> ${escapeHtml(value)}</div>`;
    }
    html += `<details class="radio-static"${staticOpen ? ' open' : ''}><summary>Статика</summary>`;
    for (const row of STATIC_ROWS) {
      const cls = ch.has(row.key) ? ' class="changed"' : '';
      html += `<div${cls}><b>${row.label}:</b> ${escapeHtml(row.fmt(snap))}</div>`;
    }
    html += '</details>';
    return html;
  }

  global.RadioUI = {
    roleLabel,
    parseRadioSnapshot,
    diffSnapshots,
    renderCompareGrid,
    formatRadioPanel,
    DYNAMIC_ROWS,
    STATIC_ROWS
  };
})(typeof window !== 'undefined' ? window : globalThis);