import { el, mount, safeHref } from '../dom.js';
import { api } from '../api.js';

const SVG = 'http://www.w3.org/2000/svg';
const RANGES = [{ h: 24, l: '24h' }, { h: 168, l: '7d' }, { h: 720, l: '30d' }];
const INTERVALS = [
  { v: 15, l: 'Every 15 min' }, { v: 30, l: 'Every 30 min' }, { v: 60, l: 'Hourly' },
  { v: 120, l: 'Every 2 h' }, { v: 360, l: 'Every 6 h' }, { v: 720, l: 'Every 12 h' },
  { v: 1440, l: 'Daily' }
];

let hours = 168;
let timer = null;

const n1 = v => v == null ? '—' : Number(v).toFixed(1);
const n0 = v => v == null ? '—' : Math.round(Number(v));
function ago(ts) {
  if (!ts) return '—';
  const s = (Date.now() - new Date(ts).getTime()) / 1000;
  if (s < 90) return Math.round(s) + 's ago';
  if (s < 5400) return Math.round(s / 60) + 'm ago';
  if (s < 172800) return Math.round(s / 3600) + 'h ago';
  return Math.round(s / 86400) + 'd ago';
}

function mkSvg(tag, attrs) {
  const e = document.createElementNS(SVG, tag);
  for (const k in attrs) e.setAttribute(k, attrs[k]);
  return e;
}

// Multi-series line chart over a shared time axis. rows ascending by ran_at.
function chart(rows, series, h = 170) {
  if (!rows.length) return el('div', { class: 'muted', style: { padding: '24px 0' } }, 'No data in this window.');
  const W = 1000, H = h, padL = 42, padR = 10, padT = 10, padB = 18;
  const xs = rows.map(r => new Date(r.ran_at).getTime());
  const x0 = xs[0], x1 = xs[xs.length - 1] || x0 + 1;
  let vmax = 1;
  series.forEach(s => rows.forEach(r => { if (r[s.key] != null) vmax = Math.max(vmax, Number(r[s.key])); }));
  vmax *= 1.12;
  const X = t => padL + (x1 === x0 ? 0 : (t - x0) / (x1 - x0)) * (W - padL - padR);
  const Y = v => H - padB - (v / vmax) * (H - padT - padB);
  const svg = mkSvg('svg', { viewBox: `0 0 ${W} ${H}`, class: 'st-chart', preserveAspectRatio: 'none' });
  [0, 0.5, 1].forEach(f => {
    const y = Y(vmax * f);
    svg.appendChild(mkSvg('line', { x1: padL, x2: W - padR, y1: y, y2: y, stroke: '#ffffff10' }));
    const t = mkSvg('text', { x: 4, y: y + 3, fill: '#888094', 'font-size': 11 });
    t.textContent = Math.round(vmax * f); svg.appendChild(t);
  });
  series.forEach(s => {
    const pts = rows.filter(r => r[s.key] != null)
      .map(r => `${X(new Date(r.ran_at).getTime())},${Y(Number(r[s.key]))}`).join(' ');
    if (pts) svg.appendChild(mkSvg('polyline',
      { points: pts, fill: 'none', stroke: s.color, 'stroke-width': 2, 'stroke-linejoin': 'round' }));
  });
  return svg;
}

function legend(series) {
  return el('div', { class: 'st-legend' }, series.map(s =>
    el('span', { class: 'st-leg' }, el('i', { style: { background: s.color } }), s.label)));
}

function kpi(label, value, sub, cls) {
  return el('div', { class: 'st-kpi' + (cls ? ' ' + cls : '') },
    el('span', { class: 'st-kpi-l' }, label),
    el('span', { class: 'st-kpi-v' }, value),
    sub ? el('span', { class: 'st-kpi-s' }, sub) : null);
}

async function load(main) {
  let latest, statsd, rows, cfg;
  try {
    [latest, statsd, rows, cfg] = await Promise.all([
      api.get('/api/speedtest/latest'),
      api.get('/api/speedtest/stats?hours=' + hours),
      api.get('/api/speedtest/results?hours=' + hours),
      api.get('/api/speedtest/config')
    ]);
  } catch { mount(main, el('span', { class: 'muted' }, 'Speedtest data unavailable')); return; }

  const thr = Number(cfg.threshold_down_mbps) || 0;
  const lowNow = latest && thr > 0 && Number(latest.down_mbps) < thr;

  const rangeBtns = el('div', { class: 'st-ranges' }, RANGES.map(r =>
    el('button', { class: 'st-range' + (r.h === hours ? ' on' : ''), onclick: () => { hours = r.h; load(main); } }, r.l)));

  const runBtn = el('button', { class: 'primary' }, 'Run now');
  runBtn.onclick = async () => {
    runBtn.disabled = true; runBtn.textContent = 'Running…';
    try { await api.post('/api/speedtest/run', {}); } catch {}
    setTimeout(() => load(main), 35000);
  };

  // schedule + threshold form
  const intSel = el('select', { class: 'pm-input' }, INTERVALS.map(i =>
    el('option', { value: String(i.v) }, i.l)));
  intSel.value = String(cfg.interval_min);
  const thrIn = el('input', { class: 'pm-input', type: 'number', min: '0', step: '10', value: String(thr), style: { maxWidth: '110px' } });
  const saveBtn = el('button', {}, 'Save');
  const saveOut = el('span', { class: 'muted', style: { marginLeft: '8px' } });
  saveBtn.onclick = async () => {
    try {
      await api.put('/api/speedtest/config', {
        interval_min: Number(intSel.value), threshold_down_mbps: Number(thrIn.value) || 0
      });
      saveOut.textContent = 'Saved'; setTimeout(() => load(main), 500);
    } catch { saveOut.textContent = 'Failed'; }
  };

  mount(main,
    el('div', { class: 'st-head' },
      el('div', {},
        el('h1', { class: 'view-h1', style: { margin: 0 } }, 'Speedtest'),
        el('p', { class: 'view-sub', style: { margin: '2px 0 0' } },
          'Automated Ookla speed tests — history, trends & schedule.')),
      el('div', { class: 'st-actions' }, rangeBtns, runBtn)),

    // latest snapshot
    el('div', { class: 'st-kpis' },
      kpi('Download', latest ? n0(latest.down_mbps) : '—', 'Mbps', lowNow ? 'bad' : 'down'),
      kpi('Upload', latest ? n0(latest.up_mbps) : '—', 'Mbps', 'up'),
      kpi('Ping', latest ? n1(latest.ping_ms) : '—', 'ms'),
      kpi('Jitter', latest ? n1(latest.jitter_ms) : '—', 'ms'),
      kpi('Packet loss', latest ? n1(latest.packet_loss) : '—', '%'),
      kpi('Last run', ago(latest && latest.ran_at), latest && latest.isp ? latest.isp : '')),

    latest ? el('div', { class: 'st-meta muted' },
      latest.server_name ? `Server: ${latest.server_name}` : '',
      latest.result_url ? el('a', { href: safeHref(latest.result_url), target: '_blank', rel: 'noopener', class: 'st-link' }, ' view result ↗') : null,
      lowNow ? el('span', { class: 'st-warn' }, ` ⚠ below ${thr} Mbps threshold`) : null) : null,

    // stats for the window
    el('div', { class: 'st-stats' },
      el('span', {}, `Avg ↓ ${n0(statsd.avg_down)}`),
      el('span', {}, `min ${n0(statsd.min_down)} · max ${n0(statsd.max_down)}`),
      el('span', {}, `Avg ↑ ${n0(statsd.avg_up)}`),
      el('span', {}, `Avg ping ${n1(statsd.avg_ping)} ms`),
      el('span', {}, `${n0(statsd.n)} tests`),
      Number(statsd.failures) ? el('span', { class: 'st-warn' }, `${statsd.failures} failed`) : null),

    // charts
    el('h2', { class: 'st-h2' }, 'Throughput'),
    legend([{ color: 'var(--accent)', label: 'Download' }, { color: '#6fa86a', label: 'Upload' }]),
    chart(rows, [{ key: 'down_mbps', color: 'var(--accent)' }, { key: 'up_mbps', color: '#6fa86a' }], 180),
    el('h2', { class: 'st-h2' }, 'Latency'),
    legend([{ color: '#d4a04a', label: 'Ping (ms)' }, { color: '#7a7390', label: 'Jitter (ms)' }]),
    chart(rows, [{ key: 'ping_ms', color: '#d4a04a' }, { key: 'jitter_ms', color: '#7a7390' }], 130),

    // schedule
    el('div', { class: 'card st-card' },
      el('h3', {}, 'Schedule & alert'),
      el('div', { class: 'st-form' },
        el('label', { class: 'st-lbl' }, 'Run', intSel),
        el('label', { class: 'st-lbl' }, 'Alert if ↓ below (Mbps)', thrIn),
        saveBtn, saveOut)),

    // history table
    el('h2', { class: 'st-h2' }, 'History'),
    el('div', { class: 'st-table-wrap' },
      el('table', { class: 'st-table' },
        el('thead', {}, el('tr', {},
          ...['Time', 'Down', 'Up', 'Ping', 'Jitter', 'Loss', 'Server', ''].map(h => el('th', {}, h)))),
        el('tbody', {}, [...rows].reverse().slice(0, 100).map(r =>
          el('tr', { class: r.ok ? '' : 'st-fail' },
            el('td', {}, new Date(r.ran_at).toLocaleString('en-AU', { hour12: false, month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' })),
            el('td', { class: 'num' }, r.ok ? n0(r.down_mbps) : '✕'),
            el('td', { class: 'num' }, r.ok ? n0(r.up_mbps) : ''),
            el('td', { class: 'num' }, n1(r.ping_ms)),
            el('td', { class: 'num' }, n1(r.jitter_ms)),
            el('td', { class: 'num' }, r.packet_loss == null ? '—' : n1(r.packet_loss) + '%'),
            el('td', { class: 'muted' }, r.server_name || ''),
            el('td', {}, r.result_url ? el('a', { href: safeHref(r.result_url), target: '_blank', rel: 'noopener', class: 'st-link' }, '↗') : ''))))))
  );
}

export async function render(main) {
  hours = hours || 168;
  await load(main);
  if (timer) clearInterval(timer);
  timer = setInterval(() => {
    if (!document.querySelector('.st-kpis')) { clearInterval(timer); timer = null; return; }
    load(main);
  }, 30000);
}