// PingQL Dashboard — shared utilities
// Auth is now cookie-based. No localStorage needed.

const API_BASE = window.location.origin;

function logout() {
  window.location.href = '/dashboard/logout';
}

// requireAuth is a no-op now — server redirects to /dashboard if not authed
function requireAuth() { return true; }

async function api(path, opts = {}) {
  const res = await fetch(`${API_BASE}${path}`, {
    ...opts,
    credentials: 'same-origin', // send cookie automatically
    headers: {
      'Content-Type': 'application/json',
      ...opts.headers,
    },
    body: opts.body ? JSON.stringify(opts.body) : undefined,
  });
  if (res.status === 401) {
    window.location.href = '/dashboard';
    throw new Error('Unauthorized');
  }
  const data = await res.json();
  if (!res.ok) throw new Error(data.error || 'API error');
  return data;
}

// Format relative time
function formatAgo(ms) {
  const s = Math.floor(ms / 1000);
  if (s < 60)   return `${s}s ago`;
  if (s < 3600) return `${Math.floor(s / 60)}m ago`;
  if (s < 86400)return `${Math.floor(s / 3600)}h ago`;
  return `${Math.floor(s / 86400)}d ago`;
}

function timeAgo(date) {
  const ts = new Date(date).getTime();
  const elapsed = Date.now() - ts;
  return `<span class="timestamp" data-ts="${ts}">${formatAgo(elapsed)}</span>`;
}

// Tick all live timestamps every second
setInterval(() => {
  document.querySelectorAll('.timestamp[data-ts]').forEach(el => {
    const elapsed = Date.now() - Number(el.dataset.ts);
    el.textContent = formatAgo(elapsed);
  });
}, 1000);

// Render a tiny sparkline SVG from latency values
function sparkline(values, width = 120, height = 32) {
  if (!values.length) return '';
  const max = Math.max(...values, 1);
  const min = Math.min(...values, 0);
  const range = max - min || 1;
  const step = width / Math.max(values.length - 1, 1);
  const points = values.map((v, i) => {
    const x = i * step;
    const y = height - ((v - min) / range) * (height - 4) - 2;
    return `${x},${y}`;
  }).join(' ');
  return `<svg width="${width}" height="${height}" class="inline-block"><polyline points="${points}" fill="none" stroke="#60a5fa" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"/></svg>`;
}

// Status badge
function statusBadge(up) {
  if (up === true) return '<span class="inline-block w-2.5 h-2.5 rounded-full bg-green-400 mr-2" title="Up"></span>';
  if (up === false) return '<span class="inline-block w-2.5 h-2.5 rounded-full bg-red-400 mr-2" title="Down"></span>';
  return '<span class="inline-block w-2.5 h-2.5 rounded-full bg-gray-600 mr-2" title="Unknown"></span>';
}

function escapeHtml(str) {
  const div = document.createElement('div');
  div.textContent = str;
  return div.innerHTML;
}

// Subscribe to live ping updates for a monitor via SSE (fetch-based for auth header support)
// Returns an AbortController — call .abort() to close
function watchMonitor(monitorId, onPing) {
  const ac = new AbortController();

  async function connect() {
    try {
      const res = await fetch(`/monitors/${monitorId}/stream`, {
        credentials: 'same-origin',
        signal: ac.signal,
      });
      if (!res.ok || !res.body) return;
      const reader = res.body.getReader();
      const dec = new TextDecoder();
      let buf = '';
      while (true) {
        const { done, value } = await reader.read();
        if (done) break;
        buf += dec.decode(value, { stream: true });
        const lines = buf.split('\n');
        buf = lines.pop() ?? '';
        for (const line of lines) {
          if (line.startsWith('data: ')) {
            try { onPing(JSON.parse(line.slice(6))); } catch {}
          }
        }
      }
    } catch (e) {
      if (e.name === 'AbortError') return;
      // Reconnect after a short delay on unexpected disconnect
      setTimeout(connect, 3000);
    }
  }

  connect();
  return ac;
}