/// Device management view — list devices with revoke actions.

import { setState, sendMessage, navigate, escapeHtml } from '../../shared/state';
import type { Device } from '../../shared/types';
import { relativeTime } from '../../shared/relative-time';
import { sshFingerprint } from '../../shared/ssh-fingerprint';
import { GLYPH_REVOKE } from '../../shared/glyphs';

interface RevokedEntry {
  name: string;
  public_key: string;
  revoked_at: number;
  revoked_by: string;
}

function detectDefaultDeviceName(): string {
  const ua = navigator.userAgent ?? '';
  const platform = (navigator.platform ?? '').toLowerCase();
  const isFirefox = /firefox/i.test(ua);
  const isEdge = /edg/i.test(ua);
  const isChrome = /chrome/i.test(ua) && !isEdge;
  const browser = isFirefox ? 'Firefox' : isEdge ? 'Edge' : isChrome ? 'Chrome' : 'Browser';
  const os = platform.includes('mac') ? 'macOS'
    : platform.includes('win') ? 'Windows'
    : platform.includes('linux') ? 'Linux'
    : 'Unknown';
  return `${browser} on ${os}`;
}

export function teardown(): void {
  // No cleanup needed
}

/**
 * DEV-C P2: defensive per-slot rendering. The active list is the primary
 * feed — if it fails entirely, we still surface an error page. The
 * revoked list is secondary — its failure renders an inline "couldn't
 * load" slot but doesn't kill the page.
 */
function revokedLoadErrorHtml(): string {
  return `
    <details class="revoked-section">
      <summary class="muted">▸ revoked devices</summary>
      <div class="revoked-section__body">
        <p class="muted">Couldn't load revoked devices.</p>
      </div>
    </details>
  `;
}

export async function renderDevices(app: HTMLElement): Promise<void> {
  // Get current device name from local storage
  const stored = await chrome.storage.local.get(['device_name']);
  const currentDeviceName: string | undefined = stored.device_name as string | undefined;

  // Fetch active device list and revoked list in parallel. allSettled so a
  // rejected secondary feed doesn't kill the whole render.
  const [devicesSettled, revokedSettled] = await Promise.allSettled([
    sendMessage({ type: 'list_devices' }),
    sendMessage({ type: 'list_revoked' }),
  ]);

  if (devicesSettled.status === 'rejected' || !devicesSettled.value.ok) {
    app.innerHTML = `<div class="pad"><p class="error">Failed to load devices</p></div>`;
    return;
  }

  // devicesSettled.value.ok is true here (guarded above), so .data is present.
  const devicesData = (devicesSettled.value as { ok: true; data: unknown }).data;
  const devices = (devicesData as { devices: Device[] }).devices;
  const revokedOk = revokedSettled.status === 'fulfilled' && revokedSettled.value.ok;
  const revokedDevices: RevokedEntry[] = revokedOk
    ? ((revokedSettled.value as { ok: true; data: unknown }).data as { revoked: RevokedEntry[] }).revoked
    : [];

  const isRegistered = currentDeviceName && devices.some((d) => d.name === currentDeviceName);

  // Precompute fingerprints for all active devices. allSettled so one bad
  // public key doesn't kill the whole list — fall back to '(unknown)'.
  const fingerprints = new Map<string, string>();
  const fpResults = await Promise.allSettled(
    devices.map((d) => sshFingerprint(d.public_key).then((fp) => [d.name, fp] as const)),
  );
  for (let i = 0; i < devices.length; i += 1) {
    const r = fpResults[i];
    if (r.status === 'fulfilled' && r.value[1]) {
      fingerprints.set(r.value[0], r.value[1]);
    } else {
      fingerprints.set(devices[i].name, '(unknown)');
    }
  }

  const activeDevicesHtml = devices.length === 0
    ? `<p class="muted" style="text-align:center;margin-top:32px;">No devices registered</p>`
    : devices.map((d) => {
        const isCurrentDevice = d.name === currentDeviceName;
        const fp = fingerprints.get(d.name) ?? '(unknown)';
        const addedBy = d.added_by && d.added_by !== 'unknown' ? ` · by ${escapeHtml(d.added_by)}` : '';
        return `
          <div class="device-row" data-device="${escapeHtml(d.name)}">
            <div class="device-row__head">
              <span class="device-row__name">${escapeHtml(d.name)}</span>
              ${isCurrentDevice
                ? '<span class="device-row__you">← you</span>'
                : `<button class="glyph-btn" data-danger data-revoke="${escapeHtml(d.name)}" title="revoke" aria-label="revoke ${escapeHtml(d.name)}">${GLYPH_REVOKE}</button>`}
            </div>
            <div class="fingerprint">${escapeHtml(fp)}</div>
            <div class="device-row__meta">added ${escapeHtml(relativeTime(d.added_at))}${addedBy}</div>
            <div class="device-row__confirm" data-confirm-for="${escapeHtml(d.name)}" hidden></div>
          </div>
        `;
      }).join('');

  const revokedSectionHtml = !revokedOk
    ? revokedLoadErrorHtml()
    : revokedDevices.length === 0 ? '' : `
    <details class="revoked-section">
      <summary class="muted">▸ show ${revokedDevices.length} revoked device${revokedDevices.length !== 1 ? 's' : ''}</summary>
      <div class="revoked-section__body">
        ${revokedDevices.map((r) => `
          <div class="device-row device-row--revoked">
            <div class="device-row__head">
              <span class="device-row__name" style="text-decoration:line-through;opacity:0.6;">
                ${escapeHtml(r.name)}
              </span>
            </div>
            <div class="device-row__meta">
              revoked ${escapeHtml(relativeTime(r.revoked_at))}${r.revoked_by !== 'unknown' ? ` · by ${escapeHtml(r.revoked_by)}` : ''}
            </div>
          </div>
        `).join('')}
      </div>
    </details>
  `;

  app.innerHTML = `
    <div class="pad">
      <div class="devices-header">
        <button class="btn" id="back-btn">← back</button>
        <h3 style="margin:0;">devices</h3>
      </div>
      ${!isRegistered ? `
        <div class="device-banner">
          <div class="device-banner__title">This device isn't registered.</div>
          <p class="device-banner__body muted">Registering generates an ed25519 keypair and adds the public key to <code>.relicario/devices.json</code> on the remote.</p>
          <button class="btn btn-primary" id="register-btn">Register this device</button>
        </div>
      ` : ''}
      ${devices.length > 0 ? `<div class="section-header">ACTIVE · ${devices.length}</div>` : ''}
      ${activeDevicesHtml}
      ${!revokedOk ? `<div class="section-header">REVOKED · ?</div>` : (revokedDevices.length > 0 ? `<div class="section-header">REVOKED · ${revokedDevices.length}</div>` : '')}
      ${revokedSectionHtml}
    </div>
  `;

  // Wire handlers
  document.getElementById('back-btn')?.addEventListener('click', () => navigate('list'));

  document.getElementById('register-btn')?.addEventListener('click', () => {
    const banner = document.querySelector('.device-banner');
    if (!banner) return;
    const defaultName = detectDefaultDeviceName();
    banner.innerHTML = `
      <label class="label" for="register-name-input" style="display:block;margin-bottom:4px;">
        Name this device
      </label>
      <input
        id="register-name-input"
        type="text"
        value="${escapeHtml(defaultName)}"
        style="width:100%;margin-bottom:8px;"
      >
      <div style="display:flex;gap:8px;">
        <button class="btn btn-primary" id="register-confirm-btn">Register</button>
        <button class="btn" id="register-cancel-btn">Cancel</button>
      </div>
    `;

    document.getElementById('register-cancel-btn')?.addEventListener('click', () => {
      renderDevices(app);
    });

    document.getElementById('register-confirm-btn')?.addEventListener('click', async () => {
      const input = document.getElementById('register-name-input') as HTMLInputElement | null;
      const name = input?.value.trim();
      if (!name) {
        setState({ error: 'Device name is required' });
        return;
      }
      const result = await sendMessage({ type: 'register_this_device', name });
      if (result.ok) {
        renderDevices(app);
      } else {
        setState({ error: result.error });
      }
    });
  });

  document.querySelectorAll<HTMLButtonElement>('[data-revoke]').forEach((btn) => {
    btn.addEventListener('click', () => {
      const name = btn.dataset.revoke;
      if (!name) return;
      const panel = document.querySelector<HTMLElement>(`[data-confirm-for="${CSS.escape(name)}"]`);
      if (!panel) return;
      panel.hidden = false;
      panel.innerHTML = `
        <p class="device-row__confirm-text">
          Revoke this device? It won't be able to sign commits or push changes after revocation.
        </p>
        <div class="device-row__confirm-actions">
          <button class="btn" data-revoke-cancel="${escapeHtml(name)}">cancel</button>
          <button class="btn btn-danger" data-revoke-confirm="${escapeHtml(name)}">revoke</button>
        </div>
      `;
      btn.disabled = true;

      panel.querySelector('[data-revoke-cancel]')?.addEventListener('click', () => {
        panel.hidden = true;
        panel.innerHTML = '';
        btn.disabled = false;
      });

      panel.querySelector('[data-revoke-confirm]')?.addEventListener('click', async () => {
        const confirmBtn = panel.querySelector<HTMLButtonElement>('[data-revoke-confirm]')!;
        confirmBtn.disabled = true;
        confirmBtn.textContent = '...';
        const result = await sendMessage({ type: 'revoke_device', name });
        if (result.ok) {
          await sendMessage({ type: 'sync' });
          renderDevices(app);
        } else {
          setState({ error: result.error });
          confirmBtn.disabled = false;
          confirmBtn.textContent = 'revoke';
        }
      });
    });
  });
}