import { Router } from 'express';
import type { Cookie } from 'playwright';
import { z } from 'zod';
import type { WebContext } from '../context.js';

// Keep this server-side parser local: the server's tsconfig intentionally
// builds only src/, while the dashboard compiles the shared API contract.
const RedditCookieImportRequestSchema = z.strictObject({
  cookies: z.array(z.strictObject({
    name: z.string().min(1).max(256),
    value: z.string().max(16_384),
    domain: z.string().min(1).max(253),
    path: z.string().min(1).max(4_096).default('/'),
    expires: z.number().finite().optional(),
    httpOnly: z.boolean().optional(),
    secure: z.boolean().optional(),
    sameSite: z.enum(['strict', 'lax', 'none', 'no_restriction', 'unspecified']).optional(),
  })).min(1).max(100),
  matrix: z.strictObject({
    homeserver: z.string().url(),
    accessToken: z.string().min(1).max(16_384),
    userId: z.string().min(1).max(512),
    capturedAt: z.number().finite(),
  }),
});

function isRedditDomain(domain: string): boolean {
  const normalised = domain.toLowerCase().replace(/^\./, '');
  return normalised === 'reddit.com' || normalised.endsWith('.reddit.com');
}

function toPlaywrightCookie(cookie: { name: string; value: string; domain: string; path: string; expires?: number; httpOnly?: boolean; secure?: boolean; sameSite?: string }): Cookie {
  return {
    name: cookie.name,
    value: cookie.value,
    domain: cookie.domain,
    path: cookie.path,
    expires: cookie.expires ?? -1,
    httpOnly: cookie.httpOnly ?? false,
    secure: cookie.secure ?? true,
    sameSite: cookie.sameSite === 'strict' ? 'Strict' : cookie.sameSite === 'none' || cookie.sameSite === 'no_restriction' ? 'None' : 'Lax',
  };
}

export function createLoginRouter(ctx: WebContext): Router {
  const router = Router();

  router.get('/login/status', async (_req, res) => {
    const runningAccounts = ctx.services.redditAccounts?.list().filter((account) => account.isRunning) ?? [];
    if (runningAccounts.length > 0) {
      const only = runningAccounts.length === 1 ? runningAccounts[0] : null;
      res.json({
        ready: true,
        loggedIn: true,
        status: 'authenticated',
        accountId: only?.accountId ?? null,
        username: only?.redditUsername ?? null,
      });
      return;
    }
    const browser = ctx.services.browser;
    if (!browser) {
      res.status(503).json({ ready: false, error: 'browser not initialised' });
      return;
    }
    try {
      const accountAuth = ctx.services.accountAuth;
      const fullyAuthenticated = accountAuth
        ? await accountAuth.ensureFullyAuthenticated()
        : await browser.isSessionValid();
      if (fullyAuthenticated) {
        const snapshot = accountAuth?.getSnapshot();
        const username = snapshot?.redditUsername
          ?? await browser.getAuthenticatedUsername();
        res.json({
          ready: true,
          loggedIn: true,
          status: 'authenticated',
          ...(snapshot?.accountId ? { accountId: snapshot.accountId } : {}),
          username,
        });
        return;
      }

      await browser.isSessionValid();
      const browserState = browser.getSessionState();
      res.json({
        ready: true,
        loggedIn: false,
        status: browserState === 'unreachable' ? 'unreachable' : 'login-required',
        username: null,
      });
    } catch (error) {
      ctx.logger.error('Failed to check login status:', error);
      res.status(500).json({ ready: true, loggedIn: false, error: 'check failed' });
    }
  });

  router.post('/login/session-import', async (req, res) => {
    const importer = ctx.services.sessionImporter;
    if (!importer) {
      res.status(503).json({ ok: false, error: 'session importer not initialised' });
      return;
    }

    const payload = RedditCookieImportRequestSchema.safeParse(req.body);
    if (!payload.success) {
      res.status(400).json({ ok: false, error: 'Invalid Reddit session export' });
      return;
    }

    const cookies = payload.data.cookies.filter((cookie) => isRedditDomain(cookie.domain));
    if (cookies.length === 0) {
      res.status(400).json({ ok: false, error: 'The export did not contain Reddit cookies' });
      return;
    }

    try {
      const accounts = ctx.services.redditAccounts;
      if (!accounts) {
        await importer.import(cookies.map(toPlaywrightCookie), payload.data.matrix);
        ctx.logger.info(`Imported ${cookies.length} Reddit session cookies and verified the browser session`);
        res.json({ ok: true, status: 'authenticated' });
        return;
      }
      const account = await accounts.importSession(cookies.map(toPlaywrightCookie), payload.data.matrix);
      ctx.logger.info(`Imported ${cookies.length} Reddit session cookies and verified the browser session`);
      res.json({ ok: true, status: 'authenticated', account });
    } catch (error) {
      ctx.logger.error('Failed to import Reddit session cookies:', error);
      const message = error instanceof Error ? error.message : 'Could not import Reddit session';
      res.status(401).json({ ok: false, error: message });
    }
  });

  router.get('/accounts', (_req, res) => {
    const accounts = ctx.services.redditAccounts;
    if (!accounts) {
      res.status(503).json({ error: 'Reddit account service not initialised' });
      return;
    }
    res.json(accounts.list());
  });

  router.post('/accounts/:accountId/activate', async (req, res) => {
    const accounts = ctx.services.redditAccounts;
    if (!accounts) {
      res.status(503).json({ ok: false, error: 'Reddit account service not initialised' });
      return;
    }
    try {
      const account = await accounts.activate(decodeURIComponent(req.params.accountId));
      ctx.logger.info(`Activated Reddit account u/${account.redditUsername}`);
      res.json({ ok: true, account });
    } catch (error) {
      ctx.logger.error('Failed to activate Reddit account:', error);
      res.status(401).json({ ok: false, error: error instanceof Error ? error.message : 'Could not activate Reddit account' });
    }
  });

  router.delete('/accounts/:accountId', async (req, res) => {
    const accounts = ctx.services.redditAccounts;
    if (!accounts) {
      res.status(503).json({ ok: false, error: 'Reddit account service not initialised' });
      return;
    }
    const accountId = decodeURIComponent(req.params.accountId);
    try {
      const account = await accounts.remove(accountId);
      ctx.logger.info(`Removed Reddit account u/${account.redditUsername} and the content it owned`);
      res.json({ ok: true, account });
    } catch (error) {
      const message = error instanceof Error ? error.message : 'Could not remove Reddit account';
      if (message === 'Reddit account not found') {
        res.status(404).json({ ok: false, error: message });
        return;
      }
      ctx.logger.error('Failed to remove Reddit account:', error);
      res.status(500).json({ ok: false, error: message });
    }
  });

  return router;
}