import type { EmailVerificationToken } from '../../auth.types';

// Integration tests for TokenService against a live CouchDB instance.
// These tests require a local CouchDB at http://localhost:5984 with admin:password
// or credentials provided via environment variables.
//
// To run only these tests:
//   jest meds/services/auth/__tests__/integration/token.service.integration.test.ts
//
// Skips automatically if CouchDB is not reachable.

describe('TokenService (integration with CouchDB)', () => {
  const COUCH_URL =
    process.env.VITE_COUCHDB_URL ||
    process.env.COUCHDB_URL ||
    'http://localhost:5984';
  const COUCH_USER =
    process.env.VITE_COUCHDB_USER || process.env.COUCHDB_USER || 'admin';
  const COUCH_PASS =
    process.env.VITE_COUCHDB_PASSWORD ||
    process.env.COUCHDB_PASSWORD ||
    'password';

  const BASIC_AUTH =
    'Basic ' + Buffer.from(`${COUCH_USER}:${COUCH_PASS}`).toString('base64');

  let couchUp = false;
  let previousFetch: typeof fetch | undefined;
  let previousHeaders: typeof Headers | undefined;
  let previousRequest: typeof Request | undefined;
  let previousResponse: typeof Response | undefined;

  // TokenService and its dependencies will be imported after configuring env and fetch.
  let tokenService: any;

  // Utility: install a custom HTTP(S) fetch to reach real CouchDB (bypass test mocks)
  const installCustomFetch = async () => {
    previousFetch = global.fetch;
    previousHeaders = global.Headers as typeof Headers | undefined;
    previousRequest = global.Request as typeof Request | undefined;
    previousResponse = global.Response as typeof Response | undefined;

    // Use Node core undici (Node 18+)
    // Install a minimal HTTP(S)-based fetch to bypass test mocks
    const customFetch = async (url: string, init?: RequestInit) => {
      const { URL } = await import('node:url');
      const http = await import('node:http');
      const https = await import('node:https');
      const u = new URL(url);
      const isHttps = u.protocol === 'https:';
      const mod = isHttps ? https : http;
      const headers = init?.headers as Record<string, string> | undefined;
      const method = init?.method || 'GET';
      const body = init?.body as string | undefined;
      return await new Promise<Response>((resolve, reject) => {
        const req = mod.request(
          {
            protocol: u.protocol,
            hostname: u.hostname,
            port: u.port || (isHttps ? 443 : 80),
            path: u.pathname + (u.search || ''),
            method,
            headers,
          },
          res => {
            const chunks: Buffer[] = [];
            res.on('data', d =>
              chunks.push(Buffer.isBuffer(d) ? d : Buffer.from(d))
            );
            res.on('end', () => {
              const buf = Buffer.concat(chunks);
              const status = res.statusCode || 0;
              const headersMap = new Map<string, string>();
              for (const [k, v] of Object.entries(res.headers)) {
                if (Array.isArray(v)) headersMap.set(k, v.join(', '));
                else if (v != null) headersMap.set(k, String(v));
              }
              const responseLike = {
                ok: status >= 200 && status < 300,
                status,
                headers: {
                  get: (k: string) =>
                    headersMap.get(k.toLowerCase()) ||
                    headersMap.get(k) ||
                    null,
                  has: (k: string) =>
                    headersMap.has(k.toLowerCase()) || headersMap.has(k),
                },
                json: async () => {
                  const txt = buf.toString('utf8');
                  return txt ? JSON.parse(txt) : {};
                },
                text: async () => buf.toString('utf8'),
              } as unknown as Response;
              resolve(responseLike);
            });
          }
        );
        req.on('error', reject);
        if (body) req.write(body);
        req.end();
      });
    };
    // Override global fetch temporarily
    // @ts-ignore - test environment mutation
    global.fetch = customFetch as unknown as typeof fetch;
  };

  const restoreMockFetch = () => {
    if (previousFetch) global.fetch = previousFetch;
    if (previousHeaders) global.Headers = previousHeaders as typeof Headers;
    if (previousRequest) global.Request = previousRequest as typeof Request;
    if (previousResponse) global.Response = previousResponse as typeof Response;
  };

  const pingCouch = async (): Promise<boolean> => {
    try {
      const res = await fetch(`${COUCH_URL}/`, {
        headers: { Authorization: BASIC_AUTH },
      });
      return res.ok;
    } catch {
      return false;
    }
  };

  beforeAll(async () => {
    // Use development settings and disable mock DB so TokenService uses CouchDB
    process.env.NODE_ENV = 'development';
    process.env.USE_MOCK_DB = 'false';
    process.env.VITE_COUCHDB_URL = COUCH_URL;
    process.env.VITE_COUCHDB_USER = COUCH_USER;
    process.env.VITE_COUCHDB_PASSWORD = COUCH_PASS;

    await installCustomFetch();

    // Verify CouchDB is reachable
    couchUp = await pingCouch();
    if (!couchUp) {
      console.warn(
        `⚠️  CouchDB not reachable at ${COUCH_URL}. Skipping TokenService integration tests.`
      );
      restoreMockFetch();
      return;
    }

    // Ensure a clean module graph and import TokenService fresh with current env
    jest.resetModules();
    // import after env is set so unified config picks up these values
    const mod = await import('../../token.service');
    tokenService = mod.tokenService;

    // Trigger DB provisioning just in case
    // Save a no-op token then delete it; this ensures database exists.
    const bootstrapToken = `bootstrap-${Date.now()}`;
    await tokenService.savePasswordResetToken({
      userId: 'bootstrap',
      email: 'bootstrap@example.com',
      token: bootstrapToken,
      expiresAt: new Date(Date.now() + 60_000),
    });
    await tokenService.deletePasswordResetToken(bootstrapToken);
  }, 30000);

  afterAll(async () => {
    if (couchUp) {
      try {
        // Best-effort cleanup of expired tokens
        await tokenService.cleanupExpiredTokens();
      } catch {
        // ignore
      }
    }
    // Restore original mocked fetch for the rest of the test suite
    restoreMockFetch();
  });

  const itIf = (cond: boolean) => (cond ? it : it.skip);

  itIf(couchUp)(
    'saves and retrieves a verification token',
    async () => {
      const tokenValue = `ver-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const userId = `u-${Date.now()}`;
      const email = `user-${Date.now()}@example.com`;
      const expiresAt = new Date(Date.now() + 5 * 60_000);

      const token: EmailVerificationToken = {
        userId,
        email,
        token: tokenValue,
        expiresAt,
      };

      await tokenService.saveVerificationToken(token);

      const fetched = await tokenService.findVerificationToken(tokenValue);
      expect(fetched).toBeTruthy();
      expect(fetched.userId).toBe(userId);
      expect(fetched.email).toBe(email);
      expect(new Date(fetched.expiresAt).getTime()).toBe(expiresAt.getTime());

      // Cleanup
      await tokenService.deleteVerificationTokensForUser(userId);
      const after = await tokenService.findVerificationToken(tokenValue);
      expect(after).toBeNull();
    },
    30000
  );

  itIf(couchUp)(
    'deletes only verification tokens for the specified user',
    async () => {
      const tokenA = `verA-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const tokenB = `verB-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const userA = `userA-${Date.now()}`;
      const userB = `userB-${Date.now()}`;
      const exp = new Date(Date.now() + 10 * 60_000);

      await tokenService.saveVerificationToken({
        userId: userA,
        email: 'a@example.com',
        token: tokenA,
        expiresAt: exp,
      });
      await tokenService.saveVerificationToken({
        userId: userB,
        email: 'b@example.com',
        token: tokenB,
        expiresAt: exp,
      });

      // Delete tokens for userA
      await tokenService.deleteVerificationTokensForUser(userA);

      // Verify A is deleted
      const fa = await tokenService.findVerificationToken(tokenA);
      expect(fa).toBeNull();

      // Verify B still exists
      const fb = await tokenService.findVerificationToken(tokenB);
      expect(fb).toBeTruthy();
      expect(fb.userId).toBe(userB);

      // Cleanup B
      await tokenService.deleteVerificationTokensForUser(userB);
      const fbAfter = await tokenService.findVerificationToken(tokenB);
      expect(fbAfter).toBeNull();
    },
    30000
  );

  itIf(couchUp)(
    'password reset token lifecycle (save, find, delete)',
    async () => {
      const tokenValue = `rst-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const userId = `u-${Date.now()}`;
      const email = `reset-${Date.now()}@example.com`;
      const exp = new Date(Date.now() + 5 * 60_000);

      await tokenService.savePasswordResetToken({
        userId,
        email,
        token: tokenValue,
        expiresAt: exp,
      });

      const fetched = await tokenService.findPasswordResetToken(tokenValue);
      expect(fetched).toBeTruthy();
      expect(fetched.userId).toBe(userId);
      expect(fetched.email).toBe(email);

      await tokenService.deletePasswordResetToken(tokenValue);

      const after = await tokenService.findPasswordResetToken(tokenValue);
      expect(after).toBeNull();
    },
    30000
  );

  itIf(couchUp)(
    'cleanup removes expired tokens',
    async () => {
      const expiredToken = `expired-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const userId = `u-exp-${Date.now()}`;
      const email = `expired-${Date.now()}@example.com`;
      const past = new Date(Date.now() - 60_000);

      // Save one expired verification token
      await tokenService.saveVerificationToken({
        userId,
        email,
        token: expiredToken,
        expiresAt: past,
      });

      // And one valid token to ensure only expired is removed
      const validToken = `valid-${Date.now()}-${Math.random()
        .toString(16)
        .slice(2)}`;
      const future = new Date(Date.now() + 60_000);
      await tokenService.saveVerificationToken({
        userId,
        email,
        token: validToken,
        expiresAt: future,
      });

      const removed = await tokenService.cleanupExpiredTokens();
      expect(removed).toBeGreaterThanOrEqual(1);

      const expiredFetched =
        await tokenService.findVerificationToken(expiredToken);
      expect(expiredFetched).toBeNull();

      const validFetched = await tokenService.findVerificationToken(validToken);
      expect(validFetched).toBeTruthy();

      // Cleanup valid
      await tokenService.deleteVerificationTokensForUser(userId);
      const validAfter = await tokenService.findVerificationToken(validToken);
      expect(validAfter).toBeNull();
    },
    30000
  );
});