import { INestApplication } from '@nestjs/common';
import { PrismaClient } from '@prisma/client';
import { unzipSync } from 'fflate';
import request from 'supertest';
import { afterAll, beforeAll, beforeEach, describe, expect, it } from 'vitest';

import { AuthTokensService } from '../auth/auth-tokens.service';
import { FilesService } from '../files/files.service';
import { createTestApp, sessionCookieOf } from '../testing/test-app';
import { createTestPrisma, grantOwnerAdmin, hasTestDb, uniqueSuffix } from '../testing/test-db';
import { UsersService } from '../users/users.service';

import { ConversionWorker } from './conversion-worker.service';
import { DataExportService } from './data-export.service';

/** GDPR data export (issue #68): a signed-in account assembles its own profile,
 * memberships, and the Markdown of every pond it owns into one ZIP — with a
 * download link that expires — and never another user's content. */

const PNG_BASE64 =
  'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAC0lEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==';

function zipEntries(buffer: Buffer): Record<string, Uint8Array> {
  return unzipSync(new Uint8Array(buffer));
}

function textOf(entries: Record<string, Uint8Array>, name: string): string {
  return Buffer.from(entries[name]!).toString('utf8');
}

async function downloadZip(server: unknown, path: string, cookie: string): Promise<Buffer> {
  const res = await request(server as never)
    .get(path)
    .set('Cookie', cookie)
    .buffer(true)
    .parse((r, cb) => {
      const chunks: Buffer[] = [];
      r.on('data', (c: Buffer) => chunks.push(c));
      r.on('end', () => cb(null, Buffer.concat(chunks)));
    })
    .expect(200);
  return res.body as Buffer;
}

describe.skipIf(!hasTestDb)('data export (e2e, issue #68)', () => {
  let app: INestApplication;
  let prisma: PrismaClient;
  let worker: ConversionWorker;
  let files: FilesService;
  const suffix = uniqueSuffix();
  const password = 'exportiere alle meine daten 1';

  let ownerId: string;
  let ownerCookie: string;
  let personalSlug: string;
  let ownedSharedSlug: string;
  let foreignSlug: string;

  const api = () => request(app.getHttpServer());

  async function login(username: string): Promise<string> {
    const res = await api()
      .post('/api/v1/auth/login')
      .send({ usernameOrEmail: username, password })
      .expect(200);
    return sessionCookieOf(res);
  }

  async function createUser(username: string): Promise<string> {
    const user = await app.get(UsersService).createUser({
      username,
      email: `${username}@example.org`,
      displayName: username,
      password,
      locale: 'en',
    });
    // Verify via the endpoint (not a direct flag flip) so the personal pond and
    // its owner-admin grant are created exactly as in production (#52).
    const token = await app.get(AuthTokensService).issue(user.id, 'EMAIL_VERIFICATION', 600);
    await api().post('/api/v1/auth/verify-email').send({ token }).expect(204);
    return user.id;
  }

  async function seedPage(pondId: string, title: string, markdown: string): Promise<void> {
    await prisma.page.create({
      data: {
        pondId,
        title,
        slug: title.toLowerCase().replace(/[^a-z0-9]+/g, '-'),
        ydocState: new Uint8Array(),
        sortKey: title,
        createdBy: ownerId,
        contentCache: { create: { plainText: markdown, markdown, html: '', outline: [] } },
      },
    });
  }

  beforeAll(async () => {
    prisma = createTestPrisma();
    await prisma.rateLimit.deleteMany({});
    app = await createTestApp();
    worker = app.get(ConversionWorker);
    files = app.get(FilesService);

    ownerId = await createUser(`odette-owner-${suffix}`);
    ownerCookie = await login(`odette-owner-${suffix}`);

    const personal = await prisma.pond.findFirstOrThrow({
      where: { ownerId, type: 'PERSONAL' },
    });
    personalSlug = personal.slug;

    // A shared pond the owner created — its content belongs in the export.
    const shared = await prisma.pond.create({
      data: {
        slug: `owned-shared-${suffix}`,
        name: 'Owned Shared',
        type: 'SHARED',
        ownerId,
        usage: { create: {} },
      },
    });
    ownedSharedSlug = shared.slug;
    await grantOwnerAdmin(prisma, shared.id, ownerId);

    // A stored image referenced from a personal-pond page (media inclusion).
    const image = await files.upload({ id: ownerId } as never, personal.id, {
      buffer: Buffer.from(PNG_BASE64, 'base64'),
      size: 70,
      originalname: 'dot.png',
    });
    await seedPage(personal.id, 'Diary', `# Diary\n\nMine. ![dot](${image.id})`);
    await seedPage(shared.id, 'Shared Note', '# Shared Note\n\nAlso mine.');

    // A foreign user's pond the owner is only a *reader* of: it must show up in
    // memberships, but its content must never appear in the export.
    const foreignId = await createUser(`fred-foreign-${suffix}`);
    const foreign = await prisma.pond.create({
      data: {
        slug: `foreign-secret-${suffix}`,
        name: 'Foreign Secret',
        type: 'SHARED',
        ownerId: foreignId,
        usage: { create: {} },
      },
    });
    foreignSlug = foreign.slug;
    await prisma.page.create({
      data: {
        pondId: foreign.id,
        title: 'Foreign Page',
        slug: 'foreign-page',
        ydocState: new Uint8Array(),
        sortKey: 'Foreign Page',
        createdBy: foreignId,
        contentCache: {
          create: { plainText: 'TOP SECRET', markdown: 'TOP SECRET', html: '', outline: [] },
        },
      },
    });
    await prisma.roleGrant.create({
      data: {
        pondId: foreign.id,
        subjectType: 'USER',
        subjectId: ownerId,
        role: 'READER',
        scopeType: 'POND',
        effect: 'ALLOW',
        createdBy: foreignId,
      },
    });
  });

  afterAll(async () => {
    await prisma.conversionJob.deleteMany({ where: { owner: { username: { contains: suffix } } } });
    const where = { pond: { owner: { username: { contains: suffix } } } };
    await prisma.attachment.deleteMany({ where });
    await prisma.roleGrant.deleteMany({
      where: { pond: { owner: { username: { contains: suffix } } } },
    });
    await prisma.page.deleteMany({ where });
    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
    await prisma.rateLimit.deleteMany({});
    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
    await prisma.$disconnect();
    await app.close();
  });

  // Each test starts from a clean rate-limit table so the per-account export
  // limit (exercised deliberately in one test) never trips the others.
  beforeEach(async () => {
    await prisma.rateLimit.deleteMany({});
  });

  it('exports the caller profile, memberships, and owned pond content only', async () => {
    const enqueued = await api()
      .post('/api/v1/users/me/data-export')
      .set('Cookie', ownerCookie)
      .expect(201);
    expect(enqueued.body.kind).toBe('data_export');
    expect(enqueued.body.status).toBe('pending');

    await worker.drain();

    const done = await api()
      .get(`/api/v1/jobs/${enqueued.body.id}`)
      .set('Cookie', ownerCookie)
      .expect(200);
    expect(done.body.status).toBe('succeeded');
    // The download link carries an expiry (a future timestamp).
    expect(done.body.expiresAt).toBeTruthy();
    expect(new Date(done.body.expiresAt).getTime()).toBeGreaterThan(Date.now());

    const zip = await downloadZip(
      app.getHttpServer(),
      `/api/v1/jobs/${enqueued.body.id}/result`,
      ownerCookie,
    );
    const entries = zipEntries(zip);
    const names = Object.keys(entries);

    // Profile: the caller's own account fields.
    const profile = JSON.parse(textOf(entries, 'profile.json'));
    expect(profile.username).toBe(`odette-owner-${suffix}`);
    expect(profile.email).toBe(`odette-owner-${suffix}@example.org`);

    // Personal + owned-shared pond content is present, media included.
    expect(names).toContain(`ponds/${personalSlug}/diary.md`);
    expect(names.some((n) => n.startsWith(`ponds/${personalSlug}/media/`))).toBe(true);
    expect(names).toContain(`ponds/${ownedSharedSlug}/shared-note.md`);

    // Memberships list the foreign pond the owner reads…
    const memberships = JSON.parse(textOf(entries, 'memberships.json')) as {
      pondSlug: string;
    }[];
    expect(memberships.map((m) => m.pondSlug)).toContain(foreignSlug);

    // …but none of the foreign pond's content appears anywhere in the archive.
    expect(names.some((n) => n.startsWith(`ponds/${foreignSlug}/`))).toBe(false);
    for (const name of names) {
      if (name.endsWith('.md')) expect(textOf(entries, name)).not.toContain('TOP SECRET');
    }
  });

  it('404s the download once the link has expired', async () => {
    const enqueued = await api()
      .post('/api/v1/users/me/data-export')
      .set('Cookie', ownerCookie)
      .expect(201);
    await worker.drain();
    // Backdate the expiry to simulate an elapsed link.
    await prisma.conversionJob.update({
      where: { id: enqueued.body.id },
      data: { expiresAt: new Date(Date.now() - 1000) },
    });

    await api()
      .get(`/api/v1/jobs/${enqueued.body.id}/result`)
      .set('Cookie', ownerCookie)
      .expect(404);
  });

  it('purges the stored bytes of an expired export', async () => {
    const enqueued = await api()
      .post('/api/v1/users/me/data-export')
      .set('Cookie', ownerCookie)
      .expect(201);
    await worker.drain();
    await prisma.conversionJob.update({
      where: { id: enqueued.body.id },
      data: { expiresAt: new Date(Date.now() - 1000) },
    });

    const purged = await app.get(DataExportService).purgeExpired();
    expect(purged).toBeGreaterThanOrEqual(1);
    const row = await prisma.conversionJob.findUniqueOrThrow({ where: { id: enqueued.body.id } });
    expect(row.result).toBeNull();
  });

  it('rate-limits repeated requests from the same account', async () => {
    await createUser(`irene-idle-${suffix}`);
    const cookie = await login(`irene-idle-${suffix}`);
    // The limit is a few requests per window; the run past it is rejected.
    for (let i = 0; i < 3; i += 1) {
      await api().post('/api/v1/users/me/data-export').set('Cookie', cookie).expect(201);
    }
    await api().post('/api/v1/users/me/data-export').set('Cookie', cookie).expect(429);
  });

  it('keeps a data-export job owner-scoped (a foreign user cannot poll it)', async () => {
    const enqueued = await api()
      .post('/api/v1/users/me/data-export')
      .set('Cookie', ownerCookie)
      .expect(201);
    await createUser(`sam-stranger-${suffix}`);
    const strangerCookie = await login(`sam-stranger-${suffix}`);
    await api().get(`/api/v1/jobs/${enqueued.body.id}`).set('Cookie', strangerCookie).expect(404);
  });
});