import { existsSync } from 'node:fs';
import { join } from 'node:path';

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

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

const PNG_SIGNATURE = Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
const pngBuffer = (payload = 'fake-but-signed png bytes'): Buffer =>
  Buffer.concat([PNG_SIGNATURE, Buffer.from(payload)]);

/** superagent has no default parser for image/*; buffer the raw bytes ourselves. */
function binaryParser(
  res: NodeJS.ReadableStream,
  callback: (err: Error | null, body: Buffer) => void,
): void {
  const chunks: Buffer[] = [];
  res.on('data', (chunk: Buffer) => chunks.push(chunk));
  res.on('end', () => callback(null, Buffer.concat(chunks)));
}
type ParseCallback = Parameters<Test['parse']>[0];

describe.skipIf(!hasTestDb)('files (e2e, issue #27)', () => {
  let app: INestApplication;
  let prisma: PrismaClient;
  const suffix = uniqueSuffix();
  const password = 'bilder hochladen ist toll 1';

  const owner = { username: `fiona-files-${suffix}`, displayName: `Fiona Files ${suffix}` };
  const outsider = { username: `otto-files-${suffix}`, displayName: `Otto Outside ${suffix}` };
  let ownerCookie: string;
  let outsiderCookie: string;
  let pondId: string;

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

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

  async function setPondOverride(quotaKey: string, value: number): Promise<void> {
    await prisma.quotaOverride.upsert({
      where: {
        subjectType_subjectId_quotaKey: { subjectType: 'POND', subjectId: pondId, quotaKey },
      },
      create: { subjectType: 'POND', subjectId: pondId, quotaKey, value },
      update: { value },
    });
  }

  async function clearPondOverrides(): Promise<void> {
    await prisma.quotaOverride.deleteMany({ where: { subjectType: 'POND', subjectId: pondId } });
  }

  beforeAll(async () => {
    prisma = createTestPrisma();
    await prisma.rateLimit.deleteMany({});
    app = await createTestApp();
    const users = app.get(UsersService);
    const tokens = app.get(AuthTokensService);

    const ownerUser = await users.createUser({
      username: owner.username,
      email: `${owner.username}@example.org`,
      displayName: owner.displayName,
      password,
      locale: 'en',
    });
    const verifyToken = await tokens.issue(ownerUser.id, 'EMAIL_VERIFICATION', 600);
    await api().post('/api/v1/auth/verify-email').send({ token: verifyToken }).expect(204);
    ownerCookie = await loginOf(owner.username);

    const outsiderUser = await users.createUser({
      username: outsider.username,
      email: `${outsider.username}@example.org`,
      displayName: outsider.displayName,
      password,
      locale: 'en',
    });
    await users.markEmailVerified(outsiderUser.id);
    outsiderCookie = await loginOf(outsider.username);

    const ponds = await api().get('/api/v1/ponds').set('Cookie', ownerCookie).expect(200);
    pondId = ponds.body.find((p: { type: string }) => p.type === 'personal').id;
  });

  afterAll(async () => {
    await prisma.attachment.deleteMany({ where: { pondId } });
    await prisma.page.deleteMany({
      where: { pond: { owner: { username: { contains: suffix } } } },
    });
    const users = await prisma.user.findMany({
      where: { username: { contains: suffix } },
      select: { id: true },
    });
    await prisma.quotaOverride.deleteMany({
      where: { subjectId: { in: [pondId, ...users.map((u) => u.id)] } },
    });
    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
    await prisma.$disconnect();
    await app.close();
  });

  it('roundtrips an uploaded image: same bytes, sniffed content type', async () => {
    const bytes = pngBuffer('roundtrip');
    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', bytes, 'photo.png')
      .expect(201);
    expect(uploaded.body.mimeType).toBe('image/png');
    expect(uploaded.body.sizeBytes).toBe(bytes.length);

    const served = await api()
      .get(`/api/v1/media/${uploaded.body.id}`)
      .set('Cookie', ownerCookie)
      .buffer(true)
      .parse(binaryParser as unknown as ParseCallback)
      .expect(200);
    expect(served.headers['content-type']).toBe('image/png');
    expect(served.headers['x-content-type-options']).toBe('nosniff');
    expect(Buffer.compare(served.body, bytes)).toBe(0);
  });

  it('accepts an allowlisted non-image file and serves it as a download (#61)', async () => {
    const pdf = Buffer.from('%PDF-1.4 minimal but allowlisted');
    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', pdf, 'document.pdf')
      .expect(201);
    expect(uploaded.body.mimeType).toBe('application/pdf');

    const served = await api()
      .get(`/api/v1/media/${uploaded.body.id}`)
      .set('Cookie', ownerCookie)
      .buffer(true)
      .parse(binaryParser as unknown as ParseCallback)
      .expect(200);
    // Non-images are always downloads, never inline (ADR 0011, security.md).
    expect(served.headers['content-disposition']).toContain('attachment');
    expect(served.headers['content-disposition']).toContain('document.pdf');
    expect(served.headers['content-type']).toContain('application/pdf');
  });

  it('rejects a file whose extension is not on the allowlist (#61)', async () => {
    const res = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', Buffer.from('binary junk'), 'malware.exe')
      .expect(400);
    expect(res.body.code).toBe('upload_type_not_allowed');
    expect(res.body.details.allowed).toContain('pdf');
  });

  it('rejects a renamed .html-as-.png via the magic-byte check (#61)', async () => {
    const res = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', Buffer.from('<html><body>evil</body></html>'), 'sneaky.png')
      .expect(400);
    // png is validated by bytes, not extension, so the disguise fails the
    // allowlist (png is not a configured non-image extension either).
    expect(res.body.code).toBe('upload_type_not_allowed');
  });

  it('sanitizes an uploaded SVG, stripping scripts and event handlers (#61)', async () => {
    const settings = app.get(InstanceSettingsService);
    await settings.set('upload.svgPolicy', 'sanitize', 'test');
    const dirty = Buffer.from(
      '<svg xmlns="http://www.w3.org/2000/svg" onload="alert(1)">' +
        '<script>alert(2)</script><rect width="10" height="10"/></svg>',
    );
    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', dirty, 'diagram.svg')
      .expect(201);
    expect(uploaded.body.mimeType).toBe('image/svg+xml');

    const served = await api()
      .get(`/api/v1/media/${uploaded.body.id}`)
      .set('Cookie', ownerCookie)
      .buffer(true)
      .parse(binaryParser as unknown as ParseCallback)
      .expect(200);
    const cleaned = served.body.toString('utf8').toLowerCase();
    expect(cleaned).not.toContain('<script');
    expect(cleaned).not.toContain('onload');
    expect(cleaned).toContain('<rect');
    // SVG is always a download, never inline.
    expect(served.headers['content-disposition']).toContain('attachment');
  });

  it('rejects an SVG upload when the policy is reject (#61)', async () => {
    const settings = app.get(InstanceSettingsService);
    await settings.set('upload.svgPolicy', 'reject', 'test');
    try {
      const res = await api()
        .post(`/api/v1/ponds/${pondId}/files`)
        .set('Cookie', ownerCookie)
        .attach('file', Buffer.from('<svg xmlns="http://www.w3.org/2000/svg"/>'), 'x.svg')
        .expect(400);
      expect(res.body.code).toBe('upload_type_not_allowed');
    } finally {
      await settings.set('upload.svgPolicy', 'sanitize', 'test');
    }
  });

  it('rejects an oversize file with a distinct error from quota_exceeded', async () => {
    await setPondOverride('max_file_bytes', 10);
    try {
      const res = await api()
        .post(`/api/v1/ponds/${pondId}/files`)
        .set('Cookie', ownerCookie)
        .attach('file', pngBuffer('this payload is well beyond ten bytes'), 'big.png')
        .expect(413);
      expect(res.body.code).toBe('file_too_large');
      expect(res.body.details.limitBytes).toBe(10);
    } finally {
      await clearPondOverrides();
    }
  });

  it('rejects uploads that exceed the storage quota', async () => {
    await setPondOverride('max_file_bytes', 10_000);
    await setPondOverride('storage_bytes', 5);
    try {
      const res = await api()
        .post(`/api/v1/ponds/${pondId}/files`)
        .set('Cookie', ownerCookie)
        .attach('file', pngBuffer('needs more than five bytes of budget'), 'photo.png')
        .expect(403);
      expect(res.body.code).toBe('quota_exceeded');
      expect(res.body.details.quotaKey).toBe('storage_bytes');
    } finally {
      await clearPondOverrides();
    }
  });

  it('releases quota and removes the on-disk bytes on delete', async () => {
    const before = await prisma.pondUsage.findUnique({ where: { pondId } });
    const startUsage = Number(before?.storageBytesUsed ?? 0);

    const bytes = pngBuffer('to be deleted');
    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', bytes, 'delete-me.png')
      .expect(201);

    const afterUpload = await prisma.pondUsage.findUniqueOrThrow({ where: { pondId } });
    expect(Number(afterUpload.storageBytesUsed)).toBe(startUsage + bytes.length);

    const filePath = join(process.env.UPLOADS_DIR!, pondId, uploaded.body.id);
    expect(existsSync(filePath)).toBe(true);

    await api().delete(`/api/v1/files/${uploaded.body.id}`).set('Cookie', ownerCookie).expect(204);

    expect(existsSync(filePath)).toBe(false);
    const afterDelete = await prisma.pondUsage.findUniqueOrThrow({ where: { pondId } });
    expect(Number(afterDelete.storageBytesUsed)).toBe(startUsage);
    await api().get(`/api/v1/media/${uploaded.body.id}`).set('Cookie', ownerCookie).expect(404);
  });

  it('keeps a file reachable after its page is soft-deleted (no eager purge)', async () => {
    const page = await api()
      .post(`/api/v1/ponds/${pondId}/pages`)
      .set('Cookie', ownerCookie)
      .send({ title: `With Attachment ${suffix}` })
      .expect(201);

    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', pngBuffer('page-attached'), 'inline.png')
      .expect(201);
    // #27 does not expose pageId on the upload endpoint yet (it is set once
    // a future story tracks a page's embedded attachments) — associate it
    // directly to exercise the "stays until purge" guarantee now.
    await prisma.attachment.update({
      where: { id: uploaded.body.id },
      data: { pageId: page.body.id },
    });

    await api().delete(`/api/v1/pages/${page.body.id}`).set('Cookie', ownerCookie).expect(204);

    await api().get(`/api/v1/media/${uploaded.body.id}`).set('Cookie', ownerCookie).expect(200);
    const stillThere = await prisma.attachment.findUnique({ where: { id: uploaded.body.id } });
    expect(stillThere).not.toBeNull();
    expect(stillThere?.deletedAt).toBeNull();
  });

  it('lists a page attachment for the page and links it (#61)', async () => {
    const page = await api()
      .post(`/api/v1/ponds/${pondId}/pages`)
      .set('Cookie', ownerCookie)
      .send({ title: `Page Files ${suffix}` })
      .expect(201);

    const uploaded = await api()
      .post(`/api/v1/pages/${page.body.id}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', Buffer.from('%PDF-1.4 attached to a page'), 'report.pdf')
      .expect(201);
    expect(uploaded.body.pageId).toBe(page.body.id);

    const listed = await api()
      .get(`/api/v1/pages/${page.body.id}/files`)
      .set('Cookie', ownerCookie)
      .expect(200);
    const item = listed.body.find((f: { id: string }) => f.id === uploaded.body.id);
    expect(item).toBeDefined();
    expect(item.uploaderName).toBe(owner.displayName);
    expect(item.pageTitle).toBe(`Page Files ${suffix}`);
  });

  it('pond file manager reports usage, orphans, and page links (#61)', async () => {
    const page = await api()
      .post(`/api/v1/ponds/${pondId}/pages`)
      .set('Cookie', ownerCookie)
      .send({ title: `Manager Page ${suffix}` })
      .expect(201);
    const linked = await api()
      .post(`/api/v1/pages/${page.body.id}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', Buffer.from('%PDF-1.4 linked'), 'linked.pdf')
      .expect(201);
    const orphan = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', pngBuffer('orphan image'), 'orphan.png')
      .expect(201);

    const manager = await api()
      .get(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .expect(200);
    expect(manager.body.storageBytesLimit).toBeGreaterThan(0);
    const usage = await prisma.pondUsage.findUnique({ where: { pondId } });
    expect(manager.body.storageBytesUsed).toBe(Number(usage?.storageBytesUsed ?? 0));

    const linkedItem = manager.body.files.find((f: { id: string }) => f.id === linked.body.id);
    const orphanItem = manager.body.files.find((f: { id: string }) => f.id === orphan.body.id);
    expect(linkedItem.pageTitle).toBe(`Manager Page ${suffix}`);
    expect(orphanItem.pageTitle).toBeNull();
  });

  it('denies the pond file manager to a non-admin (#61)', async () => {
    await api().get(`/api/v1/ponds/${pondId}/files`).set('Cookie', outsiderCookie).expect(404);
  });

  it('hides foreign-pond files from download and delete (404, not 403)', async () => {
    const uploaded = await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', ownerCookie)
      .attach('file', pngBuffer('private'), 'private.png')
      .expect(201);

    await api().get(`/api/v1/media/${uploaded.body.id}`).set('Cookie', outsiderCookie).expect(404);
    await api()
      .delete(`/api/v1/files/${uploaded.body.id}`)
      .set('Cookie', outsiderCookie)
      .expect(404);
    await api()
      .post(`/api/v1/ponds/${pondId}/files`)
      .set('Cookie', outsiderCookie)
      .attach('file', pngBuffer('sneaky'), 'sneaky.png')
      .expect(404);
  });
});