import { beforeEach, describe, expect, it, vi } from 'vitest';
import * as nodemailer from 'nodemailer';
import { SettingsService } from './settings.service';
import { forTenant } from '../prisma/prisma-tenant.extension';

/**
 * SettingsService.spec — NEU (260911-gwh). Der Bereich `settings` hatte VOR
 * diesem Lauf KEINE Testdatei (Befund J). Zwei-Klienten-Nachbau, aber mit
 * einer GRENZE als Bauform (anders als `favorites`): der UNGEBUNDENE Nachbau
 * bietet fuer `smtpConfig` AUSSCHLIESSLICH `findFirst` (der Startpfad) —
 * KEIN `findUnique`, KEIN `upsert`; der GEBUNDENE Klient bietet
 * AUSSCHLIESSLICH `findUnique`/`upsert` — KEIN `findFirst`. Ein gebundener
 * Startpfad scheitert damit ebenso hart wie ein ungebundener Anfrageweg
 * ("X is not a function" statt eines stillen Fallbacks).
 *
 * `nodemailer` wird per `vi.mock` ersetzt — kein echter Transport (lokal
 * gibt es keinen `mailhog`).
 */
vi.mock('../prisma/prisma-tenant.extension', () => ({
  forTenant: vi.fn((unboundClient: any, tenantId: string) => unboundClient.__makeBoundClient(tenantId)),
}));

let mockVerify = vi.fn(async () => true);
let mockSendMail = vi.fn(async () => ({}));
vi.mock('nodemailer', () => ({
  createTransport: vi.fn(() => ({
    verify: (...args: unknown[]) => (mockVerify as any)(...args),
    sendMail: (...args: unknown[]) => (mockSendMail as any)(...args),
  })),
}));

interface FakeSmtpRow {
  id: string;
  tenantId: string;
  host: string;
  port: number;
  encryption: string;
  username: string | null;
  encryptedPassword: string | null;
  fromAddress: string;
  createdAt?: Date;
  updatedAt?: Date;
}

interface BoundCall {
  tenantId: string;
  model: 'smtpConfig';
  method: string;
}

function applySelect(row: Record<string, unknown>, select?: Record<string, boolean>) {
  if (!select) return { ...row };
  const out: Record<string, unknown> = {};
  for (const key of Object.keys(select)) {
    if (select[key]) out[key] = row[key];
  }
  return out;
}

function makeFakePrisma(rows: FakeSmtpRow[] = []) {
  const configs = new Map(rows.map((r) => [r.tenantId, { ...r }]));
  const boundCallLog: BoundCall[] = [];
  let autoId = rows.length;

  const unboundSmtpConfig = {
    findFirst: vi.fn(async () => {
      const first = configs.values().next().value;
      return first ? { ...first } : null;
    }),
  };

  function makeScopedSmtpConfig(tenantId: string) {
    return {
      findUnique: async ({ where, select }: any) => {
        boundCallLog.push({ tenantId, model: 'smtpConfig', method: 'findUnique' });
        const row = configs.get(where.tenantId);
        if (!row || row.tenantId !== tenantId) return null;
        return applySelect(row, select);
      },
      upsert: async ({ where, create, update, select }: any) => {
        boundCallLog.push({ tenantId, model: 'smtpConfig', method: 'upsert' });
        if (where.tenantId !== tenantId) return null;
        const existing = configs.get(tenantId);
        const record = existing
          ? { ...existing, ...update }
          : { id: `smtp-${++autoId}`, createdAt: new Date(), ...create };
        record.updatedAt = new Date();
        configs.set(tenantId, record);
        return applySelect(record, select);
      },
    };
  }

  const fake: any = {
    smtpConfig: unboundSmtpConfig,
    __configs: configs,
    __boundCallLog: boundCallLog,
    __makeBoundClient(tenantId: string) {
      return { smtpConfig: makeScopedSmtpConfig(tenantId) };
    },
  };
  return fake;
}

function expectBoundCall(prisma: any, tenantId: string, method: string) {
  const found = prisma.__boundCallLog.some(
    (c: BoundCall) => c.tenantId === tenantId && c.model === 'smtpConfig' && c.method === method,
  );
  expect(
    found,
    `erwarteter gebundener Aufruf smtpConfig.${method}(tenant=${tenantId}) fehlt im Protokoll: ${JSON.stringify(prisma.__boundCallLog)}`,
  ).toBe(true);
}

function makeFakeCrypto() {
  return {
    encrypt: vi.fn((s: string) => `enc(${s})`),
    decrypt: vi.fn((s: string) => s.slice(4, -1)),
  };
}

beforeEach(() => {
  vi.clearAllMocks();
  mockVerify = vi.fn(async () => true);
  mockSendMail = vi.fn(async () => ({}));
});

describe('SettingsService — Bindung an forTenant() (260911-gwh)', () => {
  it('scheitert an "X is not a function", wenn getSmtpConfig versehentlich ungebunden auf dem Basisclient laeuft (Falsifizierungsform)', () => {
    const prisma = makeFakePrisma();
    expect((prisma.smtpConfig as any).findUnique).toBeUndefined();
    expect((prisma.smtpConfig as any).upsert).toBeUndefined();
  });

  describe('getSmtpConfig', () => {
    it('liefert die Zeile mit encryptedPassword (fuer hasPassword), ohne Felder ausserhalb des select', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: 'user-a',
          encryptedPassword: 'enc(geheim)',
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.getSmtpConfig('t1');

      expect(result?.encryptedPassword).toBe('enc(geheim)');
      expect(result?.host).toBe('smtp-a.example.invalid');
      expectBoundCall(prisma, 't1', 'findUnique');
    });

    it('fremder Mandant: null', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: null,
          encryptedPassword: null,
          fromAddress: 'a@example.invalid',
        },
      ]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      const result = await service.getSmtpConfig('t2');

      expect(result).toBeNull();
    });
  });

  describe('saveSmtpConfig', () => {
    it('mit Kennwort: encrypt wird GENAU mit dem Klartext aufgerufen, upsert traegt encryptedPassword, Rueckgabe OHNE encryptedPassword', async () => {
      const prisma = makeFakePrisma();
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.saveSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        username: 'user-a',
        password: 'klartext-geheim',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(crypto.encrypt).toHaveBeenCalledWith('klartext-geheim');
      expect((result as any).encryptedPassword).toBeUndefined();
      const stored = prisma.__configs.get('t1');
      expect(stored.encryptedPassword).toBe('enc(klartext-geheim)');
      expectBoundCall(prisma, 't1', 'upsert');
      const logged = JSON.stringify(prisma.__boundCallLog);
      expect(logged).not.toContain('klartext-geheim');
    });

    it('ohne Kennwort (leer oder fehlend): encrypt NICHT aufgerufen, update traegt KEINEN Schluessel encryptedPassword, username fehlend -> null', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'alt.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: 'alt-user',
          encryptedPassword: 'enc(alt-geheim)',
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      await service.saveSmtpConfig('t1', {
        host: 'neu.example.invalid',
        port: 587,
        encryption: 'starttls',
        password: '',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(crypto.encrypt).not.toHaveBeenCalled();
      const stored = prisma.__configs.get('t1');
      expect(stored.encryptedPassword).toBe('enc(alt-geheim)'); // bestehendes bleibt
      expect(stored.username).toBeNull();
    });

    it('unter t2, wenn nur t1 eine Zeile hat: legt fuer t2 an, t1 bleibt unveraendert (Semantik nach der Bindung)', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: null,
          encryptedPassword: null,
          fromAddress: 'a@example.invalid',
        },
      ]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      await service.saveSmtpConfig('t2', {
        host: 'b.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'b@example.invalid',
      } as any);

      expect(prisma.__configs.get('t1').host).toBe('a.example.invalid');
      expect(prisma.__configs.get('t2').host).toBe('b.example.invalid');
    });
  });

  describe('getDecryptedSmtpConfig', () => {
    it('entschluesselt encryptedPassword, liefert die Form die tender-mail.service.ts erwartet', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: 'user-a',
          encryptedPassword: 'enc(geheim)',
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.getDecryptedSmtpConfig('t1');

      expect(crypto.decrypt).toHaveBeenCalledWith('enc(geheim)');
      expect(result).toEqual({
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        username: 'user-a',
        fromAddress: 'a@example.invalid',
        decryptedPassword: 'geheim',
      });
    });

    it('ohne encryptedPassword: decryptedPassword null, decrypt NICHT aufgerufen', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: null,
          encryptedPassword: null,
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.getDecryptedSmtpConfig('t1');

      expect(result?.decryptedPassword).toBeNull();
      expect(crypto.decrypt).not.toHaveBeenCalled();
    });

    it('T-GWH-01: fremder Mandant -> null, decrypt NICHT aufgerufen', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: 'user-a',
          encryptedPassword: 'enc(geheim)',
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.getDecryptedSmtpConfig('t2');

      expect(result).toBeNull();
      expect(crypto.decrypt).not.toHaveBeenCalled();
    });
  });

  describe('testSmtpConfig', () => {
    const storedRow: FakeSmtpRow = {
      id: 'smtp-a',
      tenantId: 't1',
      host: 'smtp-a.example.invalid',
      port: 587,
      encryption: 'starttls',
      username: 'user-a',
      encryptedPassword: 'enc(geheim)',
      fromAddress: 'a@example.invalid',
    };

    it('ohne Kennwort/Benutzername im DTO: greift auf die gespeicherten Werte zurueck, ruft verify auf, { success: true }', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      const result = await service.testSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(result).toEqual({ success: true });
      expect(mockVerify).toHaveBeenCalled();
      expect(mockSendMail).not.toHaveBeenCalled();
      expect(nodemailer.createTransport).toHaveBeenCalledWith(
        expect.objectContaining({ auth: { user: 'user-a', pass: 'geheim' } }),
      );
    });

    it('mit testTo: sendMail statt verify, from/to aus dto', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      await service.testSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'a@example.invalid',
        testTo: 'ziel@example.invalid',
      } as any);

      expect(mockSendMail).toHaveBeenCalledWith(
        expect.objectContaining({ from: 'a@example.invalid', to: 'ziel@example.invalid' }),
      );
      expect(mockVerify).not.toHaveBeenCalled();
    });

    it('verify wirft -> { success: false }, kein Wurf nach aussen', async () => {
      mockVerify = vi.fn(async () => {
        throw new Error('ECONNREFUSED');
      });
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      const result = await service.testSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(result.success).toBe(false);
    });

    it('fremder Mandant ohne Kennwort im DTO: auth ohne Benutzer, kein Fehler', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      await service.testSmtpConfig('t2', {
        host: 'x.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'x@example.invalid',
      } as any);

      expect(nodemailer.createTransport).toHaveBeenCalledWith(
        expect.objectContaining({ auth: undefined }),
      );
    });
  });

  describe('loadAnySmtpConfigForStartupTransport (Startpfad, bewusst ungebunden)', () => {
    it('laeuft ueber den UNGEBUNDENEN Nachbau (findFirst), liefert secure/requireTLS/entschluesseltes Kennwort', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 465,
          encryption: 'ssl-tls',
          username: 'user-a',
          encryptedPassword: 'enc(geheim)',
          fromAddress: 'a@example.invalid',
        },
      ]);
      const crypto = makeFakeCrypto();
      const service = new SettingsService(prisma as any, crypto as any);

      const result = await service.loadAnySmtpConfigForStartupTransport();

      expect(result).toEqual({
        host: 'smtp-a.example.invalid',
        port: 465,
        secure: true,
        requireTLS: false,
        username: 'user-a',
        password: 'geheim',
        fromAddress: 'a@example.invalid',
      });
    });

    it('requireTLS bei starttls', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: null,
          encryptedPassword: null,
          fromAddress: 'a@example.invalid',
        },
      ]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      const result = await service.loadAnySmtpConfigForStartupTransport();

      expect(result?.secure).toBe(false);
      expect(result?.requireTLS).toBe(true);
    });

    it('leerer Nachbau -> null', async () => {
      const prisma = makeFakePrisma([]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      const result = await service.loadAnySmtpConfigForStartupTransport();

      expect(result).toBeNull();
    });

    it('Null-Klienten-Nachweis: der Startpfad erzeugt KEINEN gebundenen Klienten (gemessen, nicht behauptet)', async () => {
      const prisma = makeFakePrisma([
        {
          id: 'smtp-a',
          tenantId: 't1',
          host: 'smtp-a.example.invalid',
          port: 587,
          encryption: 'starttls',
          username: null,
          encryptedPassword: null,
          fromAddress: 'a@example.invalid',
        },
      ]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      vi.mocked(forTenant).mockClear();
      await service.loadAnySmtpConfigForStartupTransport();

      expect(vi.mocked(forTenant).mock.calls.length).toBe(0);
    });
  });

  describe('Wachhund je Anfrageweg', () => {
    const storedRow: FakeSmtpRow = {
      id: 'smtp-a',
      tenantId: 't1',
      host: 'smtp-a.example.invalid',
      port: 587,
      encryption: 'starttls',
      username: 'user-a',
      encryptedPassword: 'enc(geheim)',
      fromAddress: 'a@example.invalid',
    };

    it('genau EIN gebundener Klient je Aufruf von getSmtpConfig/saveSmtpConfig/getDecryptedSmtpConfig', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      for (const call of [
        () => service.getSmtpConfig('t1'),
        () =>
          service.saveSmtpConfig('t1', {
            host: 'x.invalid',
            port: 587,
            encryption: 'starttls',
            fromAddress: 'x@invalid.de',
          } as any),
        () => service.getDecryptedSmtpConfig('t1'),
      ]) {
        vi.mocked(forTenant).mockClear();
        await call();
        expect(vi.mocked(forTenant).mock.calls.length).toBe(1);
      }
    });

    it('testSmtpConfig erzeugt genau einen gebundenen Klienten, wenn es auf gespeicherte Zugangsdaten zurueckgreift', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      vi.mocked(forTenant).mockClear();
      await service.testSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(vi.mocked(forTenant).mock.calls.length).toBe(1);
    });

    it('testSmtpConfig erzeugt KEINEN gebundenen Klienten, wenn Kennwort und Benutzername im DTO stehen', async () => {
      const prisma = makeFakePrisma([storedRow]);
      const service = new SettingsService(prisma as any, makeFakeCrypto() as any);

      vi.mocked(forTenant).mockClear();
      await service.testSmtpConfig('t1', {
        host: 'smtp-a.example.invalid',
        port: 587,
        encryption: 'starttls',
        username: 'anderer-user',
        password: 'anderes-kennwort',
        fromAddress: 'a@example.invalid',
      } as any);

      expect(vi.mocked(forTenant).mock.calls.length).toBe(0);
    });
  });
});