import * as fs from 'fs';
import { afterEach, describe, expect, it, vi } from 'vitest';
import { DkvService } from './dkv.service';

/**
 * DkvService.spec — RED-first (TDD) Nachweis fuer die Bindung an
 * forTenant() (260909-mir, Aufgabe 2/3). Dieser Bereich hatte VOR diesem
 * Durchlauf KEINE einzige Testdatei (Befund J) — dieser Fake ist deshalb die
 * Voraussetzung dafuer, dass irgendeine Aussage dieses Plans nachpruefbar
 * ist, nicht eine Zugabe.
 *
 * Zwei-Klienten-Nachweis (Muster aus groups.service.spec.ts /
 * tender-triage.service.spec.ts): `__makeBoundClient(tenantId)` wrappt
 * DIESELBEN In-Memory-Maps mit einer protokollierenden Schicht je Modell.
 * Der ungebundene Fake protokolliert NICHT, der gebundene schon — eine
 * vergessene Bindung wird dadurch sichtbar, ein reiner Identitaets-Mock
 * (`(p) => p`, der ldap-Fehler) wuerde das nicht leisten.
 *
 * Der Fake wird in Aufgabe 3 um `dkvVehicleMaster`/`dkvInvoiceHistory`
 * ERWEITERT, nicht ersetzt (siehe unten in makeFakePrisma()).
 */

vi.mock('../prisma/prisma-tenant.extension', () => ({
  forTenant: vi.fn((prisma: any, tenantId: string) => prisma.__makeBoundClient(tenantId)),
}));

// `import * as fs from 'fs'` under ESM has a non-configurable module
// namespace — vi.spyOn(fs, 'existsSync') fails with "Cannot redefine
// property". vi.mock() replaces the module at import time instead, which
// works regardless of namespace configurability (Tests 8-10, Aufgabe 3).
vi.mock('fs', async (importOriginal) => {
  const actual = await importOriginal<typeof import('fs')>();
  return { ...actual, existsSync: vi.fn(), readFileSync: vi.fn() };
});

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

function makeFakePrisma() {
  const configs = new Map<string, any>(); // key: tenantId
  const boundCallLog: { tenantId: string; model: string; method: string }[] = [];

  const dkvModuleConfig = {
    findFirst: vi.fn(async ({ select }: { select?: Record<string, boolean> } = {}) => {
      // Arbitrary-but-first row — die Form, die der Planer-Startpfad heute
      // benutzt (findFirst() ganz ohne Bedingung). Map bewahrt
      // Einfuegereihenfolge, das genuegt fuer "irgendeine" Zeile.
      const first = configs.values().next().value;
      return first ? _applySelect(first, select) : null;
    }),
    findUnique: vi.fn(
      async ({
        where,
        select,
      }: {
        where: { tenantId: string };
        select?: Record<string, boolean>;
      }) => {
        const row = configs.get(where.tenantId);
        return row ? _applySelect(row, select) : null;
      },
    ),
    upsert: vi.fn(
      async ({
        where,
        create,
        update,
        select,
      }: {
        where: { tenantId: string };
        create: Record<string, unknown>;
        update: Record<string, unknown>;
        select?: Record<string, boolean>;
      }) => {
        const existing = configs.get(where.tenantId);
        const record = existing
          ? { ...existing, ...update }
          : { id: `cfg-${configs.size + 1}`, ...create };
        configs.set(where.tenantId, record);
        return _applySelect(record, select);
      },
    ),
  };

  // ─── dkvVehicleMaster (Aufgabe 3) ─────────────────────────────────────────
  const vehicles = new Map<string, any>(); // key: id
  let vehicleAutoId = 0;

  const dkvVehicleMaster = {
    findMany: vi.fn(async ({ where }: { where?: { tenantId?: string } } = {}) => {
      return Array.from(vehicles.values()).filter(
        (v) => !where?.tenantId || v.tenantId === where.tenantId,
      );
    }),
    create: vi.fn(async ({ data }: { data: Record<string, unknown> }) => {
      const id = `veh-${++vehicleAutoId}`;
      const record = { id, ...data };
      vehicles.set(id, record);
      return record;
    }),
    findFirst: vi.fn(async ({ where }: { where: { id: string; tenantId: string } }) => {
      const row = vehicles.get(where.id);
      return row && row.tenantId === where.tenantId ? row : null;
    }),
    update: vi.fn(async ({ where, data }: { where: { id: string }; data: Record<string, unknown> }) => {
      const existing = vehicles.get(where.id);
      const record = { ...existing, ...data };
      vehicles.set(where.id, record);
      return record;
    }),
    delete: vi.fn(async ({ where }: { where: { id: string } }) => {
      const existing = vehicles.get(where.id);
      vehicles.delete(where.id);
      return existing;
    }),
    deleteMany: vi.fn(async ({ where }: { where?: { tenantId?: string } } = {}) => {
      let count = 0;
      for (const [id, v] of vehicles) {
        if (!where?.tenantId || v.tenantId === where.tenantId) {
          vehicles.delete(id);
          count++;
        }
      }
      return { count };
    }),
    createMany: vi.fn(async ({ data }: { data: Record<string, unknown>[] }) => {
      for (const d of data) {
        const id = `veh-${++vehicleAutoId}`;
        vehicles.set(id, { id, ...d });
      }
      return { count: data.length };
    }),
    upsert: vi.fn(
      async ({
        where,
        create,
        update,
      }: {
        where: { tenantId_kennzeichen: { tenantId: string; kennzeichen: string } };
        create: Record<string, unknown>;
        update: Record<string, unknown>;
      }) => {
        const key = where.tenantId_kennzeichen;
        const existing = Array.from(vehicles.values()).find(
          (v) => v.tenantId === key.tenantId && v.kennzeichen === key.kennzeichen,
        );
        if (existing) {
          const record = { ...existing, ...update };
          vehicles.set(existing.id, record);
          return record;
        }
        const id = `veh-${++vehicleAutoId}`;
        const record = { id, ...create };
        vehicles.set(id, record);
        return record;
      },
    ),
  };

  // ─── dkvInvoiceHistory (Aufgabe 3) ────────────────────────────────────────
  const history = new Map<string, any>(); // key: id
  let historyAutoId = 0;

  const dkvInvoiceHistory = {
    findMany: vi.fn(
      async ({
        where,
        skip,
        take,
      }: { where?: { tenantId?: string }; skip?: number; take?: number } = {}) => {
        let rows = Array.from(history.values()).filter(
          (h) => !where?.tenantId || h.tenantId === where.tenantId,
        );
        if (typeof skip === 'number') rows = rows.slice(skip);
        if (typeof take === 'number') rows = rows.slice(0, take);
        return rows;
      },
    ),
    count: vi.fn(async ({ where }: { where?: { tenantId?: string } } = {}) => {
      return Array.from(history.values()).filter(
        (h) => !where?.tenantId || h.tenantId === where.tenantId,
      ).length;
    }),
    create: vi.fn(async ({ data }: { data: Record<string, unknown> }) => {
      const id = `hist-${++historyAutoId}`;
      const record = { id, ...data };
      history.set(id, record);
      return record;
    }),
    findFirst: vi.fn(
      async ({
        where,
      }: {
        where: { tenantId?: string; exportFilename?: string };
      }) => {
        return (
          Array.from(history.values()).find(
            (h) =>
              (!where.tenantId || h.tenantId === where.tenantId) &&
              (!where.exportFilename || h.exportFilename === where.exportFilename),
          ) ?? null
        );
      },
    ),
  };

  const fake: any = {
    dkvModuleConfig,
    dkvVehicleMaster,
    dkvInvoiceHistory,
    __boundCallLog: boundCallLog,
    __seedConfig(tenantId: string, row: Record<string, unknown>) {
      configs.set(tenantId, { tenantId, ...row });
    },
    __seedVehicle(row: { id: string; tenantId: string; kennzeichen: string; marke?: string; modell?: string; fahrer?: string }) {
      vehicles.set(row.id, { marke: '', modell: '', fahrer: '', ...row });
    },
    __seedHistory(row: { id: string; tenantId: string; exportFilename?: string | null }) {
      history.set(row.id, {
        rechnungsnummer: 'RG-TEST',
        anzahlFahrzeuge: 0,
        anzahlTransaktionen: 0,
        status: 'Verarbeitet',
        exportFilename: null,
        ...row,
      });
    },
    __makeBoundClient(tenantId: string) {
      const wrapModel = (model: Record<string, any>, modelName: string, methods: string[]) => {
        const wrapped: any = {};
        for (const method of methods) {
          wrapped[method] = async (...args: any[]) => {
            boundCallLog.push({ tenantId, model: modelName, method });
            return model[method](...args);
          };
        }
        return wrapped;
      };
      return {
        dkvModuleConfig: wrapModel(dkvModuleConfig, 'dkvModuleConfig', ['findFirst', 'findUnique', 'upsert']),
        dkvVehicleMaster: wrapModel(dkvVehicleMaster, 'dkvVehicleMaster', [
          'findMany',
          'create',
          'findFirst',
          'update',
          'delete',
          'deleteMany',
          'createMany',
          'upsert',
        ]),
        dkvInvoiceHistory: wrapModel(dkvInvoiceHistory, 'dkvInvoiceHistory', [
          'findMany',
          'count',
          'create',
          'findFirst',
        ]),
      };
    },
  };

  return fake;
}

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

/** Schlichte Attrappen fuer die uebrigen Konstruktor-Abhaengigkeiten von DkvService. */
function makeFakeCrypto(overrides: Partial<{ encrypt: any; decrypt: any }> = {}) {
  return {
    encrypt: overrides.encrypt ?? vi.fn((plain: string) => `enc(${plain})`),
    decrypt: overrides.decrypt ?? vi.fn((stored: string) => stored.replace(/^enc\(/, '').replace(/\)$/, '')),
  };
}

function makeDkvService(
  prisma: any,
  overrides: Partial<{
    encrypt: any;
    decrypt: any;
    parser: any;
    exporter: any;
    mailer: any;
    imapProvider: any;
    exchangeProvider: any;
  }> = {},
) {
  const crypto = makeFakeCrypto(overrides);
  const parser = overrides.parser ?? ({} as any);
  const exporter = overrides.exporter ?? ({} as any);
  const mailer = overrides.mailer ?? ({ sendExportEmail: vi.fn() } as any);
  const imapProvider =
    overrides.imapProvider ??
    ({ testConnection: vi.fn(async () => ({ success: true })), fetchPdfAttachments: vi.fn(async () => []) } as any);
  const exchangeProvider =
    overrides.exchangeProvider ?? ({ testConnection: vi.fn(async () => ({ success: true })) } as any);

  const service = new DkvService(
    prisma,
    crypto as any,
    parser,
    exporter,
    mailer,
    imapProvider,
    exchangeProvider,
  );
  return { service, crypto };
}

describe('DkvService — Bindung an forTenant() (260909-mir)', () => {
  it('Test 1: getConfigForApi(tenantId) — beide Lesezugriffe auf dkvModuleConfig stehen im Bindungsprotokoll unter genau diesem Mandanten', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedConfig('t1', { id: 'cfg-1', protocol: 'imap', isActive: true, encryptedInboxCreds: null });
    const { service } = makeDkvService(prisma);

    await service.getConfigForApi('t1');

    const configCalls = prisma.__boundCallLog.filter(
      (c: any) => c.tenantId === 't1' && c.model === 'dkvModuleConfig' && c.method === 'findUnique',
    );
    expect(
      configCalls.length,
      `erwarte mindestens zwei gebundene findUnique-Aufrufe (sicherer + roher Lesezugriff) fuer t1, gefunden: ${JSON.stringify(prisma.__boundCallLog)}`,
    ).toBeGreaterThanOrEqual(2);
  });

  it('Test 2: getConfigForApi eines Mandanten liefert NICHT die Konfiguration eines zweiten Mandanten, wenn beide im Speicher liegen', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedConfig('t1', { id: 'cfg-1', protocol: 'imap', isActive: true, host: 'mail-a.example.invalid', encryptedInboxCreds: null });
    prisma.__seedConfig('t2', { id: 'cfg-2', protocol: 'imap', isActive: true, host: 'mail-b.example.invalid', encryptedInboxCreds: null });
    const { service } = makeDkvService(prisma);

    const configForT1 = await service.getConfigForApi('t1');

    expect(configForT1?.host).toBe('mail-a.example.invalid');
    expect(configForT1?.tenantId).toBe('t1');
  });

  it('Test 3: saveConfig(tenantId, dto) mit gesetztem Benutzernamen und LEEREM Passwort — Lese- und Schreibzugriff sind gebunden, das gespeicherte Passwort bleibt unveraendert', async () => {
    const prisma = makeFakePrisma();
    const crypto = makeFakeCrypto();
    prisma.__seedConfig('t1', {
      id: 'cfg-1',
      protocol: 'imap',
      isActive: true,
      encryptedInboxCreds: crypto.encrypt(JSON.stringify({ username: 'alt-user', password: 'geheim-123' })),
    });
    const { service } = makeDkvService(prisma, { encrypt: crypto.encrypt, decrypt: crypto.decrypt });

    await service.saveConfig('t1', {
      protocol: 'imap',
      encryption: 'ssl-tls',
      username: 'neu-user',
      password: '',
    } as any);

    expectBoundCall(prisma, 't1', 'dkvModuleConfig', 'findUnique');
    expectBoundCall(prisma, 't1', 'dkvModuleConfig', 'upsert');

    const raw = await prisma.dkvModuleConfig.findUnique({ where: { tenantId: 't1' } });
    const rawCreds = JSON.parse(crypto.decrypt(raw.encryptedInboxCreds));
    expect(rawCreds.password).toBe('geheim-123');
    expect(rawCreds.username).toBe('neu-user');
  });

  it('Test 4: testConnection(tenantId, dto) mit leerem Passwort — der Rueckgriff auf die gespeicherten Zugangsdaten steht gebunden im Protokoll', async () => {
    const prisma = makeFakePrisma();
    const crypto = makeFakeCrypto();
    prisma.__seedConfig('t1', {
      id: 'cfg-1',
      protocol: 'imap',
      isActive: true,
      encryptedInboxCreds: crypto.encrypt(JSON.stringify({ username: 'user-a', password: 'geheim-123' })),
    });
    const { service } = makeDkvService(prisma, { encrypt: crypto.encrypt, decrypt: crypto.decrypt });

    await service.testConnection('t1', {
      protocol: 'imap',
      encryption: 'ssl-tls',
      password: '',
    } as any);

    expectBoundCall(prisma, 't1', 'dkvModuleConfig', 'findUnique');
  });

  it('Test 5: die Verarbeitungsstrecke liest ihre Konfiguration gebunden; bei fehlender Konfiguration bricht sie wie bisher still ab', async () => {
    const prisma = makeFakePrisma();
    // Kein __seedConfig fuer t1 — die Konfiguration fehlt bewusst.
    const { service } = makeDkvService(prisma);

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

    expectBoundCall(prisma, 't1', 'dkvModuleConfig', 'findUnique');
    // Verhalten bleibt unveraendert: kein Fehler, checkNow meldet 'ok' —
    // die Rechnungsverarbeitung stellt fuer diesen Mandanten still die
    // Arbeit ein (Befund K, Stelle 2), das wird hier nur festgeschrieben.
    expect(result.status).toBe('ok');
  });

  it('Test 6: der bewusst uebergreifende Planer-Startpfad steht NICHT im Bindungsprotokoll — Fehlen der Bindung ist hier die bestandene Erwartung, NICHT spaeter "reparieren"', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedConfig('t1', { id: 'cfg-1', protocol: 'imap', isActive: true, encryptedInboxCreds: 'enc(egal)' });
    const { service } = makeDkvService(prisma);

    await service.loadAnyActiveConfigForScheduler();

    expect(
      prisma.__boundCallLog.length,
      `der Planer-Startpfad darf KEINEN gebundenen Aufruf erzeugen, gefunden: ${JSON.stringify(prisma.__boundCallLog)}`,
    ).toBe(0);
  });

  it('Test 7: der Planer-Startpfad liefert die verschluesselten Zugangsdaten NICHT mit (Befund D — Entlastung wird festgeschrieben, nicht geglaubt)', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedConfig('t1', {
      id: 'cfg-1',
      protocol: 'imap',
      isActive: true,
      encryptedInboxCreds: 'enc(sollte-nie-hier-auftauchen)',
    });
    const { service } = makeDkvService(prisma);

    const result = await service.loadAnyActiveConfigForScheduler();

    expect(result).not.toBeNull();
    expect((result as any).encryptedInboxCreds).toBeUndefined();
  });

  // ─── Aufgabe 3 (260909-mir): dkvVehicleMaster / dkvInvoiceHistory / getExportFile ───

  afterEach(() => {
    vi.restoreAllMocks();
  });

  it('Test 1: listVehicles/createVehicle stehen gebunden im Protokoll und liefern bzw. schreiben nur unter dem uebergebenen Mandanten', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedVehicle({ id: 'veh-a1', tenantId: 't1', kennzeichen: 'A-ONLY-1' });
    prisma.__seedVehicle({ id: 'veh-b1', tenantId: 't2', kennzeichen: 'B-ONLY-1' });
    const { service } = makeDkvService(prisma);

    const listed = await service.listVehicles('t1');
    expect(listed).toHaveLength(1);
    expect(listed[0].tenantId).toBe('t1');

    await service.createVehicle('t1', { kennzeichen: 'NEU-1', marke: 'X', modell: 'Y', fahrer: 'Z' } as any);

    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'findMany');
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'create');
    const listedAgain = await service.listVehicles('t1');
    expect(listedAgain).toHaveLength(2);
    expect(listedAgain.every((v: any) => v.tenantId === 't1')).toBe(true);
  });

  it('Test 2: updateVehicle/deleteVehicle — BEIDE Anweisungen (Besitzpruefung und Schreibzugriff) stehen gebunden im Protokoll', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedVehicle({ id: 'veh-a1', tenantId: 't1', kennzeichen: 'A-ONLY-1' });
    prisma.__seedVehicle({ id: 'veh-a2', tenantId: 't1', kennzeichen: 'A-ONLY-2' });
    const { service } = makeDkvService(prisma);

    await service.updateVehicle('t1', 'veh-a1', { marke: 'Neu' } as any);
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'findFirst');
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'update');

    await service.deleteVehicle('t1', 'veh-a2');
    const deleteFindFirstCalls = prisma.__boundCallLog.filter(
      (c: any) => c.tenantId === 't1' && c.model === 'dkvVehicleMaster' && c.method === 'findFirst',
    );
    expect(deleteFindFirstCalls.length).toBeGreaterThanOrEqual(2);
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'delete');
  });

  it('Test 3: updateVehicle/deleteVehicle auf ein Fahrzeug eines FREMDEN Mandanten werfen weiterhin die vorhandene NotFoundException', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedVehicle({ id: 'veh-b1', tenantId: 't2', kennzeichen: 'B-ONLY-1' });
    const { service } = makeDkvService(prisma);

    await expect(service.updateVehicle('t1', 'veh-b1', { marke: 'X' } as any)).rejects.toThrow('Vehicle not found');
    await expect(service.deleteVehicle('t1', 'veh-b1')).rejects.toThrow('Vehicle not found');
  });

  it('Test 4: importVehiclesCsv in beiden Modi — jede Anweisung steht gebunden im Protokoll; der Ersetzen-Modus loescht ausschliesslich Fahrzeuge des eigenen Mandanten', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedVehicle({ id: 'veh-a1', tenantId: 't1', kennzeichen: 'ALT-1' });
    prisma.__seedVehicle({ id: 'veh-b1', tenantId: 't2', kennzeichen: 'B-ONLY-1' });
    const { service } = makeDkvService(prisma);

    const csv = 'Kennzeichen;Marke;Modell;Fahrer\nNEU-1;Marke;Modell;Fahrer';
    await service.importVehiclesCsv('t1', csv, 'replace');

    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'deleteMany');
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'createMany');

    const t1Vehicles = await service.listVehicles('t1');
    const t2Vehicles = await service.listVehicles('t2');
    expect(t1Vehicles.map((v: any) => v.kennzeichen)).toEqual(['NEU-1']);
    expect(t2Vehicles).toHaveLength(1); // t2's vehicle survived the t1-scoped replace

    const csvMerge = 'Kennzeichen;Marke;Modell;Fahrer\nNEU-1;Marke2;Modell2;Fahrer2\nWEITERES-1;M;M;F';
    await service.importVehiclesCsv('t1', csvMerge, 'merge');
    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'upsert');
  });

  it('Test 5: getHistory — beide parallel gestarteten Abfragen stehen gebunden im Protokoll, die Gesamtzahl zaehlt nur eigene Zeilen', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedHistory({ id: 'hist-a1', tenantId: 't1' });
    prisma.__seedHistory({ id: 'hist-a2', tenantId: 't1' });
    prisma.__seedHistory({ id: 'hist-b1', tenantId: 't2' });
    const { service } = makeDkvService(prisma);

    const result = await service.getHistory('t1', 1, 20);

    expect(result.total).toBe(2);
    expect(result.items).toHaveLength(2);
    expectBoundCall(prisma, 't1', 'dkvInvoiceHistory', 'findMany');
    expectBoundCall(prisma, 't1', 'dkvInvoiceHistory', 'count');
  });

  it('Test 6: die beiden Historien-Schreibzugriffe der Verarbeitungsstrecke (Erfolgsfall und Zerlegungsfehler) stehen gebunden im Protokoll', async () => {
    // Erfolgsfall
    const prismaOk = makeFakePrisma();
    prismaOk.__seedConfig('t1', {
      id: 'cfg-1',
      protocol: 'imap',
      isActive: true,
      host: 'mail.example.invalid',
      folder: 'INBOX',
      encryptedInboxCreds: 'enc({"username":"u","password":"p"})',
    });
    const email = { subject: 'RG', uid: 1, attachments: [{ buffer: Buffer.from('pdf-bytes') }] };
    const parserOk = {
      parsePdf: vi.fn(async () => ({
        vehicles: [],
        rechnungsnummer: 'RG-1',
        rechnungsdatum: '01.01.2026',
      })),
    };
    const exporter = {
      buildExcelBuffer: vi.fn(() => Buffer.from('xlsx')),
      writeAndPrune: vi.fn(() => 'RG-DKV-RG-1-260101.xlsx'),
      resolveFahrzeug: vi.fn(() => ''),
    };
    const imapProvider = { fetchPdfAttachments: vi.fn(async () => [email]) };
    const { service: serviceOk } = makeDkvService(prismaOk, { parser: parserOk, exporter, imapProvider });

    await serviceOk.checkNow('t1');

    expectBoundCall(prismaOk, 't1', 'dkvInvoiceHistory', 'create');

    // Zerlegungsfehler-Fall
    const prismaFail = makeFakePrisma();
    prismaFail.__seedConfig('t1', {
      id: 'cfg-2',
      protocol: 'imap',
      isActive: true,
      host: 'mail.example.invalid',
      folder: 'INBOX',
      encryptedInboxCreds: 'enc({"username":"u","password":"p"})',
    });
    const parserFail = { parsePdf: vi.fn(async () => { throw new Error('kaputt'); }) };
    const imapProviderFail = { fetchPdfAttachments: vi.fn(async () => [email]) };
    const { service: serviceFail } = makeDkvService(prismaFail, {
      parser: parserFail,
      exporter,
      imapProvider: imapProviderFail,
    });

    await serviceFail.checkNow('t1');

    expectBoundCall(prismaFail, 't1', 'dkvInvoiceHistory', 'create');
  });

  it('Test 7: der gebuendelte Lesezugriff auf die Fahrzeugstammdaten beim Aufbau der Ausfuhrzeilen steht gebunden im Protokoll und zieht keine Fahrzeuge eines zweiten Mandanten in die Ausfuhrdatei', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedConfig('t1', {
      id: 'cfg-1',
      protocol: 'imap',
      isActive: true,
      host: 'mail.example.invalid',
      folder: 'INBOX',
      encryptedInboxCreds: 'enc({"username":"u","password":"p"})',
    });
    prisma.__seedVehicle({ id: 'veh-a1', tenantId: 't1', kennzeichen: 'A-1', marke: 'MarkeA', modell: 'ModellA', fahrer: 'FahrerA' });
    prisma.__seedVehicle({ id: 'veh-b1', tenantId: 't2', kennzeichen: 'A-1', marke: 'FREMD', modell: 'FREMD', fahrer: 'FREMD-Fahrer' });

    const email = { subject: 'RG', uid: 1, attachments: [{ buffer: Buffer.from('pdf-bytes') }] };
    let capturedRows: any[] | null = null;
    const parser = {
      parsePdf: vi.fn(async () => ({
        vehicles: [{ kennzeichen: 'A-1', transactions: [{ lieferdatum: '01.01.2026', ort: 'Ort', kilometerstand: 100 }] }],
        rechnungsnummer: 'RG-1',
        rechnungsdatum: '01.01.2026',
      })),
    };
    const exporter = {
      buildExcelBuffer: vi.fn((rows: any[]) => {
        capturedRows = rows;
        return Buffer.from('xlsx');
      }),
      writeAndPrune: vi.fn(() => 'RG-DKV-RG-1-260101.xlsx'),
      resolveFahrzeug: vi.fn((v: any) => `${v.marke}/${v.modell}/${v.kennzeichen}`),
    };
    const imapProvider = { fetchPdfAttachments: vi.fn(async () => [email]) };
    const { service } = makeDkvService(prisma, { parser, exporter, imapProvider });

    await service.checkNow('t1');

    expectBoundCall(prisma, 't1', 'dkvVehicleMaster', 'findMany');
    expect(capturedRows).not.toBeNull();
    expect(capturedRows![0].fahrer).toBe('FahrerA');
    expect(capturedRows![0].fahrer).not.toBe('FREMD-Fahrer');
  });

  it('Test 8: getExportFile liefert eine Datei, zu der eine Historienzeile DIESES Mandanten mit passendem Dateinamen existiert', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedHistory({ id: 'hist-a1', tenantId: 't1', exportFilename: 'RG-DKV-TEST-A.xlsx' });
    const { service } = makeDkvService(prisma);

    vi.mocked(fs.existsSync).mockReturnValue(true);
    vi.mocked(fs.readFileSync).mockReturnValue(Buffer.from('xlsx-bytes'));

    const buffer = await service.getExportFile('t1', 'RG-DKV-TEST-A.xlsx');

    expect(buffer.toString()).toBe('xlsx-bytes');
  });

  it('Test 9: getExportFile verweigert dieselbe Datei einem ZWEITEN Mandanten mit der vorhandenen NotFoundException, obwohl die Datei existiert und das Namensmuster besteht (Befund E — die geschlossene Luecke)', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedHistory({ id: 'hist-a1', tenantId: 't1', exportFilename: 'RG-DKV-TEST-A.xlsx' });
    const { service } = makeDkvService(prisma);

    vi.mocked(fs.existsSync).mockReturnValue(true);
    vi.mocked(fs.readFileSync).mockReturnValue(Buffer.from('xlsx-bytes'));

    await expect(service.getExportFile('t2', 'RG-DKV-TEST-A.xlsx')).rejects.toThrow(
      'Export file not found: RG-DKV-TEST-A.xlsx',
    );
  });

  it('Test 10: der Riegel laeuft ueber einen GEBUNDENEN Lesezugriff auf die Historie — im Bindungsprotokoll nachweisbar, nicht nur am Ergebnis', async () => {
    const prisma = makeFakePrisma();
    prisma.__seedHistory({ id: 'hist-a1', tenantId: 't1', exportFilename: 'RG-DKV-TEST-A.xlsx' });
    const { service } = makeDkvService(prisma);

    vi.mocked(fs.existsSync).mockReturnValue(true);
    vi.mocked(fs.readFileSync).mockReturnValue(Buffer.from('xlsx-bytes'));

    await service.getExportFile('t1', 'RG-DKV-TEST-A.xlsx');

    expectBoundCall(prisma, 't1', 'dkvInvoiceHistory', 'findFirst');
  });
});