import { describe, expect, it } from 'vitest';
import {
  buildKantineExport,
  KantineExportError,
  processKantineCsv,
} from './kantine-datev.pipeline';

const SETTINGS = { beraterNr: '1234567', mandantNr: '12345', lohnart: '1111' };
const HEADER = 'PersNr;Name;Menge;EK;Netto;ZuAb;MwSt;Zuschuss;Betrag;Von;Bis';
const ok = (nr: string, name: string, betrag: string, bis = '31.03.2026') =>
  `${nr};${name};1;1,00;1,00;0;0;0;${betrag};01.03.2026;${bis}`;

function csv(lines: string[], eol = '\r\n'): string {
  return [HEADER, ...lines].join(eol);
}

describe('processKantineCsv', () => {
  it('liest Windows-1252 mit Umlauten und CRLF', () => {
    const buf = Buffer.from(
      csv([ok('100', 'Müller, Jürgen', '7,94'), ok('200', 'Köhler', '51,5')]),
      'latin1',
    );
    const p = processKantineCsv(buf, SETTINGS);
    expect(p.rowCount).toBe(2);
    expect(p.abrechnungsMonat).toBe('03/2026');
    expect(p.totalCents).toBe(794 + 5150);
    expect(p.errors).toEqual([]);
    expect(p.canExport).toBe(true);
    expect(p.blockedReason).toBeNull();
  });

  it('liest UTF-8 mit BOM und LF gleich', () => {
    const body = csv([ok('100', 'Müller', '7,94')], '\n');
    const buf = Buffer.concat([Buffer.from([0xef, 0xbb, 0xbf]), Buffer.from(body, 'utf8')]);
    const p = processKantineCsv(buf, SETTINGS);
    expect(p.rowCount).toBe(1);
    expect(p.errors).toEqual([]);
  });

  it('zaehlt in der Summe nur Zeilen mit gueltigem Betrag', () => {
    const p = processKantineCsv(
      Buffer.from(csv([ok('100', 'A', '7,94'), ok('101', 'B', 'abc')])),
      SETTINGS,
    );
    expect(p.totalCents).toBe(794);
    expect(p.errors).toEqual([expect.objectContaining({ row: 3, code: 'betragFormat' })]);
    expect(p.canExport).toBe(false);
    expect(p.blockedReason).toBe('errors');
  });

  it('meldet zwei Monate als Warnung, nicht als Fehler', () => {
    const p = processKantineCsv(
      Buffer.from(csv([ok('100', 'A', '1,00'), `101;B;1;1;1;0;0;0;1,00;01.04.2026;30.04.2026`])),
      SETTINGS,
    );
    expect(p.warnings).toHaveLength(1);
    expect(p.errors).toEqual([]);
    expect(p.abrechnungsMonat).toBe('03/2026');
  });

  it('meldet eine Datei ohne Datenzeilen mit noRows', () => {
    const p = processKantineCsv(Buffer.from(csv([])), SETTINGS);
    expect(p.rowCount).toBe(0);
    expect(p.errors.map((e) => e.code)).toEqual(['noRows']);
    expect(p.canExport).toBe(false);
  });

  it('sperrt ohne Einstellungen mit settingsMissing', () => {
    const p = processKantineCsv(Buffer.from(csv([ok('100', 'A', '1,00')])), null);
    expect(p.canExport).toBe(false);
    expect(p.blockedReason).toBe('settingsMissing');
  });

  it('gibt keine Zeileninhalte in der Vorschau zurueck', () => {
    const p = processKantineCsv(Buffer.from(csv([ok('100', 'Geheimname', 'x')])), SETTINGS);
    expect(JSON.stringify(p)).not.toContain('Geheimname');
  });
});

describe('buildKantineExport', () => {
  it('erzeugt Dateiname und Base64-Inhalt', () => {
    const r = buildKantineExport(Buffer.from(csv([ok('100', 'A', '7,94')])), SETTINGS);
    expect(r.filename).toBe('LuG_1234567_12345_03_2026.sic');
    expect(r.mimeType).toBe('text/plain');
    expect(Buffer.from(r.content, 'base64').toString('utf8')).toBe(
      '1234567\t12345\t03/2026\t\t\t\t\t\t\t\t\r\n\t100\t\t1111\t-7.94\t\t\t\t\t\t\r\n',
    );
  });

  it('verweigert den Export bei Fehlern', () => {
    expect(() => buildKantineExport(Buffer.from(csv([ok('x', 'A', '7,94')])), SETTINGS)).toThrow(
      KantineExportError,
    );
    try {
      buildKantineExport(Buffer.from(csv([ok('x', 'A', '7,94')])), SETTINGS);
    } catch (e) {
      expect((e as KantineExportError).code).toBe('hasErrors');
    }
  });

  it('verweigert den Export ohne Einstellungen', () => {
    try {
      buildKantineExport(Buffer.from(csv([ok('100', 'A', '7,94')])), null);
      expect.unreachable();
    } catch (e) {
      expect((e as KantineExportError).code).toBe('settingsMissing');
    }
  });
});