Add CFDI XML parser and invoice import services with tests

Implement Task 3 (CFDI Parser) and Task 4 (Invoice Import) following TDD:
- CFDI parser extracts UUID, emisor, fecha, totals, and conceptos from CFDI 4.0 XML
- Import service inserts parsed invoice data into SQLite with duplicate detection
  and cross-references catalogo_intercambios for part number lookups
- All 12 tests pass (5 parser + 3 import + 4 existing database tests)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/services/cfdi-parser.js

@@ -0,0 +1,49 @@
+const fs = require('fs');
+const { XMLParser } = require('fast-xml-parser');
+
+const parser = new XMLParser({
+  ignoreAttributes: false,
+  attributeNamePrefix: '@_',
+  isArray: (name) => {
+    return name === 'cfdi:Concepto';
+  },
+});
+
+function parseCfdiFile(filePath) {
+  const xml = fs.readFileSync(filePath, 'utf-8');
+  return parseCfdiXml(xml);
+}
+
+function parseCfdiXml(xml) {
+  const parsed = parser.parse(xml);
+  const comprobante = parsed['cfdi:Comprobante'];
+
+  const emisor = comprobante['cfdi:Emisor'];
+  const conceptosNode = comprobante['cfdi:Conceptos']['cfdi:Concepto'];
+  const complemento = comprobante['cfdi:Complemento'];
+
+  const timbre = complemento['tfd:TimbreFiscalDigital'];
+  const uuid = timbre['@_UUID'];
+
+  const conceptosList = Array.isArray(conceptosNode) ? conceptosNode : [conceptosNode];
+  const conceptos = conceptosList.map((c) => ({
+    claveProdServ: c['@_ClaveProdServ'],
+    noIdentificacion: c['@_NoIdentificacion'] || '',
+    descripcion: c['@_Descripcion'],
+    cantidad: parseFloat(c['@_Cantidad']),
+    valorUnitario: parseFloat(c['@_ValorUnitario']),
+    importe: parseFloat(c['@_Importe']),
+  }));
+
+  return {
+    uuid,
+    rfcEmisor: emisor['@_Rfc'],
+    nombreEmisor: emisor['@_Nombre'],
+    fecha: comprobante['@_Fecha'],
+    subtotal: parseFloat(comprobante['@_SubTotal']),
+    total: parseFloat(comprobante['@_Total']),
+    conceptos,
+  };
+}
+
+module.exports = { parseCfdiFile, parseCfdiXml };

src/services/import-service.js

@@ -0,0 +1,65 @@
+const { parseCfdiFile } = require('./cfdi-parser');
+
+function importXmlFile(db, filePath) {
+  let parsed;
+  try {
+    parsed = parseCfdiFile(filePath);
+  } catch (err) {
+    return { success: false, reason: 'parse_error', error: err.message };
+  }
+
+  const existing = db.prepare('SELECT id FROM facturas WHERE uuid = ?').get(parsed.uuid);
+  if (existing) {
+    return { success: false, reason: 'duplicate', uuid: parsed.uuid };
+  }
+
+  const insertFactura = db.prepare(`
+    INSERT INTO facturas (uuid, rfc_emisor, nombre_emisor, fecha, subtotal, total, xml_path)
+    VALUES (?, ?, ?, ?, ?, ?, ?)
+  `);
+
+  const insertConcepto = db.prepare(`
+    INSERT INTO conceptos (factura_id, clave_prod_serv, no_identificacion, descripcion, cantidad, valor_unitario, importe, intercambio)
+    VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+  `);
+
+  const getIntercambio = db.prepare(
+    'SELECT no_parte_intercambio FROM catalogo_intercambios WHERE no_parte_proveedor = ?'
+  );
+
+  const transaction = db.transaction(() => {
+    const { lastInsertRowid } = insertFactura.run(
+      parsed.uuid,
+      parsed.rfcEmisor,
+      parsed.nombreEmisor,
+      parsed.fecha,
+      parsed.subtotal,
+      parsed.total,
+      filePath
+    );
+
+    for (const concepto of parsed.conceptos) {
+      const intercambioRow = getIntercambio.get(concepto.noIdentificacion);
+      const intercambio = intercambioRow ? intercambioRow.no_parte_intercambio : null;
+
+      insertConcepto.run(
+        lastInsertRowid,
+        concepto.claveProdServ,
+        concepto.noIdentificacion,
+        concepto.descripcion,
+        concepto.cantidad,
+        concepto.valorUnitario,
+        concepto.importe,
+        intercambio
+      );
+    }
+
+    return lastInsertRowid;
+  });
+
+  transaction();
+
+  return { success: true, uuid: parsed.uuid };
+}
+
+module.exports = { importXmlFile };

tests/cfdi-parser.test.js

@@ -0,0 +1,69 @@
+import { describe, it, expect } from 'vitest';
+import path from 'path';
+import fs from 'fs';
+import { fileURLToPath } from 'url';
+import { parseCfdiFile } from '../src/services/cfdi-parser.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+describe('CFDI Parser', () => {
+  const fixturePath = path.join(__dirname, 'fixtures', 'sample-cfdi.xml');
+
+  it('should extract UUID from TimbreFiscalDigital', () => {
+    const result = parseCfdiFile(fixturePath);
+    expect(result.uuid).toBe('6F8A29C3-1234-4567-8901-ABCDEF123456');
+  });
+
+  it('should extract emisor data', () => {
+    const result = parseCfdiFile(fixturePath);
+    expect(result.rfcEmisor).toBe('AAA010101AAA');
+    expect(result.nombreEmisor).toBe('Refacciones del Norte SA');
+  });
+
+  it('should extract fecha, subtotal, total', () => {
+    const result = parseCfdiFile(fixturePath);
+    expect(result.fecha).toBe('2026-01-15T10:30:00');
+    expect(result.subtotal).toBe(1500.0);
+    expect(result.total).toBe(1740.0);
+  });
+
+  it('should extract all conceptos', () => {
+    const result = parseCfdiFile(fixturePath);
+    expect(result.conceptos).toHaveLength(2);
+
+    expect(result.conceptos[0]).toEqual({
+      claveProdServ: '25101503',
+      noIdentificacion: 'BK-001',
+      descripcion: 'Balata ceramica delantera',
+      cantidad: 4,
+      valorUnitario: 250.0,
+      importe: 1000.0,
+    });
+  });
+
+  it('should handle single concepto (not array)', () => {
+    const singleConceptXml = `<?xml version="1.0" encoding="utf-8"?>
+    <cfdi:Comprobante xmlns:cfdi="http://www.sat.gob.mx/cfd/4"
+      xmlns:tfd="http://www.sat.gob.mx/TimbreFiscalDigital"
+      Version="4.0" Fecha="2026-02-01T08:00:00" SubTotal="100.00" Total="116.00">
+      <cfdi:Emisor Rfc="BBB020202BBB" Nombre="Proveedor Unico" />
+      <cfdi:Conceptos>
+        <cfdi:Concepto ClaveProdServ="12345678" NoIdentificacion="X-1"
+          Descripcion="Articulo unico" Cantidad="1"
+          ValorUnitario="100.00" Importe="100.00" />
+      </cfdi:Conceptos>
+      <cfdi:Complemento>
+        <tfd:TimbreFiscalDigital UUID="SINGLE-UUID-TEST" />
+      </cfdi:Complemento>
+    </cfdi:Comprobante>`;
+
+    const tmpPath = path.join(__dirname, 'fixtures', 'single-concept.xml');
+    fs.writeFileSync(tmpPath, singleConceptXml);
+
+    const result = parseCfdiFile(tmpPath);
+    expect(result.conceptos).toHaveLength(1);
+    expect(result.conceptos[0].descripcion).toBe('Articulo unico');
+
+    fs.unlinkSync(tmpPath);
+  });
+});

tests/fixtures/sample-cfdi.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<cfdi:Comprobante xmlns:cfdi="http://www.sat.gob.mx/cfd/4"
+  xmlns:tfd="http://www.sat.gob.mx/TimbreFiscalDigital"
+  Version="4.0"
+  Fecha="2026-01-15T10:30:00"
+  SubTotal="1500.00"
+  Total="1740.00">
+  <cfdi:Emisor Rfc="AAA010101AAA" Nombre="Refacciones del Norte SA" />
+  <cfdi:Conceptos>
+    <cfdi:Concepto ClaveProdServ="25101503" NoIdentificacion="BK-001"
+      Descripcion="Balata ceramica delantera" Cantidad="4"
+      ValorUnitario="250.00" Importe="1000.00" />
+    <cfdi:Concepto ClaveProdServ="25101504" NoIdentificacion="FT-200"
+      Descripcion="Filtro de aceite" Cantidad="10"
+      ValorUnitario="50.00" Importe="500.00" />
+  </cfdi:Conceptos>
+  <cfdi:Complemento>
+    <tfd:TimbreFiscalDigital UUID="6F8A29C3-1234-4567-8901-ABCDEF123456" />
+  </cfdi:Complemento>
+</cfdi:Comprobante>

tests/import-service.test.js

@@ -0,0 +1,55 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+describe('Import Service', () => {
+  let db;
+
+  beforeEach(async () => {
+    const { createDatabase } = await import('../src/services/database.js');
+    db = createDatabase(':memory:');
+  });
+
+  it('should import a CFDI XML into the database', async () => {
+    const { importXmlFile } = await import('../src/services/import-service.js');
+    const fixturePath = path.join(__dirname, 'fixtures', 'sample-cfdi.xml');
+    const result = importXmlFile(db, fixturePath);
+
+    expect(result.success).toBe(true);
+    expect(result.uuid).toBe('6F8A29C3-1234-4567-8901-ABCDEF123456');
+
+    const factura = db.prepare('SELECT * FROM facturas WHERE uuid = ?').get(result.uuid);
+    expect(factura).toBeTruthy();
+    expect(factura.nombre_emisor).toBe('Refacciones del Norte SA');
+
+    const conceptos = db.prepare('SELECT * FROM conceptos WHERE factura_id = ?').all(factura.id);
+    expect(conceptos).toHaveLength(2);
+  });
+
+  it('should skip duplicate UUIDs', async () => {
+    const { importXmlFile } = await import('../src/services/import-service.js');
+    const fixturePath = path.join(__dirname, 'fixtures', 'sample-cfdi.xml');
+    importXmlFile(db, fixturePath);
+    const result = importXmlFile(db, fixturePath);
+
+    expect(result.success).toBe(false);
+    expect(result.reason).toBe('duplicate');
+  });
+
+  it('should cross-reference intercambios from catalogo', async () => {
+    const { importXmlFile } = await import('../src/services/import-service.js');
+    db.prepare(
+      'INSERT INTO catalogo_intercambios (no_parte_proveedor, no_parte_intercambio) VALUES (?, ?)'
+    ).run('BK-001', 'INT-9999');
+
+    const fixturePath = path.join(__dirname, 'fixtures', 'sample-cfdi.xml');
+    importXmlFile(db, fixturePath);
+
+    const concepto = db.prepare(
+      "SELECT * FROM conceptos WHERE no_identificacion = 'BK-001'"
+    ).get();
+    expect(concepto.intercambio).toBe('INT-9999');
+  });
+});