funciones_servicios_dart_flutter_mobile #

A comprehensive calculation engine for transaction valuation and tax calculations in Flutter mobile applications. This package handles critical business functions including price calculations, volume conversions, tax calculations (IVA, internal taxes), and fiscal compliance for invoicing systems.

Features #

• Price Calculations: Calculate unit prices based on volume units from price lists
• Taxable Base Calculations: Compute taxable base amounts for transactions
• Tax Calculations: Handle IVA, internal taxes, and other fiscal requirements
• Volume Conversions: Support for sales, production, and stock volume calculations
• Multi-currency Support: Handle transactions with multiple currencies via exchange rates
• Hash-based Optimization: SHA-256 hashing for change detection to avoid redundant calculations
• Schema-driven Architecture: Dynamic field mapping via keyDesarrollo for flexible configuration

Installation #

Add this package to your pubspec.yaml:

dependencies:
  funciones_servicios_dart_flutter_mobile: ^1.0.0

Then run:

flutter pub get

Usage #

Basic Setup #

import 'package:funciones_servicios_dart_flutter_mobile/funciones_servicios_dart_flutter_mobile.dart';

// Initialize the service (singleton pattern)
final funcionesServicios = FuncionesServicios(apiRest: apiRest);

// Initialize functions with schema
await funcionesServicios.initFunciones(
  coleccion: 'transaccion',
  funciones: [
    Funciones.calcularPrecioUnitarioxUnidadVolumen.name,
    Funciones.calcularBaseImponible.name,
    Funciones.calcularImpuestos.name,
  ],
  esquema: mySchema,
);

Available Functions #

Recommended Execution Order #

For invoicing transactions, execute functions in this order:

1. calcularPrecioUnitarioxUnidadVolumen
2. calcularBaseImponible
3. calcularImpuestos

Executing Functions #

// Update specific item
final result = await funcionesServicios.ejecutaFuncionActualizarItems(
  coleccion: 'transaccion',
  funciones: funciones,
  data: transactionData,
  accion: AccionFunServicio.actualizar,
  idItemData: itemId,
);

// Recalculate entire transaction
final result = await funcionesServicios.ejecutaFuncionesEnTodoElRegistro(
  coleccion: 'transaccion',
  funciones: funciones,
  data: transactionData,
);

// Recalculate totals only (for save operations)
final result = await funcionesServicios.ejecutaFuncionesGuardar(
  coleccion: 'transaccion',
  funciones: funciones,
  data: transactionData,
);

Hash-based Change Detection #

Before editing, establish a hash to track changes:

await funcionesServicios.estableceHash(
  coleccion: 'transaccion',
  funciones: funciones,
  data: transactionData,
  accion: AccionFunServicio.modificar,
  idItem: itemId,
);

Schema Configuration #

The package requires proper schema configuration with keyDesarrollo mappings. See the package documentation for detailed schema setup instructions.

Platform Support #

Dependencies #

This package depends on:

• api_rest_flutter_mobile - REST API integration
• flutter_models_provider - Data models and ObjectBox integration
• flutter_utils_providers - Utility functions for schema navigation
• crypto - SHA-256 hashing for change detection
• uuid - UUID generation

License #

This project is licensed under the MIT License - see the LICENSE file for details.