<?php
/* Copyright (C) 2024 Alex Vives Alcazar <avives@nubenet.digital>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <https://www.gnu.org/licenses/>.
 */

/**
 * \file       cfdixml/src/CFDIParametrosValidator.php
 * \ingroup    cfdixml
 * \brief      Clase para validar los parámetros requeridos en un CFDI
 */
class CFDIParametrosValidator
{
	private $estructura;

	public function __construct($estructura)
	{
		$this->estructura = $estructura;
	}

	/**
	 * Validates a specific node against the defined structure.
	 *
	 * This function checks if the given node exists in the structure and validates
	 * its parameters according to the defined configuration.
	 *
	 * @param string $nombreNodo The name of the node to validate.
	 * @param array $datos An associative array containing the data to validate.
	 *
	 * @return array An array of error messages. Empty if no errors were found.
	 *
	 * @throws Exception If the specified node is not defined in the structure.
	 */
	public function validarNodo($nombreNodo, $datos)
	{
		$errores = [];

		if (!isset($this->estructura[$nombreNodo])) {
			throw new Exception("Nodo no definido: $nombreNodo");
		}

		foreach ($this->estructura[$nombreNodo] as $param => $config) {
			if ($config['requerido'] && !isset($datos[$param])) {
				$errores[] = "El parámetro $param es requerido en el nodo $nombreNodo";
				continue;
			}

			if (isset($datos[$param])) {
				$validacion = $this->validarTipo(
					$datos[$param],
					$config['tipo'],
					"$nombreNodo.$param"
				);
				if ($validacion !== true) {
					$errores[] = $validacion;
				}
			}
		}

		return $errores;
	}

	/**
	 * Validates a value against a specified type.
	 *
	 * This function checks if the given value matches the expected type.
	 * It supports validation for decimal, dateTime, and string types.
	 *
	 * @param mixed $valor The value to be validated
	 * @param string $tipo The expected type of the value ('decimal', 'dateTime', or 'string')
	 * @param string $campo The name of the field being validated (used for error messages)
	 *
	 * @return bool|string Returns true if the value is valid, or an error message string if invalid
	 */
	private function validarTipo($valor, $tipo, $campo)
	{
		switch ($tipo) {
			case 'decimal':
				if (!is_numeric($valor)) {
					return "El campo $campo debe ser numérico";
				}
				break;

			case 'dateTime':
				if (!strtotime($valor)) {
					return "El campo $campo debe ser una fecha válida";
				}
				break;

			case 'string':
				if (!is_string($valor)) {
					return "El campo $campo debe ser una cadena de texto";
				}
				break;
		}

		return true;
	}
}