CurpValidator.php

<?php
/**
 * @author     Carlos Ramos <carlos@ktaris.com>
 * @copyright  2015 Carlos Ramos.
 * @license    http://www.opensource.org/licenses/mit-license.php  MIT License
 * @version    0.0.1
 * @link       https://github.com/ktaris/yii2-mexvalidators
 */

namespace jcabanillas\mexvalidators;

use yii\validators\Validator;

/**
 * Valida que la cadena sea una CURP válida según las leyes mexicanas.
 *
 * Validates that the string is a valid CURP according to Mexican law.
 */
class CurpValidator extends Validator
{
    /**
     * Determina si se convierte el campo a mayúsculas automáticamente.
     * @var boolean determines if the field is automatically converted to uppercase.
     */
    public $toUpper = true;

    /**
     * @inheritdoc
     */
    public function init()
    {
        if ($this->message === null) {
            $this->message = \Yii::t('yii', '{attribute} must be a string.');
        }
    }

    /**
     * @inheritdoc
     */
    public function validateAttribute($model, $attribute)
    {
        //Uppercase the value (all RFC must be uppercase).
        if ($this->toUpper === true) {
            $model->{$attribute} = strtoupper($model->{$attribute});
        }
        //Proceed with value validation.
        $value = $model->{$attribute};
        $errorMessage = $this->validateValue($value);
        if ($errorMessage) {
            $this->addError($model, $attribute, $this->message);
        }
    }

    /**
     * @inheritdoc
     */
    protected function validateValue($value)
    {
        //Check the attribute is a string.
        if (!is_string($value)) {
            return $this->message;
        }
        //Check against the pattern.
        $pattern = '/^[A-Z][A,E,I,O,U,X][A-Z]{2}[0-9]{2}[0-1][0-9][0-3][0-9][M,H][A-Z]{2}[B,C,D,F,G,H,J,K,L,M,N,Ñ,P,Q,R,S,T,V,W,X,Y,Z]{3}[0-9,A-Z][0-9]$/';
        $result = preg_match($pattern, $value);
        if ($result !== 1) { //there was no match.
            $this->message = \Yii::t('yii', 'The format of {attribute} is invalid.');
            return $this->message;
        }
        //Return false (meaning no error occurred).
        return false;
    }
}