<?php
/**
 * Joomla! Content Management System
 *
 * @copyright  (C) 2019 Open Source Matters, Inc. <https://www.joomla.org>
 * @license    GNU General Public License version 2 or later; see LICENSE.txt
 */

namespace Joomla\CMS\Form\Filter;

\defined('JPATH_PLATFORM') or die;

use Joomla\CMS\Form\Form;
use Joomla\CMS\Form\FormFilterInterface;
use Joomla\Registry\Registry;

/**
 * Form Filter class for phone numbers
 *
 * @since  4.0.0
 */
class TelFilter implements FormFilterInterface
{
	/**
	 * Method to filter a field value.
	 *
	 * @param   \SimpleXMLElement  $element  The SimpleXMLElement object representing the `<field>` tag for the form field object.
	 * @param   mixed              $value    The form field value to validate.
	 * @param   string             $group    The field name group control value. This acts as an array container for the field.
	 *                                       For example if the field has name="foo" and the group value is set to "bar" then the
	 *                                       full field name would end up being "bar[foo]".
	 * @param   Registry           $input    An optional Registry object with the entire data set to validate against the entire form.
	 * @param   Form               $form     The form object for which the field is being tested.
	 *
	 * @return  mixed   The filtered value.
	 *
	 * @since   4.0.0
	 */
	public function filter(\SimpleXMLElement $element, $value, $group = null, Registry $input = null, Form $form = null)
	{
		$value = trim($value);

		// Does it match the NANP pattern?
		if (preg_match('/^(?:\+?1[-. ]?)?\(?([2-9][0-8][0-9])\)?[-. ]?([2-9][0-9]{2})[-. ]?([0-9]{4})$/', $value) == 1)
		{
			$number = (string) preg_replace('/[^\d]/', '', $value);

			if (substr($number, 0, 1) === '1')
			{
				$number = substr($number, 1);
			}

			if (substr($number, 0, 2) === '+1')
			{
				$number = substr($number, 2);
			}

			$result = '1.' . $number;
		}

		// If not, does it match ITU-T?
		elseif (preg_match('/^\+(?:[0-9] ?){6,14}[0-9]$/', $value) == 1)
		{
			$countrycode = substr($value, 0, strpos($value, ' '));
			$countrycode = (string) preg_replace('/[^\d]/', '', $countrycode);
			$number = strstr($value, ' ');
			$number = (string) preg_replace('/[^\d]/', '', $number);
			$result = $countrycode . '.' . $number;
		}

		// If not, does it match EPP?
		elseif (preg_match('/^\+[0-9]{1,3}\.[0-9]{4,14}(?:x.+)?$/', $value) == 1)
		{
			if (strstr($value, 'x'))
			{
				$xpos = strpos($value, 'x');
				$value = substr($value, 0, $xpos);
			}

			$result = str_replace('+', '', $value);
		}

		// Maybe it is already ccc.nnnnnnn?
		elseif (preg_match('/[0-9]{1,3}\.[0-9]{4,14}$/', $value) == 1)
		{
			$result = $value;
		}

		// If not, can we make it a string of digits?
		else
		{
			$value = (string) preg_replace('/[^\d]/', '', $value);

			if ($value != null && \strlen($value) <= 15)
			{
				$length = \strlen($value);

				// If it is fewer than 13 digits assume it is a local number
				if ($length <= 12)
				{
					$result = '.' . $value;
				}
				else
				{
					// If it has 13 or more digits let's make a country code.
					$cclen = $length - 12;
					$result = substr($value, 0, $cclen) . '.' . substr($value, $cclen);
				}
			}

			// If not let's not save anything.
			else
			{
				$result = '';
			}
		}

		return $result;
	}
}
