<?php
/**
 * Class: Validator Helper.
 *
 * Helper class used for validating data.
 *
 * @package wsal
 */

declare(strict_types=1);

namespace WSAL\Helpers;

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( '\WSAL\Helpers\Validator' ) ) {
	/**
	 * Responsible for data validation
	 */
	class Validator {

		/**
		 * Validates mirror tags against rule sets
		 * Note: no short-returns here as this could be used to collect all the problems for give tag
		 *
		 * @param string $string - The string to validate.
		 *
		 * @return boolean - true - tag is valid, false - tag is not valid.
		 *
		 * @since 4.4.2.1
		 */
		public static function validate_mirror_tag( string $string ): bool {

			$valid = true;

			if ( ! self::starts_alpha_numeric( $string ) ) {
				$valid = false;
			}

			if ( ! self::is_string_less_or_equal( $string, 64 ) ) {
				$valid = false;
			}

			if ( ! self::is_string_contains_only( $string ) ) {
				$valid = false;
			}

			return $valid;
		}

		/**
		 * Checks if given string starts with a letter or number.
		 *
		 * @param string $string - The string to check.
		 *
		 * @return boolean
		 *
		 * @since 4.4.2.1
		 */
		private static function starts_alpha_numeric( string $string ): bool {
			if ( preg_match( '/^[a-zA-Z0-9]/', $string ) ) {
				return true;
			}

			return false;
		}

		/**
		 * Checks if string has less or equal number of characters.
		 *
		 * @param string  $string - The string to check.
		 * @param integer $size - The size of the string to check for.
		 *
		 * @return boolean
		 *
		 * @since 4.4.2.1
		 */
		private static function is_string_less_or_equal( string $string, int $size ): bool {
			if ( strlen( $string ) <= $size ) {
				return true;
			}

			return false;
		}

		/**
		 * Check if string contains only specific characters
		 *
		 * @param string $string - The string to check.
		 *
		 * @return boolean
		 *
		 * @since 4.4.2.1
		 */
		private static function is_string_contains_only( string $string ): bool {
			if ( preg_match( '/[a-z\d_-]*/i', $string ) ) {
				return true;
			}
			return false;
		}

		/**
		 * Validate IP address.
		 *
		 * @param string $ip - IP address.
		 *
		 * @return string|bool
		 */
		public static function validate_ip( $ip ) {
			$opts = FILTER_FLAG_IPV4 | FILTER_FLAG_IPV6;

			if ( \WSAL\Helpers\Settings_Helper::get_boolean_option_value( 'filter-internal-ip', false ) ) {
				$opts = $opts | FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE;
			}

			$filtered_ip = filter_var( $ip, FILTER_VALIDATE_IP, $opts );

			if ( ! $filtered_ip || empty( $filtered_ip ) ) {
				// Regex IPV4.
				if ( preg_match( '/^(([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){3}([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$/', $ip ) ) {
					return $ip;
				} elseif ( preg_match( '/^\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))(%.+)?\s*$/', $ip ) ) {
					// Regex IPV6.
					return $ip;
				}

				return false;
			} else {
				return $filtered_ip;
			}
		}

		/**
		 * Simple check for validating a URL, it must start with http:// or https://.
		 * and pass FILTER_VALIDATE_URL validation.
		 *
		 * @param string $url to check.
		 *
		 * @return bool
		 *
		 * @since 4.6.0
		 */
		public static function is_valid_url( $url ) {
			// Must start with http:// or https://.
			if ( 0 !== strpos( $url, 'http://' ) && 0 !== strpos( $url, 'https://' ) ) {
				return false;
			}

			// Must pass validation.
			if ( ! filter_var( $url, FILTER_VALIDATE_URL ) ) {
				return false;
			}

			return true;
		}

		/**
		 * Check if the float is IPv4 instead.
		 *
		 * @param float $ip_address - Number to check.
		 *
		 * @return bool result validation
		 *
		 * @since 4.6.0
		 */
		public static function is_ip_address( $ip_address ) {
			return filter_var( $ip_address, FILTER_VALIDATE_IP ) !== false;
		}
	}
}