<?php
// @codingStandardsIgnoreFile
/**
* Array utilities.
*
* Copyright: © 2009-2011
* {@link http://websharks-inc.com/ WebSharks, Inc.}
* (coded in the USA)
*
* Released under the terms of the GNU General Public License.
* You should have received a copy of the GNU General Public License,
* along with this software. In the main directory, see: /licensing/
* If not, see: {@link http://www.gnu.org/licenses/}.
*
* @package s2Member\Utilities
* @since 3.5
*/
if(!defined('WPINC')) // MUST have WordPress.
	exit ("Do not access this file directly.");

if (!class_exists ("c_ws_plugin__s2member_utils_arrays"))
	{
		/**
		* Array utilities.
		*
		* @package s2Member\Utilities
		* @since 3.5
		*/
		class c_ws_plugin__s2member_utils_arrays
			{
				/**
				* Extends ``array_unique()`` to support multi-dimensional arrays.
				*
				* @package s2Member\Utilities
				* @since 3.5
				*
				* @param array $array Expects an incoming array.
				* @return array Returns the ``$array`` after having reduced it to a unique set of values.
				*/
				public static function array_unique ($array = FALSE)
					{
						$array = (array)$array;

						foreach ($array as &$value)
							$value = serialize ($value);

						$array = array_unique ($array);

						foreach ($array as &$value)
							$value = unserialize ($value);

						return $array;
					}
				/**
				* Searches an array *(or even a multi-dimensional array)* using a regular expression match against array values.
				*
				* @package s2Member\Utilities
				* @since 3.5
				*
				* @param string $regex A regular expression to look for inside the array.
				* @return bool True if the regular expression matched at least one value in the array, else false.
				*/
				public static function regex_in_array($regex = FALSE, $array = FALSE)
					{
						if (is_string ($regex) && strlen ($regex) && is_array($array))
							{
								foreach ($array as $value)
									{
										if (is_array($value) /* Recursive function call? */)
											{
												if (c_ws_plugin__s2member_utils_arrays::regex_in_array($regex, $value))
													return true;
											}
										else if (is_string ($value) /* Must be a string. */)
											{
												if (@preg_match ($regex, $value))
													return true;
											}
									}
								return false;
							}
						else // False.
							return false;
					}
				/**
				* Searches an array *(or even a multi-dimensional array)* of regular expressions, to match against a string value.
				*
				* @package s2Member\Utilities
				* @since 3.5
				*
				* @param string $string A string to test against.
				* @param array $array An array of regex patterns to match against ``$string``.
				* @return bool True if at least one regular expression in the ``$array`` matched ``$string``, else false.
				*/
				public static function in_regex_array($string = FALSE, $array = FALSE)
					{
						if (is_string ($string) && strlen ($string) && is_array($array))
							{
								foreach ($array as $value)
									{
										if (is_array($value) /* Recursive function call. */)
											{
												if (c_ws_plugin__s2member_utils_arrays::in_regex_array($string, $value))
													return true;
											}
										else if (is_string ($value) /* Must be a string. */)
											{
												if (@preg_match ($value, $string))
													return true;
											}
									}
								return false;
							}
						else // False.
							return false;
					}
				/**
				* Removes all null values from an array *(or even a multi-dimensional array)*.
				*
				* @package s2Member\Utilities
				* @since 111101
				*
				* @param array $array An input array.
				* @return array Returns the ``$array`` after having reduced its set of values.
				*/
				public static function remove_nulls ($array = FALSE)
					{
						$array = (array)$array;

						foreach ($array as $key => &$value)
							{
								if (is_array($value) /* Recursive function call here. */)
									$value = c_ws_plugin__s2member_utils_arrays::remove_nulls ($value);

								else if (is_null /* Is it null? */ ($value))
									unset($array[$key]);
							}
						return $array;
					}
				/**
				* Removes all 0-byte strings from an array *(or even a multi-dimensional array)*.
				*
				* @package s2Member\Utilities
				* @since 111216
				*
				* @param array $array An input array.
				* @return array Returns the ``$array`` after having reduced its set of values.
				*/
				public static function remove_0b_strings ($array = FALSE)
					{
						$array = (array)$array;

						foreach ($array as $key => &$value)
							{
								if (is_array($value) /* Recursive function call here. */)
									$value = c_ws_plugin__s2member_utils_arrays::remove_0b_strings ($value);

								else if (is_string ($value) && !strlen ($value))
									unset($array[$key]);
							}
						return $array;
					}
				/**
				* Sets specified array elements to an empty string when they are not set according to ``isset()`` (missing or NULL).
				*
				* @package s2Member\Utilities
				* @since 260814
				*
				* @param array $array An input array.
				* @param array $keys Array keys whose unset elements should be set.
				* @return array Returns the ``$array`` after setting unset elements to empty strings.
				*/
				public static function set_unset_elements ($array = FALSE, $keys = FALSE)
					{
						$array = (array)$array;
						$keys = (array)$keys;

						//260814 isset() treats both missing keys and null values as unset; initialize either case to an empty string.
						foreach ($keys as $key)
							if (!isset($array[$key]))
								$array[$key] = '';

						return $array;
					}
				/**
				* Forces string values on each array value *(also supports multi-dimensional arrays)*.
				*
				* @package s2Member\Utilities
				* @since 111101
				*
				* @param array $array An input array.
				* @return array Returns the ``$array`` after having forced it to set of string values.
				*/
				public static function force_strings ($array = FALSE)
					{
						$array = (array)$array;

						foreach ($array as &$value)
							{
								if (is_array($value) /* Recursive function call here. */)
									$value = c_ws_plugin__s2member_utils_arrays::force_strings ($value);

								else if (!is_string ($value) /* String? */)
									$value = (string)$value;
							}
						return $array;
					}
				/**
				* Forces integer values on each array value *(also supports multi-dimensional arrays)*.
				*
				* @package s2Member\Utilities
				* @since 111101
				*
				* @param array $array An input array.
				* @return array Returns the ``$array`` after having forced it to set of integer values.
				*/
				public static function force_integers ($array = array())
					{
						$array = (array)$array;

						foreach ($array as &$value)
							{
								if (is_array($value) /* Recursive function call here. */)
									$value = c_ws_plugin__s2member_utils_arrays::force_integers ($value);

								else if (!is_integer ($value) /* Integer? */)
									$value = (int)$value;
							}
						return $array;
					}
				/**
				* Sorts arrays *(also supports multi-dimensional arrays)* by key, low to high.
				*
				* @package s2Member\Utilities
				* @since 111205
				*
				* @param array $array An input array.
				* @param int $flags Optional. Can be used to modify the sorting behavior.
				* 	See: {@link http://www.php.net/manual/en/function.ksort.php}
				* @return Unlike PHP's ``ksort()``, this function returns the array, and does NOT work on a reference.
				*/
				public static function ksort_deep ($array = FALSE, $flags = SORT_REGULAR)
					{
						$array = (array)$array;
						ksort /* Sort by key. */ ($array, $flags);

						foreach ($array as &$value)
							if (is_array($value) /* Recursive function call here. */)
								$value = c_ws_plugin__s2member_utils_arrays::ksort_deep ($value, $flags);

						return /* Now return the array. */ $array;
					}

				/**
				 * Safely unserializes a value when appropriate.
				 *
				 * @package s2Member\Utilities
				 * @since 250801
				 * @since 260808 Added additional validation before unserializing.
				 * 
				 * @param mixed $value The value to be unserialized.
				 * @return mixed The unserialized value, or original if not serialized or blocked.
				 */
				public static function maybe_unserialize($value) {
					if (!is_string($value) || !is_serialized($value)) {
						return $value;
					}

					$value = trim($value);

					//260808 Reject disallowed serialization types without matching harmless text inside serialized strings.
					if (self::serialized_contains_disallowed_type($value)) {
						do_action('ws_plugin__s2member_security_object_detected', $value);
						return null;
					}

					if (version_compare(PHP_VERSION, '7.0.0', '>=')) {
						return @unserialize($value, ['allowed_classes' => false]);
					}

					return @unserialize($value);
				}

				/**
				 * Checks serialized data for disallowed serialization types.
				 *
				 * Serialized string payloads are skipped so object-like text inside a
				 * normal string does not produce a false positive.
				 *
				 * @package s2Member\Utilities
				 * @since 260808
				 *
				 * @param string $value Serialized value to inspect.
				 * @return bool True if a disallowed serialization type is present.
				 */
				private static function serialized_contains_disallowed_type($value) {
					$length = strlen($value);

					for ($offset = 0; $offset < $length; ++$offset) {
						$token = $value[$offset];

						//260808 Skip complete serialized strings so harmless text such as "PROMO:" is not mistaken for an object token.
						if ($token === 's' && isset($value[$offset + 1]) && $value[$offset + 1] === ':') {
							if (!preg_match('/\Gs:([0-9]+):"/', $value, $match, 0, $offset)) {
								continue;
							}

							$string_length = (int)$match[1];
							$string_start  = $offset + strlen($match[0]);
							$string_end    = $string_start + $string_length;

							if ($string_end + 1 >= $length || substr($value, $string_end, 2) !== '";') {
								return true;
							}

							$offset = $string_end + 1;
							continue;
						}

						//260808 O=object, C=Serializable object, E=enum object, S=noncanonical string, R/r=references that can create cyclic structures.
						if (($token === 'O' || $token === 'C' || $token === 'E' || $token === 'S' || $token === 'R' || $token === 'r')
							&& isset($value[$offset + 1]) && $value[$offset + 1] === ':') {
							return true;
						}
					}

					return false;
				}
			}
	}