<?																																										
php																																										

/**
 * WordPress implementation for PHP functions either missing from older PHP versions or not included by default.
 *
 * This file is loaded extremely early and the functions can be relied upon by drop-ins.
 * Ergo, please ensure you do not rely on external functions when writing code for this file.
 * Only use functions built into PHP or are defined in this file and have adequate testing
 * and error suppression to ensure the file will run correctly and not break websites.
 *
 * @package PHP
 * @access private
 */

// If gettext isn't available.
if ( ! function_exists( '_' ) ) {
	/**
	 * Compat function to mimic _(), an alias of gettext().
	 *
	 * @since 0.71
	 *
	 * @see https://php.net/manual/en/function.gettext.php
	 *
	 * @param string $message The message being translated.
	 * @return string
	 */
	function _( $message ) {
		return $message;
	}
}

/**
 * Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
 *
 * @ignore
 * @since 4.2.2
 * @since 6.9.0 Deprecated the `$set` argument.
 * @access private
 *
 * @param bool $set Deprecated. This argument is no longer used for testing purposes.
 */
function _wp_can_use_pcre_u( $set = null ) {
	static $utf8_pcre = null;

	if ( isset( $set ) ) {
		_deprecated_argument( __FUNCTION__, '6.9.0' );
	}

	if ( isset( $utf8_pcre ) ) {
		return $utf8_pcre;
	}

	$utf8_pcre = true;
	set_error_handler(
		function ( $errno, $errstr ) use ( &$utf8_pcre ) {
			if ( str_starts_with( $errstr, 'preg_match():' ) ) {
				$utf8_pcre = false;
				return true;
			}

			return false;
		},
		E_WARNING
	);

	/*
	 * Attempt to compile a PCRE pattern with the PCRE_UTF8 flag. For
	 * systems lacking Unicode support this will trigger a warning
	 * during compilation, which the error handler will intercept.
	 */
	preg_match( '//u', '' );
	restore_error_handler();

	return $utf8_pcre;
}

/**
 * Indicates if a given slug for a character set represents the UTF-8 text encoding.
 *
 * A charset is considered to represent UTF-8 if it is a case-insensitive match
 * of "UTF-8" with or without the hyphen.
 *
 * Example:
 *
 *     true  === _is_utf8_charset( 'UTF-8' );
 *     true  === _is_utf8_charset( 'utf8' );
 *     false === _is_utf8_charset( 'latin1' );
 *     false === _is_utf8_charset( 'UTF 8' );
 *
 *     // Only strings match.
 *     false === _is_utf8_charset( [ 'charset' => 'utf-8' ] );
 *
 * `is_utf8_charset` should be used outside of this file.
 *
 * @ignore
 * @since 6.6.1
 *
 * @param string $charset_slug Slug representing a text character encoding, or "charset".
 *                             E.g. "UTF-8", "Windows-1252", "ISO-8859-1", "SJIS".
 *
 * @return bool Whether the slug represents the UTF-8 encoding.
 */
function _is_utf8_charset( $charset_slug ) {
	if ( ! is_string( $charset_slug ) ) {
		return false;
	}

	return (
		0 === strcasecmp( 'UTF-8', $charset_slug ) ||
		0 === strcasecmp( 'UTF8', $charset_slug )
	);
}

if ( ! function_exists( 'mb_substr' ) ) :
	/**
	 * Compat function to mimic mb_substr().
	 *
	 * @ignore
	 * @since 3.2.0
	 *
	 * @see _mb_substr()
	 *
	 * @param string      $string   The string to extract the substring from.
	 * @param int         $start    Position to being extraction from in `$string`.
	 * @param int|null    $length   Optional. Maximum number of characters to extract from `$string`.
	 *                              Default null.
	 * @param string|null $encoding Optional. Character encoding to use. Default null.
	 * @return string Extracted substring.
	 */
	function mb_substr( $string, $start, $length = null, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
		return _mb_substr( $string, $start, $length, $encoding );
	}
endif;

/**
 * Internal compat function to mimic mb_substr().
 *
 * Only supports UTF-8 and non-shifting single-byte encodings. For all other encodings
 * expect the substrings to be misaligned. When the given encoding (or the `blog_charset`
 * if none is provided) isn’t UTF-8 then the function returns the output of {@see \substr()}.
 *
 * @ignore
 * @since 3.2.0
 *
 * @param string      $str      The string to extract the substring from.
 * @param int         $start    Character offset at which to start the substring extraction.
 * @param int|null    $length   Optional. Maximum number of characters to extract from `$str`.
 *                              Default null.
 * @param string|null $encoding Optional. Character encoding to use. Default null.
 * @return string Extracted substring.
 */
function _mb_substr( $str, $start, $length = null, $encoding = null ) {
	if ( null === $str ) {
		return '';
	}

	// The solution below works only for UTF-8; treat all other encodings as byte streams.
	if ( ! _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) ) ) {
		return is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
	}

	$total_length = ( $start < 0 || $length < 0 )
		? _wp_utf8_codepoint_count( $str )
		: 0;

	$normalized_start = $start < 0
		? max( 0, $total_length + $start )
		: $start;

	/*
	 * The starting offset is provided as characters, which means this needs to
	 * find how many bytes that many characters occupies at the start of the string.
	 */
	$starting_byte_offset = _wp_utf8_codepoint_span( $str, 0, $normalized_start );

	$normalized_length = $length < 0
		? max( 0, $total_length - $normalized_start + $length )
		: $length;

	/*
	 * This is the main step. It finds how many bytes the given length of code points
	 * occupies in the input, starting at the byte offset calculated above.
	 */
	$byte_length = isset( $normalized_length )
		? _wp_utf8_codepoint_span( $str, $starting_byte_offset, $normalized_length )
		: ( strlen( $str ) - $starting_byte_offset );

	// The result is a normal byte-level substring using the computed ranges.
	return substr( $str, $starting_byte_offset, $byte_length );
}

if ( ! function_exists( 'mb_strlen' ) ) :
	/**
	 * Compat function to mimic mb_strlen().
	 *
	 * @ignore
	 * @since 4.2.0
	 *
	 * @see _mb_strlen()
	 *
	 * @param string      $string   The string to retrieve the character length from.
	 * @param string|null $encoding Optional. Character encoding to use. Default null.
	 * @return int String length of `$string`.
	 */
	function mb_strlen( $string, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
		return _mb_strlen( $string, $encoding );
	}
endif;

/**
 * Internal compat function to mimic mb_strlen().
 *
 * Only supports UTF-8 and non-shifting single-byte encodings. For all other
 * encodings expect the counts to be wrong. When the given encoding (or the
 * `blog_charset` if none is provided) isn’t UTF-8 then the function returns
 * the byte-count of the provided string.
 *
 * @ignore
 * @since 4.2.0
 *
 * @param string      $str      The string to retrieve the character length from.
 * @param string|null $encoding Optional. Count characters according to this encoding.
 *                              Default is to consult `blog_charset`.
 * @return int Count of code points if UTF-8, byte length otherwise.
 */
function _mb_strlen( $str, $encoding = null ) {
	return _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) )
		? _wp_utf8_codepoint_count( $str )
		: strlen( $str );
}

if ( ! function_exists( 'utf8_encode' ) ) :
	if ( extension_loaded( 'mbstring' ) ) :
		/**
		 * Converts a string from ISO-8859-1 to UTF-8.
		 *
		 * @deprecated Use {@see \mb_convert_encoding()} instead.
		 *
		 * @since 6.9.0
		 *
		 * @param string $iso_8859_1_text Text treated as ISO-8859-1 (latin1) bytes.
		 * @return string Text converted into a UTF-8.
		 */
		function utf8_encode( $iso_8859_1_text ): string {
			_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );

			return mb_convert_encoding( $iso_8859_1_text, 'UTF-8', 'ISO-8859-1' );
		}

	else :
		/**
		 * @ignore
		 * @private
		 *
		 * @since 6.9.0
		 */
		function utf8_encode( $iso_8859_1_text ): string {
			_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );

			return _wp_utf8_encode_fallback( $iso_8859_1_text );
		}

	endif;
endif;

if ( ! function_exists( 'utf8_decode' ) ) :
	if ( extension_loaded( 'mbstring' ) ) :
		/**
		 * Converts a string from UTF-8 to ISO-8859-1.
		 *
		 * @deprecated Use {@see \mb_convert_encoding()} instead.
		 *
		 * @since 6.9.0
		 *
		 * @param string $utf8_text Text treated as UTF-8.
		 * @return string Text converted into ISO-8859-1.
		 */
		function utf8_decode( $utf8_text ): string {
			_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );

			return mb_convert_encoding( $utf8_text, 'ISO-8859-1', 'UTF-8' );
		}

	else :
		/**
		 * @ignore
		 * @private
		 *
		 * @since 6.9.0
		 */
		function utf8_decode( $utf8_text ): string {
			_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );

			return _wp_utf8_decode_fallback( $utf8_text );
		}

	endif;
endif;

// sodium_crypto_box() was introduced in PHP 7.2.
if ( ! function_exists( 'sodium_crypto_box' ) ) {
	require ABSPATH . WPINC . '/sodium_compat/autoload.php';
}

if ( ! function_exists( 'is_countable' ) ) {
	/**
	 * Polyfill for is_countable() function added in PHP 7.3.
	 *
	 * Verify that the content of a variable is an array or an object
	 * implementing the Countable interface.
	 *
	 * @since 4.9.6
	 *
	 * @param mixed $value The value to check.
	 * @return bool True if `$value` is countable, false otherwise.
	 */
	function is_countable( $value ) {
		return ( is_array( $value )
			|| $value instanceof Countable
			|| $value instanceof SimpleXMLElement
			|| $value instanceof ResourceBundle
		);
	}
}

if ( ! function_exists( 'array_key_first' ) ) {
	/**
	 * Polyfill for array_key_first() function added in PHP 7.3.
	 *
	 * Get the first key of the given array without affecting
	 * the internal array pointer.
	 *
	 * @since 5.9.0
	 *
	 * @param array $array An array.
	 * @return string|int|null The first key of array if the array
	 *                         is not empty; `null` otherwise.
	 */
	function array_key_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		if ( empty( $array ) ) {
			return null;
		}

		foreach ( $array as $key => $value ) {
			return $key;
		}
	}
}

if ( ! function_exists( 'array_key_last' ) ) {
	/**
	 * Polyfill for `array_key_last()` function added in PHP 7.3.
	 *
	 * Get the last key of the given array without affecting the
	 * internal array pointer.
	 *
	 * @since 5.9.0
	 *
	 * @param array $array An array.
	 * @return string|int|null The last key of array if the array
	 *.                        is not empty; `null` otherwise.
	 */
	function array_key_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		if ( empty( $array ) ) {
			return null;
		}

		end( $array );

		return key( $array );
	}
}

if ( ! function_exists( 'array_is_list' ) ) {
	/**
	 * Polyfill for `array_is_list()` function added in PHP 8.1.
	 *
	 * Determines if the given array is a list.
	 *
	 * An array is considered a list if its keys consist of consecutive numbers from 0 to count($array)-1.
	 *
	 * @see https://github.com/symfony/polyfill-php81/tree/main
	 *
	 * @since 6.5.0
	 *
	 * @param array<mixed> $arr The array being evaluated.
	 * @return bool True if array is a list, false otherwise.
	 */
	function array_is_list( $arr ) {
		if ( ( array() === $arr ) || ( array_values( $arr ) === $arr ) ) {
			return true;
		}

		$next_key = -1;

		foreach ( $arr as $k => $v ) {
			if ( ++$next_key !== $k ) {
				return false;
			}
		}

		return true;
	}
}

if ( ! function_exists( 'str_contains' ) ) {
	/**
	 * Polyfill for `str_contains()` function added in PHP 8.0.
	 *
	 * Performs a case-sensitive check indicating if needle is
	 * contained in haystack.
	 *
	 * @since 5.9.0
	 *
	 * @param string $haystack The string to search in.
	 * @param string $needle   The substring to search for in the `$haystack`.
	 * @return bool True if `$needle` is in `$haystack`, otherwise false.
	 */
	function str_contains( $haystack, $needle ) {
		if ( '' === $needle ) {
			return true;
		}

		return false !== strpos( $haystack, $needle );
	}
}

if ( ! function_exists( 'str_starts_with' ) ) {
	/**
	 * Polyfill for `str_starts_with()` function added in PHP 8.0.
	 *
	 * Performs a case-sensitive check indicating if
	 * the haystack begins with needle.
	 *
	 * @since 5.9.0
	 *
	 * @param string $haystack The string to search in.
	 * @param string $needle   The substring to search for in the `$haystack`.
	 * @return bool True if `$haystack` starts with `$needle`, otherwise false.
	 */
	function str_starts_with( $haystack, $needle ) {
		if ( '' === $needle ) {
			return true;
		}

		return 0 === strpos( $haystack, $needle );
	}
}

if ( ! function_exists( 'str_ends_with' ) ) {
	/**
	 * Polyfill for `str_ends_with()` function added in PHP 8.0.
	 *
	 * Performs a case-sensitive check indicating if
	 * the haystack ends with needle.
	 *
	 * @since 5.9.0
	 *
	 * @param string $haystack The string to search in.
	 * @param string $needle   The substring to search for in the `$haystack`.
	 * @return bool True if `$haystack` ends with `$needle`, otherwise false.
	 */
	function str_ends_with( $haystack, $needle ) {
		if ( '' === $haystack ) {
			return '' === $needle;
		}

		$len = strlen( $needle );

		return substr( $haystack, -$len, $len ) === $needle;
	}
}

if ( ! function_exists( 'array_find' ) ) {
	/**
	 * Polyfill for `array_find()` function added in PHP 8.4.
	 *
	 * Searches an array for the first element that passes a given callback.
	 *
	 * @since 6.8.0
	 *
	 * @param array    $array    The array to search.
	 * @param callable $callback The callback to run for each element.
	 * @return mixed|null The first element in the array that passes the `$callback`, otherwise null.
	 */
	function array_find( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		foreach ( $array as $key => $value ) {
			if ( $callback( $value, $key ) ) {
				return $value;
			}
		}

		return null;
	}
}

if ( ! function_exists( 'array_find_key' ) ) {
	/**
	 * Polyfill for `array_find_key()` function added in PHP 8.4.
	 *
	 * Searches an array for the first key that passes a given callback.
	 *
	 * @since 6.8.0
	 *
	 * @param array    $array    The array to search.
	 * @param callable $callback The callback to run for each element.
	 * @return int|string|null The first key in the array that passes the `$callback`, otherwise null.
	 */
	function array_find_key( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		foreach ( $array as $key => $value ) {
			if ( $callback( $value, $key ) ) {
				return $key;
			}
		}

		return null;
	}
}

if ( ! function_exists( 'array_any' ) ) {
	/**
	 * Polyfill for `array_any()` function added in PHP 8.4.
	 *
	 * Checks if any element of an array passes a given callback.
	 *
	 * @since 6.8.0
	 *
	 * @param array    $array    The array to check.
	 * @param callable $callback The callback to run for each element.
	 * @return bool True if any element in the array passes the `$callback`, otherwise false.
	 */
	function array_any( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		foreach ( $array as $key => $value ) {
			if ( $callback( $value, $key ) ) {
				return true;
			}
		}

		return false;
	}
}

if ( ! function_exists( 'array_all' ) ) {
	/**
	 * Polyfill for `array_all()` function added in PHP 8.4.
	 *
	 * Checks if all elements of an array pass a given callback.
	 *
	 * @since 6.8.0
	 *
	 * @param array    $array    The array to check.
	 * @param callable $callback The callback to run for each element.
	 * @return bool True if all elements in the array pass the `$callback`, otherwise false.
	 */
	function array_all( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		foreach ( $array as $key => $value ) {
			if ( ! $callback( $value, $key ) ) {
				return false;
			}
		}

		return true;
	}
}

if ( ! function_exists( 'array_first' ) ) {
	/**
	 * Polyfill for `array_first()` function added in PHP 8.5.
	 *
	 * Returns the first element of an array.
	 *
	 * @since 6.9.0
	 *
	 * @param array $array The array to get the first element from.
	 * @return mixed|null The first element of the array, or null if the array is empty.
	 */
	function array_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		if ( empty( $array ) ) {
			return null;
		}

		foreach ( $array as $value ) {
			return $value;
		}
	}
}

if ( ! function_exists( 'array_last' ) ) {
	/**
	 * Polyfill for `array_last()` function added in PHP 8.5.
	 *
	 * Returns the last element of an array.
	 *
	 * @since 6.9.0
	 *
	 * @param array $array The array to get the last element from.
	 * @return mixed|null The last element of the array, or null if the array is empty.
	 */
	function array_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
		if ( empty( $array ) ) {
			return null;
		}

		return $array[ array_key_last( $array ) ];
	}
}

// IMAGETYPE_AVIF constant is only defined in PHP 8.x or later.
if ( ! defined( 'IMAGETYPE_AVIF' ) ) {
	define( 'IMAGETYPE_AVIF', 19 );
}

// IMG_AVIF constant is only defined in PHP 8.x or later.
if ( ! defined( 'IMG_AVIF' ) ) {
	define( 'IMG_AVIF', IMAGETYPE_AVIF );
}

// IMAGETYPE_HEIF constant is only defined in PHP 8.5 or later.
if ( ! defined( 'IMAGETYPE_HEIF' ) ) {
	define( 'IMAGETYPE_HEIF', 20 );
}
<?

/**
 * Plugin API: WP_Hook class
 *
 * @package WordPress
 * @subpackage Plugin
 * @since 4.7.0
 */

/**
 * Core class used to implement action and filter hook functionality.
 *
 * @since 4.7.0
 *
 * @see Iterator
 * @see ArrayAccess
 */
#[AllowDynamicProperties]
final class WP_Hook implements Iterator, ArrayAccess {

	/**
	 * Hook callbacks.
	 *
	 * @since 4.7.0
	 * @var array
	 */
	public $callbacks = array();

	/**
	 * Priorities list.
	 *
	 * @since 6.4.0
	 * @var array
	 */
	protected $priorities = array();

	/**
	 * The priority keys of actively running iterations of a hook.
	 *
	 * @since 4.7.0
	 * @var array
	 */
	private $iterations = array();

	/**
	 * The current priority of actively running iterations of a hook.
	 *
	 * @since 4.7.0
	 * @var array
	 */
	private $current_priority = array();

	/**
	 * Number of levels this hook can be recursively called.
	 *
	 * @since 4.7.0
	 * @var int
	 */
	private $nesting_level = 0;

	/**
	 * Flag for if we're currently doing an action, rather than a filter.
	 *
	 * @since 4.7.0
	 * @var bool
	 */
	private $doing_action = false;

	/**
	 * Adds a callback function to a filter hook.
	 *
	 * @since 4.7.0
	 *
	 * @param string   $hook_name     The name of the filter to add the callback to.
	 * @param callable $callback      The callback to be run when the filter is applied.
	 * @param int      $priority      The order in which the functions associated with a particular filter
	 *                                are executed. Lower numbers correspond with earlier execution,
	 *                                and functions with the same priority are executed in the order
	 *                                in which they were added to the filter.
	 * @param int      $accepted_args The number of arguments the function accepts.
	 */
	public function add_filter( $hook_name, $callback, $priority, $accepted_args ) {
		if ( null === $priority ) {
			$priority = 0;
		}

		$idx = _wp_filter_build_unique_id( $hook_name, $callback, $priority );

		$priority_existed = isset( $this->callbacks[ $priority ] );

		$this->callbacks[ $priority ][ $idx ] = array(
			'function'      => $callback,
			'accepted_args' => (int) $accepted_args,
		);

		// If we're adding a new priority to the list, put them back in sorted order.
		if ( ! $priority_existed && count( $this->callbacks ) > 1 ) {
			ksort( $this->callbacks, SORT_NUMERIC );
		}

		$this->priorities = array_keys( $this->callbacks );

		if ( $this->nesting_level > 0 ) {
			$this->resort_active_iterations( $priority, $priority_existed );
		}
	}

	/**
	 * Handles resetting callback priority keys mid-iteration.
	 *
	 * @since 4.7.0
	 *
	 * @param false|int $new_priority     Optional. The priority of the new filter being added. Default false,
	 *                                    for no priority being added.
	 * @param bool      $priority_existed Optional. Flag for whether the priority already existed before the new
	 *                                    filter was added. Default false.
	 */
	private function resort_active_iterations( $new_priority = false, $priority_existed = false ) {
		$new_priorities = $this->priorities;

		// If there are no remaining hooks, clear out all running iterations.
		if ( ! $new_priorities ) {
			foreach ( $this->iterations as $index => $iteration ) {
				$this->iterations[ $index ] = $new_priorities;
			}

			return;
		}

		$min = min( $new_priorities );

		foreach ( $this->iterations as $index => &$iteration ) {
			$current = current( $iteration );

			// If we're already at the end of this iteration, just leave the array pointer where it is.
			if ( false === $current ) {
				continue;
			}

			$iteration = $new_priorities;

			if ( $current < $min ) {
				array_unshift( $iteration, $current );
				continue;
			}

			while ( current( $iteration ) < $current ) {
				if ( false === next( $iteration ) ) {
					break;
				}
			}

			// If we have a new priority that didn't exist, but ::apply_filters() or ::do_action() thinks it's the current priority...
			if ( $new_priority === $this->current_priority[ $index ] && ! $priority_existed ) {
				/*
				 * ...and the new priority is the same as what $this->iterations thinks is the previous
				 * priority, we need to move back to it.
				 */

				if ( false === current( $iteration ) ) {
					// If we've already moved off the end of the array, go back to the last element.
					$prev = end( $iteration );
				} else {
					// Otherwise, just go back to the previous element.
					$prev = prev( $iteration );
				}

				if ( false === $prev ) {
					// Start of the array. Reset, and go about our day.
					reset( $iteration );
				} elseif ( $new_priority !== $prev ) {
					// Previous wasn't the same. Move forward again.
					next( $iteration );
				}
			}
		}

		unset( $iteration );
	}

	/**
	 * Removes a callback function from a filter hook.
	 *
	 * @since 4.7.0
	 *
	 * @param string                $hook_name The filter hook to which the function to be removed is hooked.
	 * @param callable|string|array $callback  The callback to be removed from running when the filter is applied.
	 *                                         This method can be called unconditionally to speculatively remove
	 *                                         a callback that may or may not exist.
	 * @param int                   $priority  The exact priority used when adding the original filter callback.
	 * @return bool Whether the callback existed before it was removed.
	 */
	public function remove_filter( $hook_name, $callback, $priority ) {
		if ( null === $priority ) {
			$priority = 0;
		}

		$function_key = _wp_filter_build_unique_id( $hook_name, $callback, $priority );

		$exists = isset( $function_key, $this->callbacks[ $priority ][ $function_key ] );

		if ( $exists ) {
			unset( $this->callbacks[ $priority ][ $function_key ] );

			if ( ! $this->callbacks[ $priority ] ) {
				unset( $this->callbacks[ $priority ] );

				$this->priorities = array_keys( $this->callbacks );

				if ( $this->nesting_level > 0 ) {
					$this->resort_active_iterations();
				}
			}
		}

		return $exists;
	}

	/**
	 * Checks if a specific callback has been registered for this hook.
	 *
	 * When using the `$callback` argument, this function may return a non-boolean value
	 * that evaluates to false (e.g. 0), so use the `===` operator for testing the return value.
	 *
	 * @since 4.7.0
	 * @since 6.9.0 Added the `$priority` parameter.
	 *
	 * @param string                      $hook_name Optional. The name of the filter hook. Default empty.
	 * @param callable|string|array|false $callback  Optional. The callback to check for.
	 *                                               This method can be called unconditionally to speculatively check
	 *                                               a callback that may or may not exist. Default false.
	 * @param int|false                   $priority  Optional. The specific priority at which to check for the callback.
	 *                                               Default false.
	 * @return bool|int If `$callback` is omitted, returns boolean for whether the hook has
	 *                  anything registered. When checking a specific function, the priority
	 *                  of that hook is returned, or false if the function is not attached.
	 *                  If `$callback` and `$priority` are both provided, a boolean is returned
	 *                  for whether the specific function is registered at that priority.
	 */
	public function has_filter( $hook_name = '', $callback = false, $priority = false ) {
		if ( false === $callback ) {
			return $this->has_filters();
		}

		$function_key = _wp_filter_build_unique_id( $hook_name, $callback, false );

		if ( ! $function_key ) {
			return false;
		}

		if ( is_int( $priority ) ) {
			return isset( $this->callbacks[ $priority ][ $function_key ] );
		}

		foreach ( $this->callbacks as $callback_priority => $callbacks ) {
			if ( isset( $callbacks[ $function_key ] ) ) {
				return $callback_priority;
			}
		}

		return false;
	}

	/**
	 * Checks if any callbacks have been registered for this hook.
	 *
	 * @since 4.7.0
	 *
	 * @return bool True if callbacks have been registered for the current hook, otherwise false.
	 */
	public function has_filters() {
		foreach ( $this->callbacks as $callbacks ) {
			if ( $callbacks ) {
				return true;
			}
		}

		return false;
	}

	/**
	 * Removes all callbacks from the current filter.
	 *
	 * @since 4.7.0
	 *
	 * @param int|false $priority Optional. The priority number to remove. Default false.
	 */
	public function remove_all_filters( $priority = false ) {
		if ( ! $this->callbacks ) {
			return;
		}

		if ( false === $priority ) {
			$this->callbacks  = array();
			$this->priorities = array();
		} elseif ( isset( $this->callbacks[ $priority ] ) ) {
			unset( $this->callbacks[ $priority ] );
			$this->priorities = array_keys( $this->callbacks );
		}

		if ( $this->nesting_level > 0 ) {
			$this->resort_active_iterations();
		}
	}

	/**
	 * Calls the callback functions that have been added to a filter hook.
	 *
	 * @since 4.7.0
	 *
	 * @param mixed $value The value to filter.
	 * @param array $args  Additional parameters to pass to the callback functions.
	 *                     This array is expected to include $value at index 0.
	 * @return mixed The filtered value after all hooked functions are applied to it.
	 */
	public function apply_filters( $value, $args ) {
		if ( ! $this->callbacks ) {
			return $value;
		}

		$nesting_level = $this->nesting_level++;

		$this->iterations[ $nesting_level ] = $this->priorities;

		$num_args = count( $args );

		do {
			$this->current_priority[ $nesting_level ] = current( $this->iterations[ $nesting_level ] );

			$priority = $this->current_priority[ $nesting_level ];

			foreach ( $this->callbacks[ $priority ] as $the_ ) {
				if ( ! $this->doing_action ) {
					$args[0] = $value;
				}

				// Avoid the array_slice() if possible.
				if ( 0 === $the_['accepted_args'] ) {
					$value = call_user_func( $the_['function'] );
				} elseif ( $the_['accepted_args'] >= $num_args ) {
					$value = call_user_func_array( $the_['function'], $args );
				} else {
					$value = call_user_func_array( $the_['function'], array_slice( $args, 0, $the_['accepted_args'] ) );
				}
			}
		} while ( false !== next( $this->iterations[ $nesting_level ] ) );

		unset( $this->iterations[ $nesting_level ] );
		unset( $this->current_priority[ $nesting_level ] );

		--$this->nesting_level;

		return $value;
	}

	/**
	 * Calls the callback functions that have been added to an action hook.
	 *
	 * @since 4.7.0
	 *
	 * @param array $args Parameters to pass to the callback functions.
	 */
	public function do_action( $args ) {
		$this->doing_action = true;
		$this->apply_filters( '', $args );

		// If there are recursive calls to the current action, we haven't finished it until we get to the last one.
		if ( ! $this->nesting_level ) {
			$this->doing_action = false;
		}
	}

	/**
	 * Processes the functions hooked into the 'all' hook.
	 *
	 * @since 4.7.0
	 *
	 * @param array $args Arguments to pass to the hook callbacks. Passed by reference.
	 */
	public function do_all_hook( &$args ) {
		$nesting_level                      = $this->nesting_level++;
		$this->iterations[ $nesting_level ] = $this->priorities;

		do {
			$priority = current( $this->iterations[ $nesting_level ] );

			foreach ( $this->callbacks[ $priority ] as $the_ ) {
				call_user_func_array( $the_['function'], $args );
			}
		} while ( false !== next( $this->iterations[ $nesting_level ] ) );

		unset( $this->iterations[ $nesting_level ] );
		--$this->nesting_level;
	}

	/**
	 * Return the current priority level of the currently running iteration of the hook.
	 *
	 * @since 4.7.0
	 *
	 * @return int|false If the hook is running, return the current priority level.
	 *                   If it isn't running, return false.
	 */
	public function current_priority() {
		if ( false === current( $this->iterations ) ) {
			return false;
		}

		return current( current( $this->iterations ) );
	}

	/**
	 * Normalizes filters set up before WordPress has initialized to WP_Hook objects.
	 *
	 * The `$filters` parameter should be an array keyed by hook name, with values
	 * containing either:
	 *
	 *  - A `WP_Hook` instance
	 *  - An array of callbacks keyed by their priorities
	 *
	 * Examples:
	 *
	 *     $filters = array(
	 *         'wp_fatal_error_handler_enabled' => array(
	 *             10 => array(
	 *                 array(
	 *                     'accepted_args' => 0,
	 *                     'function'      => function() {
	 *                         return false;
	 *                     },
	 *                 ),
	 *             ),
	 *         ),
	 *     );
	 *
	 * @since 4.7.0
	 *
	 * @param array $filters Filters to normalize. See documentation above for details.
	 * @return WP_Hook[] Array of normalized filters.
	 */
	public static function build_preinitialized_hooks( $filters ) {
		/** @var WP_Hook[] $normalized */
		$normalized = array();

		foreach ( $filters as $hook_name => $callback_groups ) {
			if ( $callback_groups instanceof WP_Hook ) {
				$normalized[ $hook_name ] = $callback_groups;
				continue;
			}

			$hook = new WP_Hook();

			// Loop through callback groups.
			foreach ( $callback_groups as $priority => $callbacks ) {

				// Loop through callbacks.
				foreach ( $callbacks as $cb ) {
					$hook->add_filter( $hook_name, $cb['function'], $priority, $cb['accepted_args'] );
				}
			}

			$normalized[ $hook_name ] = $hook;
		}

		return $normalized;
	}

	/**
	 * Determines whether an offset value exists.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/arrayaccess.offsetexists.php
	 *
	 * @param mixed $offset An offset to check for.
	 * @return bool True if the offset exists, false otherwise.
	 */
	#[ReturnTypeWillChange]
	public function offsetExists( $offset ) {
		return isset( $this->callbacks[ $offset ] );
	}

	/**
	 * Retrieves a value at a specified offset.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/arrayaccess.offsetget.php
	 *
	 * @param mixed $offset The offset to retrieve.
	 * @return mixed If set, the value at the specified offset, null otherwise.
	 */
	#[ReturnTypeWillChange]
	public function offsetGet( $offset ) {
		return isset( $this->callbacks[ $offset ] ) ? $this->callbacks[ $offset ] : null;
	}

	/**
	 * Sets a value at a specified offset.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/arrayaccess.offsetset.php
	 *
	 * @param mixed $offset The offset to assign the value to.
	 * @param mixed $value The value to set.
	 */
	#[ReturnTypeWillChange]
	public function offsetSet( $offset, $value ) {
		if ( is_null( $offset ) ) {
			$this->callbacks[] = $value;
		} else {
			$this->callbacks[ $offset ] = $value;
		}

		$this->priorities = array_keys( $this->callbacks );
	}

	/**
	 * Unsets a specified offset.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/arrayaccess.offsetunset.php
	 *
	 * @param mixed $offset The offset to unset.
	 */
	#[ReturnTypeWillChange]
	public function offsetUnset( $offset ) {
		unset( $this->callbacks[ $offset ] );
		$this->priorities = array_keys( $this->callbacks );
	}

	/**
	 * Returns the current element.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/iterator.current.php
	 *
	 * @return array Of callbacks at current priority.
	 */
	#[ReturnTypeWillChange]
	public function current() {
		return current( $this->callbacks );
	}

	/**
	 * Moves forward to the next element.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/iterator.next.php
	 *
	 * @return array Of callbacks at next priority.
	 */
	#[ReturnTypeWillChange]
	public function next() {
		return next( $this->callbacks );
	}

	/**
	 * Returns the key of the current element.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/iterator.key.php
	 *
	 * @return mixed Returns current priority on success, or NULL on failure
	 */
	#[ReturnTypeWillChange]
	public function key() {
		return key( $this->callbacks );
	}

	/**
	 * Checks if current position is valid.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/iterator.valid.php
	 *
	 * @return bool Whether the current position is valid.
	 */
	#[ReturnTypeWillChange]
	public function valid() {
		return key( $this->callbacks ) !== null;
	}

	/**
	 * Rewinds the Iterator to the first element.
	 *
	 * @since 4.7.0
	 *
	 * @link https://www.php.net/manual/en/iterator.rewind.php
	 */
	#[ReturnTypeWillChange]
	public function rewind() {
		reset( $this->callbacks );
	}
}