for.
 * @param string $meta_key  Optional. Metadata key. If not specified, retrieve all metadata for
 *                          the specified object. Default empty string.
 * @param bool   $single    Optional. If true, return only the first value of the specified `$meta_key`.
 *                          This parameter has no effect if `$meta_key` is not specified. Default false.
 * @return mixed An array of values if `$single` is false.
 *               The value of the meta field if `$single` is true.
 *               False for an invalid `$object_id` (non-numeric, zero, or negative value),
 *               or if `$meta_type` is not specified.
 *               Null if the value does not exist.
 */
function get_metadata_raw( $meta_type, $object_id, $meta_key = '', $single = false ) {
	if ( ! $meta_type || ! is_numeric( $object_id ) ) {
		return false;
	}

	$object_id = absint( $object_id );
	if ( ! $object_id ) {
		return false;
	}

	/**
	 * Short-circuits the return value of a meta field.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible filter names include:
	 *
	 *  - `get_post_metadata`
	 *  - `get_comment_metadata`
	 *  - `get_term_metadata`
	 *  - `get_user_metadata`
	 *
	 * @since 3.1.0
	 * @since 5.5.0 Added the `$meta_type` parameter.
	 *
	 * @param mixed  $value     The value to return, either a single metadata value or an array
	 *                          of values depending on the value of `$single`. Default null.
	 * @param int    $object_id ID of the object metadata is for.
	 * @param string $meta_key  Metadata key.
	 * @param bool   $single    Whether to return only the first value of the specified `$meta_key`.
	 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                          or any other object type with an associated meta table.
	 */
	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single, $meta_type );
	if ( null !== $check ) {
		if ( $single && is_array( $check ) ) {
			return $check[0];
		} else {
			return $check;
		}
	}

	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );

	if ( ! $meta_cache ) {
		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
		if ( isset( $meta_cache[ $object_id ] ) ) {
			$meta_cache = $meta_cache[ $object_id ];
		} else {
			$meta_cache = null;
		}
	}

	if ( ! $meta_key ) {
		return $meta_cache;
	}

	if ( isset( $meta_cache[ $meta_key ] ) ) {
		if ( $single ) {
			return maybe_unserialize( $meta_cache[ $meta_key ][0] );
		} else {
			return array_map( 'maybe_unserialize', $meta_cache[ $meta_key ] );
		}
	}

	return null;
}

/**
 * Retrieves default metadata value for the specified meta key and object.
 *
 * By default, an empty string is returned if `$single` is true, or an empty array
 * if it's false.
 *
 * @since 5.5.0
 *
 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table.
 * @param int    $object_id ID of the object metadata is for.
 * @param string $meta_key  Metadata key.
 * @param bool   $single    Optional. If true, return only the first value of the specified `$meta_key`.
 *                          This parameter has no effect if `$meta_key` is not specified. Default false.
 * @return mixed An array of default values if `$single` is false.
 *               The default value of the meta field if `$single` is true.
 */
function get_metadata_default( $meta_type, $object_id, $meta_key, $single = false ) {
	if ( $single ) {
		$value = '';
	} else {
		$value = array();
	}

	/**
	 * Filters the default metadata value for a specified meta key and object.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 *
	 * Possible filter names include:
	 *
	 *  - `default_post_metadata`
	 *  - `default_comment_metadata`
	 *  - `default_term_metadata`
	 *  - `default_user_metadata`
	 *
	 * @since 5.5.0
	 *
	 * @param mixed  $value     The value to return, either a single metadata value or an array
	 *                          of values depending on the value of `$single`.
	 * @param int    $object_id ID of the object metadata is for.
	 * @param string $meta_key  Metadata key.
	 * @param bool   $single    Whether to return only the first value of the specified `$meta_key`.
	 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                          or any other object type with an associated meta table.
	 */
	$value = apply_filters( "default_{$meta_type}_metadata", $value, $object_id, $meta_key, $single, $meta_type );

	if ( ! $single && ! wp_is_numeric_array( $value ) ) {
		$value = array( $value );
	}

	return $value;
}

/**
 * Determines if a meta field with the given key exists for the given object ID.
 *
 * @since 3.3.0
 *
 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table.
 * @param int    $object_id ID of the object metadata is for.
 * @param string $meta_key  Metadata key.
 * @return bool Whether a meta field with the given key exists.
 */
function metadata_exists( $meta_type, $object_id, $meta_key ) {
	if ( ! $meta_type || ! is_numeric( $object_id ) ) {
		return false;
	}

	$object_id = absint( $object_id );
	if ( ! $object_id ) {
		return false;
	}

	/** This filter is documented in wp-includes/meta.php */
	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, true, $meta_type );
	if ( null !== $check ) {
		return (bool) $check;
	}

	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );

	if ( ! $meta_cache ) {
		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
		$meta_cache = $meta_cache[ $object_id ];
	}

	if ( isset( $meta_cache[ $meta_key ] ) ) {
		return true;
	}

	return false;
}

/**
 * Retrieves metadata by meta ID.
 *
 * @since 3.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table.
 * @param int    $meta_id   ID for a specific meta row.
 * @return stdClass|false {
 *     Metadata object, or boolean `false` if the metadata doesn't exist.
 *
 *     @type string $meta_key   The meta key.
 *     @type mixed  $meta_value The unserialized meta value.
 *     @type string $meta_id    Optional. The meta ID when the meta type is any value except 'user'.
 *     @type string $umeta_id   Optional. The meta ID when the meta type is 'user'.
 *     @type string $post_id    Optional. The object ID when the meta type is 'post'.
 *     @type string $comment_id Optional. The object ID when the meta type is 'comment'.
 *     @type string $term_id    Optional. The object ID when the meta type is 'term'.
 *     @type string $user_id    Optional. The object ID when the meta type is 'user'.
 * }
 */
function get_metadata_by_mid( $meta_type, $meta_id ) {
	global $wpdb;

	if ( ! $meta_type || ! is_numeric( $meta_id ) || floor( $meta_id ) != $meta_id ) {
		return false;
	}

	$meta_id = (int) $meta_id;
	if ( $meta_id <= 0 ) {
		return false;
	}

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	/**
	 * Short-circuits the return value when fetching a meta field by meta ID.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible hook names include:
	 *
	 *  - `get_post_metadata_by_mid`
	 *  - `get_comment_metadata_by_mid`
	 *  - `get_term_metadata_by_mid`
	 *  - `get_user_metadata_by_mid`
	 *
	 * @since 5.0.0
	 *
	 * @param stdClass|null $value   The value to return.
	 * @param int           $meta_id Meta ID.
	 */
	$check = apply_filters( "get_{$meta_type}_metadata_by_mid", null, $meta_id );
	if ( null !== $check ) {
		return $check;
	}

	$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

	$meta = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $table WHERE $id_column = %d", $meta_id ) );

	if ( empty( $meta ) ) {
		return false;
	}

	if ( isset( $meta->meta_value ) ) {
		$meta->meta_value = maybe_unserialize( $meta->meta_value );
	}

	return $meta;
}

/**
 * Updates metadata by meta ID.
 *
 * @since 3.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string       $meta_type  Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                                 or any other object type with an associated meta table.
 * @param int          $meta_id    ID for a specific meta row.
 * @param string       $meta_value Metadata value. Must be serializable if non-scalar.
 * @param string|false $meta_key   Optional. You can provide a meta key to update it. Default false.
 * @return bool True on successful update, false on failure.
 */
function update_metadata_by_mid( $meta_type, $meta_id, $meta_value, $meta_key = false ) {
	global $wpdb;

	// Make sure everything is valid.
	if ( ! $meta_type || ! is_numeric( $meta_id ) || floor( $meta_id ) != $meta_id ) {
		return false;
	}

	$meta_id = (int) $meta_id;
	if ( $meta_id <= 0 ) {
		return false;
	}

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	$column    = sanitize_key( $meta_type . '_id' );
	$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

	/**
	 * Short-circuits updating metadata of a specific type by meta ID.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible hook names include:
	 *
	 *  - `update_post_metadata_by_mid`
	 *  - `update_comment_metadata_by_mid`
	 *  - `update_term_metadata_by_mid`
	 *  - `update_user_metadata_by_mid`
	 *
	 * @since 5.0.0
	 *
	 * @param null|bool    $check      Whether to allow updating metadata for the given type.
	 * @param int          $meta_id    Meta ID.
	 * @param mixed        $meta_value Meta value. Must be serializable if non-scalar.
	 * @param string|false $meta_key   Meta key, if provided.
	 */
	$check = apply_filters( "update_{$meta_type}_metadata_by_mid", null, $meta_id, $meta_value, $meta_key );
	if ( null !== $check ) {
		return (bool) $check;
	}

	// Fetch the meta and go on if it's found.
	$meta = get_metadata_by_mid( $meta_type, $meta_id );
	if ( $meta ) {
		$original_key = $meta->meta_key;
		$object_id    = $meta->{$column};

		/*
		 * If a new meta_key (last parameter) was specified, change the meta key,
		 * otherwise use the original key in the update statement.
		 */
		if ( false === $meta_key ) {
			$meta_key = $original_key;
		} elseif ( ! is_string( $meta_key ) ) {
			return false;
		}

		$meta_subtype = get_object_subtype( $meta_type, $object_id );

		// Sanitize the meta.
		$_meta_value = $meta_value;
		$meta_value  = sanitize_meta( $meta_key, $meta_value, $meta_type, $meta_subtype );
		$meta_value  = maybe_serialize( $meta_value );

		// Format the data query arguments.
		$data = array(
			'meta_key'   => $meta_key,
			'meta_value' => $meta_value,
		);

		// Format the where query arguments.
		$where               = array();
		$where[ $id_column ] = $meta_id;

		/** This action is documented in wp-includes/meta.php */
		do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );

		if ( 'post' === $meta_type ) {
			/** This action is documented in wp-includes/meta.php */
			do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
		}

		// Run the update query, all fields in $data are %s, $where is a %d.
		$result = $wpdb->update( $table, $data, $where, '%s', '%d' );
		if ( ! $result ) {
			return false;
		}

		// Clear the caches.
		wp_cache_delete( $object_id, $meta_type . '_meta' );

		/** This action is documented in wp-includes/meta.php */
		do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );

		if ( 'post' === $meta_type ) {
			/** This action is documented in wp-includes/meta.php */
			do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
		}

		return true;
	}

	// And if the meta was not found.
	return false;
}

/**
 * Deletes metadata by meta ID.
 *
 * @since 3.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table.
 * @param int    $meta_id   ID for a specific meta row.
 * @return bool True on successful delete, false on failure.
 */
function delete_metadata_by_mid( $meta_type, $meta_id ) {
	global $wpdb;

	// Make sure everything is valid.
	if ( ! $meta_type || ! is_numeric( $meta_id ) || floor( $meta_id ) != $meta_id ) {
		return false;
	}

	$meta_id = (int) $meta_id;
	if ( $meta_id <= 0 ) {
		return false;
	}

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	// Object and ID columns.
	$column    = sanitize_key( $meta_type . '_id' );
	$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

	/**
	 * Short-circuits deleting metadata of a specific type by meta ID.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible hook names include:
	 *
	 *  - `delete_post_metadata_by_mid`
	 *  - `delete_comment_metadata_by_mid`
	 *  - `delete_term_metadata_by_mid`
	 *  - `delete_user_metadata_by_mid`
	 *
	 * @since 5.0.0
	 *
	 * @param null|bool $delete  Whether to allow metadata deletion of the given type.
	 * @param int       $meta_id Meta ID.
	 */
	$check = apply_filters( "delete_{$meta_type}_metadata_by_mid", null, $meta_id );
	if ( null !== $check ) {
		return (bool) $check;
	}

	// Fetch the meta and go on if it's found.
	$meta = get_metadata_by_mid( $meta_type, $meta_id );
	if ( $meta ) {
		$object_id = (int) $meta->{$column};

		/** This action is documented in wp-includes/meta.php */
		do_action( "delete_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );

		// Old-style action.
		if ( 'post' === $meta_type || 'comment' === $meta_type ) {
			/**
			 * Fires immediately before deleting post or comment metadata of a specific type.
			 *
			 * The dynamic portion of the hook name, `$meta_type`, refers to the meta
			 * object type (post or comment).
			 *
			 * Possible hook names include:
			 *
			 *  - `delete_postmeta`
			 *  - `delete_commentmeta`
			 *  - `delete_termmeta`
			 *  - `delete_usermeta`
			 *
			 * @since 3.4.0
			 *
			 * @param int $meta_id ID of the metadata entry to delete.
			 */
			do_action( "delete_{$meta_type}meta", $meta_id );
		}

		// Run the query, will return true if deleted, false otherwise.
		$result = (bool) $wpdb->delete( $table, array( $id_column => $meta_id ) );

		// Clear the caches.
		wp_cache_delete( $object_id, $meta_type . '_meta' );

		/** This action is documented in wp-includes/meta.php */
		do_action( "deleted_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );

		// Old-style action.
		if ( 'post' === $meta_type || 'comment' === $meta_type ) {
			/**
			 * Fires immediately after deleting post or comment metadata of a specific type.
			 *
			 * The dynamic portion of the hook name, `$meta_type`, refers to the meta
			 * object type (post or comment).
			 *
			 * Possible hook names include:
			 *
			 *  - `deleted_postmeta`
			 *  - `deleted_commentmeta`
			 *  - `deleted_termmeta`
			 *  - `deleted_usermeta`
			 *
			 * @since 3.4.0
			 *
			 * @param int $meta_id Deleted metadata entry ID.
			 */
			do_action( "deleted_{$meta_type}meta", $meta_id );
		}

		return $result;

	}

	// Meta ID was not found.
	return false;
}

/**
 * Updates the metadata cache for the specified objects.
 *
 * @since 2.9.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string       $meta_type  Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                                 or any other object type with an associated meta table.
 * @param string|int[] $object_ids Array or comma delimited list of object IDs to update cache for.
 * @return array|false Metadata cache for the specified objects, or false on failure.
 */
function update_meta_cache( $meta_type, $object_ids ) {
	global $wpdb;

	if ( ! $meta_type || ! $object_ids ) {
		return false;
	}

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	$column = sanitize_key( $meta_type . '_id' );

	if ( ! is_array( $object_ids ) ) {
		$object_ids = preg_replace( '|[^0-9,]|', '', $object_ids );
		$object_ids = explode( ',', $object_ids );
	}

	$object_ids = array_map( 'intval', $object_ids );

	/**
	 * Short-circuits updating the metadata cache of a specific type.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible hook names include:
	 *
	 *  - `update_post_metadata_cache`
	 *  - `update_comment_metadata_cache`
	 *  - `update_term_metadata_cache`
	 *  - `update_user_metadata_cache`
	 *
	 * @since 5.0.0
	 *
	 * @param mixed $check      Whether to allow updating the meta cache of the given type.
	 * @param int[] $object_ids Array of object IDs to update the meta cache for.
	 */
	$check = apply_filters( "update_{$meta_type}_metadata_cache", null, $object_ids );
	if ( null !== $check ) {
		return (bool) $check;
	}

	$cache_key      = $meta_type . '_meta';
	$non_cached_ids = array();
	$cache          = array();
	$cache_values   = wp_cache_get_multiple( $object_ids, $cache_key );

	foreach ( $cache_values as $id => $cached_object ) {
		if ( false === $cached_object ) {
			$non_cached_ids[] = $id;
		} else {
			$cache[ $id ] = $cached_object;
		}
	}

	if ( empty( $non_cached_ids ) ) {
		return $cache;
	}

	// Get meta info.
	$id_list   = implode( ',', $non_cached_ids );
	$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

	$meta_list = $wpdb->get_results( "SELECT $column, meta_key, meta_value FROM $table WHERE $column IN ($id_list) ORDER BY $id_column ASC", ARRAY_A );

	if ( ! empty( $meta_list ) ) {
		foreach ( $meta_list as $metarow ) {
			$mpid = (int) $metarow[ $column ];
			$mkey = $metarow['meta_key'];
			$mval = $metarow['meta_value'];

			// Force subkeys to be array type.
			if ( ! isset( $cache[ $mpid ] ) || ! is_array( $cache[ $mpid ] ) ) {
				$cache[ $mpid ] = array();
			}
			if ( ! isset( $cache[ $mpid ][ $mkey ] ) || ! is_array( $cache[ $mpid ][ $mkey ] ) ) {
				$cache[ $mpid ][ $mkey ] = array();
			}

			// Add a value to the current pid/key.
			$cache[ $mpid ][ $mkey ][] = $mval;
		}
	}

	$data = array();
	foreach ( $non_cached_ids as $id ) {
		if ( ! isset( $cache[ $id ] ) ) {
			$cache[ $id ] = array();
		}
		$data[ $id ] = $cache[ $id ];
	}
	wp_cache_add_multiple( $data, $cache_key );

	return $cache;
}

/**
 * Retrieves the queue for lazy-loading metadata.
 *
 * @since 4.5.0
 *
 * @return WP_Metadata_Lazyloader Metadata lazyloader queue.
 */
function wp_metadata_lazyloader() {
	static $wp_metadata_lazyloader;

	if ( null === $wp_metadata_lazyloader ) {
		$wp_metadata_lazyloader = new WP_Metadata_Lazyloader();
	}

	return $wp_metadata_lazyloader;
}

/**
 * Given a meta query, generates SQL clauses to be appended to a main query.
 *
 * @since 3.2.0
 *
 * @see WP_Meta_Query
 *
 * @param array  $meta_query        A meta query.
 * @param string $type              Type of meta.
 * @param string $primary_table     Primary database table name.
 * @param string $primary_id_column Primary ID column name.
 * @param object $context           Optional. The main query object. Default null.
 * @return string[]|false {
 *     Array containing JOIN and WHERE SQL clauses to append to the main query,
 *     or false if no table exists for the requested meta type.
 *
 *     @type string $join  SQL fragment to append to the main JOIN clause.
 *     @type string $where SQL fragment to append to the main WHERE clause.
 * }
 */
function get_meta_sql( $meta_query, $type, $primary_table, $primary_id_column, $context = null ) {
	$meta_query_obj = new WP_Meta_Query( $meta_query );
	return $meta_query_obj->get_sql( $type, $primary_table, $primary_id_column, $context );
}

/**
 * Retrieves the name of the metadata table for the specified object type.
 *
 * @since 2.9.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                     or any other object type with an associated meta table.
 * @return string|false Metadata table name, or false if no metadata table exists
 */
function _get_meta_table( $type ) {
	global $wpdb;

	$table_name = $type . 'meta';

	if ( empty( $wpdb->$table_name ) ) {
		return false;
	}

	return $wpdb->$table_name;
}

/**
 * Determines whether a meta key is considered protected.
 *
 * @since 3.1.3
 *
 * @param string $meta_key  Metadata key.
 * @param string $meta_type Optional. Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table. Default empty string.
 * @return bool Whether the meta key is considered protected.
 */
function is_protected_meta( $meta_key, $meta_type = '' ) {
	$sanitized_key = preg_replace( "/[^\x20-\x7E\p{L}]/", '', $meta_key );
	$protected     = strlen( $sanitized_key ) > 0 && ( '_' === $sanitized_key[0] );

	/**
	 * Filters whether a meta key is considered protected.
	 *
	 * @since 3.2.0
	 *
	 * @param bool   $protected Whether the key is considered protected.
	 * @param string $meta_key  Metadata key.
	 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                          or any other object type with an associated meta table.
	 */
	return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );
}

/**
 * Sanitizes meta value.
 *
 * @since 3.1.3
 * @since 4.9.8 The `$object_subtype` parameter was added.
 *
 * @param string $meta_key       Metadata key.
 * @param mixed  $meta_value     Metadata value to sanitize.
 * @param string $object_type    Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                               or any other object type with an associated meta table.
 * @param string $object_subtype Optional. The subtype of the object type. Default empty string.
 * @return mixed Sanitized $meta_value.
 */
function sanitize_meta( $meta_key, $meta_value, $object_type, $object_subtype = '' ) {
	if ( ! empty( $object_subtype ) && has_filter( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}" ) ) {

		/**
		 * Filters the sanitization of a specific meta key of a specific meta type and subtype.
		 *
		 * The dynamic portions of the hook name, `$object_type`, `$meta_key`,
		 * and `$object_subtype`, refer to the metadata object type (comment, post, term, or user),
		 * the meta key value, and the object subtype respectively.
		 *
		 * @since 4.9.8
		 *
		 * @param mixed  $meta_value     Metadata value to sanitize.
		 * @param string $meta_key       Metadata key.
		 * @param string $object_type    Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
		 *                               or any other object type with an associated meta table.
		 * @param string $object_subtype Object subtype.
		 */
		return apply_filters( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $meta_value, $meta_key, $object_type, $object_subtype );
	}

	/**
	 * Filters the sanitization of a specific meta key of a specific meta type.
	 *
	 * The dynamic portions of the hook name, `$meta_type`, and `$meta_key`,
	 * refer to the metadata object type (comment, post, term, or user) and the meta
	 * key value, respectively.
	 *
	 * @since 3.3.0
	 *
	 * @param mixed  $meta_value  Metadata value to sanitize.
	 * @param string $meta_key    Metadata key.
	 * @param string $object_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                            or any other object type with an associated meta table.
	 */
	return apply_filters( "sanitize_{$object_type}_meta_{$meta_key}", $meta_value, $meta_key, $object_type );
}

/**
 * Registers a meta key.
 *
 * It is recommended to register meta keys for a specific combination of object type and object subtype. If passing
 * an object subtype is omitted, the meta key will be registered for the entire object type, however it can be partly
 * overridden in case a more specific meta key of the same name exists for the same object type and a subtype.
 *
 * If an object type does not support any subtypes, such as users or comments, you should commonly call this function
 * without passing a subtype.
 *
 * @since 3.3.0
 * @since 4.6.0 {@link https://core.trac.wordpress.org/ticket/35658 Modified
 *              to support an array of data to attach to registered meta keys}. Previous arguments for
 *              `$sanitize_callback` and `$auth_callback` have been folded into this array.
 * @since 4.9.8 The `$object_subtype` argument was added to the arguments array.
 * @since 5.3.0 Valid meta types expanded to include "array" and "object".
 * @since 5.5.0 The `$default` argument was added to the arguments array.
 *
 * @param string       $object_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                                  or any other object type with an associated meta table.
 * @param string       $meta_key    Meta key to register.
 * @param array        $args {
 *     Data used to describe the meta key when registered.
 *
 *     @type string     $object_subtype    A subtype; e.g. if the object type is "post", the post type. If left empty,
 *                                         the meta key will be registered on the entire object type. Default empty.
 *     @type string     $type              The type of data associated with this meta key.
 *                                         Valid values are 'string', 'boolean', 'integer', 'number', 'array', and 'object'.
 *     @type string     $description       A description of the data attached to this meta key.
 *     @type bool       $single            Whether the meta key has one value per object, or an array of values per object.
 *     @type mixed      $default           The default value returned from get_metadata() if no value has been set yet.
 *                                         When using a non-single meta key, the default value is for the first entry.
 *                                         In other words, when calling get_metadata() with `$single` set to `false`,
 *                                         the default value given here will be wrapped in an array.
 *     @type callable   $sanitize_callback A function or method to call when sanitizing `$meta_key` data.
 *     @type callable   $auth_callback     Optional. A function or method to call when performing edit_post_meta,
 *                                         add_post_meta, and delete_post_meta capability checks.
 *     @type bool|array $show_in_rest      Whether data associated with this meta key can be considered public and
 *                                         should be accessible via the REST API. A custom post type must also declare
 *                                         support for custom fields for registered meta to be accessible via REST.
 *                                         When registering complex meta values this argument may optionally be an
 *                                         array with 'schema' or 'prepare_callback' keys instead of a boolean.
 * }
 * @param string|array $deprecated Deprecated. Use `$args` instead.
 * @return bool True if the meta key was successfully registered in the global array, false if not.
 *              Registering a meta key with distinct sanitize and auth callbacks will fire those callbacks,
 *              but will not add to the global registry.
 */
function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {
	global $wp_meta_keys;

	if ( ! is_array( $wp_meta_keys ) ) {
		$wp_meta_keys = array();
	}

	$defaults = array(
		'object_subtype'    => '',
		'type'              => 'string',
		'description'       => '',
		'default'           => '',
		'single'            => false,
		'sanitize_callback' => null,
		'auth_callback'     => null,
		'show_in_rest'      => false,
	);

	// There used to be individual args for sanitize and auth callbacks.
	$has_old_sanitize_cb = false;
	$has_old_auth_cb     = false;

	if ( is_callable( $args ) ) {
		$args = array(
			'sanitize_callback' => $args,
		);

		$has_old_sanitize_cb = true;
	} else {
		$args = (array) $args;
	}

	if ( is_callable( $deprecated ) ) {
		$args['auth_callback'] = $deprecated;
		$has_old_auth_cb       = true;
	}

	/**
	 * Filters the registration arguments when registering meta.
	 *
	 * @since 4.6.0
	 *
	 * @param array  $args        Array of meta registration arguments.
	 * @param array  $defaults    Array of default arguments.
	 * @param string $object_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                            or any other object type with an associated meta table.
	 * @param string $meta_key    Meta key.
	 */
	$args = apply_filters( 'register_meta_args', $args, $defaults, $object_type, $meta_key );
	unset( $defaults['default'] );
	$args = wp_parse_args( $args, $defaults );

	// Require an item schema when registering array meta.
	if ( false !== $args['show_in_rest'] && 'array' === $args['type'] ) {
		if ( ! is_array( $args['show_in_rest'] ) || ! isset( $args['show_in_rest']['schema']['items'] ) ) {
			_doing_it_wrong( __FUNCTION__, __( 'When registering an "array" meta type to show in the REST API, you must specify the schema for each array item in "show_in_rest.schema.items".' ), '5.3.0' );

			return false;
		}
	}

	$object_subtype = ! empty( $args['object_subtype'] ) ? $args['object_subtype'] : '';

	// If `auth_callback` is not provided, fall back to `is_protected_meta()`.
	if ( empty( $args['auth_callback'] ) ) {
		if ( is_protected_meta( $meta_key, $object_type ) ) {
			$args['auth_callback'] = '__return_false';
		} else {
			$args['auth_callback'] = '__return_true';
		}
	}

	// Back-compat: old sanitize and auth callbacks are applied to all of an object type.
	if ( is_callable( $args['sanitize_callback'] ) ) {
		if ( ! empty( $object_subtype ) ) {
			add_filter( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['sanitize_callback'], 10, 4 );
		} else {
			add_filter( "sanitize_{$object_type}_meta_{$meta_key}", $args['sanitize_callback'], 10, 3 );
		}
	}

	if ( is_callable( $args['auth_callback'] ) ) {
		if ( ! empty( $object_subtype ) ) {
			add_filter( "auth_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['auth_callback'], 10, 6 );
		} else {
			add_filter( "auth_{$object_type}_meta_{$meta_key}", $args['auth_callback'], 10, 6 );
		}
	}

	if ( array_key_exists( 'default', $args ) ) {
		$schema = $args;
		if ( is_array( $args['show_in_rest'] ) && isset( $args['show_in_rest']['schema'] ) ) {
			$schema = array_merge( $schema, $args['show_in_rest']['schema'] );
		}

		$check = rest_validate_value_from_schema( $args['default'], $schema );
		if ( is_wp_error( $check ) ) {
			_doing_it_wrong( __FUNCTION__, __( 'When registering a default meta value the data must match the type provided.' ), '5.5.0' );

			return false;
		}

		if ( ! has_filter( "default_{$object_type}_metadata", 'filter_default_metadata' ) ) {
			add_filter( "default_{$object_type}_metadata", 'filter_default_metadata', 10, 5 );
		}
	}

	// Global registry only contains meta keys registered with the array of arguments added in 4.6.0.
	if ( ! $has_old_auth_cb && ! $has_old_sanitize_cb ) {
		unset( $args['object_subtype'] );

		$wp_meta_keys[ $object_type ][ $object_subtype ][ $meta_key ] = $args;

		return true;
	}

	return false;
}

/**
 * Filters into default_{$object_type}_metadata and adds in default value.
 *
 * @since 5.5.0
 *
 * @param mixed  $value     Current value passed to filter.
 * @param int    $object_id ID of the object metadata is for.
 * @param string $meta_key  Metadata key.
 * @param bool   $single    If true, return only the first value of the specified `$meta_key`.
 *                          This parameter has no effect if `$meta_key` is not specified.
 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                          or any other object type with an associated meta table.
 * @return mixed An array of default values if `$single` is false.
 *               The default value of the meta field if `$single` is true.
 */
function filter_default_metadata( $value, $object_id, $meta_key, $single, $meta_type ) {
	global $wp_meta_keys;

	if ( wp_installing() ) {
		return $value;
	}

	if ( ! is_array( $wp_meta_keys ) || ! isset( $wp_meta_keys[ $meta_type ] ) ) {
		return $value;
	}

	$defaults = array();
	foreach ( $wp_meta_keys[ $meta_type ] as $sub_type => $meta_data ) {
		foreach ( $meta_data as $_meta_key => $args ) {
			if ( $_meta_key === $meta_key && array_key_exists( 'default', $args ) ) {
				$defaults[ $sub_type ] = $args;
			}
		}
	}

	if ( ! $defaults ) {
		return $value;
	}

	// If this meta type does not have subtypes, then the default is keyed as an empty string.
	if ( isset( $defaults[''] ) ) {
		$metadata = $defaults[''];
	} else {
		$sub_type = get_object_subtype( $meta_type, $object_id );
		if ( ! isset( $defaults[ $sub_type ] ) ) {
			return $value;
		}
		$metadata = $defaults[ $sub_type ];
	}

	if ( $single ) {
		$value = $metadata['default'];
	} else {
		$value = array( $metadata['default'] );
	}

	return $value;
}

/**
 * Checks if a meta key is registered.
 *
 * @since 4.6.0
 * @since 4.9.8 The `$object_subtype` parameter was added.
 *
 * @param string $object_type    Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                               or any other object type with an associated meta table.
 * @param string $meta_key       Metadata key.
 * @param string $object_subtype Optional. The subtype of the object type. Default empty string.
 * @return bool True if the meta key is registered to the object type and, if provided,
 *              the object subtype. False if not.
 */
function registered_meta_key_exists( $object_type, $meta_key, $object_subtype = '' ) {
	$meta_keys = get_registered_meta_keys( $object_type, $object_subtype );

	return isset( $meta_keys[ $meta_key ] );
}

/**
 * Unregisters a meta key from the list of registered keys.
 *
 * @since 4.6.0
 * @since 4.9.8 The `$object_subtype` parameter was added.
 *
 * @param string $object_type    Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                               or any other object type with an associated meta table.
 * @param string $meta_key       Metadata key.
 * @param string $object_subtype Optional. The subtype of the object type. Default empty string.
 * @return bool True if successful. False if the meta key was not registered.
 */
function unregister_meta_key( $object_type, $meta_key, $object_subtype = '' ) {
	global $wp_meta_keys;

	if ( ! registered_meta_key_exists( $object_type, $meta_key, $object_subtype ) ) {
		return false;
	}

	$args = $wp_meta_keys[ $object_type ][ $object_subtype ][ $meta_key ];

	if ( isset( $args['sanitize_callback'] ) && is_callable( $args['sanitize_callback'] ) ) {
		if ( ! empty( $object_subtype ) ) {
			remove_filter( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['sanitize_callback'] );
		} else {
			remove_filter( "sanitize_{$object_type}_meta_{$meta_key}", $args['sanitize_callback'] );
		}
	}

	if ( isset( $args['auth_callback'] ) && is_callable( $args['auth_callback'] ) ) {
		if ( ! empty( $object_subtype ) ) {
			remove_filter( "auth_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['auth_callback'] );
		} else {
			remove_filter( "auth_{$object_type}_meta_{$meta_key}", $args['auth_callback'] );
		}
	}

	unset( $wp_meta_keys[ $object_type ][ $object_subtype ][ $meta_key ] );

	// Do some clean up.
	if ( empty( $wp_meta_keys[ $object_type ][ $object_subtype ] ) ) {
		unset( $wp_meta_keys[ $object_type ][ $object_subtype ] );
	}
	if ( empty( $wp_meta_keys[ $object_type ] ) ) {
		unset( $wp_meta_keys[ $object_type ] );
	}

	return true;
}

/**
 * Retrieves a list of registered metadata args for an object type, keyed by their meta keys.
 *
 * @since 4.6.0
 * @since 4.9.8 The `$object_subtype` parameter was added.
 *
 * @param string $object_type    Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                               or any other object type with an associated meta table.
 * @param string $object_subtype Optional. The subtype of the object type. Default empty string.
 * @return array[] List of registered metadata args, keyed by their meta keys.
 */
function get_registered_meta_keys( $object_type, $object_subtype = '' ) {
	global $wp_meta_keys;

	if ( ! is_array( $wp_meta_keys ) || ! isset( $wp_meta_keys[ $object_type ] ) || ! isset( $wp_meta_keys[ $object_type ][ $object_subtype ] ) ) {
		return array();
	}

	return $wp_meta_keys[ $object_type ][ $object_subtype ];
}

/**
 * Retrieves registered metadata for a specified object.
 *
 * The results include both meta that is registered specifically for the
 * object's subtype and meta that is registered for the entire object type.
 *
 * @since 4.6.0
 *
 * @param string $object_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                            or any other object type with an associated meta table.
 * @param int    $object_id   ID of the object the metadata is for.
 * @param string $meta_key    Optional. Registered metadata key. If not specified, retrieve all registered
 *                            metadata for the specified object.
 * @return mixed A single value or array of values for a key if specified. An array of all registered keys
 *               and values for an object ID if not. False if a given $meta_key is not registered.
 */
function get_registered_metadata( $object_type, $object_id, $meta_key = '' ) {
	$object_subtype = get_object_subtype( $object_type, $object_id );

	if ( ! empty( $meta_key ) ) {
		if ( ! empty( $object_subtype ) && ! registered_meta_key_exists( $object_type, $meta_key, $object_subtype ) ) {
			$object_subtype = '';
		}

		if ( ! registered_meta_key_exists( $object_type, $meta_key, $object_subtype ) ) {
			return false;
		}

		$meta_keys     = get_registered_meta_keys( $object_type, $object_subtype );
		$meta_key_data = $meta_keys[ $meta_key ];

		$data = get_metadata( $object_type, $object_id, $meta_key, $meta_key_data['single'] );

		return $data;
	}

	$data = get_metadata( $object_type, $object_id );
	if ( ! $data ) {
		return array();
	}

	$meta_keys = get_registered_meta_keys( $object_type );
	if ( ! empty( $object_subtype ) ) {
		$meta_keys = array_merge( $meta_keys, get_registered_meta_keys( $object_type, $object_subtype ) );
	}

	return array_intersect_key( $data, $meta_keys );
}

/**
 * Filters out `register_meta()` args based on an allowed list.
 *
 * `register_meta()` args may change over time, so requiring the allowed list
 * to be explicitly turned off is a warranty seal of sorts.
 *
 * @access private
 * @since 5.5.0
 *
 * @param array $args         Arguments from `register_meta()`.
 * @param array $default_args Default arguments for `register_meta()`.
 * @return array Filtered arguments.
 */
function _wp_register_meta_args_allowed_list( $args, $default_args ) {
	return array_intersect_key( $args, $default_args );
}

/**
 * Returns the object subtype for a given object ID of a specific type.
 *
 * @since 4.9.8
 *
 * @param string $object_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
 *                            or any other object type with an associated meta table.
 * @param int    $object_id   ID of the object to retrieve its subtype.
 * @return string The object subtype or an empty string if unspecified subtype.
 */
function get_object_subtype( $object_type, $object_id ) {
	$object_id      = (int) $object_id;
	$object_subtype = '';

	switch ( $object_type ) {
		case 'post':
			$post_type = get_post_type( $object_id );

			if ( ! empty( $post_type ) ) {
				$object_subtype = $post_type;
			}
			break;

		case 'term':
			$term = get_term( $object_id );
			if ( ! $term instanceof WP_Term ) {
				break;
			}

			$object_subtype = $term->taxonomy;
			break;

		case 'comment':
			$comment = get_comment( $object_id );
			if ( ! $comment ) {
				break;
			}

			$object_subtype = 'comment';
			break;

		case 'user':
			$user = get_user_by( 'id', $object_id );
			if ( ! $user ) {
				break;
			}

			$object_subtype = 'user';
			break;
	}

	/**
	 * Filters the object subtype identifier for a non-standard object type.
	 *
	 * The dynamic portion of the hook name, `$object_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 *
	 * Possible hook names include:
	 *
	 *  - `get_object_subtype_post`
	 *  - `get_object_subtype_comment`
	 *  - `get_object_subtype_term`
	 *  - `get_object_subtype_user`
	 *
	 * @since 4.9.8
	 *
	 * @param string $object_subtype Empty string to override.
	 * @param int    $object_id      ID of the object to get the subtype for.
	 */
	return apply_filters( "get_object_subtype_{$object_type}", $object_subtype, $object_id );
}
e = new WP_Error( 'http_request_not_executed', __( 'User has blocked requests through HTTP.' ) );
			/** This action is documented in wp-includes/class-wp-http.php */
			do_action( 'http_api_debug', $response, 'response', 'WpOrg\Requests\Requests', $parsed_args, $url );
			return $response;
		}

		// If we are streaming to a file but no filename was given drop it in the WP temp dir
		// and pick its name using the basename of the $url.
		if ( $parsed_args['stream'] ) {
			if ( empty( $parsed_args['filename'] ) ) {
				$parsed_args['filename'] = get_temp_dir() . basename( $url );
			}

			// Force some settings if we are streaming to a file and check for existence
			// and perms of destination directory.
			$parsed_args['blocking'] = true;
			if ( ! wp_is_writable( dirname( $parsed_args['filename'] ) ) ) {
				$response = new WP_Error( 'http_request_failed', __( 'Destination directory for file streaming does not exist or is not writable.' ) );
				/** This action is documented in wp-includes/class-wp-http.php */
				do_action( 'http_api_debug', $response, 'response', 'WpOrg\Requests\Requests', $parsed_args, $url );
				return $response;
			}
		}

		if ( is_null( $parsed_args['headers'] ) ) {
			$parsed_args['headers'] = array();
		}

		// WP allows passing in headers as a string, weirdly.
		if ( ! is_array( $parsed_args['headers'] ) ) {
			$processed_headers      = WP_Http::processHeaders( $parsed_args['headers'] );
			$parsed_args['headers'] = $processed_headers['headers'];
		}

		// Setup arguments.
		$headers = $parsed_args['headers'];
		$data    = $parsed_args['body'];
		$type    = $parsed_args['method'];
		$options = array(
			'timeout'   => $parsed_args['timeout'],
			'useragent' => $parsed_args['user-agent'],
			'blocking'  => $parsed_args['blocking'],
			'hooks'     => new WP_HTTP_Requests_Hooks( $url, $parsed_args ),
		);

		// Ensure redirects follow browser behavior.
		$options['hooks']->register( 'requests.before_redirect', array( get_class(), 'browser_redirect_compatibility' ) );

		// Validate redirected URLs.
		if ( function_exists( 'wp_kses_bad_protocol' ) && $parsed_args['reject_unsafe_urls'] ) {
			$options['hooks']->register( 'requests.before_redirect', array( get_class(), 'validate_redirects' ) );
		}

		if ( $parsed_args['stream'] ) {
			$options['filename'] = $parsed_args['filename'];
		}
		if ( empty( $parsed_args['redirection'] ) ) {
			$options['follow_redirects'] = false;
		} else {
			$options['redirects'] = $parsed_args['redirection'];
		}

		// Use byte limit, if we can.
		if ( isset( $parsed_args['limit_response_size'] ) ) {
			$options['max_bytes'] = $parsed_args['limit_response_size'];
		}

		// If we've got cookies, use and convert them to WpOrg\Requests\Cookie.
		if ( ! empty( $parsed_args['cookies'] ) ) {
			$options['cookies'] = WP_Http::normalize_cookies( $parsed_args['cookies'] );
		}

		// SSL certificate handling.
		if ( ! $parsed_args['sslverify'] ) {
			$options['verify']     = false;
			$options['verifyname'] = false;
		} else {
			$options['verify'] = $parsed_args['sslcertificates'];
		}

		// All non-GET/HEAD requests should put the arguments in the form body.
		if ( 'HEAD' !== $type && 'GET' !== $type ) {
			$options['data_format'] = 'body';
		}

		/**
		 * Filters whether SSL should be verified for non-local requests.
		 *
		 * @since 2.8.0
		 * @since 5.1.0 The `$url` parameter was added.
		 *
		 * @param bool|string $ssl_verify Boolean to control whether to verify the SSL connection
		 *                                or path to an SSL certificate.
		 * @param string      $url        The request URL.
		 */
		$options['verify'] = apply_filters( 'https_ssl_verify', $options['verify'], $url );

		// Check for proxies.
		$proxy = new WP_HTTP_Proxy();
		if ( $proxy->is_enabled() && $proxy->send_through_proxy( $url ) ) {
			$options['proxy'] = new WpOrg\Requests\Proxy\Http( $proxy->host() . ':' . $proxy->port() );

			if ( $proxy->use_authentication() ) {
				$options['proxy']->use_authentication = true;
				$options['proxy']->user               = $proxy->username();
				$options['proxy']->pass               = $proxy->password();
			}
		}

		// Avoid issues where mbstring.func_overload is enabled.
		mbstring_binary_safe_encoding();

		try {
			$requests_response = WpOrg\Requests\Requests::request( $url, $headers, $data, $type, $options );

			// Convert the response into an array.
			$http_response = new WP_HTTP_Requests_Response( $requests_response, $parsed_args['filename'] );
			$response      = $http_response->to_array();

			// Add the original object to the array.
			$response['http_response'] = $http_response;
		} catch ( WpOrg\Requests\Exception $e ) {
			$response = new WP_Error( 'http_request_failed', $e->getMessage() );
		}

		reset_mbstring_encoding();

		/**
		 * Fires after an HTTP API response is received and before the response is returned.
		 *
		 * @since 2.8.0
		 *
		 * @param array|WP_Error $response    HTTP response or WP_Error object.
		 * @param string         $context     Context under which the hook is fired.
		 * @param string         $class       HTTP transport used.
		 * @param array          $parsed_args HTTP request arguments.
		 * @param string         $url         The request URL.
		 */
		do_action( 'http_api_debug', $response, 'response', 'WpOrg\Requests\Requests', $parsed_args, $url );
		if ( is_wp_error( $response ) ) {
			return $response;
		}

		if ( ! $parsed_args['blocking'] ) {
			return array(
				'headers'       => array(),
				'body'          => '',
				'response'      => array(
					'code'    => false,
					'message' => false,
				),
				'cookies'       => array(),
				'http_response' => null,
			);
		}

		/**
		 * Filters a successful HTTP API response immediately before the response is returned.
		 *
		 * @since 2.9.0
		 *
		 * @param array  $response    HTTP response.
		 * @param array  $parsed_args HTTP request arguments.
		 * @param string $url         The request URL.
		 */
		return apply_filters( 'http_response', $response, $parsed_args, $url );
	}

	/**
	 * Normalizes cookies for using in Requests.
	 *
	 * @since 4.6.0
	 *
	 * @param array $cookies Array of cookies to send with the request.
	 * @return WpOrg\Requests\Cookie\Jar Cookie holder object.
	 */
	public static function normalize_cookies( $cookies ) {
		$cookie_jar = new WpOrg\Requests\Cookie\Jar();

		foreach ( $cookies as $name => $value ) {
			if ( $value instanceof WP_Http_Cookie ) {
				$attributes                 = array_filter(
					$value->get_attributes(),
					static function( $attr ) {
						return null !== $attr;
					}
				);
				$cookie_jar[ $value->name ] = new WpOrg\Requests\Cookie( $value->name, $value->value, $attributes, array( 'host-only' => $value->host_only ) );
			} elseif ( is_scalar( $value ) ) {
				$cookie_jar[ $name ] = new WpOrg\Requests\Cookie( $name, (string) $value );
			}
		}

		return $cookie_jar;
	}

	/**
	 * Match redirect behavior to browser handling.
	 *
	 * Changes 302 redirects from POST to GET to match browser handling. Per
	 * RFC 7231, user agents can deviate from the strict reading of the
	 * specification for compatibility purposes.
	 *
	 * @since 4.6.0
	 *
	 * @param string                  $location URL to redirect to.
	 * @param array                   $headers  Headers for the redirect.
	 * @param string|array            $data     Body to send with the request.
	 * @param array                   $options  Redirect request options.
	 * @param WpOrg\Requests\Response $original Response object.
	 */
	public static function browser_redirect_compatibility( $location, $headers, $data, &$options, $original ) {
		// Browser compatibility.
		if ( 302 === $original->status_code ) {
			$options['type'] = WpOrg\Requests\Requests::GET;
		}
	}

	/**
	 * Validate redirected URLs.
	 *
	 * @since 4.7.5
	 *
	 * @throws WpOrg\Requests\Exception On unsuccessful URL validation.
	 * @param string $location URL to redirect to.
	 */
	public static function validate_redirects( $location ) {
		if ( ! wp_http_validate_url( $location ) ) {
			throw new WpOrg\Requests\Exception( __( 'A valid URL was not provided.' ), 'wp_http.redirect_failed_validation' );
		}
	}

	/**
	 * Tests which transports are capable of supporting the request.
	 *
	 * @since 3.2.0
	 *
	 * @param array  $args Request arguments.
	 * @param string $url  URL to request.
	 * @return string|false Class name for the first transport that claims to support the request.
	 *                      False if no transport claims to support the request.
	 */
	public function _get_first_available_transport( $args, $url = null ) {
		$transports = array( 'curl', 'streams' );

		/**
		 * Filters which HTTP transports are available and in what order.
		 *
		 * @since 3.7.0
		 *
		 * @param string[] $transports Array of HTTP transports to check. Default array contains
		 *                             'curl' and 'streams', in that order.
		 * @param array    $args       HTTP request arguments.
		 * @param string   $url        The URL to request.
		 */
		$request_order = apply_filters( 'http_api_transports', $transports, $args, $url );

		// Loop over each transport on each HTTP request looking for one which will serve this request's needs.
		foreach ( $request_order as $transport ) {
			if ( in_array( $transport, $transports, true ) ) {
				$transport = ucfirst( $transport );
			}
			$class = 'WP_Http_' . $transport;

			// Check to see if this transport is a possibility, calls the transport statically.
			if ( ! call_user_func( array( $class, 'test' ), $args, $url ) ) {
				continue;
			}

			return $class;
		}

		return false;
	}

	/**
	 * Dispatches a HTTP request to a supporting transport.
	 *
	 * Tests each transport in order to find a transport which matches the request arguments.
	 * Also caches the transport instance to be used later.
	 *
	 * The order for requests is cURL, and then PHP Streams.
	 *
	 * @since 3.2.0
	 * @deprecated 5.1.0 Use WP_Http::request()
	 * @see WP_Http::request()
	 *
	 * @param string $url  URL to request.
	 * @param array  $args Request arguments.
	 * @return array|WP_Error Array containing 'headers', 'body', 'response', 'cookies', 'filename'.
	 *                        A WP_Error instance upon error.
	 */
	private function _dispatch_request( $url, $args ) {
		static $transports = array();

		$class = $this->_get_first_available_transport( $args, $url );
		if ( ! $class ) {
			return new WP_Error( 'http_failure', __( 'There are no HTTP transports available which can complete the requested request.' ) );
		}

		// Transport claims to support request, instantiate it and give it a whirl.
		if ( empty( $transports[ $class ] ) ) {
			$transports[ $class ] = new $class();
		}

		$response = $transports[ $class ]->request( $url, $args );

		/** This action is documented in wp-includes/class-wp-http.php */
		do_action( 'http_api_debug', $response, 'response', $class, $args, $url );

		if ( is_wp_error( $response ) ) {
			return $response;
		}

		/** This filter is documented in wp-includes/class-wp-http.php */
		return apply_filters( 'http_response', $response, $args, $url );
	}

	/**
	 * Uses the POST HTTP method.
	 *
	 * Used for sending data that is expected to be in the body.
	 *
	 * @since 2.7.0
	 *
	 * @param string       $url  The request URL.
	 * @param string|array $args Optional. Override the defaults.
	 * @return array|WP_Error Array containing 'headers', 'body', 'response', 'cookies', 'filename'.
	 *                        A WP_Error instance upon error.
	 */
	public function post( $url, $args = array() ) {
		$defaults    = array( 'method' => 'POST' );
		$parsed_args = wp_parse_args( $args, $defaults );
		return $this->request( $url, $parsed_args );
	}

	/**
	 * Uses the GET HTTP method.
	 *
	 * Used for sending data that is expected to be in the body.
	 *
	 * @since 2.7.0
	 *
	 * @param string       $url  The request URL.
	 * @param string|array $args Optional. Override the defaults.
	 * @return array|WP_Error Array containing 'headers', 'body', 'response', 'cookies', 'filename'.
	 *                        A WP_Error instance upon error.
	 */
	public function get( $url, $args = array() ) {
		$defaults    = array( 'method' => 'GET' );
		$parsed_args = wp_parse_args( $args, $defaults );
		return $this->request( $url, $parsed_args );
	}

	/**
	 * Uses the HEAD HTTP method.
	 *
	 * Used for sending data that is expected to be in the body.
	 *
	 * @since 2.7.0
	 *
	 * @param string       $url  The request URL.
	 * @param string|array $args Optional. Override the defaults.
	 * @return array|WP_Error Array containing 'headers', 'body', 'response', 'cookies', 'filename'.
	 *                        A WP_Error instance upon error.
	 */
	public function head( $url, $args = array() ) {
		$defaults    = array( 'method' => 'HEAD' );
		$parsed_args = wp_parse_args( $args, $defaults );
		return $this->request( $url, $parsed_args );
	}

	/**
	 * Parses the responses and splits the parts into headers and body.
	 *
	 * @since 2.7.0
	 *
	 * @param string $response The full response string.
	 * @return array {
	 *     Array with response headers and body.
	 *
	 *     @type string $headers HTTP response headers.
	 *     @type string $body    HTTP response body.
	 * }
	 */
	public static function processResponse( $response ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.MethodNameInvalid
		$response = explode( "\r\n\r\n", $response, 2 );

		return array(
			'headers' => $response[0],
			'body'    => isset( $response[1] ) ? $response[1] : '',
		);
	}

	/**
	 * Transforms header string into an array.
	 *
	 * @since 2.7.0
	 *
	 * @param string|array $headers The original headers. If a string is passed, it will be converted
	 *                              to an array. If an array is passed, then it is assumed to be
	 *                              raw header data with numeric keys with the headers as the values.
	 *                              No headers must be passed that were already processed.
	 * @param string       $url     Optional. The URL that was requested. Default empty.
	 * @return array {
	 *     Processed string headers. If duplicate headers are encountered,
	 *     then a numbered array is returned as the value of that header-key.
	 *
	 *     @type array            $response {
	 *         @type int    $code    The response status code. Default 0.
	 *         @type string $message The response message. Default empty.
	 *     }
	 *     @type array            $newheaders The processed header data as a multidimensional array.
	 *     @type WP_Http_Cookie[] $cookies    If the original headers contain the 'Set-Cookie' key,
	 *                                        an array containing `WP_Http_Cookie` objects is returned.
	 * }
	 */
	public static function processHeaders( $headers, $url = '' ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.MethodNameInvalid
		// Split headers, one per array element.
		if ( is_string( $headers ) ) {
			// Tolerate line terminator: CRLF = LF (RFC 2616 19.3).
			$headers = str_replace( "\r\n", "\n", $headers );
			/*
			 * Unfold folded header fields. LWS = [CRLF] 1*( SP | HT ) <US-ASCII SP, space (32)>,
			 * <US-ASCII HT, horizontal-tab (9)> (RFC 2616 2.2).
			 */
			$headers = preg_replace( '/\n[ \t]/', ' ', $headers );
			// Create the headers array.
			$headers = explode( "\n", $headers );
		}

		$response = array(
			'code'    => 0,
			'message' => '',
		);

		/*
		 * If a redirection has taken place, The headers for each page request may have been passed.
		 * In this case, determine the final HTTP header and parse from there.
		 */
		for ( $i = count( $headers ) - 1; $i >= 0; $i-- ) {
			if ( ! empty( $headers[ $i ] ) && ! str_contains( $headers[ $i ], ':' ) ) {
				$headers = array_splice( $headers, $i );
				break;
			}
		}

		$cookies    = array();
		$newheaders = array();
		foreach ( (array) $headers as $tempheader ) {
			if ( empty( $tempheader ) ) {
				continue;
			}

			if ( ! str_contains( $tempheader, ':' ) ) {
				$stack   = explode( ' ', $tempheader, 3 );
				$stack[] = '';
				list( , $response['code'], $response['message']) = $stack;
				continue;
			}

			list($key, $value) = explode( ':', $tempheader, 2 );

			$key   = strtolower( $key );
			$value = trim( $value );

			if ( isset( $newheaders[ $key ] ) ) {
				if ( ! is_array( $newheaders[ $key ] ) ) {
					$newheaders[ $key ] = array( $newheaders[ $key ] );
				}
				$newheaders[ $key ][] = $value;
			} else {
				$newheaders[ $key ] = $value;
			}
			if ( 'set-cookie' === $key ) {
				$cookies[] = new WP_Http_Cookie( $value, $url );
			}
		}

		// Cast the Response Code to an int.
		$response['code'] = (int) $response['code'];

		return array(
			'response' => $response,
			'headers'  => $newheaders,
			'cookies'  => $cookies,
		);
	}

	/**
	 * Takes the arguments for a ::request() and checks for the cookie array.
	 *
	 * If it's found, then it upgrades any basic name => value pairs to WP_Http_Cookie instances,
	 * which are each parsed into strings and added to the Cookie: header (within the arguments array).
	 * Edits the array by reference.
	 *
	 * @since 2.8.0
	 *
	 * @param array $r Full array of args passed into ::request()
	 */
	public static function buildCookieHeader( &$r ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.MethodNameInvalid
		if ( ! empty( $r['cookies'] ) ) {
			// Upgrade any name => value cookie pairs to WP_HTTP_Cookie instances.
			foreach ( $r['cookies'] as $name => $value ) {
				if ( ! is_object( $value ) ) {
					$r['cookies'][ $name ] = new WP_Http_Cookie(
						array(
							'name'  => $name,
							'value' => $value,
						)
					);
				}
			}

			$cookies_header = '';
			foreach ( (array) $r['cookies'] as $cookie ) {
				$cookies_header .= $cookie->getHeaderValue() . '; ';
			}

			$cookies_header         = substr( $cookies_header, 0, -2 );
			$r['headers']['cookie'] = $cookies_header;
		}
	}

	/**
	 * Decodes chunk transfer-encoding, based off the HTTP 1.1 specification.
	 *
	 * Based off the HTTP http_encoding_dechunk function.
	 *
	 * @link https://tools.ietf.org/html/rfc2616#section-19.4.6 Process for chunked decoding.
	 *
	 * @since 2.7.0
	 *
	 * @param string $body Body content.
	 * @return string Chunked decoded body on success or raw body on failure.
	 */
	public static function chunkTransferDecode( $body ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.MethodNameInvalid
		// The body is not chunked encoded or is malformed.
		if ( ! preg_match( '/^([0-9a-f]+)[^\r\n]*\r\n/i', trim( $body ) ) ) {
			return $body;
		}

		$parsed_body = '';

		// We'll be altering $body, so need a backup in case of error.
		$body_original = $body;

		while ( true ) {
			$has_chunk = (bool) preg_match( '/^([0-9a-f]+)[^\r\n]*\r\n/i', $body, $match );
			if ( ! $has_chunk || empty( $match[1] ) ) {
				return $body_original;
			}

			$length       = hexdec( $match[1] );
			$chunk_length = strlen( $match[0] );

			// Parse out the chunk of data.
			$parsed_body .= substr( $body, $chunk_length, $length );

			// Remove the chunk from the raw data.
			$body = substr( $body, $length + $chunk_length );

			// End of the document.
			if ( '0' === trim( $body ) ) {
				return $parsed_body;
			}
		}
	}

	/**
	 * Determines whether an HTTP API request to the given URL should be blocked.
	 *
	 * Those who are behind a proxy and want to prevent access to certain hosts may do so. This will
	 * prevent plugins from working and core functionality, if you don't include `api.wordpress.org`.
	 *
	 * You block external URL requests by defining `WP_HTTP_BLOCK_EXTERNAL` as true in your `wp-config.php`
	 * file and this will only allow localhost and your site to make requests. The constant
	 * `WP_ACCESSIBLE_HOSTS` will allow additional hosts to go through for requests. The format of the
	 * `WP_ACCESSIBLE_HOSTS` constant is a comma separated list of hostnames to allow, wildcard domains
	 * are supported, eg `*.wordpress.org` will allow for all subdomains of `wordpress.org` to be contacted.
	 *
	 * @since 2.8.0
	 *
	 * @link https://core.trac.wordpress.org/ticket/8927 Allow preventing external requests.
	 * @link https://core.trac.wordpress.org/ticket/14636 Allow wildcard domains in WP_ACCESSIBLE_HOSTS
	 *
	 * @param string $uri URI of url.
	 * @return bool True to block, false to allow.
	 */
	public function block_request( $uri ) {
		// We don't need to block requests, because nothing is blocked.
		if ( ! defined( 'WP_HTTP_BLOCK_EXTERNAL' ) || ! WP_HTTP_BLOCK_EXTERNAL ) {
			return false;
		}

		$check = parse_url( $uri );
		if ( ! $check ) {
			return true;
		}

		$home = parse_url( get_option( 'siteurl' ) );

		// Don't block requests back to ourselves by default.
		if ( 'localhost' === $check['host'] || ( isset( $home['host'] ) && $home['host'] === $check['host'] ) ) {
			/**
			 * Filters whether to block local HTTP API requests.
			 *
			 * A local request is one to `localhost` or to the same host as the site itself.
			 *
			 * @since 2.8.0
			 *
			 * @param bool $block Whether to block local requests. Default false.
			 */
			return apply_filters( 'block_local_requests', false );
		}

		if ( ! defined( 'WP_ACCESSIBLE_HOSTS' ) ) {
			return true;
		}

		static $accessible_hosts = null;
		static $wildcard_regex   = array();
		if ( null === $accessible_hosts ) {
			$accessible_hosts = preg_split( '|,\s*|', WP_ACCESSIBLE_HOSTS );

			if ( str_contains( WP_ACCESSIBLE_HOSTS, '*' ) ) {
				$wildcard_regex = array();
				foreach ( $accessible_hosts as $host ) {
					$wildcard_regex[] = str_replace( '\*', '.+', preg_quote( $host, '/' ) );
				}
				$wildcard_regex = '/^(' . implode( '|', $wildcard_regex ) . ')$/i';
			}
		}

		if ( ! empty( $wildcard_regex ) ) {
			return ! preg_match( $wildcard_regex, $check['host'] );
		} else {
			return ! in_array( $check['host'], $accessible_hosts, true ); // Inverse logic, if it's in the array, then don't block it.
		}

	}

	/**
	 * Used as a wrapper for PHP's parse_url() function that handles edgecases in < PHP 5.4.7.
	 *
	 * @deprecated 4.4.0 Use wp_parse_url()
	 * @see wp_parse_url()
	 *
	 * @param string $url The URL to parse.
	 * @return bool|array False on failure; Array of URL components on success;
	 *                    See parse_url()'s return values.
	 */
	protected static function parse_url( $url ) {
		_deprecated_function( __METHOD__, '4.4.0', 'wp_parse_url()' );
		return wp_parse_url( $url );
	}

	/**
	 * Converts a relative URL to an absolute URL relative to a given URL.
	 *
	 * If an Absolute URL is provided, no processing of that URL is done.
	 *
	 * @since 3.4.0
	 *
	 * @param string $maybe_relative_path The URL which might be relative.
	 * @param string $url                 The URL which $maybe_relative_path is relative to.
	 * @return string An Absolute URL, in a failure condition where the URL cannot be parsed, the relative URL will be returned.
	 */
	public static function make_absolute_url( $maybe_relative_path, $url ) {
		if ( empty( $url ) ) {
			return $maybe_relative_path;
		}

		$url_parts = wp_parse_url( $url );
		if ( ! $url_parts ) {
			return $maybe_relative_path;
		}

		$relative_url_parts = wp_parse_url( $maybe_relative_path );
		if ( ! $relative_url_parts ) {
			return $maybe_relative_path;
		}

		// Check for a scheme on the 'relative' URL.
		if ( ! empty( $relative_url_parts['scheme'] ) ) {
			return $maybe_relative_path;
		}

		$absolute_path = $url_parts['scheme'] . '://';

		// Schemeless URLs will make it this far, so we check for a host in the relative URL
		// and convert it to a protocol-URL.
		if ( isset( $relative_url_parts['host'] ) ) {
			$absolute_path .= $relative_url_parts['host'];
			if ( isset( $relative_url_parts['port'] ) ) {
				$absolute_path .= ':' . $relative_url_parts['port'];
			}
		} else {
			$absolute_path .= $url_parts['host'];
			if ( isset( $url_parts['port'] ) ) {
				$absolute_path .= ':' . $url_parts['port'];
			}
		}

		// Start off with the absolute URL path.
		$path = ! empty( $url_parts['path'] ) ? $url_parts['path'] : '/';

		// If it's a root-relative path, then great.
		if ( ! empty( $relative_url_parts['path'] ) && '/' === $relative_url_parts['path'][0] ) {
			$path = $relative_url_parts['path'];

			// Else it's a relative path.
		} elseif ( ! empty( $relative_url_parts['path'] ) ) {
			// Strip off any file components from the absolute path.
			$path = substr( $path, 0, strrpos( $path, '/' ) + 1 );

			// Build the new path.
			$path .= $relative_url_parts['path'];

			// Strip all /path/../ out of the path.
			while ( strpos( $path, '../' ) > 1 ) {
				$path = preg_replace( '![^/]+/\.\./!', '', $path );
			}

			// Strip any final leading ../ from the path.
			$path = preg_replace( '!^/(\.\./)+!', '', $path );
		}

		// Add the query string.
		if ( ! empty( $relative_url_parts['query'] ) ) {
			$path .= '?' . $relative_url_parts['query'];
		}

		// Add the fragment.
		if ( ! empty( $relative_url_parts['fragment'] ) ) {
			$path .= '#' . $relative_url_parts['fragment'];
		}

		return $absolute_path . '/' . ltrim( $path, '/' );
	}

	/**
	 * Handles an HTTP redirect and follows it if appropriate.
	 *
	 * @since 3.7.0
	 *
	 * @param string $url      The URL which was requested.
	 * @param array  $args     The arguments which were used to make the request.
	 * @param array  $response The response of the HTTP request.
	 * @return array|false|WP_Error An HTTP API response array if the redirect is successfully followed,
	 *                              false if no redirect is present, or a WP_Error object if there's an error.
	 */
	public static function handle_redirects( $url, $args, $response ) {
		// If no redirects are present, or, redirects were not requested, perform no action.
		if ( ! isset( $response['headers']['location'] ) || 0 === $args['_redirection'] ) {
			return false;
		}

		// Only perform redirections on redirection http codes.
		if ( $response['response']['code'] > 399 || $response['response']['code'] < 300 ) {
			return false;
		}

		// Don't redirect if we've run out of redirects.
		if ( $args['redirection']-- <= 0 ) {
			return new WP_Error( 'http_request_failed', __( 'Too many redirects.' ) );
		}

		$redirect_location = $response['headers']['location'];

		// If there were multiple Location headers, use the last header specified.
		if ( is_array( $redirect_location ) ) {
			$redirect_location = array_pop( $redirect_location );
		}

		$redirect_location = WP_Http::make_absolute_url( $redirect_location, $url );

		// POST requests should not POST to a redirected location.
		if ( 'POST' === $args['method'] ) {
			if ( in_array( $response['response']['code'], array( 302, 303 ), true ) ) {
				$args['method'] = 'GET';
			}
		}

		// Include valid cookies in the redirect process.
		if ( ! empty( $response['cookies'] ) ) {
			foreach ( $response['cookies'] as $cookie ) {
				if ( $cookie->test( $redirect_location ) ) {
					$args['cookies'][] = $cookie;
				}
			}
		}

		return wp_remote_request( $redirect_location, $args );
	}

	/**
	 * Determines if a specified string represents an IP address or not.
	 *
	 * This function also detects the type of the IP address, returning either
	 * '4' or '6' to represent an IPv4 and IPv6 address respectively.
	 * This does not verify if the IP is a valid IP, only that it appears to be
	 * an IP address.
	 *
	 * @link http://home.deds.nl/~aeron/regex/ for IPv6 regex.
	 *
	 * @since 3.7.0
	 *
	 * @param string $maybe_ip A suspected IP address.
	 * @return int|false Upon success, '4' or '6' to represent an IPv4 or IPv6 address, false upon failure.
	 */
	public static function is_ip_address( $maybe_ip ) {
		if ( preg_match( '/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/', $maybe_ip ) ) {
			return 4;
		}

		if ( str_contains( $maybe_ip, ':' ) && preg_match( '/^(((?=.*(::))(?!.*\3.+\3))\3?|([\dA-F]{1,4}(\3|:\b|$)|\2))(?4){5}((?4){2}|(((2[0-4]|1\d|[1-9])?\d|25[0-5])\.?\b){4})$/i', trim( $maybe_ip, ' []' ) ) ) {
			return 6;
		}

		return false;
	}

}