<?php
if ( ! class_exists( 'WP_Scoped_Hooks' ) ) {

	/**
	 * Allows a temporary hook environment to be created for a given timeframe (i.e. scope), where any hooks
	 * added or removed will be recognised only during the specified scope. After the given scope, the
	 * original WordPress hook environment is restored to its previous state.
	 *
	 * @author    Barn2 Media <info@barn2.co.uk>
	 * @license   GPL-3.0
	 * @copyright Barn2 Media Ltd
	 * @version   1.3
	 */
	class WP_Scoped_Hooks {

		private $hooks;
		private $start_hook;
		private $end_hook;

		public function __construct( $start_hook = '', $end_hook = '' ) {
			$this->initialize();
			$this->set_scope( $start_hook, $end_hook );
		}

		private function initialize() {
			$this->hooks = array(
				'added' => array(),
				'removed' => array()
			);

			if ( $this->start_hook ) {
				remove_action( $this->start_hook, array( $this, 'register' ) );
			}
			if ( $this->end_hook ) {
				remove_action( $this->end_hook, array( $this, 'reset' ) );
			}
		}

		public function add_action( $tag, $function, $priority = 10, $accepted_args = 1 ) {
			$this->add_filter( $tag, $function, $priority, $accepted_args );
		}

		public function add_filter( $tag, $function, $priority = 10, $accepted_args = 1 ) {
			$this->hooks['added'][] = array( $tag, $function, $priority, $accepted_args );
		}

		public function remove_action( $tag, $function, $priority = 10, $accepted_args = 1 ) {
			$this->remove_filter( $tag, $function, $priority, $accepted_args );
		}

		public function remove_filter( $tag, $function, $priority = 10, $accepted_args = 1 ) {
			$this->hooks['removed'][] = array( $tag, $function, $priority, $accepted_args );
		}

		public function set_scope( $start_hook, $end_hook ) {
			if ( $start_hook && $end_hook ) {
				$this->start_hook	 = $start_hook;
				$this->end_hook		 = $end_hook;

				add_action( $start_hook, array( $this, 'register' ) );
				add_action( $end_hook, array( $this, 'reset' ) );
			}
		}

		public function register() {
			array_walk( $this->hooks['added'], array( $this, 'array_walk_add_filter' ) );
			$this->hooks['removed'] = array_filter( $this->hooks['removed'], array( $this, 'array_walk_remove_filter' ) );
		}

		public function reset() {
			array_walk( $this->hooks['added'], array( $this, 'array_walk_remove_filter' ) );
			array_walk( $this->hooks['removed'], array( $this, 'array_walk_add_filter' ) );

			$this->initialize();
		}

		private function array_walk_add_filter( $hook ) {
			add_filter( $hook[0], $hook[1], $hook[2], $hook[3] );
		}

		private function array_walk_remove_filter( $hook ) {
			return remove_filter( $hook[0], $hook[1], $hook[2], $hook[3] );
		}

	}

	// WP_Scoped_Hooks
}