seb86/Auto-Load-Next-Post

<?php
/**
 * Auto Load Next Post - Autoloader.
 *
 * @since    1.5.0
 * @author   Sébastien Dumont
 * @category Classes
 * @package  Auto Load Next Post/Classes/AutoLoader
 * @license  GPL-2.0+
 *
 * @note This class was forked from WooCommerce and modified.
 */

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

if ( ! class_exists( 'ALNP_Autoloader' ) ) {

    class ALNP_Autoloader {

        /**
         * Path to the includes directory.
         *
         * @access private
         * @var    string
         */
        private $include_path = '';

        /**
         * The Constructor.
         */
        public function __construct() {
            if ( function_exists( '__autoload' ) ) {
                spl_autoload_register( '__autoload' );
            }

            spl_autoload_register( array( $this, 'autoload' ) );

            $this->include_path = untrailingslashit( plugin_dir_path( AUTO_LOAD_NEXT_POST_FILE ) ) . '/includes/';
        }

        /**
         * Take a class name and turn it into a file name.
         *
         * @access private
         * @param  string $class Class name.
         * @return string
         */
        private function get_file_name_from_class( $class ) {
            return 'class-' . str_replace( '_', '-', $class ) . '.php';
        } // END get_file_name_from_class()

        /**
         * Include a class file.
         *
         * @access private
         * @param  string $path File path.
         * @return bool Successful or not.
         */
        private function load_file( $path ) {
            if ( $path && is_readable( $path ) ) {
                include_once $path;
                return true;
            }
            return false;
        } // END load_file()

        /**
         * Auto-load ALNP classes on demand to reduce memory consumption.
         *
         * @access public
         * @param  string $class Class name.
         */
        public function autoload( $class ) {
            $class = strtolower( $class );

            if ( 0 !== strpos( $class, 'alnp_' ) ) {
                return;
            }

            $file = $this->get_file_name_from_class( $class );
            $path = '';

            if ( 0 === strpos( $class, 'alnp_admin' ) ) {
                $path = $this->include_path . 'admin/';
            }

            if ( empty( $path ) || ! $this->load_file( $path . $file ) ) {
                $this->load_file( $this->include_path . $file );
            }
        } // END autoload()

    } // END class.

} // END if class exists.

new ALNP_Autoloader();