<?php
/**
 * Acumenpopup Autoloader
 *
 * PSR-4-like autoloader for the Acumenpopup plugin.
 * Automatically loads classes based on namespace and file path.
 *
 * @since      1.0.0
 * @package    Acumenpopup
 * @subpackage Acumenpopup/includes
 */

namespace Acumenpopup;

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Class Autoloader
 *
 * Handles automatic class loading using SPL autoload.
 *
 * @since   1.0.0
 * @package Acumenpopup
 */
class Autoloader {

	/**
	 * The single instance of the class.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    Autoloader|null
	 */
	private static $instance = null;

	/**
	 * The base namespace for the plugin.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    string
	 */
	private $namespace = 'Acumenpopup';

	/**
	 * The base directory for the plugin classes.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    string
	 */
	private $base_dir;

	/**
	 * Class mapping for special cases.
	 *
	 * Maps class names to their file paths for non-standard locations.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    array
	 */
	private $class_map = array();

	/**
	 * Private constructor to prevent direct instantiation.
	 *
	 * @since  1.0.0
	 * @access private
	 */
	private function __construct() {
		$this->base_dir = ACUMENPOPUP_PLUGIN_DIR . 'includes/';
		$this->register();
	}

	/**
	 * Get the single instance of the Autoloader.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return Autoloader The single instance.
	 */
	public static function get_instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new self();
		}

		return self::$instance;
	}

	/**
	 * Register the autoloader with SPL.
	 *
	 * @since  1.0.0
	 * @access private
	 *
	 * @return void
	 */
	private function register() {
		spl_autoload_register( array( $this, 'autoload' ) );
	}

	/**
	 * Add a class to the class map.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @param string $class    The fully qualified class name.
	 * @param string $filepath The file path for the class.
	 *
	 * @return void
	 */
	public function add_class_map( $class, $filepath ) {
		$this->class_map[ $class ] = $filepath;
	}

	/**
	 * Autoload callback function.
	 *
	 * Called by SPL autoloader when a class needs to be loaded.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @param string $class The fully qualified class name.
	 *
	 * @return void
	 */
	public function autoload( $class ) {
		// Check if the class is in our namespace.
		if ( 0 !== strpos( $class, $this->namespace . '\\' ) ) {
			return;
		}

		// Check class map first.
		if ( isset( $this->class_map[ $class ] ) ) {
			$file = $this->class_map[ $class ];
			if ( file_exists( $file ) ) {
				require_once $file;
				return;
			}
		}

		// Remove the base namespace from the class name.
		$relative_class = substr( $class, strlen( $this->namespace . '\\' ) );

		// Convert namespace separators to directory separators.
		$relative_path = str_replace( '\\', '/', $relative_class );

		// Convert class name format (e.g., Dynamic_Style -> Dynamic_Style).
		$file = $this->base_dir . $relative_path . '.php';

		// Load the file if it exists.
		if ( file_exists( $file ) ) {
			require_once $file;
		}
	}

	/**
	 * Prevent cloning of the instance.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function __clone() {
		_doing_it_wrong(
			__FUNCTION__,
			esc_html__( 'Cloning is forbidden.', 'acumen-popup' ),
			'1.0.0'
		);
	}

	/**
	 * Prevent unserializing of the instance.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function __wakeup() {
		_doing_it_wrong(
			__FUNCTION__,
			esc_html__( 'Unserializing is forbidden.', 'acumen-popup' ),
			'1.0.0'
		);
	}
}