<?php
/**
 * Admin-only includes bootstrapper.
 *
 * @package AIContentByParallax
 */

namespace AIContentByParallax\Admin;

defined( 'ABSPATH' ) || exit;

/**
 * Loads admin-only core includes when required by Parallax AI screens or AJAX.
 */
class AdminIncludes {

	/**
	 * AJAX actions that render WP_List_Table instances.
	 *
	 * @var string[]
	 */
	private const LIST_TABLE_AJAX_ACTIONS = array(
		'ai_content_by_parallax_ajax_load_approval_table',
		'ai_content_by_parallax_ajax_refresh_batreqs_prods',
		'ai_content_by_parallax_ajax_refresh_batreqs_cats',
		'ai_content_by_parallax_ajax_refresh_batreqdets_prod',
		'ai_content_by_parallax_ajax_refresh_batreqdets_cat',
		'ai_content_by_parallax_ajax_toggle_hide_optimized',
	);

	/**
	 * Register admin include bootstrapper.
	 */
	public static function register(): void {
		if ( is_admin() ) {
			add_action( 'admin_init', array( self::class, 'bootstrap_admin' ) );
		}

		if ( defined( 'WP_CLI' ) && WP_CLI ) {
			self::bootstrap_cli();
		}
	}

	/**
	 * Bootstrap admin-only includes on admin_init.
	 */
	public static function bootstrap_admin(): void {
		if ( wp_doing_ajax() ) {
			self::maybe_include_for_ajax();
		}

		add_action( 'current_screen', array( self::class, 'maybe_include_for_screen' ) );
	}

	/**
	 * Bootstrap includes for WP-CLI commands that reuse admin tables.
	 */
	private static function bootstrap_cli(): void {
		self::include_list_table();
	}

	/**
	 * Include admin-only files for the current Parallax admin screen.
	 *
	 * @param \WP_Screen $screen Current screen instance.
	 */
	public static function maybe_include_for_screen( $screen ): void {
		if ( ! self::is_parallax_screen( $screen ) ) {
			return;
		}

		self::include_list_table();
		self::ensure_file_helpers_loaded();
	}

	/**
	 * Include admin-only files for Parallax AJAX list table requests.
	 */
	private static function maybe_include_for_ajax(): void {
		$action = self::get_ajax_action();
		if ( '' === $action ) {
			return;
		}

		if ( in_array( $action, self::LIST_TABLE_AJAX_ACTIONS, true ) ) {
			self::include_list_table();
		}
	}

	/**
	 * Include WP_List_Table when required.
	 */
	private static function include_list_table(): void {
		if ( class_exists( 'WP_List_Table', false ) ) {
			return;
		}

		require_once ABSPATH . 'wp-admin/includes/class-wp-list-table.php';
	}

	/**
	 * Include WordPress file helper classes when required.
	 */
	private static function ensure_file_helpers_loaded(): void {
		if ( class_exists( 'WP_Filesystem_Direct', false ) ) {
			return;
		}

		require_once ABSPATH . 'wp-admin/includes/file.php';
	}

	/**
	 * Determine whether the current screen belongs to the plugin.
	 *
	 * @param mixed $screen Current screen instance.
	 * @return bool
	 */
	private static function is_parallax_screen( $screen ): bool {
		if ( is_object( $screen ) && isset( $screen->id ) ) {
			$screen_id = (string) $screen->id;
			if ( '' !== $screen_id && false !== strpos( $screen_id, 'ai-content-by-parallax' ) ) {
				return true;
			}
		}

		$page = filter_input( INPUT_GET, 'page', FILTER_SANITIZE_FULL_SPECIAL_CHARS );
		return is_string( $page ) && 'ai-content-by-parallax' === sanitize_key( $page );
	}

	/**
	 * Retrieve the current AJAX action key.
	 *
	 * @return string
	 */
	private static function get_ajax_action(): string {
		$action = filter_input( INPUT_POST, 'action', FILTER_SANITIZE_FULL_SPECIAL_CHARS );
		if ( ! $action ) {
			$action = filter_input( INPUT_GET, 'action', FILTER_SANITIZE_FULL_SPECIAL_CHARS );
		}

		if ( ! is_string( $action ) || '' === $action ) {
			return '';
		}

		return sanitize_key( $action );
	}
}