<?php
/**
 * Access control for exclusive products.
 *
 * @package AISP_User_Exclusive_Products
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( 'AISP_Exclusive_Products_Access_Control' ) ) :

final class AISP_Exclusive_Products_Access_Control {

	private static $instance = null;

	public static function instance() {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	private function __construct() {

		// Block direct access to restricted single products.
		add_action( 'template_redirect', array( $this, 'block_single_product' ), 9 );

		// Make restricted products non-purchasable.
		add_filter( 'woocommerce_is_purchasable', array( $this, 'is_purchasable' ), 10, 2 );
		add_filter( 'woocommerce_variation_is_purchasable', array( $this, 'is_purchasable' ), 10, 2 );
	}

	/**
	 * Check if current user can view a given product.
	 *
	 * @param int $product_id The product ID.
	 * @return bool
	 */
	public function current_user_can_view( $product_id ) {

		// Admin / shop manager always see everything.
		if ( current_user_can( 'manage_woocommerce' ) || current_user_can( 'administrator' ) ) {
			return true;
		}

		// Get list of allowed users.
		$allowed_users = aisp_exclusive_products_get_allowed_users( $product_id );

		// Public product if no restricted users assigned.
		if ( empty( $allowed_users ) ) {
			return true;
		}

		// Unlogged user cannot see a restricted product.
		$user_id = get_current_user_id();
		if ( ! $user_id ) {
			return false;
		}

		// Final check: Is user in allowed list?
		return in_array( (int) $user_id, $allowed_users, true );
	}

	/**
	 * Block access to restricted single product pages.
	 */
	public function block_single_product() {

		if ( ! is_product() ) {
			return;
		}

		$product_id = get_queried_object_id();
		if ( ! $product_id ) {
			return;
		}

		// Redirect unauthorized users to shop.
		if ( ! $this->current_user_can_view( $product_id ) ) {
			wp_safe_redirect( wc_get_page_permalink( 'shop' ) );
			exit;
		}
	}

	/**
	 * Restrict purchasability for restricted products.
	 *
	 * @param bool       $purchasable Current purchasable status.
	 * @param WC_Product $product     Product object.
	 * @return bool
	 */
	public function is_purchasable( $purchasable, $product ) {

		if ( ! $product ) {
			return $purchasable;
		}

		// Prevent adding restricted products to cart.
		if ( ! $this->current_user_can_view( $product->get_id() ) ) {
			return false;
		}

		return $purchasable;
	}
}

endif;