<?php
/**
 * Core: Registers the product type, constants, and utility methods.
 */
defined('ABSPATH') || exit;

class Yoone_Product_Bundles {
    const TYPE = 'yoone_bundle';

    // Post meta keys for configuration
    const META_ALLOWED_PRODUCTS = '_yoone_bundle_allowed_products'; // array<int>
    const META_MIN_QTY          = '_yoone_bundle_min_quantity';     // int
    const META_CATEGORIES       = '_yoone_bundle_categories';       // array<int> product_cat term_ids

    protected static $instance = null;

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

    private function __construct() {
        // Add "Mix and Match" to the "Product Type" dropdown in the admin.
        add_filter('product_type_selector', array($this, 'register_product_type_in_selector'));
        // Map the type to our class name, so WooCommerce instantiates the correct product object.
        add_filter('woocommerce_product_class', array($this, 'map_product_class'), 10, 2);
    }

    /**
     * Add "Mix and Match" to the "Product Type" dropdown in the admin.
     */
    public function register_product_type_in_selector($types) {
        $types[self::TYPE] = __('Mix and Match (Yoone Bundle)', 'yoone-product-bundles');
        return $types;
    }

    /**
     * Map the type to our class name, so WooCommerce instantiates the correct product object.
     */
    public function map_product_class($classname, $product_type) {
        if ($product_type === self::TYPE) {
            $classname = 'WC_Product_Yoone_Bundle';
        }
        return $classname;
    }

    /**
     * Read and normalize the bundle configuration.
     * @param int|WC_Product $product
     * @return array{allowed_products:int[],min_qty:int,categories:int[]}
     */
    public static function get_bundle_config($product) {
        $product = is_numeric($product) ? wc_get_product($product) : $product;
        if (! $product) return array('allowed_products' => array(), 'min_qty' => 0, 'categories' => array());
        $pid = $product->get_id();
        $allowed = get_post_meta($pid, self::META_ALLOWED_PRODUCTS, true);
        $min     = absint(get_post_meta($pid, self::META_MIN_QTY, true));
        $cats    = get_post_meta($pid, self::META_CATEGORIES, true);
        // Keep only simple products (to avoid issues if variations or other types were selected in the backend)
        $allowed = is_array($allowed) ? array_values(array_map('absint', $allowed)) : array();
        if (! empty($allowed)) {
            $simple_only = array();
            foreach ($allowed as $aid) {
                $p = wc_get_product($aid);
                if ($p && $p->is_type('simple')) {
                    $simple_only[] = $aid;
                }
            }
            $allowed = $simple_only;
        }
        $cats    = is_array($cats) ? array_values(array_map('absint', $cats)) : array();
        return array(
            'allowed_products' => $allowed,
            'min_qty'          => max(0, $min),
            'categories'       => $cats,
        );
    }
}