<?php
/**
 * Decides whether a product can be tried on.
 *
 * @package Fitzaro
 */

namespace Fitzaro\Api;

use Fitzaro\Prompt\TypeResolver;

defined( 'ABSPATH' ) || exit;

/**
 * Only published, public products of a supported type (top, dress, eyewear) with an image. Per-product and per-category switches come with
 * the admin screens.
 */
final class ProductCheck {

	public const NOT_FOUND          = 'not_found';
	public const NOT_PUBLIC         = 'not_public';
	public const NO_IMAGE           = 'no_image';
	public const VARIATION_MISMATCH = 'variation_mismatch';
	public const UNSUPPORTED_TYPE   = 'unsupported_type';

	/**
	 * Null when try-on is allowed, otherwise one of the constants above.
	 *
	 * @param int $product_id   Product.
	 * @param int $variation_id Variation, 0 for none.
	 */
	public static function problem( int $product_id, int $variation_id ): ?string {
		$product = wc_get_product( $product_id );
		if ( ! $product instanceof \WC_Product || $product->is_type( 'variation' ) ) {
			return self::NOT_FOUND;
		}

		if ( 'publish' !== $product->get_status() || post_password_required( $product_id ) ) {
			return self::NOT_PUBLIC;
		}

		if ( null === TypeResolver::for_product( $product_id ) ) {
			return self::UNSUPPORTED_TYPE;
		}

		$shown = $product;
		if ( $variation_id > 0 ) {
			$variation = wc_get_product( $variation_id );
			if ( ! $variation instanceof \WC_Product_Variation || $variation->get_parent_id() !== $product_id ) {
				return self::VARIATION_MISMATCH;
			}
			$shown = $variation;
		}

		return $shown->get_image_id() ? null : self::NO_IMAGE;
	}
}