<?php

declare( strict_types=1 );

namespace Automattic\WooCommerce\Internal\Utilities;

use Automattic\WooCommerce\Caches\ProductCountCache;

/**
 * Class with general utility methods related to products.
 */
class ProductUtil {
	/**
	 * Transient name for the cached dashboard "out of stock" product count.
	 *
	 * Exposed as a constant so the one-time DB update that clears this transient
	 * (wc_update_1110_delete_dashboard_outofstock_count_transient) stays in sync
	 * with the runtime invalidation list below.
	 *
	 * @since 11.1.0
	 *
	 * @var string
	 */
	public const OUTOFSTOCK_COUNT_TRANSIENT = 'wc_outofstock_count';

	/**
	 * Name prefixes of the transients kept for each product, followed by the product ID.
	 *
	 * Exposed as a constant so the "Clear transients" tool, which deletes these transients for
	 * every product, stays in sync with the per-product invalidation below.
	 *
	 * @since 11.3.0
	 *
	 * @var string[]
	 */
	public const PRODUCT_SPECIFIC_TRANSIENT_PREFIXES = array(
		'wc_product_children_',
		'wc_var_prices_',
		'wc_related_',
		'wc_child_has_weight_',
		'wc_child_has_dimensions_',
	);

	/**
	 * Get a product ID from a product, post, or numeric value.
	 *
	 * @since 11.3.0
	 *
	 * @param mixed $product Product instance, post instance, or numeric ID.
	 * @return int Product ID, or 0 when no ID is available.
	 */
	public function get_product_id( $product ): int {
		if ( is_numeric( $product ) ) {
			return (int) $product;
		} elseif ( $product instanceof \WC_Product ) {
			return (int) $product->get_id();
		} elseif ( is_object( $product ) && ! empty( $product->ID ) ) {
			return (int) $product->ID;
		} else {
			return 0;
		}
	}

	/**
	 * Delete all product transients for a set of products.
	 *
	 * Fixed-name transients are deleted once for the whole set, and the
	 * woocommerce_delete_product_transients action fires once per product ID.
	 *
	 * @param array $product_ids Product IDs whose transients are being deleted.
	 * @return void
	 */
	public function delete_product_transients_for_products( array $product_ids ): void {
		$product_ids = array_unique( array_map( 'absint', $product_ids ) );

		// Transient data to clear with a fixed name which may be stale after product updates.
		$transients_to_clear = array(
			'wc_products_onsale',
			'wc_featured_products',
			self::OUTOFSTOCK_COUNT_TRANSIENT,
			'wc_low_stock_count',
		);

		foreach ( $transients_to_clear as $transient ) {
			delete_transient( $transient );
		}

		$product_ids_to_clear = array_filter( $product_ids );
		if ( ! empty( $product_ids_to_clear ) ) {
			$this->delete_product_specific_transients_for_products( $product_ids_to_clear );
		}

		// Kept for compatibility, WooCommerce core doesn't use product transient versions anymore.
		\WC_Cache_Helper::get_transient_version( 'product', true );
		\WC_Cache_Helper::get_transient_version( 'product_query', true );

		foreach ( $product_ids as $product_id ) {
			/**
			 * Fires after product transients are deleted.
			 *
			 * @since 2.3.0
			 *
			 * @param int $product_id Product ID whose transients were deleted.
			 */
			do_action( 'woocommerce_delete_product_transients', $product_id );
		}
	}

	/**
	 * Delete the transients related to a specific product.
	 * If the product is a variation, delete the transients for the parent too.
	 *
	 * @param \WC_Product|int $product_or_id The product or the product id.
	 * @return void
	 */
	public function delete_product_specific_transients( $product_or_id ) {
		$this->delete_product_specific_transients_for_products( array( $product_or_id ) );
	}

	/**
	 * Delete the transients related to a set of products.
	 * If a product is a variation, delete the transients for the parent too.
	 *
	 * @param array $products_or_ids Products or product ids.
	 * @return void
	 */
	public function delete_product_specific_transients_for_products( array $products_or_ids ) {
		$product_ids = array();

		foreach ( $products_or_ids as $product_or_id ) {
			$parent_id = 0;
			if ( $product_or_id instanceof \WC_Product ) {
				$product    = $product_or_id;
				$product_id = $product->get_id();
			} else {
				$product_id = $product_or_id;
				$product    = wc_get_product( $product_id );
			}

			if ( $product instanceof \WC_Product_Variation ) {
				$parent_id = $product->get_parent_id();
			}

			$product_ids[] = $product_id;
			if ( $parent_id ) {
				$product_ids[] = $parent_id;
			}
		}

		$product_ids = array_unique( array_filter( array_map( 'absint', $product_ids ) ) );

		foreach ( $product_ids as $product_id ) {
			foreach ( self::PRODUCT_SPECIFIC_TRANSIENT_PREFIXES as $transient ) {
				delete_transient( $transient . $product_id );
			}
		}
	}

	/**
	 * Prime featured and gallery image attachment caches for a collection of products in a single
	 * batched query, instead of priming each product's images separately.
	 *
	 * @param array $products Products whose image attachments should be primed. Non-product items are ignored.
	 * @return void
	 */
	public function prime_image_caches( array $products ): void {
		$products  = array_filter( $products, static fn( $product ) => $product instanceof \WC_Product );
		$featured  = array_map( static fn( $product ) => $product->get_image_id(), $products );
		$gallery   = array_map( static fn( $product ) => $product->get_gallery_image_ids(), $products );
		$image_ids = array_filter( array_unique( array_map( 'intval', array_merge( $featured, ...$gallery ) ) ) );
		if ( ! empty( $image_ids ) ) {
			// Prime caches to reduce future queries.
			_prime_post_caches( $image_ids );
		}
	}

	/**
	 * Append the product meta lookup join unless the clause mentions wc_product_meta_lookup as a standalone token.
	 * References, SQL literals and comments also count as mentions; this is not an SQL parser.
	 *
	 * @since 11.2.0
	 *
	 * @param mixed $join SQL JOIN clause supplied by query filters.
	 * @return string
	 */
	public function append_product_sorting_table_join( $join ): string {
		global $wpdb;

		// Preserve stringable clauses: discarding a join can break a WHERE clause that still references it.
		if ( ! is_string( $join ) ) {
			$stringable = is_object( $join ) && method_exists( $join, '__toString' );
			$join       = $stringable ? (string) $join : '';
		}

		// A non-empty wpdb prefix prevents a table-name match. Empty prefixes retain the old guard's limitation.
		if ( ! preg_match( '/\bwc_product_meta_lookup\b/', $join ) ) {
			$join .= " LEFT JOIN {$wpdb->wc_product_meta_lookup} wc_product_meta_lookup ON $wpdb->posts.ID = wc_product_meta_lookup.product_id ";
		}
		return $join;
	}

	/**
	 * Counts per-status number of products of a given post type.
	 *
	 * @since 11.0.0
	 *
	 * @param string $post_type Post type (e.g. 'product', 'product_variation').
	 * @return array<string|int,int>
	 */
	public function get_counts_for_type( string $post_type ): array {
		$product_count_cache = wc_get_container()->get( ProductCountCache::class );
		$count_per_status    = $product_count_cache->get( $post_type );

		if ( null === $count_per_status ) {
			// Defensive perimeter: dirty product data (running/crushed product data import/migration/mocking utilities).
			// We passed on adding wc_doing_it_wrong as it'll add asymmetric friction to already running customers fleet.
			// Enforce strict typing to prevent PHP from silently casting numeric-string array keys to integers, and to normalize inconsistent types from WordPress APIs.
			$count_per_status = (array) wp_count_posts( $post_type ) + array_fill_keys( array_keys( get_post_stati() ), 0 );
			foreach ( $count_per_status as $status => $count ) {
				$product_count_cache->set( $post_type, (string) $status, (int) $count );
			}
		}

		return array_map( 'intval', $count_per_status );
	}
}