<?php
namespace Clusterlane\Core;

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

/**
 * Shop (0.98.172) — WooCommerce products as Clusterlane content.
 *
 * Nothing here does anything unless WooCommerce is active. With it:
 *   - product categories (product_cat) can be chosen as clusters in Cluster
 *     Admin, which also adds products to the scanned post types;
 *   - products hidden from the shop (visibility "Search results only" or
 *     "Hidden", i.e. the product_visibility term exclude-from-catalog) are
 *     out of scope everywhere: no scores, no cluster membership, never a
 *     link target — through Scope, like password-protected posts;
 *   - variations (product_variation) are never scanned: they have no page;
 *   - products get their own score (Scanner): a good product page is a clear
 *     description, a short description and images, and articles linking to
 *     it — not 800 words with H2 headings or links out.
 *
 * WooCommerce keeps a product's long description in post_content and its
 * short description in post_excerpt; both are read as the product's text.
 */
final class Shop {

    public const TYPE     = 'product';
    public const TAXONOMY = 'product_cat';

    public static function active(): bool {
        return class_exists( 'WooCommerce' ) && post_type_exists( self::TYPE ) && taxonomy_exists( self::TAXONOMY );
    }

    public static function is_product( ?\WP_Post $post ): bool {
        return $post && $post->post_type === self::TYPE && self::active();
    }

    /** Products are among the scanned post types (Cluster Admin adds them when a product category is chosen). */
    public static function in_scope(): bool {
        return self::active() && in_array( self::TYPE, Scope::post_types(), true );
    }

    /** True when WooCommerce keeps this product out of the shop's catalogue. */
    public static function hidden( int $post_id ): bool {
        return self::active() && has_term( 'exclude-from-catalog', 'product_visibility', $post_id );
    }

    /**
     * SQL (starting with " AND ") that leaves hidden products out, for a posts
     * table alias ('' = the posts table by its own name). '' when not a shop.
     */
    public static function hidden_sql( string $alias = '' ): string {
        if ( ! self::in_scope() ) return '';
        global $wpdb;
        $a = $alias !== '' ? $alias : $wpdb->posts;
        return " AND NOT ( {$a}.post_type = 'product' AND EXISTS ( SELECT 1 FROM {$wpdb->term_relationships} shtr
            INNER JOIN {$wpdb->term_taxonomy} shtt ON shtt.term_taxonomy_id = shtr.term_taxonomy_id AND shtt.taxonomy = 'product_visibility'
            INNER JOIN {$wpdb->terms} sht ON sht.term_id = shtt.term_id AND sht.slug = 'exclude-from-catalog'
            WHERE shtr.object_id = {$a}.ID ) )";
    }

    /** Short description (post_excerpt) of a product, as plain text. */
    public static function short_description( \WP_Post $post ): string {
        return trim( wp_strip_all_tags( (string) $post->post_excerpt ) );
    }

    /** Images in a product's gallery (_product_image_gallery), not counting the main image. */
    public static function gallery_count( int $post_id ): int {
        $g = (string) get_post_meta( $post_id, '_product_image_gallery', true );
        return $g === '' ? 0 : count( array_filter( explode( ',', $g ) ) );
    }
}