<?php

namespace StoreSuit;

defined( 'ABSPATH' ) || exit;
// phpcs:disable WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Messages are returned as JSON by Admin::ajax() and shown with textContent; HTML output escapes them where printed.
/** Additional fields for a NEW product only, inside the existing once/atomic create. */
final class ProductEntry {
    public static function opening( array $data ) : float {
        $qty = Store::quantity( $data['opening_stock'] ?? 0, true );
        if ( $qty && (float) wc_stock_amount( $qty ) !== (float) $qty ) {
            throw new \InvalidArgumentException(I18n::t( 'Enter the shelf stock as a whole number.' ));
        }
        if ( $qty && (!empty( $data['purchase_id'] ) || !empty( $data['count_id'] ) || ($data['stock_action'] ?? 'none') === 'receive') ) {
            throw new \InvalidArgumentException(I18n::t( 'Do not enter the same stock twice. Use either shelf stock or receiving/counting for these goods.' ));
        }
        // Goods with a price and a supplier are received on the day's purchase (EntryBills): they are not opening stock.
        $billed = false;
        if ( $qty ) {
            Store::require_cap( 'storesuit_approve' );
            if ( !$billed && empty( $data['confirm_opening'] ) ) {
                throw new \InvalidArgumentException(I18n::t( 'Confirm the physical shelf stock before saving.' ));
            }
        }
        return $qty;
    }

    public static function fields( \WC_Product $p, array $data ) : void {
        $sale = Store::text( $data, 'sale_price' );
        if ( $sale !== '' ) {
            $value = Store::amount( $sale );
            if ( $value <= 0 ) {
                throw new \InvalidArgumentException(I18n::t( 'The sale price must be above zero. Leave it blank when there is no sale.' ));
            }
            if ( $value >= (float) $p->get_regular_price( 'edit' ) ) {
                throw new \InvalidArgumentException(I18n::t( 'The sale price must be lower than the regular price. Leave it blank when there is no sale.' ));
            }
            $p->set_sale_price( $value );
        }
        $image = absint( $data['image_id'] ?? 0 );
        if ( $image ) {
            Store::require_cap( 'upload_files' );
            if ( get_post_type( $image ) !== 'attachment' || !wp_attachment_is_image( $image ) || !current_user_can( 'edit_post', $image ) ) {
                throw new \InvalidArgumentException(I18n::t( 'Choose an image from your media library.' ));
            }
            $p->set_image_id( $image );
        }
        $barcode = Store::text( $data, 'barcode' );
        // Only a real GTIN also becomes WooCommerce's GTIN (the Google feed publishes it); every other code, a POS or shelf code
        // or an ISBN-10, stays in the barcode field only (0.62 review).
        $digits = str_replace( '-', '', $barcode );
        if ( $barcode !== '' && self::gtin( $digits ) && method_exists( $p, 'set_global_unique_id' ) ) {
            if ( function_exists( 'wc_get_product_id_by_global_unique_id' ) && wc_get_product_id_by_global_unique_id( $digits ) ) {
                throw new \InvalidArgumentException(I18n::t( 'This GTIN is already used by another product.' ));
            }
            $p->set_global_unique_id( $digits );
        }
    }

    /** The barcode as a GTIN (digits only) when it is a valid one, otherwise ''. */
    public static function as_gtin( string $barcode ) : string {
        $digits = str_replace( '-', '', $barcode );
        return ( $barcode !== '' && self::gtin( $digits ) ? $digits : '' );
    }

    /** A GTIN-8, -12, -13 or -14 with a correct check digit, outside the ranges shops number their own goods with. */
    private static function gtin( string $digits ) : bool {
        if ( !preg_match( '/^(?:\\d{8}|\\d{12,14})$/D', $digits ) ) {
            return false;
        }
        $len = strlen( $digits );
        if ( $len === 13 && $digits[0] === '2' || $len === 12 && in_array( $digits[0], array('2', '4'), true ) || $len === 8 && in_array( $digits[0], array('0', '2'), true ) || $len === 14 && $digits[1] === '2' ) {
            return false;
        }
        $sum = 0;
        for ($i = $len - 2, $w = 3; $i >= 0; $i--, $w = 4 - $w) {
            $sum += (int) $digits[$i] * $w;
        }
        return (10 - $sum % 10) % 10 === (int) $digits[$len - 1];
    }

    public static function log( \WC_Product $p, float $qty ) : void {
        if ( !$qty ) {
            return;
        }
    }

}