<?php

namespace App\Services;

use App\Models\StoreOrderModel;

/**
 * 周转框/周转托盘数量修改（订单附加金额重算）
 */
readonly class StoreOrderContainerService
{
    /**
     * 更新订单周转框/托盘数量并重算附加金额与订单总金额。
     * 历史订单未写商品金额：按「总额 - 附加」反推并回写，保证 总额 = 商品 + 附加 恒成立。
     */
    public function update(StoreOrderModel $order, int $boxNum, int $trayNum): void
    {
        $boxPrice = (float) site_config('services.box_amount', 0);
        $trayPrice = (float) site_config('services.tray_amount', 0);
        $addedAmount = round($boxNum * $boxPrice + $trayNum * $trayPrice, 2);

        $productAmount = (float) $order->product_amount;
        if ($productAmount <= 0 && (float) $order->total_amount > 0) {
            $productAmount = round((float) $order->total_amount - (float) $order->added_amount, 2);
        }

        $order->box_num = $boxNum;
        $order->tray_num = $trayNum;
        $order->product_amount = $productAmount;
        $order->added_amount = $addedAmount;
        $order->total_amount = round($productAmount + $addedAmount, 2);
        $order->save();
    }
}