<?php

namespace App\Services;

use App\Exceptions\BizException;
use App\Models\ShippingRule;

class ShippingService
{
    /**
     * 运费模板根据地址，重量, 商品金额 计算运费; 重量传g，金额传分
     *
     * @param integer $weight
     * @param integer $templateId
     * @return void
     */
    public function countShippingAmount(int $weight, int $totalAmount, int $templateId, int $zoneId)
    {
        $shipping_amount = 0;
        //获取运费规则；
        $rules = ShippingRule::with('zones')->where('template_id', $templateId)->get();
        $canShipping = true;//是否支持寄送
        //如果该模板下无运费规则，则直接包邮
        if ($rules->count() > 0) {
            //按包邮/计重
            $rules = $rules->sortBy('type');//优先计算包邮
            foreach ($rules as $rule) {
                $canShipping = false;
                $_ruleInfo = json_decode($rule->info, true);

                if (in_array($zoneId, $rule->zones->pluck('id')->toArray())) {
                    $canShipping = true;
                    if ($rule->type == ShippingRule::TYPE_FREE) {
                        if ($totalAmount >= bcmul($_ruleInfo['threshold'], 100)) {//在包邮价格范围内
                            break;//跳出foreach循环, 直接包邮
                        }
                    } elseif ($rule->type == ShippingRule::TYPE_WEIGHT) {
                        $_firstWeight = (int) bcmul($_ruleInfo['first_weight'], 1000);
                        $_firstWamount = (int) bcmul($_ruleInfo['first_w_amount'], 100);
                        $_contiueWeight = (int) bcmul($_ruleInfo['continue_weight'], 1000);
                        $_contiueWamount = (int) bcmul($_ruleInfo['continue_w_amount'], 100);
                        if ($weight <= $_firstWeight) {
                            $shipping_amount = $_firstWamount;
                            break;
                        } else {//计算续重价格
                            $num = (int) bcdiv(($weight - $_firstWeight), $_contiueWeight);
                            $shipping_amount = (int) bcadd($_firstWamount, bcmul($num+1, $_contiueWamount));
                            break;
                        }
                    }
                }
            }
        }
        if (!$canShipping) {
            throw new BizException('当前选择的地址有部分商品不支持配送');
        }

        return $this->returnAmount($shipping_amount);
    }

    /**
     * 统一返回运费格式
     *
     * @param [type] $shipping_amount
     * @return void
     */
    protected function returnAmount($shipping_amount)
    {
        return $shipping_amount;
        // return bcdiv($shipping_amount, 100, 2);
    }
}