mall/utils/RandDiscount.php

<?php

namespace app\utils;

use app\models\Option;

class RandDiscount
{
    // 获取随机立减配置
    public static function getOption($store_id, $total_price)
    {
        $option = Option::get('rand_discount_option', $store_id, 'saas', json_encode([
            'is_open' => false,
            'start' => 0,
            'end' => 0.01,
        ]))['value'];

        $option = \json_decode($option);
        if ($option->start >= $total_price) {
            return [
                'is_open' => false,
                'rand' => 0,
            ];
        }
        $end = $option->end;
        if ($end >= $total_price) {
            $end = $total_price - 0.01;
        }
        $rand = static::randomFloat($option->start, $end);
        return [
            'is_open' => $option->is_open,
            'rand' => $rand,
        ];
    }

    public static function randomFloat($min = 0, $max = 0.01)
    {
        $num = $min + \mt_rand() / \mt_getrandmax() * ($max - $min);
        return \sprintf("%.2f", $num);
    }
}