<?php

declare(strict_types=1);

namespace App\Support;

use App\Models\Currency;
use App\Services\LotterySettings;

/**
 * 信用占成盘额度（代理/玩家授信、已用）在库内按「主货币整数」存储；
 * 彩票下注、钱包 API 使用最小货币单位（minor）。本类负责二者换算。
 */
final class CreditAmountScale
{
    public static function minorUnitFactor(string $currencyCode): int
    {
        $code = strtoupper(trim($currencyCode));
        if ($code === '') {
            return (int) max(1, 10 ** LotterySettings::currencyDisplayDecimals());
        }

        $currency = Currency::query()->where('code', $code)->first();
        $decimals = $currency !== null
            ? (int) $currency->decimal_places
            : LotterySettings::currencyDisplayDecimals();

        return (int) max(1, 10 ** max(0, min(12, $decimals)));
    }

    public static function majorToMinor(int $major, string $currencyCode): int
    {
        $major = max(0, $major);

        return $major * self::minorUnitFactor($currencyCode);
    }

    /** 最小单位 → 主货币整数（四舍五入）。 */
    public static function minorToMajor(int $minor, string $currencyCode): int
    {
        $factor = self::minorUnitFactor($currencyCode);
        if ($factor <= 1) {
            return $minor;
        }

        if ($minor >= 0) {
            return intdiv($minor + intdiv($factor, 2), $factor);
        }

        return -intdiv(-$minor + intdiv($factor, 2), $factor);
    }
}