<?php

namespace App\Services;

use App\Constants\HttpStatus;
use App\Models\Backflow;
use App\Models\Config;
use App\Models\Rebate;
use App\Models\Wallet;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;
use RuntimeException;

/** Shared transaction for manual and automatic payouts. Never trusts a previously loaded reward row. */
class RewardGrantService
{
    public static function grant(string $type, int $id, string $operator, bool $skipPaid = false, ?string $scheduledCutoff = null): bool
    {
        if (!in_array($type, RewardGrantSettingsService::TYPES, true)) {
            throw new RuntimeException('奖励类型错误', HttpStatus::CUSTOM_ERROR);
        }

        return DB::transaction(function () use ($type, $id, $operator, $skipPaid, $scheduledCutoff) {
            $model = $type === 'rebate' ? Rebate::class : Backflow::class;
            $reward = $model::whereKey($id)->lockForUpdate()->first();
            if (!$reward) throw new RuntimeException('数据不存在', HttpStatus::CUSTOM_ERROR);
            if ((int) $reward->status !== 0) {
                if ($skipPaid) return false;
                throw new RuntimeException('奖励已发放，无需再次发放', HttpStatus::CUSTOM_ERROR);
            }
            $cutoff = $type === 'rebate'
                ? Carbon::now('America/New_York')->format('Y-m-d')
                : Carbon::now('Asia/Shanghai')->format('Y-m');
            if ((string) $reward->date >= $cutoff) {
                throw new RuntimeException('未到发放时间', HttpStatus::CUSTOM_ERROR);
            }
            if ($scheduledCutoff !== null && (string) $reward->date >= $scheduledCutoff) return false;

            if ($type === 'rebate') {
                $ratio = self::configDecimal('rebate');
                $basis = (string) $reward->effective_betting_amount;
                if (bccomp($basis, '0', 2) < 0) throw new RuntimeException('有效投注金额异常', HttpStatus::CUSTOM_ERROR);
                $amount = bcmul($basis, $ratio, 2);
                $reward->rebate_ratio = $ratio;
                $reward->audited_by = $operator;
                $changeType = '笔笔返';
                $remark = "日期:{$reward->date};有效投注:{$basis}；比例:" . bcmul($ratio, '100', 2) . '%';
            } else {
                // Preserve the existing monthly formula: abs(recharge + signed withdrawal).
                $basis = bcadd((string) $reward->recharge_amount, (string) $reward->withdrawal_amount, 2);
                if (bccomp($basis, '0', 2) < 0) $basis = bcsub('0', $basis, 2);
                $amount = '0.00';
                $ratio = (string) $reward->backflow_ratio;
                if (bccomp($basis, self::configDecimal('huishui_restriction'), 2) >= 0) {
                    $ratio = self::configDecimal('huishui_percentage');
                    $reward->backflow_ratio = $ratio;
                    $amount = bcmul($basis, $ratio, 2);
                }
                $changeType = '回水';
                $remark = "日期:{$reward->date};盈亏:-{$basis}；回水比例:" . bcmul($ratio ?: '0', '100', 2) . '%';
            }

            if (bccomp($amount, '0', 2) > 0) {
                $wallet = Wallet::where('member_id', $reward->member_id)->lockForUpdate()->first();
                if (!$wallet) throw new RuntimeException('会员钱包不存在', HttpStatus::CUSTOM_ERROR);
                $before = (string) $wallet->available_balance;
                $wallet->available_balance = bcadd($before, $amount, 10);
                if (!$wallet->save()) throw new RuntimeException('余额更新失败', HttpStatus::CUSTOM_ERROR);
                BalanceLogService::addLog($reward->member_id, $amount, $before, $wallet->available_balance,
                    $changeType, $reward->id, $remark);
            }
            $reward->amount = $amount;
            $reward->status = 1;
            $reward->grant_time = Carbon::now()->timestamp;
            if (!$reward->save()) throw new RuntimeException('发放失败', HttpStatus::CUSTOM_ERROR);
            return true;
        }, 3);
    }

    private static function configDecimal(string $field): string
    {
        $value = trim((string) Config::where('field', $field)->value('val'));
        if (!preg_match('/^\d+(?:\.\d+)?$/D', $value)) {
            throw new RuntimeException('奖励比例或门槛配置异常', HttpStatus::CUSTOM_ERROR);
        }
        return $value;
    }
}