<?php

namespace App\Services;

use App\Http\helper\NumConfig;
use App\Models\RecordScoreInfo;
use App\Models\UserCoupon;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;

/**
 * 优惠券服务
 *
 * 职责:
 *   1. 自动发放优惠券（根据配置策略）
 *   2. 获取用户可用优惠券列表
 *   3. 使用优惠券（充值成功后：增加金币 + 标记已用）
 */
class CouponService
{
    /** @var int 优惠券赠送金币的原因码 */
    const SCORE_REASON = 55;

    /**
     * 获取用户可用优惠券列表，同时触发自动发放逻辑
     *
     * @param int $userId
     * @return array  ['list' => [...], 'new_issued' => [...]]
     */
    public function getCouponList($userId)
    {
        // 1. 先清理已过期的优惠券
        UserCoupon::expireByUser($userId);

        // 2. 自动发放符合条件的优惠券
        $newIssued = $this->autoIssue($userId);

        // 3. 返回当前可用列表
        $list = UserCoupon::getAvailableList($userId);

        return [
            'list'       => $list,
            'new_issued' => $newIssued,
        ];
    }

    /**
     * 自动发放优惠券（根据 config/coupon.php 中的 auto_issue_rules）
     *
     * 发放逻辑:
     *   - 遍历所有规则
     *   - 检查用户是否满足发放条件
     *   - 检查用户是否已持有同名有效券（防重复）
     *   - 满足条件则发放
     *
     * @param int $userId
     * @return array 本次新发放的优惠券列表
     */
    public function autoIssue($userId)
    {
        $rules = config('coupon.auto_issue_rules', []);
        $enabled = config('coupon.enabled_rules', []);
        $allEnabled = in_array('*', $enabled, true);
        $newIssued = [];

        foreach ($rules as $rule) {
            // 仅处理当前生效的规则（'*' 表示全部生效）
            if (!$allEnabled && !in_array($rule['coupon_name'], $enabled, true)) {
                continue;
            }

            // 防重复：已持有同名有效券则跳过
            if (UserCoupon::hasSameCoupon($userId, $rule['coupon_name'])) {
                continue;
            }

            // 检查发放条件
            if (!$this->checkCondition($userId, $rule['condition'])) {
                continue;
            }

            // 发放优惠券
            $now = date('Y-m-d H:i:s');
            $couponData = [
                'user_id'      => $userId,
                'coupon_name'  => $rule['coupon_name'],
                'coupon_type'  => $rule['coupon_type'],
                'coupon_value' => $rule['coupon_value'],
                'min_recharge' => $rule['min_recharge'] ?? 0,
                'max_bonus'    => $rule['max_bonus'] ?? 0,
                'bonus_coins'  => 0,
                'order_sn'     => '',
                'status'       => UserCoupon::STATUS_UNUSED,
                'issued_at'    => $now,
                'used_at'      => null,
                'expire_at'    => date('Y-m-d H:i:s', strtotime("+{$rule['valid_days']} days")),
            ];

            try {
                $id = UserCoupon::issueToUser($couponData);
                $couponData['id'] = $id;
                $newIssued[] = $couponData;

                Log::info('Coupon auto-issued', [
                    'user_id'     => $userId,
                    'coupon_name' => $rule['coupon_name'],
                    'coupon_id'   => $id,
                ]);
            } catch (\Exception $e) {
                Log::error('Coupon auto-issue failed', [
                    'user_id'     => $userId,
                    'coupon_name' => $rule['coupon_name'],
                    'error'       => $e->getMessage(),
                ]);
            }
        }

        return $newIssued;
    }

    /**
     * 检查用户是否满足发放条件
     *
     * @param int   $userId
     * @param array $condition  ['type' => '...', '...' => ...]
     * @return bool
     */
    protected function checkCondition($userId, array $condition)
    {
        $type = $condition['type'] ?? '';

        switch ($type) {

            // 新人条件：注册天数 <= N 且无充值记录
            case 'new_user':
                $days = $condition['days'] ?? 3;
                return $this->isNewUser($userId, $days);

            // 累计充值 >= N 元
            case 'recharge_total':
                $amount = $condition['amount'] ?? 0;
                return $this->hasRechargeTotal($userId, $amount);

            // 最近充值距今 >= N 天（且有过充值记录）
            case 'inactive_days':
                $days = $condition['days'] ?? 7;
                return $this->isInactive($userId, $days);

            // VIP 等级 >= N
            case 'vip_level':
                $level = $condition['level'] ?? 1;
                return $this->hasVipLevel($userId, $level);

            default:
                Log::warning('Unknown coupon condition type', ['type' => $type]);
                return false;
        }
    }

    /**
     * 判断是否为新用户：注册天数 <= N 且无充值记录
     *
     * @param int $userId
     * @param int $days 注册天数阈值
     * @return bool
     */
    protected function isNewUser($userId, $days)
    {
        $user = DB::connection('write')->table('QPAccountsDB.dbo.AccountsInfo')
            ->where('UserID', $userId)
            ->select('RegisterDate')
            ->first();

        if (!$user || !$user->RegisterDate) {
            return false;
        }

        // 注册天数 <= 阈值
        $registerDate = strtotime($user->RegisterDate);
        $diffDays = (time() - $registerDate) / 86400;
        if ($diffDays > $days) {
            return false;
        }

        // 无充值记录
        $hasRecharge = DB::connection('write')->table('agent.dbo.order')
            ->where('user_id', $userId)
            ->where('pay_status', 1)
            ->exists();

        return !$hasRecharge;
    }

    /**
     * 判断累计充值是否达到阈值
     *
     * @param int   $userId
     * @param float $amount 阈值（元）
     * @return bool
     */
    protected function hasRechargeTotal($userId, $amount)
    {
        $total = DB::connection('write')->table('QPAccountsDB.dbo.YN_VIPAccount')
            ->where('UserID', $userId)
            ->value('Recharge');

        return ($total ?? 0) >= $amount;
    }

    /**
     * 判断用户是否处于不活跃状态：最近一次充值距今 >= N 天
     * 前提：用户至少有过一次充值记录
     *
     * @param int $userId
     * @param int $days
     * @return bool
     */
    protected function isInactive($userId, $days)
    {
        $lastRecharge = DB::connection('write')->table('agent.dbo.order')
            ->where('user_id', $userId)
            ->where('pay_status', 1)
            ->max('pay_at');

        if (!$lastRecharge) {
            return false; // 从未充值，不适用"回归"逻辑
        }

        $lastTime = strtotime($lastRecharge);
        $diffDays = (time() - $lastTime) / 86400;

        return $diffDays >= $days;
    }

    /**
     * 判断 VIP 等级是否达到阈值
     *
     * @param int $userId
     * @param int $level
     * @return bool
     */
    protected function hasVipLevel($userId, $level)
    {
        // 使用 VipService 获取用户当前VIP等级
        $userRecharge = DB::connection('write')->table('QPAccountsDB.dbo.YN_VIPAccount')
            ->where('UserID', $userId)
            ->value('Recharge') ?? 0;

        $vipLevel = VipService::calculateVipLevel($userId, $userRecharge);

        return $vipLevel >= $level;
    }

    /**
     * 验证优惠券是否可用于本次充值
     *
     * @param int   $couponId
     * @param int   $userId
     * @param float $payAmt 充值金额（元）
     * @return array  ['valid' => bool, 'coupon' => object|null, 'error' => string]
     */
    public function validateCoupon($couponId, $userId, $payAmt)
    {
        $coupon = UserCoupon::getUserCouponById($couponId, $userId);

        if (!$coupon) {
            return ['valid' => false, 'coupon' => null, 'error' => 'Coupon not found'];
        }

        if ($coupon->status != UserCoupon::STATUS_UNUSED) {
            return ['valid' => false, 'coupon' => $coupon, 'error' => 'Coupon already used or expired'];
        }

        if (strtotime($coupon->expire_at) < time()) {
            return ['valid' => false, 'coupon' => $coupon, 'error' => 'Coupon expired'];
        }

        if ($payAmt < $coupon->min_recharge) {
            return [
                'valid'  => false,
                'coupon' => $coupon,
                'error'  => "Minimum recharge {$coupon->min_recharge} required for this coupon",
            ];
        }

        return ['valid' => true, 'coupon' => $coupon, 'error' => ''];
    }

    /**
     * 计算优惠券赠送的金币数（单位：分）
     *
     * @param object $coupon 优惠券记录
     * @param float  $payAmt 充值金额（元）
     * @return int 赠送金币数（分）
     */
    public function calcBonusCoins($coupon, $payAmt)
    {
        if ($coupon->coupon_type == UserCoupon::TYPE_FIXED) {
            // 固定金额
            $bonusYuan = $coupon->coupon_value;
        } else {
            // 百分比：赠送金额 = 充值金额 * 百分比
            $bonusYuan = $payAmt * ($coupon->coupon_value / 100);

            // 上限限制
            if ($coupon->max_bonus > 0 && $bonusYuan > $coupon->max_bonus) {
                $bonusYuan = $coupon->max_bonus;
            }
        }

        // 转换为分（1元 = 100分）
        return (int) round($bonusYuan * NumConfig::NUM_VALUE);
    }

    /**
     * 使用优惠券：标记已用 + 发放金币
     *
     * 在充值回调中调用此方法。
     *
     * @param int    $couponId
     * @param int    $userId
     * @param float  $payAmt 充值金额（元）
     * @param string $orderSn
     * @return array  ['success' => bool, 'bonus_coins' => int, 'error' => string]
     */
    public function useCoupon($couponId, $userId, $payAmt, $orderSn)
    {
        // 验证
        $validation = $this->validateCoupon($couponId, $userId, $payAmt);
        if (!$validation['valid']) {
            return ['success' => false, 'bonus_coins' => 0, 'error' => $validation['error']];
        }

        $coupon = $validation['coupon'];

        // 计算赠送金币
        $bonusCoins = $this->calcBonusCoins($coupon, $payAmt);

        if ($bonusCoins <= 0) {
            return ['success' => false, 'bonus_coins' => 0, 'error' => 'Bonus amount is zero'];
        }

        // 标记优惠券已使用（乐观锁：status=unused 才更新）
        $marked = UserCoupon::markUsed($coupon->id, $orderSn, $bonusCoins);
        if (!$marked) {
            return ['success' => false, 'bonus_coins' => 0, 'error' => 'Coupon already used'];
        }

        // 发放金币到用户账户
        try {
            $reason = config('coupon.score_reason', self::SCORE_REASON);
            RecordScoreInfo::addScore($userId, $bonusCoins, $reason);

            // 实际增加 GameScoreInfo.Score
            DB::connection('write')->table('QPTreasureDB.dbo.GameScoreInfo')
                ->where('UserID', $userId)
                ->increment('Score', $bonusCoins);

            Log::info('Coupon bonus coins added', [
                'user_id'     => $userId,
                'coupon_id'   => $coupon->id,
                'order_sn'    => $orderSn,
                'bonus_coins' => $bonusCoins,
                'pay_amt'     => $payAmt,
            ]);

            return ['success' => true, 'bonus_coins' => $bonusCoins, 'error' => ''];
        } catch (\Exception $e) {
            Log::error('Coupon add coins failed', [
                'user_id'     => $userId,
                'coupon_id'   => $coupon->id,
                'error'       => $e->getMessage(),
            ]);

            return ['success' => false, 'bonus_coins' => 0, 'error' => 'Failed to add bonus coins'];
        }
    }
}