package services

import (
	"context"
	"fmt"
	"time"

	"github.com/google/uuid"
	"go.uber.org/zap"

	"tyapi-server/internal/config"
	"tyapi-server/internal/domains/user/entities"
	"tyapi-server/internal/domains/user/repositories"
	"tyapi-server/internal/shared/interfaces"
	"tyapi-server/internal/shared/sms"
)

// SMSCodeService 短信验证码服务
type SMSCodeService struct {
	repo      *repositories.SMSCodeRepository
	smsClient sms.Service
	cache     interfaces.CacheService
	config    config.SMSConfig
	logger    *zap.Logger
}

// NewSMSCodeService 创建短信验证码服务
func NewSMSCodeService(
	repo *repositories.SMSCodeRepository,
	smsClient sms.Service,
	cache interfaces.CacheService,
	config config.SMSConfig,
	logger *zap.Logger,
) *SMSCodeService {
	return &SMSCodeService{
		repo:      repo,
		smsClient: smsClient,
		cache:     cache,
		config:    config,
		logger:    logger,
	}
}

// SendCode 发送验证码
func (s *SMSCodeService) SendCode(ctx context.Context, phone string, scene entities.SMSScene, clientIP, userAgent string) error {
	// 检查频率限制
	if err := s.checkRateLimit(ctx, phone); err != nil {
		return err
	}

	// 生成验证码
	code := s.smsClient.GenerateCode(s.config.CodeLength)

	// 创建SMS验证码记录
	smsCode := &entities.SMSCode{
		ID:        uuid.New().String(),
		Phone:     phone,
		Code:      code,
		Scene:     scene,
		IP:        clientIP,
		UserAgent: userAgent,
		Used:      false,
		ExpiresAt: time.Now().Add(s.config.ExpireTime),
	}

	// 保存验证码
	if err := s.repo.Create(ctx, smsCode); err != nil {
		s.logger.Error("保存短信验证码失败",
			zap.String("phone", phone),
			zap.String("scene", string(scene)),
			zap.Error(err))
		return fmt.Errorf("保存验证码失败: %w", err)
	}

	// 发送短信
	if err := s.smsClient.SendVerificationCode(ctx, phone, code); err != nil {
		// 记录发送失败但不删除验证码记录，让其自然过期
		s.logger.Error("发送短信验证码失败",
			zap.String("phone", phone),
			zap.String("code", code),
			zap.Error(err))
		return fmt.Errorf("短信发送失败: %w", err)
	}

	// 更新发送记录缓存
	s.updateSendRecord(ctx, phone)

	s.logger.Info("短信验证码发送成功",
		zap.String("phone", phone),
		zap.String("scene", string(scene)))

	return nil
}

// VerifyCode 验证验证码
func (s *SMSCodeService) VerifyCode(ctx context.Context, phone, code string, scene entities.SMSScene) error {
	// 根据手机号和场景获取有效的验证码记录
	smsCode, err := s.repo.GetValidCode(ctx, phone, scene)
	if err != nil {
		return fmt.Errorf("验证码无效或已过期")
	}

	// 验证验证码是否匹配
	if smsCode.Code != code {
		return fmt.Errorf("验证码无效或已过期")
	}

	// 标记验证码为已使用
	if err := s.repo.MarkAsUsed(ctx, smsCode.ID); err != nil {
		s.logger.Error("标记验证码为已使用失败",
			zap.String("code_id", smsCode.ID),
			zap.Error(err))
		return fmt.Errorf("验证码状态更新失败")
	}

	s.logger.Info("短信验证码验证成功",
		zap.String("phone", phone),
		zap.String("scene", string(scene)))

	return nil
}

// checkRateLimit 检查发送频率限制
func (s *SMSCodeService) checkRateLimit(ctx context.Context, phone string) error {
	now := time.Now()

	// 检查最小发送间隔
	lastSentKey := fmt.Sprintf("sms:last_sent:%s", phone)
	var lastSent time.Time
	if err := s.cache.Get(ctx, lastSentKey, &lastSent); err == nil {
		if now.Sub(lastSent) < s.config.RateLimit.MinInterval {
			return fmt.Errorf("请等待 %v 后再试", s.config.RateLimit.MinInterval)
		}
	}

	// 检查每小时发送限制
	hourlyKey := fmt.Sprintf("sms:hourly:%s:%s", phone, now.Format("2006010215"))
	var hourlyCount int
	if err := s.cache.Get(ctx, hourlyKey, &hourlyCount); err == nil {
		if hourlyCount >= s.config.RateLimit.HourlyLimit {
			return fmt.Errorf("每小时最多发送 %d 条短信", s.config.RateLimit.HourlyLimit)
		}
	}

	// 检查每日发送限制
	dailyKey := fmt.Sprintf("sms:daily:%s:%s", phone, now.Format("20060102"))
	var dailyCount int
	if err := s.cache.Get(ctx, dailyKey, &dailyCount); err == nil {
		if dailyCount >= s.config.RateLimit.DailyLimit {
			return fmt.Errorf("每日最多发送 %d 条短信", s.config.RateLimit.DailyLimit)
		}
	}

	return nil
}

// updateSendRecord 更新发送记录
func (s *SMSCodeService) updateSendRecord(ctx context.Context, phone string) {
	now := time.Now()

	// 更新最后发送时间
	lastSentKey := fmt.Sprintf("sms:last_sent:%s", phone)
	s.cache.Set(ctx, lastSentKey, now, s.config.RateLimit.MinInterval)

	// 更新每小时计数
	hourlyKey := fmt.Sprintf("sms:hourly:%s:%s", phone, now.Format("2006010215"))
	var hourlyCount int
	if err := s.cache.Get(ctx, hourlyKey, &hourlyCount); err == nil {
		s.cache.Set(ctx, hourlyKey, hourlyCount+1, time.Hour)
	} else {
		s.cache.Set(ctx, hourlyKey, 1, time.Hour)
	}

	// 更新每日计数
	dailyKey := fmt.Sprintf("sms:daily:%s:%s", phone, now.Format("20060102"))
	var dailyCount int
	if err := s.cache.Get(ctx, dailyKey, &dailyCount); err == nil {
		s.cache.Set(ctx, dailyKey, dailyCount+1, 24*time.Hour)
	} else {
		s.cache.Set(ctx, dailyKey, 1, 24*time.Hour)
	}
}

// CleanExpiredCodes 清理过期验证码
func (s *SMSCodeService) CleanExpiredCodes(ctx context.Context) error {
	return s.repo.CleanupExpired(ctx)
}