package service

import (
	"errors"

	"health-ai/internal/model"
	"health-ai/internal/repository/impl"
	"health-ai/pkg/jwt"

	"golang.org/x/crypto/bcrypt"
)

type AuthService struct {
	userRepo *impl.UserRepositoryImpl
}

func NewAuthService() *AuthService {
	return &AuthService{
		userRepo: impl.NewUserRepository(),
	}
}

// RegisterRequest 注册请求
type RegisterRequest struct {
	Phone    string `json:"phone" binding:"required"`
	Password string `json:"password" binding:"required,min=6"`
	Nickname string `json:"nickname"`
}

// LoginRequest 登录请求
type LoginRequest struct {
	Phone    string `json:"phone" binding:"required"`
	Password string `json:"password" binding:"required"`
}

// AuthResponse 认证响应
type AuthResponse struct {
	Token           string `json:"token"`
	UserID          uint   `json:"user_id"`
	Nickname        string `json:"nickname"`
	Avatar          string `json:"avatar"`
	SurveyCompleted bool   `json:"survey_completed"`
}

// UserInfoResponse 用户信息响应
type UserInfoResponse struct {
	UserID          uint   `json:"user_id"`
	Phone           string `json:"phone"`
	Email           string `json:"email"`
	Nickname        string `json:"nickname"`
	Avatar          string `json:"avatar"`
	SurveyCompleted bool   `json:"survey_completed"`
}

// Register 用户注册
func (s *AuthService) Register(req *RegisterRequest) (*AuthResponse, error) {
	// 检查手机号是否已注册
	existing, _ := s.userRepo.GetByPhone(req.Phone)
	if existing.ID > 0 {
		return nil, errors.New("手机号已注册")
	}

	// 加密密码
	hash, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
	if err != nil {
		return nil, errors.New("密码加密失败")
	}

	// 创建用户
	user := &model.User{
		Phone:        req.Phone,
		PasswordHash: string(hash),
		Nickname:     req.Nickname,
	}
	if user.Nickname == "" {
		// 默认昵称：手机号后4位
		user.Nickname = "用户" + req.Phone[len(req.Phone)-4:]
	}

	if err := s.userRepo.Create(user); err != nil {
		return nil, errors.New("创建用户失败")
	}

	// 生成 Token
	token, err := jwt.GenerateToken(user.ID)
	if err != nil {
		return nil, errors.New("生成Token失败")
	}

	return &AuthResponse{
		Token:           token,
		UserID:          user.ID,
		Nickname:        user.Nickname,
		Avatar:          user.Avatar,
		SurveyCompleted: user.SurveyCompleted,
	}, nil
}

// Login 用户登录
func (s *AuthService) Login(req *LoginRequest) (*AuthResponse, error) {
	user, err := s.userRepo.GetByPhone(req.Phone)
	if err != nil {
		return nil, errors.New("用户不存在")
	}

	if err := bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(req.Password)); err != nil {
		return nil, errors.New("密码错误")
	}

	token, err := jwt.GenerateToken(user.ID)
	if err != nil {
		return nil, errors.New("生成Token失败")
	}

	return &AuthResponse{
		Token:           token,
		UserID:          user.ID,
		Nickname:        user.Nickname,
		Avatar:          user.Avatar,
		SurveyCompleted: user.SurveyCompleted,
	}, nil
}

// GetUserInfo 获取用户信息
func (s *AuthService) GetUserInfo(userID uint) (*UserInfoResponse, error) {
	user, err := s.userRepo.GetByID(userID)
	if err != nil {
		return nil, errors.New("用户不存在")
	}

	return &UserInfoResponse{
		UserID:          user.ID,
		Phone:           user.Phone,
		Email:           user.Email,
		Nickname:        user.Nickname,
		Avatar:          user.Avatar,
		SurveyCompleted: user.SurveyCompleted,
	}, nil
}

// RefreshToken 刷新Token
func (s *AuthService) RefreshToken(oldToken string) (string, error) {
	return jwt.RefreshToken(oldToken)
}

// UpdateProfile 更新用户资料
func (s *AuthService) UpdateProfile(userID uint, nickname, avatar string) error {
	user, err := s.userRepo.GetByID(userID)
	if err != nil {
		return errors.New("用户不存在")
	}

	if nickname != "" {
		user.Nickname = nickname
	}
	if avatar != "" {
		user.Avatar = avatar
	}

	return s.userRepo.Update(user)
}