package service

import (
	"context"
	"errors"
	"tailly_back_v2/internal/domain"
	"tailly_back_v2/internal/repository"
	"tailly_back_v2/pkg/auth"
	"time"
)

type UserService interface {
	GetByID(ctx context.Context, id int) (*domain.User, error)
	GetAll(ctx context.Context, id int) ([]*domain.User, error)
	GetByEmail(ctx context.Context, email string) (*domain.User, error)
	UpdateProfile(ctx context.Context, id int, username, email, avatar string) (*domain.User, error)
	ChangePassword(ctx context.Context, id int, oldPassword, newPassword string) error
}

type userService struct {
	userRepo  repository.UserRepository
	tokenAuth *auth.TokenAuth
}

func (s *userService) GetByEmail(ctx context.Context, email string) (*domain.User, error) {
	user, err := s.userRepo.GetByEmail(ctx, email)
	if err != nil {
		if errors.Is(err, repository.ErrUserNotFound) {
			return nil, errors.New("user not found")
		}
		return nil, err
	}
	return user, nil
}

func NewUserService(userRepo repository.UserRepository) *userService {
	return &userService{
		userRepo: userRepo,
	}
}

func (s *userService) GetByID(ctx context.Context, id int) (*domain.User, error) {
	user, err := s.userRepo.GetByID(ctx, id)
	if err != nil {
		if errors.Is(err, repository.ErrUserNotFound) {
			return nil, errors.New("user not found")
		}
		return nil, err
	}

	// Очищаем пароль перед возвратом
	user.Password = ""
	return user, nil
}

func (s *userService) UpdateProfile(ctx context.Context, id int, username, email, avatar string) (*domain.User, error) {
	user, err := s.userRepo.GetByID(ctx, id)
	if err != nil {
		return nil, err
	}

	// Проверяем email на уникальность
	if email != user.Email {
		if _, err := s.userRepo.GetByEmail(ctx, email); err == nil {
			return nil, errors.New("email already in use")
		}
	}

	user.Username = username
	user.Email = email
	user.Avatar = avatar
	user.UpdatedAt = time.Now()

	if err := s.userRepo.Update(ctx, user); err != nil {
		return nil, err
	}

	// Очищаем пароль перед возвратом
	user.Password = ""
	return user, nil
}

func (s *userService) ChangePassword(ctx context.Context, id int, oldPassword, newPassword string) error {
	user, err := s.userRepo.GetByID(ctx, id)
	if err != nil {
		return err
	}

	if !auth.CheckPasswordHash(oldPassword, user.Password) {
		return errors.New("invalid current password")
	}

	hashedPassword, err := auth.HashPassword(newPassword)
	if err != nil {
		return err
	}

	user.Password = hashedPassword
	return s.userRepo.Update(ctx, user)
}

func (s *userService) GetAll(ctx context.Context, id int) ([]*domain.User, error) {
	users, err := s.userRepo.GetAll(ctx, id)
	if err != nil {
		return nil, err
	}

	// Возвращаем пустой слайс вместо nil
	if users == nil {
		return []*domain.User{}, nil
	}

	return users, nil
}