package services

import (
	"database/sql"
	"go-weather/models"
	"time"

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

type UserService struct {
	db *sql.DB
}

func NewUserService(db *sql.DB) *UserService {
	return &UserService{db: db}
}

func (s *UserService) CreateUser(email string, password string) (*models.User, error) {
	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)

	if err != nil {
		return nil, err
	}

	var user models.User
	err = s.db.QueryRow(
		`INSERT INTO users (email, password_hash, created_at)
		 VALUES ($1, $2, $3)
		 RETURNING id, email, created_at`,
		email, string(hashedPassword), time.Now(),
	).Scan(&user.ID, &user.Email, &user.CreatedAt)

	if err != nil {
		return nil, err
	}

	return &user, nil

}

func (s *UserService) GetUserByEmail(email string) (*models.User, error) {

	var user models.User
	err := s.db.QueryRow(
		`SELECT id, email, password_hash, created_at
		 FROM users
		 WHERE email = $1`, email,
	).Scan(&user.ID, &user.Email, &user.PasswordHash, &user.CreatedAt)

	if err != nil {
		return nil, nil
	}

	return &user, nil
}

func (s *UserService) EmailExists(email string) (bool, error) {
	var exists bool
	err := s.db.QueryRow(`SELECT EXISTS(SELECT 1 FROM users WHERE email = $1)`, email).Scan(&exists)
	return exists, err
}
func (s *UserService) ValidatePassword(user *models.User, password string) bool {
	err := bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(password))
	return err == nil
}