package auth

import (
	"database/sql"
	"github.com/google/uuid"
	"log"
	db "photodisk/internal/db/sqlite"
	"time"
)

var (
	ErrUserNotFound    = Error{"user not found"}
	ErrSessionNotFound = Error{"session not found"}
)

type User struct {
	Id       int    `db:"id"`
	Username string `db:"username"`
	Password string `db:"password"`
}

type Session struct {
	Id        string `db:"id"`
	UserId    int    `db:"user_id"`
	ExpiresAt string `db:"expires_at"`
}

func GenerateToken() string {
	// generate token using uuid
	return uuid.New().String()
}

func CreateSession(userId int, expireAt time.Time) (string, error) {
	token := GenerateToken()
	_, err := db.GetDb().Exec("INSERT INTO sessions (id, user_id, expires_at) VALUES (?, ?, ?)", token, userId, expireAt)
	if err != nil {
		log.Println(err)
		return "", err
	}

	return token, nil
}

func CheckSession(sessionId string) (User, error) {
	user := User{}
	q := `SELECT users.id, users.username 
		FROM users 
		JOIN sessions ON users.id = sessions.user_id 
		WHERE sessions.id = ? AND sessions.expires_at > datetime('now')`

	err := db.GetDb().Get(&user, q, sessionId)
	if err != nil {
		if err != sql.ErrNoRows {
			log.Println(err)
		}

		return User{}, ErrSessionNotFound
	}

	return user, nil
}

func Login(username, password string) (User, error) {
	user := User{}
	err := db.GetDb().Get(&user, "SELECT * FROM users WHERE username = ?", username)
	if err != nil {
		log.Println(err)
		if err != sql.ErrNoRows {
		}

		return User{}, ErrUserNotFound
	}

	err = CheckPasswordHash(password, user.Password)
	if err != nil {
		log.Println(err)
		return User{}, err
	}

	return user, nil
}