namespace VPNAuth.Server.Database;

public static class GarbageCollector
{
    private static void CollectAuthRequests(Database db)
    {
        foreach (var authRequest in db.AuthRequests)
        {
            if ((DateTime.Now - authRequest.InitTime).TotalMinutes >= 5)
                db.AuthRequests.Remove(authRequest);
        }
    }

    private static void CollectTokens(Database db)
    {
        foreach (var accessToken in db.AccessTokens)
        {
            if ((DateTime.Now - accessToken.CreationTime).TotalDays >= 7)
                db.AccessTokens.Remove(accessToken);
        }
    }

    private static void CollectUserInformation(Database db)
    {
        Config config = Config.Read();
        foreach (var dbUser in db.UserInformation)
        {
            if (config.Users!.All(configUser => configUser.Username != dbUser.Sub))
                db.UserInformation.Remove(dbUser);
        }
    }

    public static void StartLoop()
    {
        while (true)
        {
            using (var db = new Database())
            {
                CollectAuthRequests(db);
                CollectTokens(db);
                CollectUserInformation(db);

                db.SaveChanges();
            }

            Task.Delay(60000).Wait(); // Wait 1 minute
        }
    }

    public static void StartLoopAsync()
        => new Task(StartLoop).Start();
}