using SQLite;

namespace Backend.Model.Relations;

public class Session : Relation<String, Int64>
{
    [Indexed] public String   Token     { get => Left ; set => Left  = value;}
    [Indexed] public Int64    UserId    { get => Right; set => Right = value;}
    [Indexed] public DateTime ExpiresAt { get; set; }

    [Ignore] public Boolean Valid   => ExpiresAt > DateTime.Now;
    [Ignore] public Boolean Expired => !Valid;
    
    [Obsolete("To be used only by serializer")]
    public Session()
    {}

    public Session(User user) : this(user, TimeSpan.FromDays(7))
    {
    }

    public Session(User user, TimeSpan validFor)
    {
        Token = CreateToken();
        UserId = user.Id;
        ExpiresAt = DateTime.Now + validFor;
    }
    
    private static String CreateToken()
    {
        var token = new Byte[16]; // 128 bit
        Random.Shared.NextBytes(token);
        return Convert.ToBase64String(token);
    }
}