namespace Prac7Meow
{
    internal class Letter
    {
        public int Number { get; }
        public string Sender { get; }
        public string Recipient { get; }
        public double Weight { get; }
        public int TermDays { get; }

        public Letter(int number, string sender, string recipient, double weight, int termDays)
        {
            if (number <= 0)                          throw new ArgumentOutOfRangeException( nameof(number),             "Number must be > 0"   );
            if (string.IsNullOrWhiteSpace(sender))    throw new ArgumentException(           "Sender can't be empty",    nameof(sender)         );
            if (string.IsNullOrWhiteSpace(recipient)) throw new ArgumentException(           "Recipient can't be empty", nameof(recipient)      );
            if (weight <= 0)                          throw new ArgumentOutOfRangeException( nameof(weight),             "Weight must be > 0"   );
            if (termDays <= 0)                        throw new ArgumentOutOfRangeException( nameof(termDays),           "TermDays must be > 0" );

            Number    = number;
            Sender    = sender;
            Recipient = recipient;
            Weight    = weight;
            TermDays  = termDays;
        }

        public override string ToString() => $"Письмо #{Number}: {Sender} -> {Recipient}, {Weight:F1} г, срок {TermDays} дн.";
    }
}