using System;

using Nequeo.Cryptography.Key.Asn1.X509;
using Nequeo.Cryptography.Key.Math;

namespace Nequeo.Cryptography.Key.Asn1.Pkcs
{
    public class IssuerAndSerialNumber
        : Asn1Encodable
    {
        private readonly X509Name name;
        private readonly DerInteger certSerialNumber;

		public static IssuerAndSerialNumber GetInstance(
            object obj)
        {
            if (obj is IssuerAndSerialNumber)
            {
                return (IssuerAndSerialNumber) obj;
            }

			if (obj is Asn1Sequence)
            {
                return new IssuerAndSerialNumber((Asn1Sequence) obj);
            }

			throw new ArgumentException("Unknown object in factory: " + obj.GetType().FullName, "obj");
		}

		private IssuerAndSerialNumber(
            Asn1Sequence seq)
        {
			if (seq.Count != 2)
				throw new ArgumentException("Wrong number of elements in sequence", "seq");

			this.name = X509Name.GetInstance(seq[0]);
            this.certSerialNumber = DerInteger.GetInstance(seq[1]);
        }

		public IssuerAndSerialNumber(
            X509Name	name,
            BigInteger	certSerialNumber)
        {
            this.name = name;
            this.certSerialNumber = new DerInteger(certSerialNumber);
        }

		public IssuerAndSerialNumber(
            X509Name	name,
            DerInteger	certSerialNumber)
        {
            this.name = name;
            this.certSerialNumber = certSerialNumber;
        }

		public X509Name Name
		{
			get { return name; }
		}

		public DerInteger CertificateSerialNumber
		{
			get { return certSerialNumber; }
		}

		public override Asn1Object ToAsn1Object()
        {
			return new DerSequence(name, certSerialNumber);
        }
    }
}
