using System;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Utilities;

namespace Org.BouncyCastle.Asn1.X509;

public class RsaPublicKeyStructure : Asn1Encodable
{
	private BigInteger modulus;

	private BigInteger publicExponent;

	public BigInteger Modulus => modulus;

	public BigInteger PublicExponent => publicExponent;

	public static RsaPublicKeyStructure GetInstance(Asn1TaggedObject obj, bool explicitly)
	{
		return GetInstance(Asn1Sequence.GetInstance(obj, explicitly));
	}

	public static RsaPublicKeyStructure GetInstance(object obj)
	{
		if (obj == null || obj is RsaPublicKeyStructure)
		{
			return (RsaPublicKeyStructure)obj;
		}
		if (obj is Asn1Sequence)
		{
			return new RsaPublicKeyStructure((Asn1Sequence)obj);
		}
		throw new ArgumentException("Invalid RsaPublicKeyStructure: " + Platform.GetTypeName(obj));
	}

	public RsaPublicKeyStructure(BigInteger modulus, BigInteger publicExponent)
	{
		if (modulus == null)
		{
			throw new ArgumentNullException("modulus");
		}
		if (publicExponent == null)
		{
			throw new ArgumentNullException("publicExponent");
		}
		if (modulus.SignValue <= 0)
		{
			throw new ArgumentException("Not a valid RSA modulus", "modulus");
		}
		if (publicExponent.SignValue <= 0)
		{
			throw new ArgumentException("Not a valid RSA public exponent", "publicExponent");
		}
		this.modulus = modulus;
		this.publicExponent = publicExponent;
	}

	private RsaPublicKeyStructure(Asn1Sequence seq)
	{
		if (seq.Count != 2)
		{
			throw new ArgumentException("Bad sequence size: " + seq.Count);
		}
		modulus = DerInteger.GetInstance(seq[0]).PositiveValue;
		publicExponent = DerInteger.GetInstance(seq[1]).PositiveValue;
	}

	public override Asn1Object ToAsn1Object()
	{
		return new DerSequence(new DerInteger(Modulus), new DerInteger(PublicExponent));
	}
}