using System;
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.CryptoPro;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities;

namespace Org.BouncyCastle.Crypto.Parameters;

public abstract class ECKeyParameters : AsymmetricKeyParameter
{
	private static readonly string[] algorithms = new string[6] { "EC", "ECDSA", "ECDH", "ECDHC", "ECGOST3410", "ECMQV" };

	private readonly string algorithm;

	private readonly ECDomainParameters parameters;

	private readonly DerObjectIdentifier publicKeyParamSet;

	public string AlgorithmName => algorithm;

	public ECDomainParameters Parameters => parameters;

	public DerObjectIdentifier PublicKeyParamSet => publicKeyParamSet;

	protected ECKeyParameters(string algorithm, bool isPrivate, ECDomainParameters parameters)
		: base(isPrivate)
	{
		if (algorithm == null)
		{
			throw new ArgumentNullException("algorithm");
		}
		if (parameters == null)
		{
			throw new ArgumentNullException("parameters");
		}
		this.algorithm = VerifyAlgorithmName(algorithm);
		this.parameters = parameters;
	}

	protected ECKeyParameters(string algorithm, bool isPrivate, DerObjectIdentifier publicKeyParamSet)
		: base(isPrivate)
	{
		if (algorithm == null)
		{
			throw new ArgumentNullException("algorithm");
		}
		if (publicKeyParamSet == null)
		{
			throw new ArgumentNullException("publicKeyParamSet");
		}
		this.algorithm = VerifyAlgorithmName(algorithm);
		parameters = LookupParameters(publicKeyParamSet);
		this.publicKeyParamSet = publicKeyParamSet;
	}

	public override bool Equals(object obj)
	{
		if (obj == this)
		{
			return true;
		}
		if (!(obj is ECDomainParameters obj2))
		{
			return false;
		}
		return Equals(obj2);
	}

	protected bool Equals(ECKeyParameters other)
	{
		if (parameters.Equals(other.parameters))
		{
			return Equals((AsymmetricKeyParameter)other);
		}
		return false;
	}

	public override int GetHashCode()
	{
		return parameters.GetHashCode() ^ base.GetHashCode();
	}

	internal ECKeyGenerationParameters CreateKeyGenerationParameters(SecureRandom random)
	{
		if (publicKeyParamSet != null)
		{
			return new ECKeyGenerationParameters(publicKeyParamSet, random);
		}
		return new ECKeyGenerationParameters(parameters, random);
	}

	internal static string VerifyAlgorithmName(string algorithm)
	{
		string result = Platform.ToUpperInvariant(algorithm);
		if (Array.IndexOf((Array)algorithms, (object?)algorithm, 0, algorithms.Length) < 0)
		{
			throw new ArgumentException("unrecognised algorithm: " + algorithm, "algorithm");
		}
		return result;
	}

	internal static ECDomainParameters LookupParameters(DerObjectIdentifier publicKeyParamSet)
	{
		if (publicKeyParamSet == null)
		{
			throw new ArgumentNullException("publicKeyParamSet");
		}
		ECDomainParameters eCDomainParameters = ECGost3410NamedCurves.GetByOid(publicKeyParamSet);
		if (eCDomainParameters == null)
		{
			X9ECParameters x9ECParameters = ECKeyPairGenerator.FindECCurveByOid(publicKeyParamSet);
			if (x9ECParameters == null)
			{
				throw new ArgumentException("OID is not a valid public key parameter set", "publicKeyParamSet");
			}
			eCDomainParameters = new ECDomainParameters(x9ECParameters.Curve, x9ECParameters.G, x9ECParameters.N, x9ECParameters.H, x9ECParameters.GetSeed());
		}
		return eCDomainParameters;
	}
}