using System;
using System.Numerics;
using System.Text;

namespace ArchestrAServices.Contract;

public class EncryptionBase
{
	protected BigInteger DH_p = BigInteger.Zero;

	protected BigInteger DH_g = BigInteger.Zero;

	public string DH_passphrase { get; set; }

	public string hashAlgorithm { get; set; }

	public byte[] NegotiatedKey { get; protected set; }

	public byte[] Encrypt(byte[] PlainPayload, byte[] EncryptionKey)
	{
		if (PlainPayload == null)
		{
			throw new ArgumentNullException("PlainPayload");
		}
		if (EncryptionKey == null)
		{
			throw new ArgumentNullException("EncryptionKey");
		}
		byte[] bytes = Encoding.UTF8.GetBytes(Constants.SaltValue);
		byte[] bytes2 = Encoding.UTF8.GetBytes(Constants.InitialVector);
		return AuthenticationCryptography.Encrypt(PlainPayload, EncryptionKey, bytes, Constants.hashAlgorithm, Constants.PasswordIterations, bytes2, Constants.KeySize);
	}

	public byte[] Decrypt(byte[] EncryptedPayload, byte[] EncryptionKey)
	{
		if (EncryptedPayload == null)
		{
			throw new ArgumentNullException("EncryptedPayload");
		}
		if (EncryptionKey == null)
		{
			throw new ArgumentNullException("EncryptionKey");
		}
		byte[] bytes = Encoding.UTF8.GetBytes(Constants.SaltValue);
		byte[] bytes2 = Encoding.UTF8.GetBytes(Constants.InitialVector);
		byte[] array = AuthenticationCryptography.Decrypt(EncryptedPayload, EncryptionKey, bytes, Constants.hashAlgorithm, Constants.PasswordIterations, bytes2, Constants.KeySize);
		int num = array.Length;
		int num2 = array.Length - 1;
		while (num2 > 1 && array[num2] == 0)
		{
			num--;
			num2--;
		}
		byte[] array2 = new byte[num];
		Array.Copy(array, array2, num);
		return array2;
	}

	public byte[] Encrypt(string PlainPayloadString, string EncryptionPassphrase)
	{
		if (string.IsNullOrEmpty(PlainPayloadString))
		{
			throw new ArgumentException("PlainPayloadString");
		}
		if (string.IsNullOrEmpty(EncryptionPassphrase))
		{
			throw new ArgumentException("EncryptionPassphrase");
		}
		byte[] bytes = Encoding.UTF8.GetBytes(Constants.SaltValue);
		byte[] bytes2 = Encoding.UTF8.GetBytes(Constants.InitialVector);
		byte[] bytes3 = Encoding.UTF8.GetBytes(EncryptionPassphrase);
		return AuthenticationCryptography.Encrypt(Encoding.UTF8.GetBytes(PlainPayloadString), bytes3, bytes, Constants.hashAlgorithm, Constants.PasswordIterations, bytes2, Constants.KeySize);
	}

	public string Decrypt(byte[] EncryptedPayload, string EncryptionPassphrase)
	{
		if (EncryptedPayload == null)
		{
			throw new ArgumentNullException("EncryptedPayload");
		}
		if (string.IsNullOrEmpty(EncryptionPassphrase))
		{
			throw new ArgumentException("EncryptionPassphrase");
		}
		byte[] bytes = Encoding.UTF8.GetBytes(Constants.SaltValue);
		byte[] bytes2 = Encoding.UTF8.GetBytes(Constants.InitialVector);
		byte[] bytes3 = Encoding.UTF8.GetBytes(EncryptionPassphrase);
		byte[] array = AuthenticationCryptography.Decrypt(EncryptedPayload, bytes3, bytes, Constants.hashAlgorithm, Constants.PasswordIterations, bytes2, Constants.KeySize);
		int num = array.Length;
		int num2 = array.Length - 1;
		while (num2 > 1 && array[num2] == 0)
		{
			num--;
			num2--;
		}
		return Encoding.UTF8.GetString(array, 0, num);
	}
}