//
//    Copyright (C) Microsoft.  All rights reserved.
//
#pragma warning disable 1634, 1691

namespace Microsoft.PowerShell.Commands.Internal
{
    using System;
    using System.Runtime.InteropServices;
    using System.Transactions;
    using Microsoft.Win32.SafeHandles;
    using System.Management.Automation;


    [Guid("79427A2B-F895-40e0-BE79-B57DC82ED231"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    internal interface IKernelTransaction
    {
        int GetHandle(out IntPtr pHandle);
    }

    [System.Security.SuppressUnmanagedCodeSecurity]
    internal sealed class SafeTransactionHandle : SafeHandleZeroOrMinusOneIsInvalid
    {
        private const string resBaseName = "RegistryProviderStrings";

        private SafeTransactionHandle(IntPtr handle)
            : base(true)
        {
            this.handle = handle;
        }

        internal static SafeTransactionHandle Create()
        {
            return SafeTransactionHandle.Create(Transaction.Current);
        }

        internal static SafeTransactionHandle Create(Transaction managedTransaction)
        {
            if (managedTransaction == null)
            {
                throw new InvalidOperationException(RegistryProviderStrings.InvalidOperation_NeedTransaction);
            }

            // MSDTC is not available on WinPE machine.
            // CommitableTransaction will use DTC APIs under the covers to get KTM transaction manager interface. 
            // KTM is kernel Transaction Manager to handle file, registry etc and MSDTC provides an integration support 
            // with KTM to handle transaction across kernel resources and MSDTC resources like SQL, MSMQ etc. 
            // We need KTMRM service as well. WinPE doesn’t have these services installed 
            if (Utils.IsWinPEHost() || PsUtils.IsRunningOnProcessorArchitectureARM())
            {
                throw new NotSupportedException(RegistryProviderStrings.NotSupported_KernelTransactions);
            }

            IDtcTransaction dtcTransaction = TransactionInterop.GetDtcTransaction(managedTransaction);
            IKernelTransaction ktmInterface = dtcTransaction as IKernelTransaction;
            if (null == ktmInterface)
            {
                throw new NotSupportedException(RegistryProviderStrings.NotSupported_KernelTransactions);
            }

            IntPtr ktmTxHandle;
            int hr = ktmInterface.GetHandle(out ktmTxHandle);
            HandleError(hr);

            return new SafeTransactionHandle(ktmTxHandle);
        }

        protected override bool ReleaseHandle()
        {
            // We don't care about the value of GetLastError.
#pragma warning suppress 56523
            return Win32Native.CloseHandle(this.handle);
        }

        private static void HandleError(int error)
        {
            if (error != Win32Native.ERROR_SUCCESS)
            {
                throw new System.ComponentModel.Win32Exception(error);
            }
        }
    }
}
