/****************************** Module Header ******************************\
Module Name:  ClassFactory.cpp
Copyright (c) Microsoft Corporation.

The file implements the class factory for the Handler COM class. 

This source is subject to the Microsoft Public License.
See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
All other rights reserved.

THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, 
EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED 
WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
\***************************************************************************/

#include "ClassFactory.h"

#include "PreviewHandler.h"
#include "ThumbnailProvider.h"

#include <new>
#include <Shlwapi.h>

#include "Config.h"


extern long g_cRefDll;


ClassFactory::ClassFactory() : m_cRef(1)
{
  InterlockedIncrement(&g_cRefDll);
}

ClassFactory::~ClassFactory()
{
  InterlockedDecrement(&g_cRefDll);
}


//
// IUnknown
//

IFACEMETHODIMP ClassFactory::QueryInterface(REFIID riid, void **ppv)
{
  static const QITAB qit[] =
  {
    QITABENT(ClassFactory, IClassFactory),
    { 0 },
  };
  return QISearch(this, qit, riid, ppv);
}

IFACEMETHODIMP_(ULONG) ClassFactory::AddRef()
{
  return InterlockedIncrement(&m_cRef);
}

IFACEMETHODIMP_(ULONG) ClassFactory::Release()
{
  ULONG cRef = InterlockedDecrement(&m_cRef);
  if (0 == cRef)
  {
    delete this;
  }
  return cRef;
}


// 
// IClassFactory
//

IFACEMETHODIMP ClassFactory::CreateInstance(IUnknown *pUnkOuter, REFIID riid, void **ppv)
{
  HRESULT hr = CLASS_E_NOAGGREGATION;

  // pUnkOuter is used for aggregation. We do not support it in the sample.
  if (pUnkOuter == NULL)
  {
    hr = E_OUTOFMEMORY;

    // Create the COM component.
#if defined(DEFINE_PREVIEWHANDLER)
    PreviewHandler *pExt = new (std::nothrow) PreviewHandler();
#elif defined( DEFINE_THUMBNAILHANDLER)
    ThumbnailProvider *pExt = new (std::nothrow) ThumbnailProvider();
#endif
    if (pExt)
    {
      // Query the specified interface.
      hr = pExt->QueryInterface(riid, ppv);
      pExt->Release();
    }
  }

  return hr;
}

IFACEMETHODIMP ClassFactory::LockServer(BOOL fLock)
{
  if (fLock)
  {
    InterlockedIncrement(&g_cRefDll);
  }
  else
  {
    InterlockedDecrement(&g_cRefDll);
  }
  return S_OK;
}