The Mini Shell Extension Framework – Part III

//
// (C) Copyright by Victor Derks <vba64@xs4all.nl>
//
// See README.TXT for the details of the software licence.
//
#pragma once


#include "cfhandler.h"
#include "pidl.h"
#include "util.h"


namespace MSF
{

// Note: handler expect that pidls are alive as long as handler is used.

class CCfShellIdListHandler : public CCfHandler
{
public:
	typedef std::vector<CPidl> CPidls;

	CCfShellIdListHandler(const ITEMIDLIST* pidlFolder, CPidls& pidls) :
		CCfHandler(CFSTR_SHELLIDLIST, true, false),
		m_pidlFolder(pidlFolder),
		m_pidls(pidls)
	{
	}


	virtual HRESULT Validate(const FORMATETC& formatetc) const
	{
		if (formatetc.dwAspect != DVASPECT_CONTENT)
			return DV_E_DVASPECT;

		if (!IsBitSet(formatetc.tymed, TYMED_HGLOBAL))
			return DV_E_TYMED;

		if (formatetc.lindex != -1)
			return DV_E_LINDEX;

		return S_OK;
	}


	virtual void GetData(const FORMATETC&, STGMEDIUM& stgmedium) const
	{
		UINT sizeheader = static_cast<UINT>(sizeof(CIDA) + (sizeof(UINT) * m_pidls.size()));

		UINT size = sizeheader + m_pidlFolder.GetSize();

		for (CPidls::const_iterator it = m_pidls.begin(); it != m_pidls.end(); ++it)
		{
			size += it->GetSize();
		}

		CStgMedium medium(GlobalAllocThrow(size));

		CIDA* pcida = static_cast<CIDA*>(medium.GetHGlobal());

		pcida->cidl = static_cast<UINT>(m_pidls.size());

		UINT offset = sizeheader;
		offset += AddPidlToCida(pcida, m_pidlFolder, 0, offset);

		for (UINT i = 0; i < m_pidls.size(); ++i)
		{
			offset += AddPidlToCida(pcida, m_pidls[i], i + 1, offset);
		}

		medium.Detach(stgmedium);
	}

private:

	CCfShellIdListHandler& operator=(const CCfShellIdListHandler&); // not implemented by design.

	unsigned int AddPidlToCida(CIDA* pcida, const CPidl& pidl, UINT index, UINT offset) const throw()
	{
		pcida->aoffset[index] = offset;

		unsigned int size = pidl.GetSize();
		memcpy(reinterpret_cast<BYTE*>(pcida) + offset, pidl.get(), size);
		return size;
	}

	CPidl   m_pidlFolder;
	CPidls& m_pidls;
};

} // end of MSF namespace