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.
//
#include "stdafx.h"
#include "../include/shellfolderimpl.h"
#include "../include/browserframeoptionsimpl.h"
#include "../include/itemnamelimitsimpl.h"
#include "../include/strutil.h"
#include "../include/queryinfo.h"
#include "../include/cfhdrop.h"
#include "../include/menu.h"
#include "shellfolderclsid.h"
#include "shellfolderviewcb.h"
#include "shellfolderdataobject.h"
#include "enumidlist.h"
#include "vvvitem.h"
#include "vvvfile.h"
#include "columns.h"
#include "vvvpropertysheet.h"
#include "resource.h"


// Defines for the item context menu.
const UINT ID_DFM_CMD_OPEN = 0;


class ATL_NO_VTABLE CShellFolder :
	public CComObjectRootEx<CComSingleThreadModel>,
	public CComCoClass<CShellFolder, &__uuidof(CShellFolder)>,
	public IShellFolderImpl<CShellFolder, CVVVItem>,
	public IBrowserFrameOptionsImpl,
	public IItemNameLimitsImpl<CShellFolder, CVVVItem>
{
public:
	static HRESULT WINAPI UpdateRegistry(BOOL bRegister) throw()
	{
		UINT nResId = IsShell5OrHigher() ? IDR_SHELLFOLDER : IDR_SHELLFOLDER_WIN98;
		return IShellFolderImpl<CShellFolder, CVVVItem>::UpdateRegistry(
			nResId, bRegister,
			L"Sample ShellExtension ShellFolder", wszVVVExtension, IDS_SHELLFOLDER_TYPE);
	}


	DECLARE_PROTECT_FINAL_CONSTRUCT()

	BEGIN_COM_MAP(CShellFolder)
		COM_INTERFACE_ENTRY2(IPersist, IPersistFolder2)
		COM_INTERFACE_ENTRY(IPersistFolder)
		COM_INTERFACE_ENTRY(IPersistFolder2)
		COM_INTERFACE_ENTRY(IPersistIDList)
		COM_INTERFACE_ENTRY(IShellFolder)  // included for backwards (win9x) compatiblity.
		COM_INTERFACE_ENTRY(IShellFolder2)
		COM_INTERFACE_ENTRY(IShellDetails) // included for backwards (win9x) compatiblity.
		COM_INTERFACE_ENTRY(IBrowserFrameOptions)
		COM_INTERFACE_ENTRY(IShellIcon)
		COM_INTERFACE_ENTRY(IItemNameLimits)
		COM_INTERFACE_ENTRY(IDropTarget)   // enable drag and drop support.
	END_COM_MAP()


	CShellFolder()
	{
		// Register the columns the folder supports in 'detailed' mode.
		RegisterColumn(IDS_SHELLEXT_NAME, LVCFMT_LEFT);
		RegisterColumn(IDS_SHELLEXT_SIZE, LVCFMT_RIGHT);
	}


	// Purpose: called by MSF when the shellfolder needs to show a subfolder.
	void InitializeSubFolder(const CVVVItems& items)
	{
		m_strSubFolder.Empty();

		for (CVVVItems::const_iterator it = items.begin(); it != items.end(); ++it)
		{
			if (!m_strSubFolder.IsEmpty())
			{
				m_strSubFolder += _T("\\");
			}

			m_strSubFolder += ToString(it->GetID());
		}
	}


	// Purpose: Create the shellfolderviewcb that will be used to catch callback events
	//          generated by the system folder view.
	CComPtr<IShellFolderViewCB> CreateShellFolderViewCB()
	{
		return CShellFolderViewCB::CreateInstance(GetRootFolder());
	}


	// Purpose: called by MSF/shell when a number of items are selected and a IDataObject
	//          that contains the items is required.
	CComPtr<IDataObject> CreateDataObject(const ITEMIDLIST* pidlFolder, UINT cidl, const ITEMIDLIST** ppidl)
	{
		return CShellFolderDataObject::CreateInstance(pidlFolder, cidl, ppidl, this);
	}


	// Purpose: called by MSF/shell when it want the current list of 
	//          all items  The shell will walk all IDs and then release the enum.
	CComPtr<IEnumIDList> CreateEnumIDList(HWND /*hwnd*/, DWORD grfFlags)
	{
		auto_ptr<CVVVItems> qitems = CVVVFile(GetPathFolderFile(), m_strSubFolder).GetItems(grfFlags);
		return CEnumIDList::CreateInstance(GetUnknown(), qitems);
	}


	// Purpose: called by MSF when there is no global settings for all items.
	SFGAOF GetAttributeOf(unsigned int cidl, const CVVVItem& item, SFGAOF /*sfgofMask*/) const
	{
		return item.GetAttributeOf(cidl == 1, IsReadOnly(GetPathFolderFile()));
	}


	// Purpose: called by the default context menu. Gives an option to merge
	//          extra commands into the menu.
	HRESULT OnDfmMergeContextMenu(IDataObject* pdataobject, UINT /*uFlags*/, QCMINFO& qcminfo)
	{
		CCfShellIdList cfshellidlist(pdataobject);

		if (cfshellidlist.GetItemCount() == 1)
		{
			// Add 'open' if only 1 item is selected.
			CMenu menu(true);
			menu.AddDefaultItem(ID_DFM_CMD_OPEN, _T("&Open"));
			MergeMenus(qcminfo, menu);

			// Note: XP will automatic make first menu item the default.
			//       Win98, ME and 2k don't do this, so must add as default item.
		}

		return S_OK;
	}


	// Purpose: Called to get the help string for added menu items.
	CString OnDfmGetHelpText(unsigned short nCmdId)
	{
		return LoadString(IDS_SHELLFOLDER_DFM_HELP_BASE + nCmdId);
	}


	HRESULT OnDfmInvokeAddedCommand(HWND hwnd, IDataObject* pdataobject, int nId)
	{
		switch (nId)
		{
			case ID_DFM_CMD_OPEN:
				OnOpen(hwnd, pdataobject);
				break;

			default:
				ATLASSERT(false); // unknown command id detected.
				break;
		}

		return S_OK;
	}


	// Purpose: handle 'open' by showing the name of the selected item.
	void OnOpen(HWND hwnd, IDataObject* pdataobject)
	{
		CVVVItems items;

		RetrieveItems(pdataobject, items);
		ATLASSERT(items.size() == 1);

		if (items[0].IsFolder())
		{
			CPidl pidlFolder(items[0].CreateShellItemIdList());

			GetShellBrowser().BrowseObject(pidlFolder, SBSP_DEFBROWSER | SBSP_RELATIVE);
		}
		else
		{
			CString strMessage = _T("Open on: ") + items[0].GetName();
			IsolationAwareMessageBox(hwnd, strMessage, _T("Open"), MB_OK | MB_ICONQUESTION);
		}
	}


	// Purpose: Called by the shell/MSF when an item must be renamed.
	void OnSetNameOf(HWND /*hwnd*/, CVVVItem& item, const TCHAR* szNewName, SHGDNF shgndf)
	{
		RaiseExceptionIf(shgndf != SHGDN_NORMAL && shgndf != SHGDN_INFOLDER); // not supported 'name'.

		item.SetDisplayName(szNewName, shgndf);

		CVVVFile(GetPathFolderFile(), m_strSubFolder).SetItem(item);
	}


	// Purpose: handles the 'properties request.
	//          The property sheet/page allows the user to change 
	//          the name and size of an item.
	long OnProperties(HWND hwnd, CVVVItems& items)
	{
		ATLASSERT(items.size() == 1);
		CVVVItem& item = items[0];

		long wEventId;
		if (CVVVPropertySheet(item, this).DoModal(hwnd, wEventId) > 0 && wEventId != 0)
		{
			CVVVFile vvvfile(GetPathFolderFile(), m_strSubFolder);
			vvvfile.SetItem(item);
		}

		return wEventId;
	}


	// Purpose: Called by MSF/shell when items must be deleted.
	long OnDelete(HWND hwnd, CVVVItems& items)
	{
		if (hwnd != NULL && !UserConfirmsFileDelete(hwnd, items))
			return 0; // user wants to abort the file deletion process.

		CVVVFile(GetPathFolderFile(), m_strSubFolder).DeleteItems(items);

		return SHCNE_DELETE;
	}


	// Purpose: called by the standard MSF drag handler during drag operations.
	bool IsSupportedClipboardFormat(IDataObject* pdataobject)
	{
		return CCfHDrop::IsFormat(pdataobject);
	}


	// Purpose: called when items are pasted or droped on the shellfolder.
	DWORD AddItemsFromDataObject(DWORD dwEffect, IDataObject* pdataobject)
	{
		CCfHDrop cfhdrop(pdataobject);

		unsigned int nFiles = cfhdrop.GetFileCount();
		for (unsigned int i = 0; i < nFiles; ++i)
		{
			AddItem(cfhdrop.GetFile(i));
		}

		// The VVV sample cannot use optimized move. Just return dwEffect as passed.
		return dwEffect;
	}


	void OnError(HRESULT hr, HWND hwnd, EErrorContext /*errorcontext*/)
	{
		CString strMsg = LoadString(IDS_SHELLFOLDER_CANNOT_PERFORM) + FormatLastError(static_cast<DWORD>(hr));

		IsolationAwareMessageBox(hwnd, strMsg,
			LoadString(IDS_SHELLEXT_ERROR_CAPTION), MB_OK | MB_ICONERROR);
	}

private:

	// Purpose: Ask the user if he is really sure about the file delete action.
	//          Deleted files cannot be restored from the recycle bin.
	bool UserConfirmsFileDelete(HWND hwnd, const CVVVItems& items)
	{
		CString strMessage;
		UINT    nCaptionResId;

		if (items.size() == 1)
		{
			strMessage.FormatMessage(IDS_SHELLFOLDER_DELETE, items[0].GetDisplayName().GetString());
			nCaptionResId = IDS_SHELLFOLDER_FILE_DELETE_CAPTION;
		}
		else
		{
			strMessage.FormatMessage(IDS_SHELLFOLDER_MULTIPLE_DELETE,
				ToString(static_cast<unsigned int>(items.size())).GetString());
			nCaptionResId = IDS_SHELLFOLDER_FILES_DELETE_CAPTION;
		}

		return IsolationAwareMessageBox(hwnd, strMessage,
			LoadString(nCaptionResId), MB_YESNO | MB_ICONQUESTION) == IDYES;
	}


	void AddItem(const CString& strFile)
	{
		const auto_ptr<CVVVItem> qitem(CVVVFile(GetPathFolderFile(), m_strSubFolder).AddItem(strFile));

		ReportAddItem(*qitem);
	}


	bool IsReadOnly(const CString& strFileName) const
	{
		DWORD dwAttributes = GetFileAttributes(strFileName);
		return (dwAttributes & FILE_ATTRIBUTE_READONLY) != 0;
	}


	// Member variables
	CString m_strSubFolder;
};


OBJECT_ENTRY_AUTO(__uuidof(CShellFolder), CShellFolder)