// XBrowseForFolder.h  Version 1.0
//
// Author:  Hans Dietrich
//          hdietrich2@hotmail.com
//
// Description:
//     XBrowseForFolder.cpp implements XBrowseForFolder(), a function that
//     wraps SHBrowseForFolder().
//
// History
//     Version 1.0 - 2003 September 25
//     - Initial public release
//
// This software is released into the public domain.  You are free to use it 
// in any way you like.
//
// This software is provided "as is" with no expressed or implied warranty.  
// I accept no liability for any damage or loss of business that this software 
// may cause.
//
///////////////////////////////////////////////////////////////////////////////

#include <assert.h>
#include <io.h>
#include <shlobj.h>
#include <shellapi.h>

///////////////////////////////////////////////////////////////////////////////
// ScreenToClientX - helper function
static void ScreenToClientX(HWND hWnd, LPRECT lpRect)
{
	assert(::IsWindow(hWnd));
	::ScreenToClient(hWnd, (LPPOINT)lpRect);
	::ScreenToClient(hWnd, ((LPPOINT)lpRect)+1);
}

///////////////////////////////////////////////////////////////////////////////
// MoveWindowX - helper function
static void MoveWindowX(HWND hWnd, RECT& rect, BOOL bRepaint)
{
	assert(::IsWindow(hWnd));
	::MoveWindow(hWnd, rect.left, rect.top,
		rect.right-rect.left, rect.bottom-rect.top, bRepaint);
}

///////////////////////////////////////////////////////////////////////////////
// XBROWSE_FOLDERINFO - structure to pass folder properties to the dialog
struct XBROWSE_FOLDERINFO
{
	LPCSTR lpszInitialFolder;
	LPCSTR lpszCaption;
};

///////////////////////////////////////////////////////////////////////////////
// BrowseCallbackProc - SHBrowseForFolder callback function
static int CALLBACK BrowseCallbackProc(HWND hwnd,		// Window handle to the browse dialog box
									   UINT uMsg,		// Value identifying the event
									   LPARAM lParam,	// Value dependent upon the message 
									   LPARAM lpData)	// Application-defined value that was 
														// specified in the lParam member of the 
														// BROWSEINFO structure
{
	switch (uMsg)
	{
		case BFFM_INITIALIZED:		// sent when the browse dialog box has finished initializing. 
		{
			// remove context help button from dialog caption
			LONG lStyle = ::GetWindowLong(hwnd, GWL_STYLE);
			lStyle &= ~DS_CONTEXTHELP;
			::SetWindowLong(hwnd, GWL_STYLE, lStyle);
			lStyle = ::GetWindowLong(hwnd, GWL_EXSTYLE);
			lStyle &= ~WS_EX_CONTEXTHELP;
			::SetWindowLong(hwnd, GWL_EXSTYLE, lStyle);

			// extract folder properties
			XBROWSE_FOLDERINFO *xinfo = (XBROWSE_FOLDERINFO *)lpData;
			// set caption
			if (xinfo->lpszCaption)
				::SetWindowText(hwnd, xinfo->lpszCaption);
			// set initial directory
			if (xinfo->lpszInitialFolder)
				::SendMessage(hwnd, BFFM_SETSELECTION, TRUE, (LPARAM)xinfo->lpszInitialFolder);

			// find the folder tree and make dialog larger
			HWND hwndTree = FindWindowEx(hwnd, NULL, "SysTreeView32", NULL);
			if (hwndTree)
			{
				// make the dialog larger
				RECT rectDlg;
				::GetWindowRect(hwnd, &rectDlg);
				rectDlg.right += 40;
				rectDlg.bottom += 30;
				MoveWindowX(hwnd, rectDlg, TRUE);
				::GetClientRect(hwnd, &rectDlg);

				// move the Cancel button
				RECT rectCancel = {0};
				HWND hwndCancel = ::GetDlgItem(hwnd, IDCANCEL);
				if (hwndCancel)
					::GetWindowRect(hwndCancel, &rectCancel);
				ScreenToClientX(hwnd, &rectCancel);
				int w = rectCancel.right-rectCancel.left;
				int h = rectCancel.bottom-rectCancel.top;
				rectCancel.bottom = rectDlg.bottom - 5;
				rectCancel.top = rectCancel.bottom - h;
				rectCancel.right = rectDlg.right - 5;
				rectCancel.left = rectCancel.right - w;
				if (hwndCancel)
					MoveWindowX(hwndCancel, rectCancel, FALSE);

				// move the OK button
				RECT rectOK = {0};
				HWND hwndOK = ::GetDlgItem(hwnd, IDOK);
				if (hwndOK)
					::GetWindowRect(hwndOK, &rectOK);
				ScreenToClientX(hwnd, &rectOK);
				rectOK.bottom = rectDlg.bottom - 5;
				rectOK.top = rectOK.bottom - h;
				rectOK.right = rectCancel.left - 10;
				rectOK.left = rectOK.right - w;
				if (hwndOK)
					MoveWindowX(hwndOK, rectOK, FALSE);

				// expand the folder tree to fill the dialog
				RECT rectTree;
				::GetWindowRect(hwndTree, &rectTree);
				ScreenToClientX(hwnd, &rectTree);
				rectTree.top = 5;
				rectTree.left= 5;
				rectTree.bottom = rectOK.top - 5;
				rectTree.right = rectDlg.right - 5;
				MoveWindowX(hwndTree, rectTree, FALSE);
			}
			else
			{
				::OutputDebugString("ERROR - tree control not found.\n");
				assert(hwndTree);
			}
		}
		break;

		case BFFM_SELCHANGED:		// sent when the selection has changed
		{
			char szDir[_MAX_PATH] = { 0 };

			// fail if non-filesystem
			BOOL bRet = SHGetPathFromIDList((LPITEMIDLIST) lParam, szDir);
			if (bRet)
			{
				// fail if folder not accessible
				if (_access(szDir, 00) != 0)
				{
					bRet = FALSE;
				}
				else
				{
					SHFILEINFO sfi;
					::SHGetFileInfo((LPCTSTR)lParam, 0, &sfi, sizeof(sfi), 
							SHGFI_PIDL | SHGFI_ATTRIBUTES);
					//::OutputDebugString("dwAttributes=0x%08X\n", sfi.dwAttributes);

					// fail if pidl is a link
					if (sfi.dwAttributes & SFGAO_LINK)
					{
						//::OutputDebugString("SFGAO_LINK\n");
						bRet = FALSE;
					}
				}
			}

			// if invalid selection, disable the OK button
			if (!bRet)
			{
				::EnableWindow(GetDlgItem(hwnd, IDOK), FALSE);
			}

			//::OutputDebugString("szDir=%s\n", szDir);
		}
		break;
	}
         
	return 0;
}

///////////////////////////////////////////////////////////////////////////////
//
// XBrowseForFolder()
//
// Purpose:     Invoke the SHBrowseForFolder API.  If lpszInitialFolder is
//              supplied, it will be the folder initially selected in the tree 
//              folder list.  Otherwise, the initial folder will be set to the 
//              current directory.  The selected folder will be returned in 
//              lpszBuf.
//
// Parameters:  hWnd              - handle to the owner window for the dialog
//              lpszCaption       - text in title bar
//              lpszInitialFolder - initial folder in tree;  if NULL, the initial
//                                  folder will be the current directory.
//              lpszBuf           - buffer for the returned folder path
//              dwBufSize         - size of lpszBuf in chars
//
// Returns:     BOOL - TRUE = success;  FALSE = user hit Cancel
//
BOOL XBrowseForFolder(HWND hWnd,
					  LPCSTR lpszCaption,
					  LPCSTR lpszInitialFolder,
					  LPSTR lpszBuf,
					  DWORD dwBufSize)
{
	assert(lpszBuf);
	assert(dwBufSize >= MAX_PATH);

	if (lpszBuf == NULL || dwBufSize < MAX_PATH)
		return FALSE;

	lpszBuf[0] = '\0';

	char szInitialPath[_MAX_PATH];
	ZeroMemory(szInitialPath, sizeof(szInitialPath));

	if (lpszInitialFolder && lpszInitialFolder[0] != '\0')
		strncpy(szInitialPath, lpszInitialFolder, sizeof(szInitialPath) - 1);
	else
	{
		// no initial folder, set to current directory
		::GetCurrentDirectory(sizeof(szInitialPath) - 1, szInitialPath);
	}

	// set folder properties
	XBROWSE_FOLDERINFO xinfo;
	xinfo.lpszInitialFolder = szInitialPath;
	xinfo.lpszCaption = lpszCaption;

	BROWSEINFO bi;
	ZeroMemory(&bi, sizeof(BROWSEINFO));

	bi.hwndOwner = hWnd;
	bi.ulFlags   = BIF_RETURNONLYFSDIRS;	// do NOT use BIF_NEWDIALOGSTYLE, 
											// BIF_EDITBOX, or BIF_STATUSTEXT
	bi.lpfn      = BrowseCallbackProc;
	bi.lParam    = (LPARAM) &xinfo;

	LPITEMIDLIST pidl = SHBrowseForFolder(&bi);

	BOOL bRet = FALSE;

	if (pidl)
	{
		char szBuffer[_MAX_PATH];
		szBuffer[0] = '\0';

		if (SHGetPathFromIDList(pidl, szBuffer))
		{
			ZeroMemory(lpszBuf, dwBufSize);
			strncpy(lpszBuf, szBuffer, dwBufSize-1);
			bRet = TRUE;
		}
		else
		{
			::OutputDebugString("SHGetPathFromIDList failed\n");
		}

		IMalloc *pMalloc = NULL; 
		if (SUCCEEDED(SHGetMalloc(&pMalloc)) && pMalloc) 
		{  
			pMalloc->Free(pidl);  
			pMalloc->Release(); 
		}
	}

	return bRet;
}