ExplorerBHO.cpp

// Classic Shell (c) 2009-2017, Ivo Beltchev
// Open-Shell (c) 2017-2018, The Open-Shell Team
// Confidential information of Ivo Beltchev. Not for disclosure or distribution without prior written consent from the author

// ExplorerBHO.cpp : Implementation of CExplorerBHO

#include "stdafx.h"
#include "ExplorerBHO.h"
#include "Settings.h"
#include "ResourceHelper.h"
#include "resource.h"
#include "SettingsUI.h"
#include "Translations.h"
#include "SettingsUIHelper.h"
#include "DownloadHelper.h"
#include "FNVHash.h"
#include "dllmain.h"
#include <uxtheme.h>
#include <dwmapi.h>
#include <Ntquery.h>
#include <algorithm>

// CExplorerBHO - a browser helper object that implements Alt+Enter for the folder tree

const UINT_PTR TIMER_NAVIGATE='CLSH';

int CExplorerBHO::s_AutoNavDelay;

static void GetTreeItemPidl( HTREEITEM hItem, HWND hwndTree, PIDLIST_ABSOLUTE *result )
{
	// find the PIDL of the tree item (combine all child PIDLs from the current item and its parents)
	CAbsolutePidl pidl;
	while (hItem)
	{
		TVITEMEX info={TVIF_PARAM,hItem};
		TreeView_GetItem(hwndTree,&info);
		PIDLIST_RELATIVE **pidl1=(PIDLIST_RELATIVE**)info.lParam;
		if (!pidl1 || !*pidl1 || !**pidl1)
		{
			pidl.Clear();
			break;
		}
		pidl.Attach(pidl?ILCombine((PIDLIST_ABSOLUTE)**pidl1,pidl):(PIDLIST_ABSOLUTE)ILClone(**pidl1));
		hItem=TreeView_GetParent(hwndTree,hItem);
	}
	*result=pidl.Detach();
}

LRESULT CALLBACK CExplorerBHO::SubclassTreeParentProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	// when the tree selection changes start a timer to navigate to the new folder in 100ms
	if (uMsg==WM_NOTIFY && ((NMHDR*)lParam)->code==TVN_SELCHANGED)
	{
		if (GetSettingInt(L"AutoNavigate")==2 || ((NMTREEVIEW*)lParam)->action==TVC_BYKEYBOARD)
			SetTimer(((NMHDR*)lParam)->hwndFrom,TIMER_NAVIGATE,s_AutoNavDelay,NULL);
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

// Subclass the tree control to:
//   - support Alt+Enter
//   - navigate to the new folder when you go up/down with the keyboard
//   - fix the random scrolling of the tree when a folder is expanded
//   - change the tree styles to achieve different looks
LRESULT CALLBACK CExplorerBHO::SubclassTreeProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	if (uMsg==TVM_ENSUREVISIBLE && (dwRefData&1))
	{
		// HACK! there is a bug in Win7 Explorer and when the selected folder is expanded for the first time it sends TVM_ENSUREVISIBLE for
		// the root tree item. This causes the navigation pane to scroll up. To work around the bug we ignore TVM_ENSUREVISIBLE if it tries
		// to show the root item and it is not selected
		HTREEITEM hItem=(HTREEITEM)lParam;
		if (!TreeView_GetParent(hWnd,hItem) && !(TreeView_GetItemState(hWnd,hItem,TVIS_SELECTED)&TVIS_SELECTED))
			return 0;
	}
	if (uMsg==WM_TIMER && wParam==TIMER_NAVIGATE)
	{
		// time to navigate to the selected folder (only if different from the current folder)
		KillTimer(hWnd,TIMER_NAVIGATE);
		if (GetFocus()!=hWnd)
			return 0;
		CAbsolutePidl pidl;
		GetTreeItemPidl(TreeView_GetSelection(hWnd),hWnd,&pidl);
		if (pidl)
		{
			bool bSameFolder=false;
			CExplorerBHO *pThis=GetTlsData()->bho;
			CComPtr<IShellView> pView;
			if (pThis->m_pBrowser && SUCCEEDED(pThis->m_pBrowser->QueryActiveShellView(&pView)))
			{
				CComQIPtr<IFolderView> pView2=pView;

				CComPtr<IPersistFolder2> pFolder;
				CAbsolutePidl pidl2;
				if (pView2 && SUCCEEDED(pView2->GetFolder(IID_IPersistFolder2,(void**)&pFolder)) && SUCCEEDED(pFolder->GetCurFolder(&pidl2)) && pidl2)
				{
					if (ILIsEqual(pidl,pidl2))
						bSameFolder=true;
				}
			}
			if (!bSameFolder)
				SendMessage(hWnd,WM_KEYDOWN,VK_SPACE,0);
		}
		return 0;
	}

	// ignore the Alt+Enter syscharacter (to stop the tree view from beeping)
	if (uMsg==WM_SYSCHAR && wParam==VK_RETURN)
		return 0;

	if (uMsg==WM_SYSKEYDOWN && wParam==VK_RETURN)
	{
		// Alt+Enter is pressed
		// if this message was for the folder tree, show the properties of the selected item
		if (GetSettingBool(L"AltEnter") && ShowTreeProperties(hWnd))
			return 0;
	}

	if ((uMsg==WM_LBUTTONDOWN || uMsg==WM_LBUTTONDBLCLK) && (wParam&MK_CONTROL))
	{
		TVHITTESTINFO test;
		test.pt.x=(short)LOWORD(lParam);
		test.pt.y=(short)HIWORD(lParam);
		HTREEITEM hItem=TreeView_HitTest(hWnd,&test);
		if (test.flags&TVHT_ONITEM)
		{
			CAbsolutePidl pidl;
			GetTreeItemPidl(hItem,hWnd,&pidl);
			if (pidl)
			{
				CExplorerBHO *pThis=GetTlsData()->bho;
				if (pThis->m_pBrowser)
				{
					pThis->m_pBrowser->BrowseObject(pidl,SBSP_NEWBROWSER|SBSP_ABSOLUTE);
				}
			}
		}
		return 0;
	}

	if (uMsg==TVM_SETEXTENDEDSTYLE && wParam==(TVS_EX_FADEINOUTEXPANDOS|TVS_EX_AUTOHSCROLL|0x80000000) && lParam==0)
	{
		wParam&=0x7FFFFFFF;

		if (GetSettingInt(L"AutoNavigate")>0)
			SetWindowSubclass(GetParent(hWnd),SubclassTreeParentProc,'CLSH',0);

		if (!GetSettingBool(L"NoFadeButtons"))
			wParam&=~TVS_EX_FADEINOUTEXPANDOS;

		int indent=-1;
		if (GetSettingBool(L"FullIndent"))
			indent=0;

		int treeStyle=GetSettingInt(L"TreeStyle");
		if (treeStyle==STYLE_CLASSIC && GetWinVersion()>=WIN_VER_WIN10)
			treeStyle=STYLE_VISTA;
		DWORD style=GetWindowLong(hWnd,GWL_STYLE);
		if (treeStyle!=STYLE_VISTA)
		{
			SetWindowTheme(hWnd,NULL,NULL);
			if (treeStyle==STYLE_SIMPLE)
			{
				style|=TVS_SINGLEEXPAND|TVS_TRACKSELECT;
				style&=~TVS_HASLINES;
			}
			else
			{
				style|=TVS_HASLINES;
				style&=~(TVS_SINGLEEXPAND|TVS_TRACKSELECT);
				wParam|=TVS_EX_FADEINOUTEXPANDOS;
				HIMAGELIST images=TreeView_GetImageList(hWnd,TVSIL_NORMAL);
				int cx, cy;
				ImageList_GetIconSize(images,&cx,&cy);
				indent=cx+3;
			}
		}
		int scroll=GetSettingInt(L"HScrollbar");

		if ((scroll==0 && treeStyle==STYLE_VISTA) || scroll==1)
			wParam&=~TVS_EX_AUTOHSCROLL;
		if ((scroll==0 && treeStyle!=STYLE_VISTA) || scroll==2)
			style&=~TVS_NOHSCROLL;

		SetWindowLong(hWnd,GWL_STYLE,style);

		if (indent>=0)
			TreeView_SetIndent(hWnd,indent);

		int d=GetSettingInt(L"TreeItemSpacing");
		if (d)
		{
			CExplorerBHO *pThis=GetTlsData()->bho;
			pThis->m_TreeItemHeight=TreeView_GetItemHeight(hWnd)+d;
			TreeView_SetItemHeight(hWnd,pThis->m_TreeItemHeight);
		}

		if (wParam==0)
			return 0;
	}

	if (uMsg==WM_SETTINGCHANGE)
	{
		LRESULT res=DefSubclassProc(hWnd,uMsg,wParam,lParam);
		int indent=-1;
		if (GetSettingBool(L"FullIndent"))
			indent=0;

		if (GetSettingInt(L"TreeStyle")==STYLE_CLASSIC && GetWinVersion()<WIN_VER_WIN10)
		{
			HIMAGELIST images=TreeView_GetImageList(hWnd,TVSIL_NORMAL);
			int cx, cy;
			ImageList_GetIconSize(images,&cx,&cy);
			indent=cx+3;
		}
		if (indent>=0)
			TreeView_SetIndent(hWnd,indent);
		return res;
	}
	if (uMsg==TVM_SETITEMHEIGHT)
	{
		CExplorerBHO *pThis=GetTlsData()->bho;
		if (pThis->m_TreeItemHeight>0)
			wParam=pThis->m_TreeItemHeight;
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

LRESULT CALLBACK CExplorerBHO::HookExplorer( int nCode, WPARAM wParam, LPARAM lParam )
{
	// wait for the tree control to be created and subclass it
	if (nCode==HCBT_CREATEWND)
	{
		HWND hWnd=(HWND)wParam;
		CBT_CREATEWND *pCreate=(CBT_CREATEWND*)lParam;
		if (pCreate->lpcs->lpszClass>(LPTSTR)0xFFFF && _wcsicmp(pCreate->lpcs->lpszClass,WC_TREEVIEW)==0)
		{
			HWND parent=GetAncestor(pCreate->lpcs->hwndParent,GA_ROOT);
			wchar_t name[256];
			if (GetClassName(parent,name,_countof(name)) && _wcsicmp(name,L"CabinetWClass")==0)
			{
				DWORD_PTR settings=0;
				if (GetWinVersion()==WIN_VER_WIN7 && GetSettingBool(L"FixFolderScroll"))
					settings|=1;
				SetWindowSubclass(hWnd,SubclassTreeProc,'CLSH',settings);
				PostMessage(hWnd,TVM_SETEXTENDEDSTYLE,TVS_EX_FADEINOUTEXPANDOS|TVS_EX_AUTOHSCROLL|0x80000000,0);
			}
		}
		else if (pCreate->lpcs->lpszClass>(LPTSTR)0xFFFF && _wcsicmp(pCreate->lpcs->lpszClass,L"DUIViewWndClassName")==0)
		{
			TlsData *pTlsData=GetTlsData();
			if (!pTlsData->bho->m_DUIView)
			{
				pTlsData->bho->m_DUIView=hWnd;
				SetWindowSubclass(pTlsData->bho->m_DUIView,SubclassDUIViewProc,(UINT_PTR)pTlsData->bho,'CLSH');
			}
		}
	}
	return CallNextHookEx(NULL,nCode,wParam,lParam);
}

LRESULT CALLBACK CExplorerBHO::HookKeyboard( int nCode, WPARAM wParam, LPARAM lParam )
{
	// wait for the tree control to be created and subclass it
	if (nCode==HC_ACTION)
	{
		TlsData *pTlsData=GetTlsData();
		if (wParam==pTlsData->bho->m_AltD && (lParam&0x20000000))
		{
			if (lParam&0x80000000)
			{
				return 0;
			}
			else
			{
				if (IsWindow(pTlsData->bho->m_Breadcrumbs) && IsWindowVisible(pTlsData->bho->m_Breadcrumbs))
				{
					SetFocus(pTlsData->bho->m_Breadcrumbs);
					SendMessage(pTlsData->bho->m_Breadcrumbs,WM_KEYDOWN,VK_SPACE,0);
					SendMessage(pTlsData->bho->m_Breadcrumbs,WM_KEYUP,VK_SPACE,0);
					return 0;
				}
			}
		}
		if (wParam==(pTlsData->bho->m_UpHotkey&255) && !(lParam&0x80000000))
		{
			// Backspace goes to the parent folder, but only if no window has the caret
			GUITHREADINFO info={sizeof(info)};
			if (GetGUIThreadInfo(GetCurrentThreadId(),&info) && !info.hwndCaret)
			{
				bool bShift1=(pTlsData->bho->m_UpHotkey&(HOTKEYF_SHIFT<<8))!=0;
				bool bCtrl1=(pTlsData->bho->m_UpHotkey&(HOTKEYF_CONTROL<<8))!=0;
				bool bAlt1=(pTlsData->bho->m_UpHotkey&(HOTKEYF_ALT<<8))!=0;
				bool bShift2=GetKeyState(VK_SHIFT)<0;
				bool bCtrl2=GetKeyState(VK_CONTROL)<0;
				bool bAlt2=GetKeyState(VK_MENU)<0;
				if (bShift1==bShift2 && bAlt1==bAlt2)
				{
					if (bCtrl1==bCtrl2)
					{
						pTlsData->bho->m_pBrowser->BrowseObject(NULL,SBSP_SAMEBROWSER|SBSP_PARENT);
						return 1;
					}
					else if (bCtrl2)
					{
						pTlsData->bho->m_pBrowser->BrowseObject(NULL,SBSP_NEWBROWSER|SBSP_PARENT);
						return 1;
					}
				}
			}
		}
	}
	return CallNextHookEx(NULL,nCode,wParam,lParam);
}

bool CExplorerBHO::GetStatusText( wchar_t *buf, int size, const wchar_t *oldText, bool bShowTip, bool bShowSpace )
{
	bool res=false;
	CComPtr<IShellView> pView;
	if (m_pBrowser && SUCCEEDED(m_pBrowser->QueryActiveShellView(&pView)))
	{
		CComQIPtr<IFolderView> pView2=pView;

		CComPtr<IPersistFolder2> pFolder;
		if (pView2 && SUCCEEDED(pView2->GetFolder(IID_IPersistFolder2,(void**)&pFolder)))
		{
			int count;
			if (bShowTip && SUCCEEDED(pView2->ItemCount(SVGIO_SELECTION,&count)) && count==1)
			{
				// if only one item is selected, show its info in the status bar
				CComPtr<IEnumIDList> pEnum;
				PITEMID_CHILD child;
				if (SUCCEEDED(pView2->Items(SVGIO_SELECTION,IID_IEnumIDList,(void**)&pEnum)) && pEnum && pEnum->Next(1,&child,NULL)==S_OK)
				{
					CComQIPtr<IShellFolder> pFolder2=pFolder;
					if (pFolder2)
					{
						CComPtr<IQueryInfo> pQueryInfo;
						if (SUCCEEDED(pFolder2->GetUIObjectOf(NULL,1,(PCUITEMID_CHILD*)&child,IID_IQueryInfo,NULL,(void**)&pQueryInfo)))
						{
							CComString pTip;
							if (SUCCEEDED(pQueryInfo->GetInfoTip(QITIPF_DEFAULT|QITIPF_SINGLELINE,&pTip)) && pTip)
							{
								Strcpy(buf,size,pTip);
								for (wchar_t *p=buf;*p;p++)
									if (*p=='\t')
										*p=' ';
								res=true;
							}
						}
					}
				}
			}

			if (!res)
			{
				wchar_t buf2[256];
				if (!oldText)
				{
					int count=-1;
					const wchar_t *fmt=NULL;
					if (SUCCEEDED(pView2->ItemCount(SVGIO_SELECTION,&count)) && count>0)
					{
						fmt=(count==1?FindTranslation(L"Status.ItemSelected",L"%s item selected"):FindTranslation(L"Status.ItemsSelected",L"%s items selected"));
					}
					else if (SUCCEEDED(pView2->ItemCount(SVGIO_ALLVIEW,&count)) && count>=0)
					{
						fmt=(count==1?FindTranslation(L"Status.Item",L"%s item"):FindTranslation(L"Status.Items",L"%s items"));
					}
					else
						buf2[0]=0;
					if (fmt)
					{
						wchar_t str1[100];
						wchar_t str2[100];
						Sprintf(str1,_countof(str1),L"%d",count);
						NUMBERFMT numFmt;
						wchar_t sep1[10], sep2[10];
						numFmt.NumDigits=0;
						GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_ILZERO,sep1,10);
						numFmt.LeadingZero=_wtol(buf);
						GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_INEGNUMBER,sep1,10);
						numFmt.NegativeOrder=_wtol(buf);
						GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_SGROUPING,sep1,10);
						numFmt.Grouping=0;
						for (const wchar_t *p=sep1;*p;p++)
							if (*p>='1' && *p<='9')
								numFmt.Grouping=numFmt.Grouping*10+(*p-'0');
						GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_SDECIMAL,sep1,10);
						numFmt.lpDecimalSep=sep1;
						GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_STHOUSAND,sep2,10);
						numFmt.lpThousandSep=sep2;

						if (GetNumberFormat(LOCALE_USER_DEFAULT,0,str1,&numFmt,str2,_countof(str2)))
							Sprintf(buf2,_countof(buf2),fmt,str2);
						else
							Sprintf(buf2,_countof(buf2),fmt,str1);
					}
					res=true;
				}
				if (bShowSpace)
				{
					// show the free space of the drive containing the current folder
					// also works for network locations
					CAbsolutePidl pidl;
					wchar_t path[_MAX_PATH];
					ULARGE_INTEGER diskSize;
					if (SUCCEEDED(pFolder->GetCurFolder(&pidl)) && SHGetPathFromIDList(pidl,path) && GetDiskFreeSpaceEx(path,NULL,NULL,&diskSize))
					{
						wchar_t str[100];
						StrFormatByteSize64(diskSize.QuadPart,str,_countof(str));
						Sprintf(buf,size,FindTranslation(L"Status.FreeSpace",L"%s (Disk free space: %s)"),oldText?oldText:buf2,str);
						res=true;
					}
					else if (!oldText)
						Strcpy(buf,size,buf2);
				}
				else if (!oldText)
					Strcpy(buf,size,buf2);
			}
		}
	}
	return res;
}

void CExplorerBHO::GetFileSize( wchar_t *buf, int size )
{
	__int64 fileSize=-1;
	CComPtr<IShellView> pView;
	bool bMore=false;
	int time0=GetTickCount();
	if (m_pBrowser && SUCCEEDED(m_pBrowser->QueryActiveShellView(&pView)))
	{
		CComQIPtr<IFolderView> pView2=pView;
		CComPtr<IPersistFolder2> pFolder;
		CAbsolutePidl pidl;
		if (pView2 && SUCCEEDED(pView2->GetFolder(IID_IPersistFolder2,(void**)&pFolder)) && SUCCEEDED(pFolder->GetCurFolder(&pidl)))
		{
			CComQIPtr<IShellFolder2> pFolder2=pFolder;
			UINT type=SVGIO_SELECTION;
			int count, selCount;
			if (SUCCEEDED(pView2->ItemCount(SVGIO_ALLVIEW,&count)))
			{
				if ((FAILED(pView2->ItemCount(SVGIO_SELECTION,&selCount)) || selCount==0))
					type=SVGIO_ALLVIEW;
				CComPtr<IEnumIDList> pEnum;
				if ((count<10000 || selCount<1000) && SUCCEEDED(pView2->Items(type,IID_IEnumIDList,(void**)&pEnum)) && pEnum)
				{
					PITEMID_CHILD child;
					SHCOLUMNID column={PSGUID_STORAGE,PID_STG_SIZE};
					int index=0;
					while (pEnum->Next(1,&child,NULL)==S_OK)
					{
						index++;
						if ((index%100)==0 && (GetTickCount()-time0)>500)
						{
							ILFree(child);
							bMore=true;
							break;
						}
						CComVariant var;
						if (SUCCEEDED(pFolder2->GetDetailsEx(child,&column,&var)) && var.vt==VT_UI8)
						{
							if (fileSize<0)
								fileSize=var.ullVal;
							else
								fileSize+=var.ullVal;
						}
						ILFree(child);
					}
				}
			}
		}
	}
	if (fileSize>=0)
	{
		// format the file size as KB, MB, etc
		StrFormatByteSize64(fileSize,buf,size);
		if (bMore)
			Strcat(buf,size,L"+");
	}
	else
		buf[0]=0;
}

// Subclass the statusbar to:
//   - show free disk space
//   - show the total size of the selected files
LRESULT CALLBACK CExplorerBHO::SubclassStatusProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	wchar_t buf[1024];
	if (uMsg==WM_CLEAR)
	{
		// recalculate the selection size on a timer. this way if the status text is changed frequently
		// the recalculation will not happen every time
		SetTimer(hWnd,uIdSubclass,10,NULL);
	}
	if (uMsg==WM_PAINT && ((CExplorerBHO*)uIdSubclass)->m_bForceRefresh)
	{
		// sometimes Explorer doesn't fully initialize the status bar on Windows 7 and leaves it with 1 part
		// in such case force the view to refresh after the status bar is fully visible
		((CExplorerBHO*)uIdSubclass)->m_bForceRefresh=false;
		if (SendMessage(hWnd,SB_GETPARTS,0,0)<=1)
			PostMessage(GetParent(hWnd),WM_COMMAND,41504,0); // Refresh command
	}
	if (uMsg==SB_SETTEXT && LOWORD(wParam)==0)
	{
		// when the text of the first part is changing
		if (dwRefData&SHOW_FREE_SPACE)
		{
			if (((CExplorerBHO*)uIdSubclass)->m_bResetStatus && SendMessage(hWnd,SB_GETPARTS,0,0)<=1)
			{
				// HACK! there is a bug in Win7 and when the Explorer window is created it doesn't correctly
				// initialize the status bar to have 3 parts. as soon as the user resizes the window the
				// 3 parts appear. so here we resize the parent of the status bar to create the 3 parts.
				HWND parent=GetParent(hWnd);
				RECT rc;
				GetWindowRect(parent,&rc);
				SetWindowPos(parent,NULL,0,0,rc.right-rc.left+1,rc.bottom-rc.top,SWP_NOZORDER|SWP_NOMOVE);
				SetWindowPos(parent,NULL,0,0,rc.right-rc.left,rc.bottom-rc.top,SWP_NOZORDER|SWP_NOMOVE);
				// the first time the status text is set it is too early. so we do this until we get at lest 2 parts
				if (SendMessage(hWnd,SB_GETPARTS,0,0)>1)
					((CExplorerBHO*)uIdSubclass)->m_bResetStatus=false;
			}
		}
		if (((CExplorerBHO*)uIdSubclass)->GetStatusText(buf,_countof(buf),(wchar_t*)lParam,(dwRefData&SHOW_INFOTIP)!=0,(dwRefData&SHOW_FREE_SPACE)!=0))
			lParam=(LPARAM)buf;
	}
	if (uMsg==SB_SETTEXT && LOWORD(wParam)==1)
	{
		return 0;
	}

	if (uMsg==WM_TIMER && wParam==uIdSubclass)
	{
		// recalculate the total size of the selected files and show it in part 2 of the status bar
		KillTimer(hWnd,wParam);
		((CExplorerBHO*)uIdSubclass)->GetFileSize(buf,_countof(buf));
		DefSubclassProc(hWnd,SB_SETTEXT,1,(LPARAM)buf);
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

LRESULT CALLBACK CExplorerBHO::SubclassStatusProc8( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	wchar_t buf[1024];
	if (uMsg==WM_CLEAR)
	{
		// recalculate the selection size on a timer. this way if the status text is changed frequently
		// the recalculation will not happen every time
		SetTimer(hWnd,uIdSubclass,10,NULL);

		if (!((CExplorerBHO*)uIdSubclass)->GetStatusText(buf,_countof(buf),NULL,(dwRefData&SHOW_INFOTIP)!=0,(dwRefData&SHOW_FREE_SPACE)!=0))
			buf[0]=0;
		SendMessage(hWnd,SB_SETTEXT,PART_TEXT,(LPARAM)buf);
		return 0;
	}
	if (uMsg==WM_TIMER && wParam==uIdSubclass)
	{
		// recalculate the total size of the selected files and show it in part 2 of the status bar
		KillTimer(hWnd,wParam);
		((CExplorerBHO*)uIdSubclass)->GetFileSize(buf,_countof(buf));
		SendMessage(hWnd,SB_SETTEXT,PART_SIZE,(LPARAM)buf);
		return 0;
	}
	if (uMsg==WM_LBUTTONDBLCLK)
	{
		POINT pt={(short)LOWORD(lParam),(short)HIWORD(lParam)};
		RECT rc;
		DefSubclassProc(hWnd,SB_GETRECT,PART_ZONE,(LPARAM)&rc);
		if (PtInRect(&rc,pt))
		{
			CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;
			CComBSTR url;
			if (pThis->m_pWebBrowser && SUCCEEDED(pThis->m_pWebBrowser->get_LocationURL(&url)))
			{
				// use undocumented function 383 from shlwapi
				typedef void (WINAPI* FZoneConfigureW)(HWND,LPCWSTR);
				FZoneConfigureW ZoneConfigureW;

				HMODULE	hShlwapi=LoadLibrary(L"shlwapi.dll");
				if(hShlwapi)
				{
					ZoneConfigureW=(FZoneConfigureW)GetProcAddress(hShlwapi,MAKEINTRESOURCEA(383));
					if(ZoneConfigureW)
						ZoneConfigureW(GetAncestor(hWnd,GA_ROOT),url);
					FreeLibrary(hShlwapi);
				}
			}
			return 0;
		}
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

// Subclass the DUIView to reduce its size and reposition the taskbar
LRESULT CALLBACK CExplorerBHO::SubclassDUIViewProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;
	if (uMsg==WM_WINDOWPOSCHANGING && pThis->m_Status8)
	{
		WINDOWPOS *pPos=(WINDOWPOS*)lParam;
		if (!(pPos->flags&SWP_NOSIZE))
		{
			RECT rc;
			GetWindowRect(pThis->m_Status8,&rc);
			int height=rc.bottom-rc.top;
			pPos->cy-=height;
			SetWindowPos(pThis->m_Status8,NULL,pPos->x,pPos->y+pPos->cy,pPos->cx,rc.bottom-rc.top,SWP_NOZORDER);
			int parts[]={pPos->cx-height-pThis->m_FileSizeWidth-pThis->m_ZoneWidth,pPos->cx-height-pThis->m_ZoneWidth,-1};
			SendMessage(pThis->m_Status8,SB_SETPARTS,pThis->m_ZoneWidth?3:2,(LPARAM)parts);
		}
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

// Subclass the rebar in the title bar to handle the title bar Up button
LRESULT CALLBACK CExplorerBHO::SubclassRebarProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	if (uMsg==WM_NOTIFY && ((NMHDR*)lParam)->hwndFrom==(HWND)dwRefData && ((NMHDR*)lParam)->code==NM_CUSTOMDRAW)
	{
		// custom-draw the toolbar. just draw the correct icon and nothing else
		NMTBCUSTOMDRAW *pDraw=(NMTBCUSTOMDRAW*)lParam;
		if (pDraw->nmcd.dwDrawStage==CDDS_PREPAINT)
			return CDRF_NOTIFYITEMDRAW;
		if (pDraw->nmcd.dwDrawStage==CDDS_ITEMPREPAINT)
		{
			CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;
			BOOL comp;
			if (SUCCEEDED(DwmIsCompositionEnabled(&comp)) && comp)
				FillRect(pDraw->nmcd.hdc,&pDraw->nmcd.rc,(HBRUSH)GetStockObject(BLACK_BRUSH));
			if (pDraw->nmcd.uItemState&CDIS_DISABLED)
			{
				if (pThis->m_IconDisabled)
					DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconDisabled,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
				else
					DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconNormal,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
			}
			else if (pDraw->nmcd.uItemState&CDIS_SELECTED)
			{
				if (pThis->m_IconPressed)
					DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconPressed,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
				else
					DrawIconEx(pDraw->nmcd.hdc,1,1,pThis->m_IconNormal,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
			}
			else if (pDraw->nmcd.uItemState&CDIS_HOT)
			{
				if (pThis->m_IconHot)
					DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconHot,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
				else
					DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconNormal,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
			}
			else
				DrawIconEx(pDraw->nmcd.hdc,0,0,pThis->m_IconNormal,0,0,0,NULL,DI_NORMAL|DI_NOMIRROR);
			return CDRF_SKIPDEFAULT;
		}
	}

	if (uMsg==WM_THEMECHANGED)
	{
		// the button size is reset when the theme changes. force the correct size again
		HWND toolbar=(HWND)dwRefData;
		RECT rc;
		GetClientRect(toolbar,&rc);
		PostMessage(toolbar,TB_SETBUTTONSIZE,0,MAKELONG(rc.right,rc.bottom));
	}

	if (uMsg==WM_NOTIFY && ((NMHDR*)lParam)->hwndFrom==(HWND)dwRefData && ((NMHDR*)lParam)->code==TBN_GETINFOTIP)
	{
		// show the tip for the up button
		NMTBGETINFOTIP *pTip=(NMTBGETINFOTIP*)lParam;
		Strcpy(pTip->pszText,pTip->cchTextMax,FindTranslation(L"Toolbar.GoUp",L"Up One Level"));
		return 0;
	}

	if (uMsg==WM_NOTIFY && ((NMHDR*)lParam)->hwndFrom==(HWND)dwRefData && ((NMHDR*)lParam)->code==NM_RCLICK)
	{
		NMMOUSE *pInfo=(NMMOUSE*)lParam;
		POINT pt=pInfo->pt;
		ClientToScreen(pInfo->hdr.hwndFrom,&pt);
		ShowSettingsMenu(hWnd,pt.x,pt.y);
		return TRUE;
	}

	if (uMsg==WM_COMMAND && wParam==1)
	{
		UINT flags=(GetKeyState(VK_CONTROL)<0?SBSP_NEWBROWSER:SBSP_SAMEBROWSER);
		((CExplorerBHO*)uIdSubclass)->m_pBrowser->BrowseObject(NULL,flags|SBSP_PARENT);
	}

	CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;
	if (pThis->m_bRemapBands)
	{
		// HACK! Explorer doesn't use RB_IDTOINDEX every time it needs to access a particular band. Since we insert the Up button in the second
		// position, the rest of the bands get offset and comedy ensues (the search box is not sized properly).
		// To fix the issue, we renumber the bands so that from the outside ours appears to be last.
		static int remapNewOld[2][4]={{3,0,1,2},{0,3,1,2}};
		static int remapOldNew[2][4]={{1,2,3,0},{0,2,3,1}};

		if (uMsg==RB_IDTOINDEX || uMsg==RB_HITTEST)
		{
			// remap the result from RB_IDTOINDEX and RB_HITTEST
			LRESULT res=DefSubclassProc(hWnd,uMsg,wParam,lParam);
			if (res<0 || res>3) return res;
			res=remapNewOld[pThis->m_UpButtonIndex-1][res];
			if (lParam && uMsg==RB_HITTEST) ((RBHITTESTINFO*)lParam)->iBand=(int)res;
			return res;
		}
		if (uMsg==RB_GETBANDBORDERS || uMsg==RB_GETBANDINFO || uMsg==RB_GETRECT || uMsg==RB_SETBANDINFO || uMsg==RB_SETBANDWIDTH)
		{
			// remap wParam for all GET/SET messages
			if (wParam>=0 && wParam<=3)
				wParam=remapOldNew[pThis->m_UpButtonIndex-1][wParam];
		}
	}

	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

// Subclass the breadcrumbs to make them show the full path
LRESULT CALLBACK CExplorerBHO::SubclassBreadcrumbProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;
	if (*pThis->m_CurPath)
	{
		if (uMsg==WM_SETFOCUS)
		{
			if (wParam)
			{
				// see if the focus comes from the combo box. if so, most likely Escape was pressed, so just focus the main frame
				HWND from=(HWND)wParam;
				HWND combo=FindChildWindow(GetParent(GetParent(hWnd)),WC_COMBOBOXEX);
				if (combo && (combo==from || IsChild(combo,from)))
				{
					SetFocus(GetAncestor(hWnd,GA_ROOT));
					return 0;
				}
			}
			// when the breadcrumbs are focused, switch to the combobox by simulating a mouse click
			RECT rc;
			GetClientRect(hWnd,&rc);
			LPARAM pos=MAKELONG(rc.right-1,rc.bottom/2);
			DefSubclassProc(hWnd,WM_LBUTTONDOWN,MK_LBUTTON,pos);
			DefSubclassProc(hWnd,WM_LBUTTONUP,0,pos);
			return 0;
		}
		if (uMsg==WM_LBUTTONDOWN || uMsg==WM_LBUTTONDBLCLK || uMsg==WM_LBUTTONUP)
		{
			// unless the mouse is clicked on the icon, replace the mouse position with a point on the far right.
			// this will cause Explorer to switch to the combobox even when a breadcrumb is clicked
			int iconSize=GetSystemMetrics(SM_CXSMICON);
			if (!pThis->m_CurIcon || (short)LOWORD(lParam)>iconSize+3)
			{
				RECT rc;
				GetClientRect(hWnd,&rc);
				lParam=MAKELONG(rc.right-1,rc.bottom/2);
			}
		}

		if (uMsg==WM_PAINT)
		{
			// make the breadcrumbs control draw the full path like the XP address bar
			RECT rc;
			GetClientRect(hWnd,&rc);

			PAINTSTRUCT ps;
			HDC hdc=BeginPaint(hWnd,&ps);

			// we need to use buffered painting because DrawThemeTextEx with DTT_COMPOSITED requires it
			// on Vista DTT_COMPOSITED is required so that the black text doesn't get transparent. On Windows 7 regular DrawText seems to work fine
			BP_PAINTPARAMS paintParams={sizeof(paintParams)};
			paintParams.dwFlags=BPPF_ERASE;
			HDC hdcPaint=NULL;
			HPAINTBUFFER hBufferedPaint=BeginBufferedPaint(hdc,&rc,BPBF_TOPDOWNDIB,&paintParams,&hdcPaint);
			if (hdcPaint)
			{
				rc.top++;
				SendMessage(GetParent(GetParent(hWnd)),WM_PRINTCLIENT,(WPARAM)hdcPaint,PRF_CLIENT);

				// draw icon
				int iconSize=GetSystemMetrics(SM_CXSMICON);
				if (pThis->m_CurIcon)
					DrawIconEx(hdcPaint,rc.left+3,(rc.top+rc.bottom-iconSize)/2,pThis->m_CurIcon,iconSize,iconSize,0,NULL,DI_NORMAL);
				rc.left+=iconSize+8; // Not a good idea to hard-code number of pixels, but seems to work fine for different DPI settings

				// draw path
				HFONT font=(HFONT)SendMessage(hWnd,WM_GETFONT,0,0);
				HGDIOBJ font0=SelectObject(hdcPaint,font);
				SetBkMode(hdcPaint,TRANSPARENT);
				SetTextColor(hdcPaint,GetSysColor(COLOR_WINDOWTEXT));
				HTHEME theme=GetWindowTheme(hWnd);
				BOOL dwm;
				if (theme && SUCCEEDED(DwmIsCompositionEnabled(&dwm)) && dwm)
				{
					DTTOPTS opts={sizeof(opts),DTT_COMPOSITED|DTT_TEXTCOLOR};
					opts.crText=GetSysColor(COLOR_WINDOWTEXT);
					DrawThemeTextEx(theme,hdcPaint,0,0,pThis->m_CurPath,-1,DT_NOPREFIX|DT_VCENTER|DT_SINGLELINE,&rc,&opts);
				}
				else
				{
					DrawText(hdcPaint,pThis->m_CurPath,-1,&rc,DT_NOPREFIX|DT_VCENTER|DT_SINGLELINE);
				}
				SelectObject(hdcPaint,font0);
				EndBufferedPaint(hBufferedPaint,TRUE);
			}
			EndPaint(hWnd,&ps);
			return 0;
		}
	}
	return DefSubclassProc(hWnd,uMsg,wParam,lParam);
}

// Subclass the progress bar behind the address bar to remove the history and replace it with a list of parent folders
LRESULT CALLBACK CExplorerBHO::SubclassProgressProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData )
{
	CExplorerBHO *pThis=(CExplorerBHO*)uIdSubclass;

	if (uMsg==WM_PARENTNOTIFY && LOWORD(wParam)==WM_CREATE && !pThis->m_ComboBox.m_hWnd)
	{
		// on Windows 7 the combobox is not created at startup. so listen for child windows being created and update pThis->m_ComboBox
		HWND combo=(HWND)lParam;
		wchar_t className[256];
		GetClassName(combo,className,_countof(className));
		if (_wcsicmp(className,WC_COMBOBOXEX)==0)
			pThis->m_ComboBox=combo;
	}

	if (uMsg==WM_COMMAND && (HWND)lParam==pThis->m_ComboBox.m_hWnd)
	{
		if (HIWORD(wParam)==CBN_DROPDOWN)
		{
			// on drop down refresh the list
			pThis->ClearComboItems();

			CComPtr<IShellFolder> pDesktop;
			SHGetDesktopFolder(&pDesktop);

			{
				// add desktop
				ITEMIDLIST shEmpty={{0}};
				CComString pName;
				if (SUCCEEDED(SHGetNameFromIDList((PIDLIST_ABSOLUTE)&shEmpty,SIGDN_DESKTOPABSOLUTEEDITING,&pName)))
				{
					ComboItem item={ILCloneFull((PIDLIST_ABSOLUTE)&shEmpty),0,CString(pName)};
					pThis->m_ComboItems.push_back(item);
				}
			}

			if (dwRefData==2)
			{
				// enumerate all desktop items
				CComPtr<IEnumIDList> pEnum;
				if (SUCCEEDED(pDesktop->EnumObjects(NULL,SHCONTF_FOLDERS,&pEnum)) && pEnum)
				{
					PITEMID_CHILD child;
					while (pEnum->Next(1,&child,NULL)==S_OK)
					{
						STRRET str;
						if (SUCCEEDED(pDesktop->GetDisplayNameOf(child,SHGDN_INFOLDER|SHGDN_NORMAL,&str)))
						{
							CComString pName;
							StrRetToStr(&str,child,&pName);
							ComboItem item={(PIDLIST_ABSOLUTE)child,1,CString(pName)};
							item.sortName=item.name;
							pThis->m_ComboItems.push_back(item);
						}
						else
							ILFree(child);
					}
				}

				// sort desktop items
				std::sort(pThis->m_ComboItems.begin()+1,pThis->m_ComboItems.end());
			}

			if (dwRefData==2)
			{
				// enumerate all computer items
				CAbsolutePidl pidlComp;
				SHGetKnownFolderIDList(FOLDERID_ComputerFolder,0,NULL,&pidlComp);
				int index=1;
				for (int i=1;i<(int)pThis->m_ComboItems.size();i++)
					if (ILIsEqual(pidlComp,pThis->m_ComboItems[i].pidl))
					{
						index=i+1;
						break;
					}
				int index0=index;
				CComPtr<IShellFolder> pComputer;
				pDesktop->BindToObject(pidlComp,NULL,IID_IShellFolder,(void**)&pComputer);

				CComPtr<IEnumIDList> pEnum;
				if (pComputer && SUCCEEDED(pComputer->EnumObjects(NULL,SHCONTF_FOLDERS,&pEnum)) && pEnum)
				{
					PITEMID_CHILD child;
					while (pEnum->Next(1,&child,NULL)==S_OK)
					{
						STRRET str;
						if (SUCCEEDED(pComputer->GetDisplayNameOf(child,SHGDN_INFOLDER|SHGDN_NORMAL,&str)))
						{
							CComString pName;
							StrRetToStr(&str,child,&pName);
							ComboItem item={ILCombine(pidlComp,child),2,CString(pName)};
							pThis->m_ComboItems.insert(pThis->m_ComboItems.begin()+index,1,item);
							index++;
						}
						ILFree(child);
					}
				}

				//sort computer items
				std::sort(pThis->m_ComboItems.begin()+index0,pThis->m_ComboItems.begin()+index);
			}

			if (pThis->m_CurPidl)
			{
				// enumerate all parent items
				CAbsolutePidl pidl(pThis->m_CurPidl);
				PIDLIST_ABSOLUTE pidlStart=pidl;
				int index=0;
				for (int i=0;i<(int)pThis->m_ComboItems.size();i++)
				{
					PIDLIST_ABSOLUTE p=(PIDLIST_ABSOLUTE)ILFindChild(pThis->m_ComboItems[i].pidl,pidl);
					if (p)
					{
						index=i;
						pidlStart=p;
					}
				}
				int n=0;
				for (PUIDLIST_RELATIVE child=pidl;!ILIsEmpty(child);child=ILGetNext(child))
					n++;

				int start=n;
				for (PUIDLIST_RELATIVE child=pidlStart;!ILIsEmpty(child);child=ILGetNext(child))
					start--;

				for (int i=start;i<n;i++)
				{
					wchar_t *pName=NULL;
					CComPtr<IShellFolder> pFolder;
					PCITEMID_CHILD child;
					if (SUCCEEDED(SHBindToParent(pidl,IID_IShellFolder,(void**)&pFolder,&child)))
					{
						STRRET str;
						if (SUCCEEDED(pFolder->GetDisplayNameOf(child,SHGDN_INFOLDER|SHGDN_NORMAL,&str)))
						{
							CComString pName;
							StrRetToStr(&str,child,&pName);
							ComboItem item={ILCloneFull(pidl),n-(i-start),CString(pName)};
							pThis->m_ComboItems.insert(pThis->m_ComboItems.begin()+index+1,1,item);
						}
					}
					ILRemoveLastID(pidl);
				}
			}

			// add all sorted items to the combobox
			COMBOBOXEXITEM item={CBEIF_TEXT|CBEIF_IMAGE|CBEIF_SELECTEDIMAGE|CBEIF_INDENT|CBEIF_LPARAM};
			item.iItem=-1;
			for (std::vector<ComboItem>::const_iterator it=pThis->m_ComboItems.begin();it!=pThis->m_ComboItems.end();++it)
			{
				item.iImage=item.iSelectedImage=-1;
				item.pszText=(LPWSTR)(LPCWSTR)it->name;
				item.iIndent=it->indent;
				item.lParam=(LPARAM)it->pidl;
				SHFILEINFO info;
				if (SHGetFileInfo((LPCTSTR)it->pidl,0,&info,sizeof(info),SHGFI_PIDL|SHGFI_SYSICONINDEX|SHGFI_SMALLICON))
					item.iImage=item.iSelectedImage=info.iIcon;
				int idx=(int)pThis->m_ComboBox.SendMessage(CBEM_INSERTITEM,'CLSH',(LPARAM)&item);
				if (pThis->m_CurPidl && ILIsEqual(it->pidl,pThis->m_CurPidl))
					pThis->m_ComboBox.SendMessage(CB_SETCURSEL,idx);
			}

			return 0;
		}
		if (HIWORD(wParam)==CBN_CLOSEUP || HIWORD(wParam)==CBN_SELENDCANCEL)
		{
			// on close clear the list
			if (!pThis->m_ComboItems.empty())
			{
				pThis->m_ComboBox.SetWindowText(pThis->m_CurPath);
				pThis->ClearComboItems();
			}
			if (HIWORD(wParam)==CBN_SELENDCANCEL)
				PostMessage(hWnd,pThis->m_NavigateMsg,1,0);
			return 0;
		}
		if (HIWORD(wParam)==CBN_SELENDOK)
		{
			// when an item is selected, go to it and clear the list (selection with mouse)
			int index=(int)pThis->m_ComboBox.SendMessage(CB_GETCURSEL);
			if (index>=0)
			{
				COMBOBOXEXITEM item={CBEIF_LPARAM,index};
				pThis->m_ComboBox.SendMessage(CBEM_GETITEM,0,(LPARAM)&item);
				pThis->m_NavigatePidl.Clone((PIDLIST_ABSOLUTE)item.lParam);
				PostMessage(hWnd,pThis->m_NavigateMsg,0,0);
			}
			pThis->ClearComboItems();