Option Explicit

Dim arrFound, arrInt, arrPath, arrPathExt, arrTemp
Dim blnAll, blnClipboard, blnExtOnly, blnHasExt, blnQuiet, blnShort, blnVer
Dim i, intArgs, j
Dim objFile, objFSO, objIE, wshShell
Dim strComSpec, strExt, strIntAll, strIntCmd, strIntCom, strPath, strPathExt, strResult, strTime, strVer

' Initialize variables
intArgs   = 0
strResult = ""

With WScript.Arguments
	' Check the command line for exactly 1 argument (the file
	' name), which should NOT contain wildcard characters
	If .Unnamed.Count   <>   1   Then Syntax
	If InStr( .Unnamed(0), "*" ) Then Syntax
	If InStr( .Unnamed(0), "?" ) Then Syntax
	' Check the command line switches
	If .Named.Exists( "A" ) Then
		blnAll  = True
		intArgs = intArgs + 1
	Else
		blnAll  = False
	End If
	If .Named.Exists( "C" ) Then
		blnClipboard = True
		intArgs      = intArgs + 1
	Else
		blnClipboard = False
	End If
	If .Named.Exists( "Q" ) Then
		' /Q can only be used with /C
		If blnClipboard Then
			blnQuiet = True
			intArgs  = intArgs + 1
		Else
			Syntax
		End If
	Else
		blnQuiet = False
	End If
	If .Named.Exists( "S" ) Then
		blnShort = True
		intArgs  = intArgs + 1
	Else
		blnShort = False
	End If
	If .Named.Exists( "V" ) Then
		blnVer  = True
		intArgs = intArgs + 1
	Else
		blnVer  = False
	End If
	If .Named.Exists( "X" ) Then
		blnExtOnly = True
		intArgs    = intArgs + 1
	Else
		blnExtOnly = False
	End If
	' Check for remaining invalid command line switches
	If intArgs <> .Named.Count Then Syntax
End With

' Create the required objects
Set objFSO   = CreateObject( "Scripting.FileSystemObject" )
Set wshShell = CreateObject( "Wscript.Shell" )

' Define internal command lists
strIntAll = "BREAK CALL CD CHCP CHDIR CLS COPY DATE DEL DIR ECHO ERASE " _
          & "EXIT FOR GOTO IF MD MKDIR MOVE PATH PAUSE PROMPT RD REM " _
          & "REN RENAME RMDIR SET SHIFT TIME TYPE VER VERIFY VOL "
strIntCmd = "ASSOC COLOR ENDLOCAL FTYPE POPD PUSHD SETLOCAL START TITLE"
strIntCom = "CTTY LFNFOR LH LOADHIGH LOCK TRUENAME UNLOCK"

' Determine the type of command processor
' used: COMMAND.COM or CMD.EXE
strComSpec = UCase( wshShell.ExpandEnvironmentStrings( "%COMSPEC%" ) )
If Right( strComSpec, 12 ) = "\COMMAND.COM" Then
	arrInt = Split( strIntAll & strIntCom )
End If
If Right( strComSpec, 8 ) = "\CMD.EXE" Then
	arrInt = Split( strIntAll & strIntCmd )
End If

' Read the PATH and PATHEXT variables, and store their values in
' arrays; the current directory is prepended to the PATH first
strPath    = wshShell.CurrentDirectory & ";" _
           & wshShell.ExpandEnvironmentStrings( "%PATH%" )
strPathExt = wshShell.ExpandEnvironmentStrings( "%PATHEXT%" )
arrPath    = Split( strPath, ";" )
arrPathExt = Split( strPathExt, ";" )

' Check if the command line argument contains a dot
' which would mean we wouldn't have to use PATHEXT
blnHasExt = CBool( InStr( WScript.Arguments.Unnamed(0), "." ) > 0 )

If blnHasExt Then
	' If an extension WAS specified, just search the PATH
	strExt     = Mid( WScript.Arguments.Unnamed(0), InStrRev( WScript.Arguments.Unnamed(0), "." ) )
	arrPathExt = Array( strExt )
	strResult  = FindWhich( WScript.Arguments.Unnamed(0) )
Else
	If IsArray( arrInt ) And Not blnExtOnly Then
		' Let's check for INTERNAL commands first, unless of course, the /X switch was used
		For i = 0 To UBound( arrInt )
			If UCase( WScript.Arguments.Unnamed(0) ) = arrInt(i) Then
				strResult = "[" & wshShell.ExpandEnvironmentStrings( "%COMSPEC%" ) & "]::" & arrInt(i)
				Exit For
			End If
		Next
	End If
	If strResult = "" Then
		strResult = FindWhich( WScript.Arguments.Unnamed(0) )
	End If
End If

' Copy the result to clipboard if the /C command line switch was used
If blnClipboard Then
	Set objIE = CreateObject( "InternetExplorer.Application" )
	objIE.Navigate( "about:blank" )
	objIE.Document.ParentWindow.ClipboardData.SetData "text", strResult
	objIE.Quit
	Set objIE = Nothing
End If

' Display the result, unless the /Q command line switch was used
If Not blnQuiet Then
	WScript.Echo strResult
End If

' Return code 1 if not found
WScript.Quit -( strResult = "" )


Function FindWhich( myFile )
	' This function searches the directories in the PATH array for the
	' specified file name, adding extensions from PATHEXT if required
	Dim i, j, objFound, strFound, strFullPath, strTestPath
	strFound = ""
	For i = 0 To UBound( arrPath )
		' Skip empty directory values, caused by the PATH
		' variable being terminated with a semicolon
		If Trim( arrPath(i) ) <> "" Then
			' Iterate through the array with extensions (if an extension was specified,
			' the array will only contain the specified extension, otherwise it will
			' contain all extensions in PATHEXT)
			For j = 0 To UBound( arrPathExt )
				' Build a fully qualified path of the file to test for
				strTestPath = objFSO.BuildPath( arrPath(i), objFSO.GetBaseName( myFile ) & arrPathExt(j) )
				' Check if that file exists
				If objFSO.FileExists( strTestPath ) Then
					Set objFound = objFSO.GetFile( strTestPath )
					If blnVer Then
						strVer = objFSO.GetFileVersion( strTestPath )
						If strVer = "" Then
							strVer = objFound.DateLastModified
						End If
					End If
					If blnShort Then
						' Get the capitalization right
						strTestPath  = objFSO.GetAbsolutePathName( strTestPath )
						' Return the short full path
						strFullPath  = objFound.ShortPath
					Else
						' Return the full path with proper capitalization
						strFullPath = objFSO.GetAbsolutePathName( strTestPath )
					End If
					If blnAll Then
						' Append the path of the file found
						strFound = strFound & strFullPath
						If blnVer Then strFound = strFound & vbTab & strVer
						strFound = strFound & ";"
					Else
						' Abort when the first file is found
						strFound = strFullPath
						If blnVer Then strFound = strFound & vbTab & strVer
						Exit For
					End If
					Set objFound = Nothing
					' Unless the /A (All) command line switch was used, abort inner loop after the first file is found
					If strFound <> "" And Not blnAll Then Exit For
				End If
			Next
		End If
		' Unless the /A (All) command line switch was used, abort outer loop after the first file is found
		If strFound <> "" And Not blnAll Then Exit For
	Next
	If strFound <> "" Then
		arrFound = Split( strFound, ";" )
		strFound = Join( arrFound, vbCrLf )
	End If
	FindWhich = strFound
End Function


Sub Syntax( )
	Dim strMsg
	strMsg = vbCrLf _
	       & "Which.vbs,  Version 1.20" & vbCrLf _
	       & "Find out which file or internal command is actually executed when you type" _
	       & vbCrLf _
	       & "a command without its fully qualified path (like UNIX command, but extended)" _
	       & vbCrLf & vbCrLf _
	       & "Usage:  WHICH.VBS  filename[.ext]  [ /A ]  [ /C [ /Q ] ]  [/S]  [/V]  [/X]" _
	       & vbCrLf & vbCrLf _
	       & "Where:  filename[.ext]  file name (with optional extension) or internal command" _
	       & vbCrLf _
	       & "                        to search for; wildcards (""*"" and ""?"") are not allowed;" _
	       & vbCrLf _
	       & "                        use the extension to search for .dll, .ocx, .ps1, etc." _
	       & vbCrLf _
	       & "        /A              list All matches, not just the first match" _
	       & vbCrLf _
	       & "        /C              copy result to the Clipboard" _
	       & vbCrLf _
	       & "        /Q              Quiet mode, no screen output (only valid with /C)" _
	       & vbCrLf _
	       & "        /S              return Short path(s) (8.3 notation)" _
	       & vbCrLf _
	       & "        /V              show Version number" _
	       & vbCrLf _
	       & "        /X              eXternal commands only, ignore internal commands" _
	       & vbCrLf & vbCrLf _
	       & "Notes:  /A and /V switches will be ignored for internal commands" _
	       & vbCrLf _
	       & "        /V will display file timestamp for non-executables" _
	       & vbCrLf & vbCrLf _
	       & "Written by Rob van der Woude" & vbCrLf _
	       & "http://www.robvanderwoude.com" & vbCrLf
	WScript.Echo strMsg
	WScript.Quit 1
End Sub