# //***************************************************************************
# // Created by: Henk Hofs
# //
# // Microsoft Deployment Toolkit Solution Accelerator
# // 
# // File: MDT-ZTI.ps1
# //
# // Version: 1.0
# //
# // Purpose: Provide ZTI Functionality to MDT without the use of SCCM/SMS.
# //
# // Usage: powershell.exe -command MDT-ZTI.ps1
# //
# // History:
# // Version	Author		Notes
# // 0.7		HHO			Initial version
# // 0.8		HHO			Added SQL Invoke-command function from the Powershell Cookbook by Lee Holmes
# // 0.9		HHO			Added Remove-netBootComputer account to fully clear PXE data on computers							
# // 1.0		HHO			Final version		
# //*************************************************************************** 

# //*************************************************************************** 
# // Configuration:
# // Notes: Set the database name and datasource for your environment heren.
# // For SQLEXPRESS on the same server use ".\SQLEXPRESS" as datasource
# //*************************************************************************** 
	$Database = "MDT_DB"
	$DataSource = ".\SQLEXPRESS"


# //----------------------------------------------------------------------------
# //  Function: AD\Remove-netBootComputerAccount
# //  Purpose: Removes the DomainAdmins(n) computer account from AD to reset the PXE request
# //----------------------------------------------------------------------------
	Function Global:AD\Remove-netBootComputerAccount ([string]$UUID) {
		$strFilter = "(&(objectCategory=Computer))"
		$objDomain = New-Object System.DirectoryServices.DirectoryEntry
		$objSearcher = New-Object System.DirectoryServices.DirectorySearcher
		$objSearcher.SearchRoot = $objDomain
		$objSearcher.PageSize = 1000
		$objSearcher.Filter = $strFilter
		$objSearcher.SearchScope = "Subtree"
		$colResults = $objSearcher.FindAll()
		ForEach ($objResult in $colResults) {
			If ($objResult.Properties.netbootguid -ne $Null) {
				$netbootguid = $objResult.GetDirectoryEntry().netbootguid
				$netbootguid = $netbootguid.ToString()
				$netbootguid.split(" ") | ForEach-Object {
					[int]$netbootguid = $_ 
					$strNetboot = [Convert]::ToString($netbootguid, 16)
					If ($strNetboot.length -eq 1) {$strNetboot = $strNetboot.Insert(0, "0")}
					$strNetbootNew = $strNetbootNew + $strNetboot
					}
			
				If ($strNetBootNew.ToUpper() -eq $UUID) {
				$DN = $objResult.GetDirectoryEntry().distinguishedName
				dsrm.exe -noprompt "$DN" 
				}			
			}
		}
	}
	
	

# //----------------------------------------------------------------------------
# //  Function: SQL\Invoke-Command
# //  Purpose: Invoke a command in SQL syntax
# //  Notes: From Windows PowerShell Cookbook (O'Reilly)
# //		 by Lee Holmes (http://www.leeholmes.com/guide)
# //----------------------------------------------------------------------------
Function Global:SQL\Invoke-Command ([string] $DataSource, [string] $Database, [string] $SQLCommand, [System.Management.Automation.PsCredential] $Credential) {
	# // Prepare the authentication information. By default, we pick Windows authentication
	$authentication = "Integrated Security=SSPI;"
	
	# // If the user supplies a credential, then they want SQL authentication
	if($credential)
	{
		$plainCred = $credential.GetNetworkCredential()
		$authentication = 
			("uid={0};pwd={1};" -f $plainCred.Username,$plainCred.Password)
	}
	
	# // Prepare the connection string out of the information they provide
	$connectionString = "Provider=sqloledb; " +
						"Data Source=$dataSource; " +
						"Initial Catalog=$database; " +
						"$authentication; "
	
	# // Connect to the data source and open it
	$connection = New-Object System.Data.OleDb.OleDbConnection $connectionString
	$command = New-Object System.Data.OleDb.OleDbCommand $sqlCommand,$connection
	$connection.Open()
	
	# // Fetch the results, and close the connection
	$adapter = New-Object System.Data.OleDb.OleDbDataAdapter $command
	$dataset = New-Object System.Data.DataSet
	[void] $adapter.Fill($dataSet)
	$connection.Close()
	
	# // Return the dataset
	Return $dataset
	}



# //----------------------------------------------------------------------------
# //  Function: ZTI\Process-PendingDevicesData
# //  Purpose: Process the data to a usable format.
# //----------------------------------------------------------------------------
	Function Global:ZTI\Process-PendingDevicesData([hashtable]$PendingDevices, [int]$i) {
		$UUIDRaw = $PendingDevices.GetEnumerator() | Where-Object {$_.Value -eq $i -and $_.Key -match "UUID*"} | Select-Object Key 
		$MACAddressRaw =  $PendingDevices.GetEnumerator() | Where-Object {$_.Value -eq $i -and $_.Key -match "MAC address"} | Select-Object Key
		$RequestIDRaw =  $PendingDevices.GetEnumerator() | Where-Object {$_.Value -eq $i -and $_.Key -match "Request*"} | Select-Object Key 
		[string]$UUID = $UUIDRaw.Key
		[string]$MACAddress = $MACAddressRaw.Key
		[string]$RequestID = $RequestIDRaw.Key
		$UUID = $UUID.Split(":") | Select-Object -Last 1
		$UUID = $UUID.TrimStart()
		$MACAddress = $MACAddress.Split(":") | Select-Object -Last 1
		$MACAddress = $MACAddress.TrimStart()
		$MACAddress = $MACAddress.Substring(20)
		$MACAddress = $MACAddress.Insert(2, ":");$MACAddress = $MACAddress.Insert(5, ":");$MACAddress = $MACAddress.Insert(8, ":"); $MACAddress = $MACAddress.Insert(11, ":"); $MACAddress = $MACAddress.Insert(14, ":")
		$RequestID = $RequestID.Split(":") | Select-Object -Last 1
		$RequestID = $RequestID.TrimStart()
		
		Return @{"RequestID" = $RequestID; "MACAddress" = $MACAddress; "UUID" = $UUID}
		}
		
	
# //----------------------------------------------------------------------------
# //  Function: ZTI\Get-PendingDevices
# //  Purpose: Get the pending devices from WDS
# //----------------------------------------------------------------------------
	Function Global:ZTI\Get-PendingDevices() {
	ZTI\Write-Log -LogLevel "Information" -Description "Getting pending devices from WDS" -EventID 4006 -Source "WDS Server"
	$PendingDevices = wdsutil.exe /Get-AutoAddDevices /DeviceType:PendingDevices
	$PendingDevices = $PendingDevices | Where-Object {$_ -ne ""}
	[hashtable]$PendingHashTable = @{0 = 0}
	[int]$i = 0
	$PendingHashTable.Clear()
	
	$PendingDevices | ForEach-Object{
		if($_ -match "UUID*"){$PendingHashTable.Add($_, $i)}
		if($_ -match "MAC add*"){$PendingHashTable.Add($_, $i)}
		if($_ -match "Request*"){$i++;$PendingHashTable.Add($_, $i)}
		}
	$TotalPending = $PendingHashTable.Count / 3
	ZTI\Write-Log -LogLevel "Information" -Description "Found $TotalPending pending device(s)" -EventID 4007 -Source "WDS Server"
	Return $PendingHashTable

	}

# //----------------------------------------------------------------------------
# //  Function: ZTI\Write-Log
# //  Purpose: Write-Log entries to the event log and display on screen
# //----------------------------------------------------------------------------
	Function Global:ZTI\Write-Log ([string]$LogLevel, [string]$Description, [int]$EventID, [string]$Source) {
	Switch ($LogLevel) {
	"Error" {$ForegroundColor = "Red"}
	"Warning" {$ForegroundColor = "Yellow"}
	"Information" {$ForegroundColor = "White"}
	}
	New-EventLog -LogName MDT-ZeroTouch -Source MDT-ZeroTouch 2>1
	Write-EventLog -LogName MDT-ZeroTouch -EntryType $LogLevel -EventId $EventID -Source $Source -Message $Description
	Write-Host -ForegroundColor $ForegroundColor $LogLevel ":" $Description
	
	}

# //----------------------------------------------------------------------------
# //  Main Routine
# //----------------------------------------------------------------------------
	# // Get the pending devices from WDS
	[hashtable]$PendingDevices = ZTI\Get-PendingDevices
	# // Calculate how many loops to make
	[int]$TotalPending = $PendingDevices.Count / 3
	# // Initialize the loop
	$i = 0;Do { # // Start of Loop
		# // Iterate loop number
		$i++
		# // Process data
		[hashtable]$PendingDevicesData = ZTI\Process-PendingDevicesData -PendingDevices $PendingDevices -i $i
		[string]$MACAddress = $PendingDevicesData.MACAddress
		[string]$RequestID = $PendingDevicesData.RequestID
		[string]$UUID = $PendingDevicesData.UUID
		Write-Host $UUID
		
		# // Check if Computer MAC address is found in MDT database
		$SQLCommand = "SELECT ID FROM dbo.ComputerIdentity WHERE MACAddress = '$MACAddress'"
		$SQLDataset = SQL\Invoke-Command -Database $Database -DataSource $DataSource -SQLCommand $SQLCommand
		
		$ID = $SQLDataSet.Tables | Select-Object -ExpandProperty Rows
		
		# // If computer is found in MDT database proceed
		If ($ID) {
			ZTI\Write-Log -LogLevel "Information" -Description "Computer entry found for $MACAddress, checking if device is allowed to netboot" -EventID 4008 -Source $MACAdress
			$ComputerID = $ID.Get_Item(0)
			$SQLCommand = "SELECT netBoot FROM dbo.Settings WHERE Type = 'C' AND ID = '$ComputerID'"
			$SQLDataset = SQL\Invoke-Command -Database $Database -DataSource $DataSource -SQLCommand $SQLCommand
			$netBoot = $SQLDataset.Tables | Select-Object -ExpandProperty Rows
			$netBoot = $netBoot.Get_Item(0)
			# // If the computer is allowed to netboot proceed
			If ($netBoot -ne "FALSE") {
				ZTI\Write-Log -LogLevel "Information" -Description "Computer is allowed to netboot, approving device" -EventID 4009 -Source $MACAddress
				wdsutil.exe /Approve-AutoAddDevices /RequestID:$RequestID
			# // Reset computer information in both WDS and MDT database so on next boot computer will be rejected
				Sleep -Seconds 10
				wdsutil.exe /Delete-AutoAddDevices /DeviceType:ApprovedDevices
				$SQLCommand = "UPDATE dbo.Settings SET netBoot = 'FALSE' WHERE Type = 'C' AND ID = '$ComputerID'"
				$SQLDataset = SQL\Invoke-Command -Database $Database -DataSource $DataSource -SQLCommand $SQLCommand
				$RemoveComputer = AD\Remove-netBootComputerAccount -UUID $UUID
			
			# // If computer is not allowed to netboot, reject the device and clear the WDS database
			} Else {
				ZTI\Write-Log -LogLevel "Information" -Description "Computer is not allowed to netboot, rejecting device" -EventID 4010 -Source $MACAddress
				wdsutil.exe /Reject-AutoAddDevices /RequestID:$RequestID
				Sleep -Seconds 10
				wdsutil.exe /Delete-AutoAddDevices /DeviceType:RejectedDevices
				}
		# // If computer is not found in MDT Database, reject the device and clear the WDS database
		} Else {
			ZTI\Write-Log -LogLevel "Information" -Description "No computer entries found for $MACAddress, rejecting device" -EventID 4011 -Source $MACAddress
			wdsutil.exe /Reject-AutoAddDevices /RequestID:$RequestID
			Sleep -Seconds 10
			wdsutil.exe /Delete-AutoAddDevices /DeviceType:RejectedDevices
			}

		

	# // End of loop
	} until ($i -ge $TotalPending)