#############################################################################
#       Author: Cengiz Ulusahin
#       Version: 3.0
#       Date: 04/08/2020
#       Description: Enable HotAdd CPU and Memory on VMs
#
#############################################################################

#Function to generate wait time progress bar
function Start-Sleep($seconds) {
    $doneDT = (Get-Date).AddSeconds($seconds)
    while($doneDT -gt (Get-Date)) {
        $secondsLeft = $doneDT.Subtract((Get-Date)).TotalSeconds
        $percent = ($seconds - $secondsLeft) / $seconds * 100
        Write-Progress -Activity "Sleeping" -Status "Sleeping..." -SecondsRemaining $secondsLeft -PercentComplete $percent
        [System.Threading.Thread]::Sleep(500)
    }
    Write-Progress -Activity "Sleeping" -Status "Sleeping..." -SecondsRemaining 0 -Completed
}

#Function for Logging
Function Write-Log
{
Param ([string]$logstring)
$stamp = (Get-Date).toString("yyyy/MM/dd HH:mm:ss")
$line = "$stamp $logstring"
Add-content $logfile -value $line
}

#Function for Enabling Hot Add
function EnableHotAdd{
$VMConfig = Get-VM $VM.Name | Get-View
$VMConfig.ReconfigVM($vmConfigSpec)

        $HotAddStatus = Get-VM $VM.Name
        $HotAddCPUStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.CpuHotAddEnabled))
        $HotAddMEMStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.MemoryHotAddEnabled))
                
                If ($HotAddCPUStatus -eq $True -OR $HotAddMEMStatus -eq $True) {

                    write-log("[SUCCESS] HotAdd for $($VM.Name) was enabled")

                }else{

                    write-log("[FAIL] HotAdd for $($VM.Name) was not enabled")
                } 
}

#Function for Powering off VM
function PowerOffVM{
         #Shutdown Guest OS / Power off VM
         Get-VM $VM.Name | Shutdown-VMGuest -Confirm:$false

         #Wait for VM to power off before executing config cmd  
         while((Get-VM $VM.Name).PowerState -ne 'PoweredOff') {
         
         Start-Sleep -Seconds 10
         }
                 $HotAddStatus = Get-VM $VM.Name
                 $HotAddCPUStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.CpuHotAddEnabled))
                 $HotAddMEMStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.MemoryHotAddEnabled))

                         If ((Get-VM $VM.Name).PowerState -eq 'PoweredOff') {

                             write-log("[SUCCESS] $($VM.Name) was powered off")

                         }else{

                             write-log("[FAIL] $($VM.Name) was not powered off")
                         }
}

#Function for Powering on VM
function PowerOnVM{
Get-VM $VM.Name | Start-VM

                If ((Get-VM $VM.Name).PowerState -eq 'PoweredOn') {

                    write-log("[SUCCESS] $($VM.Name) was powered on")

                }else{

                    write-log("[FAIL] $($VM.Name) was not powered on")
                }
}

#Variables
$vcenter = Read-Host -Prompt 'Enter vCenter name'
$cred = Get-Credential
$CSVPath = Read-Host -Prompt 'Enter CSV Path'
$HotAddVMs = Import-CSV $CSVPath\vms.csv
$logfile = New-Item $CSVPath\hotadd-script-log.txt -Force
$vmConfigSpec = New-Object VMware.Vim.VirtualMachineConfigSpec
$vmConfigSpec.CpuHotAddEnabled = "True"
$vmConfigSpec.MemoryHotAddEnabled = "True"

Connect-VIServer $vcenter -Credential $cred

        Foreach ($VM in ($HotAddVMs)) {

            $VMTools = Get-VM $VM.Name
            $VMToolsStatus = $VMTools.ExtensionData.Guest.ToolsVersionStatus

            if ($VMToolsStatus -eq 'guestToolsNotInstalled') {

                write-log("[PASS] $($VM.Name) has no VMTools installed")

            }else{    

                $HotAddStatus = Get-VM $VM.Name
                $HotAddCPUStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.CpuHotAddEnabled))
                $HotAddMEMStatus = [System.Convert]::ToBoolean($($HotAddStatus.ExtensionData.Config.MemoryHotAddEnabled))

                If ($HotAddCPUStatus -eq $False -OR $HotAddMEMStatus -eq $False) {

                            If ((Get-VM $VM.Name).PowerState -eq 'PoweredOff') {

                                write-log("[PASS] $($VM.Name) was already powered off")

                                EnableHotAdd

                                write-log("[PASS] $($VM.Name) has been left powered off")

                            }else{

                                PowerOffVM
                                EnableHotAdd
                                PowerOnVM
                            }
                    }else{

                        write-log("[PASS] HotAdd for $($VM.Name) was already enabled")
                }
            }
        }