AppVeyorBYOC-Common.ps1

function PrintSummary($buildTarget, $AppVeyorUrl, $buildCloudId, $build_cloud_name, $imageName) {
    Write-host "`nNext steps:"  -ForegroundColor Cyan
    Write-host " - Optionally review build environment $build_cloud_name at $AppVeyorUrl/build-clouds/$buildCloudId" -ForegroundColor DarkGray
    Write-host " - To start building on $buildTarget select " -ForegroundColor DarkGray -NoNewline
    Write-host "$imageName " -NoNewline
    Write-host "build worker image " -ForegroundColor DarkGray -NoNewline 
    Write-host "and " -ForegroundColor DarkGray -NoNewline 
    Write-host "$build_cloud_name " -NoNewline
    Write-host "build cloud on AppVeyor project settings or in " -NoNewline -ForegroundColor DarkGray
    Write-host "appveyor.yml" -NoNewline
    Write-host ":"
    Write-host "`nbuild_cloud: $build_cloud_name" -ForegroundColor Gray
    Write-host "image: $imageName" -ForegroundColor Gray
    Write-Host "`n"
}
function CreateSlug($str) {
    return (($str.ToLower() -replace "[^a-z0-9-]", "-") -replace "-+", "-")
}

function CreateTempFolder {
    New-TemporaryFile | % {
        $parentFolder = Join-Path $(Split-Path $_ -Parent) "AppVeyorBYOC"
        if (-not (Test-Path $parentFolder)){
            mkdir $parentFolder
            if ($isMacOS -or $isLinux) {
                chmod 700 $parentFolder
            }
        }
        $tmpFolder = Join-Path $parentFolder $(Split-Path $_ -Leaf)
        rm $_ 
        mkdir $tmpFolder | out-null
        if ($isMacOS -or $isLinux) {
            chmod 700 $tmpFolder
        }
        (Resolve-Path $tmpFolder).Path
    }
}

function EnsureElevatedModeOnWindows() {
    if (-not $isLinux -and -not $isMacOS -and -not ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] 'Administrator')) {
        throw "This command should be run in elevated mode to install AppVeyor Host Agent. Run PowerShell in elevated mode (Run as Administrator) and re-run the command."
    }
}

function GetHomeDir {
    if ($isMacOS -or $isLinux) {
        return $env:HOME
    } else {
        return $env:USERPROFILE
    }
}

function InstallAppVeyorHostAgent($appVeyorUrl, $hostAuthorizationToken) {

    $APPVEYOR_HOST_AGENT_MSI_URL = "https://www.appveyor.com/downloads/appveyor/appveyor-host-agent.msi"
    $APPVEYOR_HOST_AGENT_DEB_URL = "https://www.appveyor.com/downloads/appveyor/appveyor-host-agent.deb"    

    Write-Host "`nInstalling AppVeyor Host Agent" -ForegroundColor Cyan

    if ($isLinux) {

        # Linux
        # =======

        Write-Host "OS: Linux" -ForegroundColor Gray

        if (-not (Test-Path '/opt/appveyor/host-agent')) {

            $debPath = "/tmp/appveyor-host-agent.deb"

            Write-Host "Downloading appveyor-host-agent.deb..." -ForegroundColor Gray
            (New-Object Net.WebClient).DownloadFile($APPVEYOR_HOST_AGENT_DEB_URL, $debPath)

            Write-Host "Installing Host Agent..." -ForegroundColor Gray
            sudo bash -c "APPVEYOR_URL=$appVeyorUrl HOST_AUTH_TOKEN=$hostAuthorizationToken dpkg -i $debPath"

            Remove-Item $debPath

            $hostAgentPid = (pidof appveyor-host-agent)
            if ($hostAgentPid) {
                Write-Host "Host Agent has been installed"
            } else {
                Write-Host "Something went wrong and Host Agent was not installed" -ForegroundColor Red
                throw "Error installing Host Agent"
            }

        } else {
            Write-Host "Host Agent is already installed" -ForegroundColor DarkGray
            /opt/appveyor/host-agent/appveyor version
        }

    } elseif ($isMacOS) {

        # macOS
        # =======

        Write-Host "OS: macOS" -ForegroundColor Gray

        $hostAgentProcess = Get-Process "appveyor-host-a" -ErrorAction SilentlyContinue
        if (-not $hostAgentProcess) {
            # make sure Homebrew is installed and available in the path
            if (-not (Get-Command brew -ErrorAction Ignore)) {
                Write-Warning "This command depends on Homebrew package manager. Please install it from https://brew.sh and re-run the command."
                return
            }

            $backupErrorActionPreference = $ErrorActionPreference
            $ErrorActionPreference = "Ignore"
            $brew_output = $(brew list appveyor-host-agent)
            $ErrorActionPreference = $backupErrorActionPreference
            if (-not $brew_output) {
                Write-Host "Installing Host Agent..." -ForegroundColor Gray
                bash -c "HOMEBREW_APPVEYOR_URL=$appVeyorUrl HOMEBREW_HOST_AUTH_TKN=$hostAuthorizationToken brew install appveyor/brew/appveyor-host-agent"
            } else{
                Write-Host "Host Agent already installed:" -ForegroundColor Gray
                brew list --versions appveyor-host-agent
            }

            Write-Host "Starting up Host Agent service..."
            brew services restart appveyor-host-agent

            $hostAgentProcess = Get-Process "appveyor-host-a" -ErrorAction SilentlyContinue
            if ($hostAgentProcess) {
                Write-Host "Host Agent has been installed"
            } else {
                Write-Host "Something went wrong and Host Agent was not installed" -ForegroundColor Red
                throw "Error installing Host Agent"
            }    
        } else {
            Write-Host "Host Agent is already installed" -ForegroundColor DarkGray
            brew list --versions appveyor-host-agent
        }

    } else {

        # Windows
        # =======

        Write-Host "OS: Windows" -ForegroundColor Gray

        $hostAgentService = Get-Service "Appveyor.HostAgent" -ErrorAction SilentlyContinue
        if (-not $hostAgentService) {

            Write-Host "Downloading appveyor-host-agent.msi..." -ForegroundColor Gray
            $msiPath = "$env:temp\appveyor-host-agent.msi"
            (New-Object Net.WebClient).DownloadFile($APPVEYOR_HOST_AGENT_MSI_URL, $msiPath)

            Write-Host "Installing Host Agent..." -ForegroundColor Gray
            cmd /c msiexec /i $msiPath /quiet APPVEYOR_URL="$appVeyorUrl" HOST_AUTHORIZATION_TOKEN="$hostAuthorizationToken"

            Remove-Item $msiPath
            $hostAgentService = Get-Service "Appveyor.HostAgent" -ErrorAction SilentlyContinue
            if ($hostAgentService) {
                Write-Host "Host Agent has been installed"
            } else {
                Write-Host "Something went wrong and Host Agent was not installed" -ForegroundColor Red
                throw "Error installing Host Agent"
            }                
        } else {
            Write-Host "Host Agent is already installed" -ForegroundColor DarkGray
        }
    }
}

function ValidateAppVeyorApiAccess($appVeyorUrl, $apiToken){
    Write-host "`nChecking AppVeyor API access..."  -ForegroundColor Cyan
    if ($apiToken -like "v2.*") {
        Write-Warning "Please select the API Key for specific account (not 'All Accounts') at '$appVeyorUrl/api-keys'"
        ExitScript
    }

    try {
        $response = Invoke-WebRequest -Uri $appVeyorUrl -UseBasicParsing -ErrorAction SilentlyContinue
        if ($response.StatusCode -ne 200) {
            Write-warning "AppVeyor URL '$appVeyorUrl' responded with code $($response.StatusCode)"
            ExitScript
        }
    }
    catch {
        Write-warning "Unable to connect to AppVeyor URL '$appVeyorUrl'. Error: $($error[0].Exception.Message)"
        ExitScript
    }

    $headers = @{
      "Authorization" = "Bearer $apiToken"
      "Content-type" = "application/json"
    }
    try {
        Invoke-RestMethod -Uri "$appVeyorUrl/api/projects" -Headers $headers -Method Get | Out-Null
    }
    catch {
        Write-warning "Unable to call AppVeyor REST API, please verify 'ApiToken' and ensure '-AppVeyorUrl' parameter is set if you are using on-premise AppVeyor Server."
        ExitScript
    }

    if ($appVeyorUrl -eq "https://ci.appveyor.com") {
          try {
            Invoke-RestMethod -Uri "$appVeyorUrl/api/build-clouds" -Headers $headers -Method Get | Out-Null
        }
        catch {
            Write-warning "Please contact support@appveyor.com and request enabling of 'BYOC' feature."
            ExitScript
        }
    }
    return $headers
}

function ValidateDependencies ($cloudType) {
    if ($cloudType -eq "Azure") {
        Write-host "`nChecking if Az PowerShell Module is installed..."  -ForegroundColor Cyan
        if (-not (Get-Module -Name *Az.* -ListAvailable)) {
            Write-Warning "Az PowerShell Module is not installed."
            $installAzPs = Read-Host "Enter 1 to install it or any other key to stop command execution and install it manually"
            if ($installAzPs -eq 1) {
                Install-Module -Name Az -Scope CurrentUser -AllowClobber
            }
            else {
                Write-Warning "Please install Az PowerShell Module with 'Install-Module -Name Az -Scope CurrentUser -AllowClobber' and re-run the command."
                ExitScript
            }
        }
    }

    if ($cloudType -eq "GCE") {
        Write-host "`nChecking if Google Cloud SDK is installed..."  -ForegroundColor Cyan
        if (-not (Get-Command gcloud -ErrorAction Ignore)) {
            Write-Warning "This command depends on Google Cloud SDK. Use 'choco install gcloudsdk' on Windows, for Linux follow https://cloud.google.com/sdk/docs/quickstart-linux, for Mac: https://cloud.google.com/sdk/docs/quickstart-macos"
            ExitScript
        }

        #TODO remove if GoogleCloud does not appear to be needed (if al canbe done with gcloud)
        if (-not (Get-Module -Name GoogleCloud -ListAvailable)) {
            Write-Warning "This command depends on Google Cloud PowerShell module. Please install them with the following command: 'Install-Module -Name GoogleCloud -Force; Import-Module -Name GoogleCloud"
            ExitScript
        }
        #Import module anyway, to be sure.
        Import-Module -Name GoogleCloud
    }

    if ($cloudType -eq "AWS") {
        Write-host "`nChecking if AWS Tools for PowerShell are installed..."  -ForegroundColor Cyan
        if (-not (Get-Module -Name *AWSPowerShell* -ListAvailable)) {
            Write-Warning "This command depends on AWS Tools for PowerShell. Please install them with the following command: 'Install-Module -Name AWSPowerShell -Force; Import-Module -Name AWSPowerShell'"
            ExitScript
        }
        if (-not (Get-Command Get-AWSCredentials -ErrorAction Ignore)) {
            Write-Warning "Unable to get 'Get-AWSCredentials' command. Please ensure latest 'AWSPowerShell' module is installed and imported"
            ExitScript
        }
    }
    
   if ($cloudType -eq "HyperV") {
        Write-host "`nChecking if Hyper-V tools are installed..."  -ForegroundColor Cyan
        Import-Module Hyper-V -ErrorAction Ignore
        if (-not (Get-Module Hyper-V -ErrorAction Ignore)) {
            Write-Warning "Hyper-V feature or its management tools are not installed. Please install Hyper-V feature with 'Install-WindowsFeature -Name Hyper-V -IncludeManagementTools' (for Windows Server) or 'Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All' (for Windows 10), restart computer if needed, and re-run the command."
            ExitScript
        }
    }
}

function GetPackerPath ([switch]$prerelease) {
    $packerVersion = if ($prerelease) {"1.8.7"} else {"1.4.3"}
    Write-host "`nChecking if Hashicorp Packer version $packerVersion is installed..."  -ForegroundColor Cyan
    if ((Get-Command packer -ErrorAction Ignore) -and (packer --version) -eq $packerVersion) {
        Write-Host "Packer version $packerVersion found" -ForegroundColor DarkGray
        return "packer"
    }
    else {
        $packerFolder = CreateTempFolder
        $zipPath = Join-Path $packerFolder "packer_$($packerVersion)_amd64.zip"
        Write-Host "Downloading Packer version $packerVersion to temporary folder..." -ForegroundColor DarkGray
        $currentSecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol
        $zipFile = if ($isLinux) {"packer_$($packerVersion)_linux_amd64.zip"} elseif ($isMacOS) {"packer_$($packerVersion)_darwin_amd64.zip"} else {"packer_$($packerVersion)_windows_amd64.zip"} 
        [System.Net.ServicePointManager]::SecurityProtocol = "Tls12"
        $URL = if ($prerelease) {"https://appveyordownloads.blob.core.windows.net/packer/packer-1.4.x-win-nightly.zip"} else {"https://releases.hashicorp.com/packer/$packerVersion/$zipFile"}
        (New-Object Net.WebClient).DownloadFile($URL, $zipPath)
        [System.Net.ServicePointManager]::SecurityProtocol = $currentSecurityProtocol
        Expand-Archive -LiteralPath $zipPath -DestinationPath $packerFolder
        Remove-Item $zipPath -force -ErrorAction Ignore
        $packerPath = Join-Path $packerFolder "packer"
        if ($isMacOS -or $isLinux) {
            chmod 700 $packerPath
        }
        Write-Host "Using $packerPath" -ForegroundColor DarkGray
        return $packerPath
    }
}

function ParseImageFeaturesAndCustomScripts ($imageFeatures, $imageTemplate, $ImageCustomScript, $ImageCustomScriptAfterReboot, $imageOs) {
    $imageFeatures = $imageFeatures.Trim()
    if(($imageFeatures.Contains(' ') -and -not $imageFeatures.Contains(',')) -or $imageFeatures.Contains(';')) {
        Write-Warning "'ImageFeatures' should be comma-separate list or single value"
        ExitScript
    }

    $packer_file = Get-Content $imageTemplate | ConvertFrom-Json

    if ($imageFeatures -and $imageOs -eq "Windows") {
        $imageFeatures = ($imageFeatures.Split(',') | % { $_.Trim() })

        $before_reboot_script = @()
        $imageFeatures | % {
            $scriptName1 = "install_$_.ps1"
            $scriptName2 = "$_.ps1"
            if (Test-Path "$PSScriptRoot/scripts/Windows/$scriptName1") {
                $before_reboot_script += "{{ template_dir }}/scripts/Windows/$scriptName1"
                }
            elseif (Test-Path "$PSScriptRoot/scripts/Windows/$scriptName2") {
                $before_reboot_script += "{{ template_dir }}/scripts/Windows/$scriptName2"
                }
            else {
                Write-Warning "Unable to find $scriptName1 or $scriptName2 in $PSScriptRoot/scripts/Windows"
                ExitScript
            }
        }

        $after_reboot_scripts = @()
        $imageFeatures | % {
            $scriptName1 = "install_$($_)_after_reboot.ps1"
            $scriptName2 = "$($_)_after_reboot.ps1"
			$scriptName3 = "install_$($_)_after_restart.ps1"
            if (Test-Path "$PSScriptRoot/scripts/Windows/$scriptName1") {
                $after_reboot_scripts += "{{ template_dir }}/scripts/Windows/$scriptName1"
                }
            elseif (Test-Path "$PSScriptRoot/scripts/Windows/$scriptName2") {
                $after_reboot_scripts += "{{ template_dir }}/scripts/Windows/$scriptName2"
                }
			elseif (Test-Path "$PSScriptRoot/scripts/Windows/$scriptName3") {
				$after_reboot_scripts += "{{ template_dir }}/scripts/Windows/$scriptName3"
				}
        }

        $before_reboot = @{
            'type' = 'powershell'
            'scripts' = $before_reboot_script
            'elevated_user' = '{{user `install_user`}}'
            'elevated_password' = '{{user `install_password`}}'
        }
        $packer_file.provisioners += $before_reboot

        if ($after_reboot_scripts.Count -gt 0) {
            $reboot = @{
                'type' = 'windows-restart'
                'restart_timeout' = '30m'
            }
            $packer_file.provisioners += $reboot

            $after_reboot = @{
                'type' = 'powershell'
                'scripts' = $after_reboot_scripts
                'elevated_user' = '{{user `install_user`}}'
                'elevated_password' = '{{user `install_password`}}'
            }
            $packer_file.provisioners +=$after_reboot
        }
		
		$disableWindowsFeatures = @{
			'type' = 'powershell'
            'scripts' = @("{{ template_dir }}/scripts/Windows/disable_windows_background_services.ps1")
			'only' = @('hyperv-iso')
            'elevated_user' = '{{user `install_user`}}'
            'elevated_password' = '{{user `install_password`}}'
		}
		
		$packer_file.provisioners += $disableWindowsFeatures
		

    }

    if($ImageCustomScript) {
        $fileExtension =  if ($imageOs -eq "Windows") {"ps1"} elseif ($imageOs -eq "Linux") {"sh"}
        $provisionerShell =  if ($imageOs -eq "Windows") {"powershell"} elseif ($imageOs -eq "Linux") {"shell"}
        $ImageCustomScript = [System.Text.Encoding]::UTF8.GetString([System.Convert]::FromBase64String($ImageCustomScript))
        $customScriptFile = Join-Path $(CreateTempFolder) "$(New-Guid).$fileExtension"
        $ImageCustomScript | Set-Content -Path $customScriptFile
        $custom_before_reboot_script =  @($customScriptFile)

        $custom_before_reboot = 
        if ($imageOs -eq "Windows") {
            @{
            'type' = $provisionerShell
            'scripts' = $custom_before_reboot_script
            'elevated_user' = '{{user `install_user`}}'
            'elevated_password' = '{{user `install_password`}}'
            }
        }
        elseif ($imageOs -eq "Linux") {
            @{
            'type' = $provisionerShell
            'scripts' = $custom_before_reboot_script
            }
        }

       $packer_file.provisioners += $custom_before_reboot
    }

    if($ImageCustomScriptAfterReboot -and $imageOs -eq "Windows") {
        $reboot = @{
            'type' = 'windows-restart'
            'restart_timeout' = '30m'
        }
        $packer_file.provisioners += $reboot

        $ImageCustomScriptAfterReboot = [System.Text.Encoding]::UTF8.GetString([System.Convert]::FromBase64String($ImageCustomScriptAfterReboot))
        $customScriptFileAfterReboot = Join-Path $(CreateTempFolder) "$(New-Guid).ps1"
        $ImageCustomScriptAfterReboot | Set-Content -Path $customScriptFileAfterReboot
        $custom_after_reboot_scripts = @($customScriptFileAfterReboot)
        $custom_after_reboot = @{
            'type' = 'powershell'
            'scripts' = $custom_after_reboot_scripts
            'elevated_user' = '{{user `install_user`}}'
            'elevated_password' = '{{user `install_password`}}'
        }
        $packer_file.provisioners += $custom_after_reboot
    }

    $imageTemplateCustom = Join-Path $(CreateTempFolder) $(Split-Path $ImageTemplate -Leaf)
    Copy-Item -Path "$PSScriptRoot\scripts" -Destination $(Split-Path $imageTemplateCustom -Parent) -recurse -Force
    Copy-Item -Path "$PSScriptRoot\hyper-v" -Destination $(Split-Path $imageTemplateCustom -Parent) -recurse -Force
    Copy-Item -Path "$PSScriptRoot\http" -Destination $(Split-Path $imageTemplateCustom -Parent) -recurse -Force
    $packer_file | ConvertTo-Json -Depth 20 | Set-Content -Path $imageTemplateCustom
	
    return $imageTemplateCustom
}

function SetBuildWorkerImage ($headers, $ImageName, $ImageOs) {
    Write-host "`nEnsure build worker image is available for AppVeyor projects" -ForegroundColor Cyan
    $images = Invoke-RestMethod -Uri "$AppVeyorUrl/api/build-worker-images" -Headers $headers -Method Get
    $image = $images | Where-Object ({$_.name -eq $ImageName})[0]
    if (-not $image) {
        $body = @{
            name = $imageName
            osType = $ImageOs
        }

        $jsonBody = $body | ConvertTo-Json
        Invoke-RestMethod -Uri "$AppVeyorUrl/api/build-worker-images" -Headers $headers -Body $jsonBody -Method Post | Out-Null
        Write-host "AppVeyor build worker image '$ImageName' has been created." -ForegroundColor DarkGray
    } else {
        Write-host "AppVeyor build worker image '$ImageName' already exists." -ForegroundColor DarkGray
    }
}

function CreatePassword {
    $upper = (65..90) | Get-Random | % {[char]$_}
    $lower = (97..122) | Get-Random | % {[char]$_}
    $symbol = @('!', '@', '#', '$', '%', '^', '*', '(', ')', '_', '+', '=')[(Get-Random -Maximum 12)]
    $base = (New-Guid).ToString().SubString(0, 17).Replace("-", "").ToCharArray()
    $bound1 = [int]($base.Length/3)
    $bound2 = [int]($base.Length/3)*2
    $bound3 = $base.Length - 1
    $base[(Get-Random -Minimum 0 -Maximum $bound1)] = $upper
    $base[(Get-Random -Minimum $bound1 -Maximum $bound2)] = $lower
    $base[(Get-Random -Minimum $bound2 -Maximum $bound3)] = $symbol
    return -join $base
}

function GetOrCreateServicePrincipal ($service_principal_name, $build_cloud_name, $headers) {
    $sp = Get-AzADServicePrincipal -DisplayName $service_principal_name
    $app = Get-AzADApplication -DisplayName $service_principal_name
    if (-not $sp -and $app) {
        Write-Warning "`nService principal '$($service_principal_name)' does not exist, but Azure AD application with the same name already exists." 
        "`nPlease either delete that Azure Ad Application or use another service principal name."
        ExitScript
    }
    if (-not $sp) {
        $sp = New-AzADServicePrincipal -DisplayName $service_principal_name -Role Contributor
        $sp_cred = $sp | New-AzADSpCredential -StartDate (Get-Date) -EndDate (Get-Date).AddYears(10)
        $azure_client_secret = $sp_cred.SecretText
        $azure_client_id = $sp.AppId
    }
    else {
        $clouds = Invoke-RestMethod -Uri "$($AppVeyorUrl)/api/build-clouds" -Headers $headers -Method Get
        $cloud = $clouds | ? ({$_.name -eq $build_cloud_name})[0]
        if ($cloud) {
            $settings = Invoke-RestMethod -Uri "$($AppVeyorUrl)/api/build-clouds/$($cloud.buildCloudId)" -Headers $headers -Method Get
            $azure_client_id = $settings.settings.cloudSettings.azureAccount.clientId
            $azure_client_secret = $settings.settings.cloudSettings.azureAccount.clientSecret
            $service_principal_name = (Get-AzADServicePrincipal -ApplicationId $azure_client_id).DisplayName
        }
        else {
            $new_service_principal_name = "$service_principal_name-$((New-Guid).ToString().SubString(0, 8))"
            Write-Warning "Azure AD service principal and application with the name '$service_principal_name' already exist, creating '$new_service_principal_name'."
            Write-Warning "Consider deleting '$service_principal_name' service principal and application if they are not being used with any other service."
            GetOrCreateServicePrincipal $new_service_principal_name
            return
        }
    }
    Write-host "Using Azure AD service principal '$($service_principal_name)'" -ForegroundColor DarkGray
    return @{
        "azure_client_id" = $azure_client_id
        "azure_client_secret" = $azure_client_secret
    }
}

function GetImageTemplatePath ($imageTemplate) {
    if ($imageTemplate) {
        if (Test-Path "$PSScriptRoot/$ImageTemplate") {
            return "$PSScriptRoot/$ImageTemplate"
        }
        elseif (Test-Path "$ImageTemplate") {
            return $ImageTemplate
        }
        Write-Warning "`nUnable to find Packer image template '$ImageTemplate'."
        ExitScript
    }
    elseif ($ImageOs -eq "Windows") {
        return "$PSScriptRoot/minimal-windows-server.json"
    }
    elseif ($ImageOs -eq "Linux") {
        return "$PSScriptRoot/minimal-ubuntu.json"
    }
}

# FROM https://github.com/TheDotSource/New-ISOFile
function New-ISOFile {
    <#
    .SYNOPSIS
        Create an ISO file from a source folder.

    .DESCRIPTION
        Create an ISO file from a source folder.
        Optionally speicify a boot image and media type.

        Based on original function by Chris Wu.
        https://gallery.technet.microsoft.com/scriptcenter/New-ISOFile-function-a8deeffd (link appears to be no longer valid.)

        Changes:
            - Updated to work with PowerShell 7
            - Added a bit more error handling and verbose output.
            - Features removed to simplify code:
                * Clipboard support.
                * Pipeline input.

    .PARAMETER source
        The source folder to add to the ISO.

    .PARAMETER destinationIso
        The ISO file to create.

    .PARAMETER bootFile
        Optional. Boot file to add to the ISO.

    .PARAMETER media
        Optional. The media type of the resulting ISO (BDR, CDR etc). Defaults to DVDPLUSRW_DUALLAYER.

    .PARAMETER title
        Optional. Title of the ISO file. Defaults to "untitled".

    .PARAMETER force
        Optional. Force overwrite of an existing ISO file.

    .INPUTS
        None.

    .OUTPUTS
        None.

    .EXAMPLE
        New-ISOFile -source c:\forIso\ -destinationIso C:\ISOs\testiso.iso

        Simple example. Create testiso.iso with the contents from c:\forIso

    .EXAMPLE
        New-ISOFile -source f:\ -destinationIso C:\ISOs\windowsServer2019Custom.iso -bootFile F:\efi\microsoft\boot\efisys.bin -title "Windows2019"

        Example building Windows media. Add the contents of f:\ to windowsServer2019Custom.iso. Use efisys.bin to make the disc bootable.

    .LINK

    .NOTES
        01           Alistair McNair          Initial version.

    #>
    [CmdletBinding(SupportsShouldProcess=$true,ConfirmImpact="Low")]
    Param
    (
        [parameter(Mandatory=$true,ValueFromPipeline=$false)]
        [string]$source,
        [parameter(Mandatory=$true,ValueFromPipeline=$false)]
        [string]$destinationIso,
        [parameter(Mandatory=$false,ValueFromPipeline=$false)]
        [string]$bootFile = $null,
        [Parameter(Mandatory=$false,ValueFromPipeline=$false)]
        [ValidateSet("CDR","CDRW","DVDRAM","DVDPLUSR","DVDPLUSRW","DVDPLUSR_DUALLAYER","DVDDASHR","DVDDASHRW","DVDDASHR_DUALLAYER","DISK","DVDPLUSRW_DUALLAYER","BDR","BDRE")]
        [string]$media = "DVDPLUSRW_DUALLAYER",
        [Parameter(Mandatory=$false,ValueFromPipeline=$false)]
        [string]$title = "untitled",
        [Parameter(Mandatory=$false,ValueFromPipeline=$false)]
        [switch]$force
      )

    begin {

        Write-Verbose ("Function start.")

    } # begin

    process {

        Write-Verbose ("Processing nested system " + $vmName)

        ## Set type definition
        Write-Verbose ("Adding ISOFile type.")

        $typeDefinition = @'
        public class ISOFile  {
            public unsafe static void Create(string Path, object Stream, int BlockSize, int TotalBlocks) {
                int bytes = 0;
                byte[] buf = new byte[BlockSize];
                var ptr = (System.IntPtr)(&bytes);
                var o = System.IO.File.OpenWrite(Path);
                var i = Stream as System.Runtime.InteropServices.ComTypes.IStream;

                if (o != null) {
                    while (TotalBlocks-- > 0) {
                        i.Read(buf, BlockSize, ptr); o.Write(buf, 0, bytes);
                    }

                    o.Flush(); o.Close();
                }
            }
        }
'@

        ## Create type ISOFile, if not already created. Different actions depending on PowerShell version
        if (!('ISOFile' -as [type])) {

            ## Add-Type works a little differently depending on PowerShell version.
            ## https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/add-type
            switch ($PSVersionTable.PSVersion.Major) {

                ## 7 and (hopefully) later versions
                {$_ -ge 7} {
                    Write-Verbose ("Adding type for PowerShell 7 or later.")
                    Add-Type -CompilerOptions "/unsafe" -TypeDefinition $typeDefinition
                } # PowerShell 7

                ## 5, and only 5. We aren't interested in previous versions.
                5 {
                    Write-Verbose ("Adding type for PowerShell 5.")
                    $compOpts = New-Object System.CodeDom.Compiler.CompilerParameters
                    $compOpts.CompilerOptions = "/unsafe"

                    Add-Type -CompilerParameters $compOpts -TypeDefinition $typeDefinition
                } # PowerShell 5

                default {
                    ## If it's not 7 or later, and it's not 5, then we aren't doing it.
                    throw ("Unsupported PowerShell version.")

                } # default

            } # switch

        } # if


        ## Add boot file to image
        if ($bootFile) {

            Write-Verbose ("Optional boot file " + $bootFile + " has been specified.")

            ## Display warning if Blu Ray media is used with a boot file.
            ## Not sure why this doesn't work.
            if(@('BDR','BDRE') -contains $media) {
                    Write-Warning ("Selected boot image may not work with BDR/BDRE media types.")
            } # if

            if (!(Test-Path -Path $bootFile)) {
                throw ($bootFile + " is not valid.")
            } # if

            ## Set stream type to binary and load in boot file
            Write-Verbose ("Loading boot file.")

            try {
                $stream = New-Object -ComObject ADODB.Stream -Property @{Type=1} -ErrorAction Stop
                $stream.Open()
                $stream.LoadFromFile((Get-Item -LiteralPath $bootFile).Fullname)

                Write-Verbose ("Boot file loaded.")
            } # try
            catch {
                throw ("Failed to open boot file. " + $_.exception.message)
            } # catch


            ## Apply the boot image
            Write-Verbose ("Applying boot image.")

            try {
                $boot = New-Object -ComObject IMAPI2FS.BootOptions -ErrorAction Stop
                $boot.AssignBootImage($stream)

                Write-Verbose ("Boot image applied.")
            } # try
            catch {
                throw ("Failed to apply boot file. " + $_.exception.message)
            } # catch


            Write-Verbose ("Boot file applied.")

        }  # if

        ## Build array of media types
        $mediaType = @(
            "UNKNOWN",
            "CDROM",
            "CDR",
            "CDRW",
            "DVDROM",
            "DVDRAM",
            "DVDPLUSR",
            "DVDPLUSRW",
            "DVDPLUSR_DUALLAYER",
            "DVDDASHR",
            "DVDDASHRW",
            "DVDDASHR_DUALLAYER",
            "DISK",
            "DVDPLUSRW_DUALLAYER",
            "HDDVDROM",
            "HDDVDR",
            "HDDVDRAM",
            "BDROM",
            "BDR",
            "BDRE"
        )

        Write-Verbose ("Selected media type is " + $media + " with value " + $mediaType.IndexOf($media))

        ## Initialise image
        Write-Verbose ("Initialising image object.")
        try {
            $image = New-Object -ComObject IMAPI2FS.MsftFileSystemImage -Property @{VolumeName=$title} -ErrorAction Stop
            $image.ChooseImageDefaultsForMediaType($mediaType.IndexOf($media))

            Write-Verbose ("initialised.")
        } # try
        catch {
            throw ("Failed to initialise image. " + $_.exception.Message)
        } # catch


        ## Create target ISO, throw if file exists and -force parameter is not used.
        if ($PSCmdlet.ShouldProcess($destinationIso)) {

            if (!($targetFile = New-Item -Path $destinationIso -ItemType File -Force:$Force -ErrorAction SilentlyContinue)) {
                throw ("Cannot create file " + $destinationIso + ". Use -Force parameter to overwrite if the target file already exists.")
            } # if

        } # if


        ## Get source content from specified path
        Write-Verbose ("Fetching items from source directory.")
        try {
            $sourceItems = Get-ChildItem -LiteralPath $source -ErrorAction Stop
            Write-Verbose ("Got source items.")
        } # try
        catch {
            throw ("Failed to get source items. " + $_.exception.message)
        } # catch


        ## Add these to our image
        Write-Verbose ("Adding items to image.")

        foreach($sourceItem in $sourceItems) {

            try {
                $image.Root.AddTree($sourceItem.FullName, $true)
            } # try
            catch {
                throw ("Failed to add " + $sourceItem.fullname + ". " + $_.exception.message)
            } # catch

        } # foreach

        ## Add boot file, if specified
        if ($boot) {
            Write-Verbose ("Adding boot image.")
            $Image.BootImageOptions = $boot
        }

        ## Write out ISO file
        Write-Verbose ("Writing out ISO file to " + $targetFile)

        try {
            $result = $image.CreateResultImage()
            [ISOFile]::Create($targetFile.FullName,$result.ImageStream,$result.BlockSize,$result.TotalBlocks)
        } # try
        catch {
            throw ("Failed to write ISO file. " + $_.exception.Message)
        } # catch

        Write-Verbose ("File complete.")

        ## Return file details
        return $targetFile

    } # process

    end {
        Write-Verbose ("Function complete.")
    } # end

} # function

#from https://d-fens.ch/2013/11/01/nobrainer-using-powershell-to-convert-an-ipv4-subnet-mask-length-into-a-subnet-mask-address/
function Convert-IpAddressToMaskLength([string] $dottedIpAddressString)
{
  $result = 0; 
  # ensure we have a valid IP address
  [IPAddress] $ip = $dottedIpAddressString;
  $octets = $ip.IPAddressToString.Split('.');
  foreach($octet in $octets)
  {
    while(0 -ne $octet) 
    {
      $octet = ($octet -shl 1) -band [byte]::MaxValue
      $result++; 
    }
  }
  return $result;
}