internal/functions/Resolve-DomainController.ps1

function Resolve-DomainController
{
    <#
    .SYNOPSIS
        Resolves a domain to a specific domaincontroller.
     
    .DESCRIPTION
        Resolves a domain to a specific domaincontroller.
     
    .PARAMETER Server
        The server / domain to work with.
     
    .PARAMETER Credential
        The credentials to use for this operation.
     
    .PARAMETER Type
        The type of DC to resolve to.
        Governed by the 'ADMF.DCSelectionMode' configuration setting.
     
    .PARAMETER Confirm
        If this switch is enabled, you will be prompted for confirmation before executing any operations that change state.
     
    .PARAMETER WhatIf
        If this switch is enabled, no actions are performed but informational messages will be displayed that explain what would happen if the command were to run.
     
    .EXAMPLE
        PS C:\> Resolve-DomainController @parameters
 
        Picks the server to work against.
    #>

    [Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSUseDeclaredVarsMoreThanAssignments", "")]
    [OutputType([string])]
    [CmdletBinding(SupportsShouldProcess = $true)]
    param (
        [PSFComputer]
        $Server,
        
        [PSCredential]
        $Credential,

        [ValidateSet('PDCEmulator', 'Random')]
        [string]
        $Type = (Get-PSFConfigValue -FullName 'ADMF.DCSelectionMode' -Fallback 'PDCEmulator')
    )
    
    begin
    {
        $parameters = $PSBoundParameters | ConvertTo-PSFHashtable -Include Server, Credential
        $parameters['Debug'] = $false
    }
    process
    {
        $targetString = $Server
        if (-not $targetString) { $targetString = $env:USERDNSNAME }
        $null = Invoke-PSFProtectedCommand -ActionString 'Resolve-DomainController.Connecting' -ActionStringValues $targetString -Target $targetString -ScriptBlock {
            $domainController = Get-ADDomainController @parameters -ErrorAction Stop
        } -PSCmdlet $PSCmdlet -EnableException $true -RetryCount 5 -RetryWait 2 -Confirm:$false -Tag ResolveDC
        
        if ($domainController.HostName -eq $Server) {
            Write-PSFMessage -Level Host -String 'Resolve-DomainController.Resolved' -StringValues $domainController.HostName
            return $domainController.HostName
        }
        if ($domainController.Name -eq $Server) {
            Write-PSFMessage -Level Host -String 'Resolve-DomainController.Resolved' -StringValues $domainController.Name
            return $domainController.Name
        }

        switch ($Type) {
            'Random' {
                Write-PSFMessage -Level Host -String 'Resolve-DomainController.Resolved' -StringValues $domainController.HostName
                return $domainController.HostName
            }
            default {
                $domain = Get-ADDomain @parameters
                Write-PSFMessage -Level Host -String 'Resolve-DomainController.Resolved' -StringValues $domain.PDCEmulator
                $domain.PDCEmulator
            }
        }
    }
}