#requires -Version 2.0 -Modules PowerShellGet -RunAsAdministrator

<#
        .SYNOPSIS
      Install some DSC Resources

        .DESCRIPTION
      Getting, install, or update DSC Resources I want to have.
      It could be used to install every Module from the Gallery.
      However, this is something I do with DSC afterwards!

        .EXAMPLE
      PS C:\> .\invoke-GetDSCResources.ps1

        .EXAMPLE
      PS C:\> .\invoke-GetDSCResources.ps1 -verbose
      VERBOSE: Populating RepositorySourceLocation property for module PSDscResources.
      VERBOSE: Try to update PSDscResources
      VERBOSE: Updated PSDscResources

        .NOTES
      Small script I created for myself.
      I have to prepare DSC systems from time to time, and I want to have the same set of DSC resources on all of them.
      Mainly because I'm lazy, but I'm an old-school Unix guy: Never type something more than two times: AUTOMATE.

      I install the resources system wide!
      That is why we have the Elevated Shell requirement (#Requires -RunAsAdministrator).
      If you want to use it just for the current user, change the Scope in $paramInstallModule from 'AllUsers' to 'CurrentUser'.

      TODO: Pester Test is missing
      DONE: Make it more robust

      Disclaimer: The code is provided 'as is,' with all possible faults, defects or errors, and without warranty of any kind.

      Author: Joerg Hochwald

      License: http://unlicense.org

        .LINK
      Author http://jhochwald.com

        .Link
      License http://unlicense.org
#>
[CmdletBinding()]
param ()

begin
{
	# Define some defaults
	$STP = 'Stop'
	$SC = 'SilentlyContinue'

	# Suppressing the PowerShell Progress Bar
	$script:ProgressPreference = $SC

	# Create a list of the DSC Resources I want
	$NewDSCModules = @(
		'PSDscResources',
		'xNetworking',
		'xPSDesiredStateConfiguration',
		'xWebAdministration',
		'xCertificate',
		'xComputerManagement',
		'xActiveDirectory',
		'SystemLocaleDsc',
		'xRemoteDesktopAdmin',
		'xPendingReboot',
		'xSmbShare',
		'xWindowsUpdate',
		'xDscDiagnostics',
		'xCredSSP',
		'xDnsServer',
		'xWinEventLog',
		'xDhcpServer',
		'xHyper-V',
		'xStorage',
		'xWebDeploy'
		'xRemoteDesktopSessionHost',
		'xDismFeature',
		'xSystemSecurity',
		'WebAdministrationDsc',
		'OfficeOnlineServerDsc',
		'AuditPolicyDsc',
		'xDFS',
		'SecurityPolicyDsc',
		'xReleaseManagement',
		'xExchange',
		'xDefender',
		'xWindowsEventForwarding',
		'cHyper-V'
	)
}

process
{
	foreach ($NewDSCModule in $NewDSCModules)
	{
		# Cleanup
		$ModuleIsAvailable = $null

		# Check: Do I have the resource?
		$paramGetModule = @{
			ListAvailable = $true
			Name			  = $NewDSCModule
			ErrorAction   = $SC
			WarningAction = $SC
		}
		$ModuleIsAvailable = (Get-Module @paramGetModule)

		if (-not ($ModuleIsAvailable))
		{
			# Nope: Install the resource
			try
			{
				Write-Verbose -Message "Try to install $NewDSCModule"

				$paramInstallModule = @{
					Name			  = $NewDSCModule
					Scope		     = AllUsers
					Force		     = $true
					ErrorAction   = $STP
					WarningAction = $SC
				}
				$null = (Install-Module @paramInstallModule)

				Write-Verbose -Message "Installed $NewDSCModule"
			}
			catch
			{
				# Whoopsie
				$paramWriteWarning = @{
					Message = "Sorry, unable to install $NewDSCModule"
					ErrorAction = $SC
				}
				Write-Warning @paramWriteWarning
			}
		}
		else
		{
			try
			{
				Write-Verbose -Message "Try to update $NewDSCModule"

				# TODO: Implement the check from invoke-ModuleUpdates.ps1 to prevent the unneeded update tries.
				$paramUpdateModule = @{
					Name			  = $NewDSCModule
					Confirm		  = $false
					ErrorAction   = $STP
					WarningAction = $SC
				}
				$null = (Update-Module @paramUpdateModule)

				Write-Verbose -Message "Updated $NewDSCModule"
			}
			catch
			{
				# Whoopsie
				$paramWriteWarning = @{
					Message = "Sorry, unable to update $NewDSCModule"
					ErrorAction = $SC
				}
				Write-Warning @paramWriteWarning
			}
		}
	}
}

end
{
	# No longer suppressing the PowerShell Progress Bar
	$script:ProgressPreference = 'Continue'
}