Set-PowerPointLanguage

Set-PowerPointLanguage.ps1

<#
.SYNOPSIS
	Change language settings for a PowerPoint presentation

.EXAMPLE
PS> Set-PowerPointLanguage -Path MyPres.pptx

Writes a copy of  MyPres.pptx to  MyPres.en-us.pptx with the language set to 'en-US' - English (the default)
.EXAMPLE
PS> Set-PowerPointLanguage -Path MyPres.pptx  -Language de-DE

Sets the language to 'de-DE' (German)

.EXAMPLE
PS> gci -rec -inc *.pptx | Set-PowerPointLanguage -OutputPath {[io.path]::ChangeExtension($_.Fullname, ".en-us.pptx")} -whatif

Shows what will happen if you try to set the language to all pptx files in the current directory
#>
function Set-PowerPointLanguage {
	[Alias("sppl")]
	[CmdletBinding(SupportsShouldProcess)]
	param(
		[ValidatePattern("\.pptx$", ErrorMessage = "Eeh - this only work on PowerPoint files")]
		[Parameter(Mandatory, ValueFromPipelineByPropertyName)]
		[Alias("PSPath")]
		[string] $Path
		,
		[Parameter(ValueFromPipelineByPropertyName)]
		[string] $OutputPath
		,
		[ValidateSet("en-US", "de-DE", IgnoreCase = $false)] # since this are the official languages of PSConfEU
		[string] $Language = 'en-US'
		,
		[switch] $Force
	)
	process {
		$p = $null
		$paths = $pscmdlet.GetResolvedProviderPathFromPSPath($Path, [ref] $p)
		foreach ($resolvedPath in $Paths) {
			if (!$PSBoundParameters.OutputPath) {
				$OutputPath = [io.path]::ChangeExtension($resolvedPath, ".$Language.pptx")
			}
			$OutputPath = $pscmdlet.GetUnresolvedProviderPathFromPSPath($OutputPath)

			$relSource = Resolve-Path -Relative $resolvedPath
			$relOutput = $OutputPath
			if ($OutputPath -like "$pwd*") {
				$pwdLen = $pwd.ProviderPath.Length
				$relOutput = "." + $OutputPath.SubString($pwdlen, $outputPath.length - $pwdlen)
			}
			if ($Force -or $pscmdlet.ShouldProcess( "$relSource -> $relOutput", "Change Language to '$Language'")) {

				$resolvedItem = Get-Item $resolvedPath
				if ($resolvedItem.Fullname -eq $OutputPath) {
					Write-Error "Careful there - don't overwrite your original" -targetObject $resolvedPath
					continue
				}
				if ((Test-Path $OutputPath) -and !$Force) {
					if (!$PSCmdlet.ShouldContinue($relOutput, "File already exists. Overwrite?")) {
						continue
					}
					Remove-Item $OutputPath -Confirm:$false
				}
				$tmpDir = "$env:Temp\$($resolvedItem.BaseName)"
				if (Test-Path $tmpDir) {
					Remove-Item -Recurse -Force:$Force $tmpDir -Confirm:$false # make sure we start with a clean slate
				}
				Expand-Archive $resolvedPath -DestinationPath $tmpDir -Force:$Force
				Get-ChildItem $tmpDir -Recurse -Include *.xml | Foreach-Object {
					$fullname = $_.fullname
					(Get-Content -Raw -Encoding utf8 -LiteralPath $fullname) -replace 'lang="de-DE"', 'lang="en-US"' |
						Set-Content -Literalpath $fullname -Encoding utf8 -NoNewline -Confirm:$false
				}
				Compress-Archive -Path $tmpDir\* -DestinationPath $OutputPath -Force:$Force 
				Remove-Item -Recurse -Force:$Force $tmpDir -Confirm:$false
				Get-Item $OutputPath
			}
		}
	}
}

Register-ArgumentCompleter -Command Set-PowerPointLanguage -Parameter Path -ScriptBlock {
	param($c, $p, $w, $a, $fb)
	Get-ChildItem -Recurse -Include *.pptx -Depth 2 | Where-Object Name -like $w* | Where-object Name -notmatch '.\w\w-\w\w\.pptx$' | foreach-Object {
		[string]$rel = Resolve-path -Relative $_.fullname
		$c = if ($rel -match '\s') {	"`"$rel`""} else {$rel}
		[System.Management.Automation.CompletionResult]::new($c, $rel, "ProviderItem", $_.fullname)
	}
}

Register-ArgumentCompleter -Command Set-PowerPointLanguage -Parameter OutputPath -ScriptBlock {
	param($c, $p, $w, $a, $fb)
	. {
		if ($fb.Path) {
			[io.path]::ChangeExtension($fb.Path, ".en-us.pptx")
			[io.path]::ChangeExtension($fb.Path, ".de-de.pptx")
		}
		else {
			"{[io.path]::ChangeExtension(`$_.Fullname, '.en-us.pptx')}"
			"{[io.path]::ChangeExtension(`$_.Fullname, '.de-de.pptx')}"
		}
	} | foreach-Object {
		$cmp = if ($_ -match '\s') {	"`"$_`""} else {$_}
		[System.Management.Automation.CompletionResult]::new($cmp, $_, "ProviderItem", $_)
	}
}