reg.ps1

function Write-RegistryOutput {
	param (
		[hashtable] $Keys
	)

	$Roots = @{
		HKCR = "HKEY_CLASSES_ROOT"
		HKCU = "HKEY_CURRENT_USER"
		HKLM = "HKEY_LOCAL_MACHINE"
	}

	function escape {
		param (
			[string] $value
		)

		$value -replace '\\', '\\' -replace '"', '\"'
	}

	function FmtValue {
		param (
			[string] $value
		)

		if ($value.GetType().Name -eq 'String') {
			# Write out just a default string
			"`"$(escape $value)`""
		} elseif ($value.GetType().Name -eq 'Int32') {
			"dword:$value"
		}
		<#
		The rest use hex representations
		They're of the form hex(x):00,01,02
		Where x can be:
		  * 2 - Expandable String
		  * 7 - Multi-String (three 00s for a newline, two 00s for the end)
		  * b - QWORD
		Binary has no "(x)" part at all.
		#>
	}

	$written = @{}
	$out = "Windows Registry Editor Version 5.00"
	$Keys.GetEnumerator() | Sort-Object Name | ForEach-Object {
		$parts = $_.Key -split '\\'
		$root, $rest = $parts
		if ($Roots[$root]) { $root = $Roots[$root] }
		$val = $_.Value

		# Write out any empty headers needed, plus the needed header
		$rest | ForEach-Object {
			$root += "\$_"
			if (! $written[$root]) {
				$written[$root] = $true
				$out += "`n`n[$root]"
			}
		}

		$tmp = if ($val.GetType().Name -eq 'Hashtable') {
			@(
				'', '@', '(Default)' | ForEach-Object {
					if ($val[$_]) {
						$ret = "@=$(FmtValue $val[$_])" 
						Write-Host $val[$_]
						$val.Remove($_)
						$ret
					}
				}
			) + (
				$val.GetEnumerator() | Sort-Object Name | ForEach-Object {
					"`"$(escape $_.Key)`"=$(FmtValue $_.Value)"
				}
			) -join "`n"
		} else {
			# Write out just a default value
			"@=`"$(escape $val)`""
		}
		$out += "`n$tmp"
	}
	$out
}

function Import-RegistryFile {
	param (
		[string] $Path
	)
	
	if (Start-Process reg -ArgumentList "import $Path" -Verb runAs) {
		Remove-Item -Path $Path
	}
}