Install in LocalAppData on Windows #1592

# Here be P/Invoke...
$Shell32 = ([System.Management.Automation.PSTypeName]'Win32.Shell32').Type;

if (-not $Shell32) {
    # The PreserveSig = false setting automatically unmarshals the return value.
    $signature = @'
[DllImport("shell32.dll", CharSet = System.Runtime.InteropServices.CharSet.Unicode, ExactSpelling = true, PreserveSig = false)]
public static extern string SHGetKnownFolderPath(
     ref Guid rfid,
     uint dwFlags,
     IntPtr hToken
     );
'@

    $typeArgs = @{
        MemberDefinition = $signature
        Name = "Shell32"
        Namespace = "Win32"
        PassThru = $true
    };
    $Shell32 = Add-Type @typeArgs;
}

# GUID for FOLDERID_UserProgramFiles known folder: {5CD7AEE2-2219-4A67-B85D-6C9CE15660CB}
# $guid = [System.Guid]::ParseExact("{5CD7AEE2-2219-4A67-B85D-6C9CE15660CB}", "B")
# $guid = [guid]"{5CD7AEE2-2219-4A67-B85D-6C9CE15660CB}"
$guid = [System.Guid]::new(0x5CD7AEE2, 0x2219, 0x4A67, 0xB8, 0x5D, 0x6C, 0x9C, 0xE1, 0x56, 0x60, 0xCB);
# The flag in the second argument tells Windows to create the folder if it doesn't exist
# The null pointer as the third argument means we get the known folder path for the current user
$path = $Shell32::SHGetKnownFolderPath([ref]$guid, 0x00008000, [IntPtr]::Zero);
return $path;