Ghostscript rotate pages

I use Ghostscript to convert PDF documents to PCL for printing. Recently I have the additional requirement that all pages must be rotated to Portrait before printing. I have found a way to do so using Ghostscript with following command and postscript function.

"C:\Program Files (x86)\gs\bin\gswin32c.exe" "-dNOPAUSE" "-dNOPROMPT" "-dBATCH" "-sDEVICE=pxlmono" "-Ic:\Program Files (x86)\gs\fonts\;c:\Program Files (x86)\gs\lib\;c:\Program Files (x86)\gs\lib\;" "-r300" "-sOutputFile=C:\EXPORTFILE_e542e04f-5e84-4c8e-9b41-55480cd5ec52.cache" "rotate612x792.ps" "C:\EXPORTFILE_3a5de9da-d9ca-4562-8cb6-10fb8715385a.cache"

Contents of rotate612x792.ps

%! Rotate Pages
<< /Policies << /PageSize 5 >> 
   /PageSize [612 792] 
   /InputAttributes currentpagedevice 
   /InputAttributes get mark exch {1 index /Priority eq not {pop << /PageSize [612 792] >>} if }  forall >>
   >> setpagedevice

The problem is that this function replaces all page sizes with letter size. My documents are sometimes legal or A4. I have tried to modify this function to replace landscape sizes with their portrait counterpart, but have not been able to produce functioning postscript. I need to be pointed in the right direction to produce the postscript equivalent of the following pseudo code.

for(each page)
{
   if(PageSize == [792 612])
       PageSize = [612 792];
}

I am aware that there are non-Ghostscript ways of rotating pages, but if I can get this to work it would fit nicely into my process and would not reduce performance.

Here is a sample of one of my pdf files: Sample1.pdf

I found a workable solution. It is not as versatile as I hoped, but it hits all my requirements.

The following postscript script will rotate A4, Letter and Legal documents to Portrait. To get it to do other page sizes adjust the min and max sizes.

%!PS
  %   Sequence to set up for a single page size, auto fit all pages.
  %   Autorotate A4 Letter and Legal page sizes to Portrait
  << /Policies << /PageSize 3 >>
     /InputAttributes currentpagedevice /InputAttributes get    %current dict
     dup { pop 1 index exch undef } forall    % remove all page sizes
     dup 0 << /PageSize [ 595 0 612 99999 ] >> put    % [ min-w min-h max-w max-h ]
  >> setpagedevice

This postscript script will rotate A4, Letter and Legal documents to Landscape. The only difference is the Min/Max page size values.

%!PS
  %   Sequence to set up for a single page size, auto fit all pages.
  %   Autorotate A4 Letter and Legal page sizes to Landscape
  << /Policies << /PageSize 3 >>
     /InputAttributes currentpagedevice /InputAttributes get    %current dict
     dup { pop 1 index exch undef } forall    % remove all page sizes
     dup 0 << /PageSize [ 0 595 99999 612 ] >> put    % [ min-w min-h max-w max-h ]
  >> setpagedevice

This solution is based off the auto-rotate.ps file I found in the source code for the hylafax project. That project appears to be licensed under BSD.