PDF file in browser, split pages by feature?

Question

Programming

Good morning! There is a need to simplify your life) Every morning a PDF file is generated in the browser. There are always a different number of pages, there are only 2 types of pages in the file with clear separating features. It is necessary to ignore pages with sign A and memorize them with sign B, so that later they can be printed using regular means from the browser, or just write the number of pages with sign B to the file.
Ideally, there would be a ready-made solution, or a hint where to dig.
Only familiar with PHP.
Thank you!

Answer 1

There was a slightly similar task, the PDFs were of the old version 1.3 or 1.4.
I didn’t find anything in PHP, I used the CAM::PDF Perl library I
didn’t deal with Perl before, but the entry threshold is low, if you have experience with regular expressions,
hyperpolyglot.org is enough (it used to be more convenient: PERL and PHP were on the same page )