I'm looking for PHP tool to edit *.eps or *.ai files? I need to add any new shapes or text to these files. Is there any way to do this?
Don't overestimate the complexity of a picture. For PSD files I found the following: http://www.phpclasses.org/package/3627-PHP-Open-images-in-the-PhotoShop-PSD-format.html#download (link is broken; package doesn't exist) In the end the script isn't even very complex. It's just a matter of knowing which bytes to pick. I could imagine that for .ai files, there's something similar...
Recently, .ai files have similar format to PDF (files produced about 2000 and newer). I've successfully opened .ai files with a PDF viewer such as MUPDF after renaming them with a .pdf extension. If this works for you, any PHP tool for PDF files should work for AI files.