How does one use PHP to parse mail headers?

[Faisal Humayun]

Hello!

I am very new to PHP (or any type of scripting language), and am trying to
write a PHP script that will accept email headers posted into a form.

Upon submission, the script needs to parse the time, date, and mail server
info. In the end, it should respond with how much of a delay it took for
the original message.

Please check out the following link for an idea of a sample output:

http://198.104.182.189/php-scripts/emaildelay.htm

Any pointers, references, functions, sample parsers would be immensely
appreciated!

Thanks so much for your kind attention.
Respectfully,
Faisal