This is a straight port of the Eliza chatbot therapist to PHP.
Based very closely on this Python implementation: https://www.smallsurething.com/implementing-the-famous-eliza-chatbot-in-python/
The main.php file is a basic CLI that lets you talk to Eliza.
Alternatively, you can use the Crell\Eliza class as a library within another application. The only API call is analyze(string), which will return a string response from Eliza.
This library is released under the MIT license.