What are the chatbot services or libraries?

Question

Computer networks

I am engaged in the creation of one service that needs a chat bot that imitates a character.
I would like the character to have a slightly more complex analysis of the input text than "find a keyword in the user's phrase and return the corresponding phrase in response."
Probably, there are ready-made solutions for this task, can you advise something?
Apart from home crafts, I found only one similar product - information from Nanosemantics, but the pricing did not suit me there.
Interested in both free and paid options. Both in the form of services, and in the form of PHP libraries. Or even not PHP.
Clarifications:
Language - Russian.
You need the ability to create multiple characters and customize them individually. Ideally, some kind of administrative interface for non-programmers to configure (like iii.ru)

Answer 1

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