Open a support ticket in case of invoice overpayment

[evcz]

Hi,

 

I'm looking for a hook to open a support ticket under user account in case of invoice overpayment

 

Basically what I would like to do is:

 

hook to addinvoicepayment

everytime addinvoicepayment is called check if the invoice paid amount is > of the total amount.

if it is: open a ticket to that user

 

Is there some example code I could start with?

(how do I check invoices amount and so on within hooks?)

 

Thanks