Custom way to calculate delivery cost

[safius]

I have created my own module to calculate delivery costs based on the distance between the store and the customer's address and to then store it in the database for future reference.

My problem now is that I want to replace the way PS handles shipping in a way that will integrate with PS's other features, say, coupons and the email system. I want my custom-calculated shipping cost to be available wherever a shipping cost is needed without manually replacing it.

Is there a way to achieve this or do I have to change everything by hand?

Edited June 19, 2016 by safius (see edit history)