I'm coding a custom module to make shipping by a delivery entreprise which is not having module compatible with drupal commerce.
So, I give choice to customer between 2 shipping methods :
colissimo( french official delivery method ) using existing module.
exapaq ( custom module I try to code ).
This is working but exapaq doesn't deliver to customer's home but to shops or commerces where customers can have their order.
So, after customer select shipping method, I would like to test which is selected and, if this is exapaq, add a new form to allow customer select where he want to go taking its order.
The problem is that I don't have any idea on where can I do this test and how can I insert a new form before to go on order review page.