How do I get each cart item with their total discount

[JPaulMora]

Hello, im currently integrating Prestashop 1.6 to a custom accounting software, the problem is they only support per item discounts. Any info on how to achieve this would be very helpful, thanks.

Also, while looking for how to manually calculate it, I found the source code for getContextualValue() which seems to do some sort of calculations based on discounts/coupons and other fees, though I couldn't find any resource saying what it does, so any info on this or any other function would be really helpful.