Q. What are total models responsible for in Magento? Quote, invoice, creditmemo - discount - grand total - shipping - subtotal - tax - nominal - custbalance - freeshipping dispatches event “sales_quote_address_discount_item” in collect method of Mage_Sales_Model_Quote_Address_Total_* ————- Mage/Sales/Model/Quote/Address/Total/Collector.php getCollectors() – Get total models array ordered for right *calculation logic*…
Q. Which class runs total models processing?
Mage_SalesRule_Model_Validator::process() (applies and processes rules for each item of total models)
Basically, rules are sorted by the priority and Magento applies rule by rule for each item