Which Price function is called when product is added to cart in magento?

Question

I need to know which price function is called when product is added to cart as i have overridden the function getFinalPrice() but still when product is added to cart it takes the default price. Why ?

Thanks

Answer 1

You can change the product price while add to cart via Event to listen to checkout_cart_product_add_after by following code:
In your /app/code/local/{namespace}/{yourmodule}/etc/config.xml:

<config>
...
<frontend>
    ...
    <events>
        <checkout_cart_product_add_after>
            <observers>
                <unique_event_name>
                    <class>{{modulename}}/observer</class>
                    <method>modifyPrice</method>
                </unique_event_name>
            </observers>
        </checkout_cart_product_add_after>
    </events>
    ...
</frontend>
...

And then create an Observer class at /app/code/local/{namespace}/{yourmodule}/Model/Observer.php

<?php
class <namespace>_<modulename>_Model_Observer
{
    public function modifyPrice(Varien_Event_Observer $obs)
    {
        // Get the quote item
        $item = $obs->getQuoteItem();
        // Ensure we have the parent item, if it has one
        $item = ( $item->getParentItem() ? $item->getParentItem() : $item );
        // Load the custom price
        $price = $this->_getPriceByItem($item);
        // Set the custom price
        $item->setCustomPrice($price);
        $item->setOriginalCustomPrice($price);
        // Enable super mode on the product.
        $item->getProduct()->setIsSuperMode(true);
    }

    protected function _getPriceByItem(Mage_Sales_Model_Quote_Item $item)
    {
        $price;

        //use $item to determine your custom price.

        return $price;
    }

}

Answer 2

This is depends on your product type. default class is Mage_Catalog_Model_Product_Type_Price.

You can open config.xml in catalog module

<catalog>
        <product>
            <type>
                <simple translate="label" module="catalog">
                    <label>Simple Product</label>
                    <model>catalog/product_type_simple</model>
                    <composite>0</composite>
                    <index_priority>10</index_priority>
                </simple>
                <grouped translate="label" module="catalog">
                    <label>Grouped Product</label>
                    <model>catalog/product_type_grouped</model>
                    <price_model>catalog/product_type_grouped_price</price_model>
                    <composite>1</composite>
                    <allow_product_types>
                        <simple/>
                        <virtual/>
                    </allow_product_types>
                    <index_priority>50</index_priority>
                    <price_indexer>catalog/product_indexer_price_grouped</price_indexer>
                </grouped>

..........

here price_model, tag is the actual price model by product type.