Add discount to single product in cart - magento

Question

After struggling attempting to fix a bundle price whilst remaining VAT calculations, my next attempt to resolve the issue is to apply a discount to the bundle to reduce it to the fixed amount.
<?php
class XXX_Fixedbundlediscount_Model_Observer
{
public function setDiscount($observer)
{
Mage::log('settingDiscount');
$quote = $observer->getEvent()->getQuote();
$quoteid = $quote->getId();
if ($quoteid) {
foreach ($quote->getAllItems() as $item) {
$product = $item->getProduct();
$fixed_price_attribute = (float)Mage::getResourceModel('catalog/product')->getAttributeRawValue($product->getId(), 'giftset_fixed_price', Mage::app()->getStore()->getStoreId());
if ($product->getTypeId() !== Mage_Catalog_Model_Product_Type::TYPE_BUNDLE || !$fixed_price_attribute) {
continue;
}
$lineTotal = (float)$item->getPriceInclTax();
$item->setBaseDiscountAmount(0);
$item->setDiscountAmount(0);
if ($lineTotal > $fixed_price_attribute) {
$item->setDiscountAmount(-($lineTotal - $fixed_price_attribute));
$item->setDiscountDescription('Gift Set');
$item->setBaseDiscountAmount(-($lineTotal - $fixed_price_attribute))->save();
Mage::log('xxxx');
}
Mage::log($fixed_price_attribute);
Mage::log($lineTotal);
Mage::log(($fixed_price_attribute > $lineTotal) ? 'Yes' : 'No');
}
}
}
}
I've set up a custom attribute on the Bundled products which specifies the fixed cost. As you can see from the above, the idea is to detect this, calculate the cost of the bundle and add the difference of that between the attribute value as a discount.
Unfortunately it's not adding any discounts what so ever...
Can any one suggest anything that may be of any use?
Thanks
Gav

Answer 1

I managed to find a way in the end:
<?php
class XXX_Fixedbundlediscount_Model_Observer
{
public function setDiscount($observer)
{
$quote = $observer->getEvent()->getQuote();
$quoteid = $quote->getId();
$discountAmount = 0;
if ($quoteid) {
foreach ($quote->getAllItems() as $item) {
$product = $item->getProduct();
$fixed_price_attribute = (float)Mage::getResourceModel('catalog/product')->getAttributeRawValue($product->getId(), 'giftset_fixed_price', Mage::app()->getStore()->getStoreId());
if ($product->getTypeId() !== Mage_Catalog_Model_Product_Type::TYPE_BUNDLE || !$fixed_price_attribute) {
continue;
}
if ($item->getPriceInclTax() > $fixed_price_attribute) {
$discountAmount += $item->getQty() * ($item->getPriceInclTax() - $fixed_price_attribute);
}
}
if ($discountAmount > 0) {
$total = $quote->getBaseSubtotal();
$quote->setSubtotal(0);
$quote->setBaseSubtotal(0);
$quote->setSubtotalWithDiscount(0);
$quote->setBaseSubtotalWithDiscount(0);
$quote->setGrandTotal(0);
$quote->setBaseGrandTotal(0);
$canAddItems = $quote->isVirtual() ? ('billing') : ('shipping');
foreach ($quote->getAllAddresses() as $address) {
$address->setSubtotal(0);
$address->setBaseSubtotal(0);
$address->setGrandTotal(0);
$address->setBaseGrandTotal(0);
$address->collectTotals();
$quote->setSubtotal((float)$quote->getSubtotal() + $address->getSubtotal());
$quote->setBaseSubtotal((float)$quote->getBaseSubtotal() + $address->getBaseSubtotal());
$quote->setSubtotalWithDiscount(
(float)$quote->getSubtotalWithDiscount() + $address->getSubtotalWithDiscount()
);
$quote->setBaseSubtotalWithDiscount(
(float)$quote->getBaseSubtotalWithDiscount() + $address->getBaseSubtotalWithDiscount()
);
$quote->setGrandTotal((float)$quote->getGrandTotal() + $address->getGrandTotal());
$quote->setBaseGrandTotal((float)$quote->getBaseGrandTotal() + $address->getBaseGrandTotal());
$quote->save();
$quote->setGrandTotal($quote->getGrandTotal() - ($discountAmount / 2))
->setBaseGrandTotal($quote->getBaseGrandTotal() - $discountAmount)
->setSubtotalWithDiscount($quote->getSubtotalWithDiscount() - $discountAmount)
->setBaseSubtotalWithDiscount($quote->getBaseSubtotalWithDiscount() - $discountAmount)
->save();
if ($address->getAddressType() == $canAddItems) {
$address->setSubtotalWithDiscount((float)$address->getSubtotalWithDiscount() - $discountAmount);
$address->setGrandTotal((float)$address->getGrandTotal() - $discountAmount);
$address->setBaseSubtotalWithDiscount((float)$address->getBaseSubtotalWithDiscount() - $discountAmount);
$address->setBaseGrandTotal((float)$address->getBaseGrandTotal() - $discountAmount);
if ($address->getDiscountDescription()) {
$address->setDiscountAmount(-($address->getDiscountAmount() - $discountAmount));
$address->setDiscountDescription($address->getDiscountDescription() . ', Gift Sets');
$address->setBaseDiscountAmount(-($address->getBaseDiscountAmount() - $discountAmount));
} else {
$address->setDiscountAmount(-($discountAmount));
$address->setDiscountDescription('Gift Sets');
$address->setBaseDiscountAmount(-($discountAmount));
}
$address->save();
}
}
foreach ($quote->getAllItems() as $item) {
$product = $item->getProduct();
$fixed_price_attribute = (float)Mage::getResourceModel('catalog/product')->getAttributeRawValue($product->getId(), 'giftset_fixed_price', Mage::app()->getStore()->getStoreId());
if ($product->getTypeId() !== Mage_Catalog_Model_Product_Type::TYPE_BUNDLE || !$fixed_price_attribute) {
continue;
}
$lineDiscount = 0;
if ($item->getPriceInclTax() > $fixed_price_attribute) {
$lineDiscount = $item->getQty() * ($item->getPriceInclTax() - $fixed_price_attribute);
}
$item->setDiscountAmount($lineDiscount);
$item->setBaseDiscountAmount($lineDiscount)->save();
}
}
}
}
}
The above simply allows the bundled product to remain dynamic whilst having a fixed price. If the dynamic value is more than the fixed price, it will add a discount to reduce it back to the fixed price.
I'll update this shortly with code that excludes extra products added to the bundle.