How do you get attributes from multiple groups?

Question

I hope somebody can help with this, i need a way of getting all the attributes from multiple groups and sets. I have accomplished getting the attributes from a single group.

public function getRoomDetails()
    {
        $cache = Mage::app()->getCache();


        $attributeSetId     = Mage::getModel('eav/entity_attribute_set')
            ->getCollection()
            ->addFieldToFilter('attribute_set_name', 'Room')
            ->getFirstItem()
            ->getAttributeSetId();

        $temp = $cache->load ('room-details-'.$attributeSetId);
        if($temp === false) {
            $eavcollection = Mage::getModel('eav/entity_attribute_group')->getCollection();
            $eavcollection->addFieldToFilter('attribute_set_id',array('eq'=>$attributeSetId));

            $propertydetails = $eavcollection
                ->addFieldToFilter('attribute_group_name', array('eq' => 'Features'))
                ->getFirstItem()->getId();
            $cache->save(serialize ($propertydetails),'room-details',array(),3600);
            return $propertydetails;
        }else
        {
            return unserialize ($temp);
        }
    }

But i need to get attributes from another group and another set.

Answer 1

I ended up moving the set of attributes into another group as a full set seemed redundant and just pulling the two groups from that set using the below.

$bills = Mage::getModel('eav/entity_attribute_group')->getCollection()
            ->addFieldToFilter('attribute_group_name', array('eq' => 'Bills Includes'))
            ->getFirstItem()->getId();

        $propertydetails = Mage::getModel('eav/entity_attribute_group')->getCollection()
            ->addFieldToFilter('attribute_group_name', array('eq' => 'Property Details'))
            ->getFirstItem()->getId();

        $attributesCollection = Mage::getResourceModel('catalog/product_attribute_collection');
        $attributesCollection->setAttributeGroupFilter(array($bills,$propertydetails));
        return $attributesCollection;

Answer 2

Getting attribute set ids and using these (left the caching behind to leave that complexity)

$attributeSetCollection = Mage::getModel('eav/entity_attribute_set')
        ->getCollection();

$select = $attributeSetCollection->getSelect();

$select->where('attribute_set_name = ?', 'Get A')
        ->orWhere('attribute_set_name = ?', 'Room')
//        ->orWhere('attribute_set_name = ?', 'And Have')
//        ->orWhere('attribute_set_name = ?', 'Fun')
        ->reset(Zend_Db_Select::COLUMN)
        ->columns('attribute_set_id');

$attributeSetIds = $attributeSetCollection->getConnection()->fetchAll($select);


$attributeCollection = Mage::getModel('eav/entity_group')->getCollection();

$attributeCollection->addFieldToFilter('attribute_set_id', array('in' => $attributeSetIds))
        ->addFieldToFilter('attribute_group_name', array('eq' => 'Features'));

$attributeSetIds = $attributeCollection->getAllIds();

var_dump($attributeSetIds); // Here the are