/**
* Processes one line of data passed on to it and digs lowers with it
* First, it saves the current data to this group
* Second it processes all aggregators
* Third it extract the next grouper in line, processes it to get the group from this grouper
* Fourth checks if the group for that grouper already exists, if not creates one, stores it
* Finaly, sends the same arguments to the sub group with one less grouper
*
* Creates a recursive tree of groups where the data references are aggregated and stored for looping
*
* @param mixed $data Data to process in the different groupers and aggregators, this is only one line
* @param mixed $key Key to process in the different groupers and aggregators, this is only one line
* @param mixed \array Array of groupers, only the first one is used, the rest are passed down the current group for further processing
* @param mixed \array Array of aggregators, all processed and values are stored inside the current group result
*
* @access public
*/
public function process($data, $key, array $groupers, array $aggregators)
{
//Add the data to the current group
//Keep a reference, do not copy the data
$this->data[] = $data;
//Process the aggregators
foreach ($aggregators as $aggregator) {
//If the object is not an aggregator
if (!is_object($aggregator) || !$aggregator instanceof AggregatorInterface) {
throw new InvalidArgumentException('Aggregator value resolved from $aggregators array is not an AggregatorInterface object, aborting data processing');
}
//Process the aggregation
$aggregator->aggregate($this, $data, $key);
}
//If there are groupers in the groupers array
if (count($groupers) > 0) {
//Get the next grouper
$grouper = array_shift($groupers);
if (!is_object($grouper) || !$grouper instanceof GrouperInterface) {
throw new InvalidArgumentException('Grouper shifted out of $groupers array is not a GrouperInterface object, aborting data processing');
}
$groupValue = $grouper->getGroupedOnValue($data, $key);
//Check if that groupValue already exists
if ($this->hasGroup($groupValue) == false) {
$newGroup = new self();
$newGroup->setGroupValue($groupValue);
$this->addGroup($newGroup, $groupValue);
}
$group = $this->getGroup($groupValue);
//Process this group with remaining groupers
$group->process($data, $key, $groupers, $aggregators);
}
}
