/**
* Verifies if the chart has a kind of determined product
*
* @param integer|\Gabrieljmj\Cart\Product\ProductInterface $product
* @return boolean
*/
public function has($product)
{
return $product instanceof ProductInterface ? isset($this->products[$product->getId()]) : isset($this->products[$product]);
}
/**
* Returns the price of all products summed
*
* @return integer
*/
public function getPrice()
{
return $this->product->getPrice() * $this->amount;
}