Magento2 how to apply layered navigation filters at REST API Level?

Question

I would like to implement below REST API in magento 2

"How to retrieve which layered navigation filters are applied as like in the product list page?"

Can you please suggest me how we can achieve (or) possibilities?

In magento 1 at website level we can get applied filters at list page (list.phtml) by following snippet

$appliedFilters = Mage::getSingleton('catalog/layer')->getState()->getFilters();

(and)

$appliedFilters = Mage::getSingleton(‘Mage_Catalog_Block_Layer_State’)->getActiveFilters();

But in magento 2 at api level how we can implement ?

Answer 1

$this->layerResolver->setCurrentCategory($id);
            $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
            $fill = $objectManager->create('Magento\Catalog\Model\Layer\Category\FilterableAttributeList');
            $filterList = new \Magento\Catalog\Model\Layer\FilterList($objectManager,$fill);
            $filterAttributes = $filterList->getFilters($this->layerResolver);
            $filterArray = array();
            $i = 0;

            foreach($filterAttributes as $filter){
                $availablefilter = (string)$filter->getName(); //Gives Display Name of the filter such as Category,Price etc.
                $items = $filter->getItems(); //Gives all available filter options in that particular filter
                $filterValues = array();
                $j = 0;
                foreach($items as $item){
                   $filterValues[$j]['display'] = strip_tags($item->getLabel());
                   $filterValues[$j]['label'] = $item->getValue();
                   $filterValues[$j]['count'] = $item->getCount(); //Gives no. of products in each filter options
                   $j++;
                }
                if(!empty($filterValues)){
                   $filterArray['availablefilter'][$availablefilter] =  $filterValues;
                }
                $i++;
            }
            return array($filterArray);

I Have implemented same as in list page , but not i need to develop for the search result page , how could i?