use Es;

use Log;

        $index = $request->input('index', 0);

        $limit = $request->input('limit', 0);

        $sort = $request->input('sort', 'count');

        if($sort == "count" || $sort == "descending") {

            $order_field = "_count";

            $order_dir = "desc";

        } elseif($sort == "-count") {

            $order_field = "_count";

            $order_dir = "asc";

        } elseif ($sort == "label" || $sort == "alphabetical") {

            $order_field = "_term";

            $order_dir = "asc";

        } elseif ($sort == "-label") {

            $order_field = "_term";

            $order_dir = "desc";

        } else {

            $order_field = "_count";

            $order_dir = "desc";

        $query = [

            'index' => env('ELASTICSEARCH_INDEX'),

            'body' => [

                'size' => 0,

                'aggs' => [

                    "subjects" => [

                        "nested" => [ "path" => "subject" ],

                        "aggs" => [

                            "subjects" => [

                                "terms" => [

                                    "field" => "subject.label_code",

                                    "size" => $limit * ($index+1),

                                    "order" => [ $order_field => $order_dir ]

                                ]

                            ]

                        ]

                    ]

                ]

            ]

        ];

        $esRes = Es::search($query);

        $bucketList = array_slice($esRes['aggregations']['subjects']['subjects']['buckets'], $index*$limit, $limit);

        foreach($bucketList as $bucket) {

            $parts = explode("|", $bucket['key']);

            $label = $parts[0];

            $url = config('corpusparole.bnf_ark_base_url').$parts[1];

            $themes[$url] = [

                "count" => $bucket['doc_count']