Refactor thesaurus query build

- Look for text nodes and infer the concepts behind term using thesaurus
- Use value objects for thesaurus terms and concepts
- Pass a QueryContext holding allowed fields and locales informations when building the Elasticsearch query
- Change type hinting and name of query building method on nodes
- Remove unused method Node#isFullTextOnly()
- Move getFieldsStructure from RecordIndexer to RecordHelper for reusing field structure in SearchEngine

lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/TextNode.php

@@ -2,23 +2,43 @@
 
 namespace Alchemy\Phrasea\SearchEngine\Elastic\AST;
 
-class TextNode extends Node
+use Alchemy\Phrasea\SearchEngine\Elastic\Search\QueryContext;
+use Alchemy\Phrasea\SearchEngine\Elastic\Thesaurus\TermInterface;
+
+class TextNode extends Node implements TermInterface
 {
     protected $text;
+    protected $concepts = array();
 
     public function __construct($text)
     {
         $this->text = $text;
     }
 
-    public function getQuery($fields = ['_all'])
+    public function setConcepts(array $concepts)
     {
-        return array(
+        $this->concepts = $concepts;
+    }
+
+    public function buildQuery(QueryContext $context)
+    {
+        $query = array(
             'multi_match' => array(
-                'fields'    => $fields,
+                'fields'    => $context->getLocalizedFields(),
                 'query'     => $this->text,
             )
         );
+
+        if ($this->concepts) {
+            $shoulds = array($query);
+            foreach ($this->concepts as $concept) {
+                $shoulds[]['term']['concept_paths'] = $concept->getPath();
+            }
+            $query = array();
+            $query['bool']['should'] = $shoulds;
+        }
+
+        return $query;
     }
 
     public function getTextNodes()
@@ -31,13 +51,22 @@ class TextNode extends Node
         return sprintf('"%s"', $this->text);
     }
 
-    public function isFullTextOnly()
-    {
-        return true;
-    }
 
-    public function getText()
+    // Implementation of TermInterface
+
+    public function getValue()
     {
         return $this->text;
     }
+
+    public function hasContext()
+    {
+        return false;
+    }
+
+    public function getContext()
+    {
+        // TODO Insert context during parsing
+        return null;
+    }
 }