[enh] preferences added

searx/webapp.py

         response.headers.add('Content-Disposition', 'attachment;Filename=searx_-_{0}.csv'.format('_'.join(query.split())))
         return response
 
-    template = render('results.html'
-                        ,results=results
-                        ,q=request_data['q']
-                        ,selected_categories=selected_categories
-                        ,number_of_results=len(results)
-                        ,suggestions=suggestions
-                        )
-    resp = make_response(template)
-    resp.set_cookie('categories', ','.join(selected_categories))
+    return render('results.html'
+                 ,results=results
+                 ,q=request_data['q']
+                 ,selected_categories=selected_categories
+                 ,number_of_results=len(results)
+                 ,suggestions=suggestions
+                 )
 
-    return resp
 
 @app.route('/about', methods=['GET'])
 def about():
     global categories
     return render('about.html', categs=categories.items())
 
+
+@app.route('/preferences', methods=['GET', 'POST'])
+def preferences():
+
+    if request.method=='POST':
+        selected_categories = []
+        for pd_name,pd in request.form.items():
+            if pd_name.startswith('category_'):
+                category = pd_name[9:]
+                if not category in categories:
+                    continue
+                selected_categories.append(category)
+        if selected_categories:
+            template = render('preferences.html', selected_categories=selected_categories)
+            resp = make_response(template)
+            resp.set_cookie('categories', ','.join(selected_categories))
+            return resp
+    return render('preferences.html')
+
+
 @app.route('/stats', methods=['GET'])
 def stats():
     global categories
     stats = get_engines_stats()
     return render('stats.html', stats=stats)
 
+
 @app.route('/robots.txt', methods=['GET'])
 def robots():
     return Response("""User-agent: *
 Disallow: /stats
 """, mimetype='text/plain')
 
+
 @app.route('/opensearch.xml', methods=['GET'])
 def opensearch():
     global opensearch_xml