handle language for multiselect

lib/Alchemy/Phrasea/Controller/Root/Login.php

@@ -189,6 +189,9 @@ class Login implements ControllerProviderInterface
             'validation_length_min'     => _('This value is too short. It should have %s character or more'),
             'password_match'            => _('The passwords do not match.'),
             'accept_tou'                => _('You must accept the terms of use.'),
+            'none_selected'             => _('None selected'),
+            'collections'               => _('Collections'),
+            'collection'                => _('Collection'),
         ));
 
         $date = new \DateTime();

www/scripts/apps/login/home/common.js

@@ -10,10 +10,11 @@
 define([
     "jquery",
     "underscore",
+    "i18n",
     "backbone",
     "bootstrap",
     "multiselect"
-], function($, _, Backbone, bootstrap, multiselect) {
+], function($, _, i18n, Backbone, bootstrap, multiselect) {
     var initialize = function() {
         // close alerts
         $(document).on("click", ".alert .alert-block-close a", function(e){
@@ -24,7 +25,22 @@ define([
 
         $("select[multiple='multiple']").multiselect({
             buttonWidth : "100%",
-            buttonClass: 'btn btn-inverse'
+            buttonClass: 'btn btn-inverse',
+            buttonText: function(options, select) {
+                if (options.length === 0) {
+                    return i18n.t("none_selected") + '<b class="caret"></b>';
+                }
+                else if (options.length > 4) {
+                    return options.length + (options.length > 1 ? i18n.t("collections") : i18n.t("collection")) + ' <b class="caret"></b>';
+                }
+                else {
+                    var selected = '';
+                    options.each(function() {
+                        selected += $(this).text() + ', ';
+                    });
+                    return selected.substr(0, selected.length -2) + ' <b class="caret"></b>';
+                }
+            }
         });
     };