Add hook service for registering callbacks

This may be used by plug-ins to register callback for hooks defined in the core.

app/assets/javascripts/angular/services/hook-service.js

@@ -0,0 +1,62 @@
+//-- copyright
+// OpenProject is a project management system.
+// Copyright (C) 2012-2014 the OpenProject Foundation (OPF)
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License version 3.
+//
+// OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+// Copyright (C) 2006-2013 Jean-Philippe Lang
+// Copyright (C) 2010-2013 the ChiliProject Team
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+//
+// See doc/COPYRIGHT.rdoc for more details.
+//++
+
+angular.module('openproject.services')
+
+.service('HookService', [function() {
+  var hooks = { };
+
+  HookService = {
+    register: function(id, callback) {
+      if (callback && typeof(callback) == "function") {
+        if (!hooks[id]) {
+          hooks[id] = [];
+        }
+
+        hooks[id].push(callback);
+      }
+    },
+    call: function(id, params) {
+      var results = [];
+
+      if (hooks[id]) {
+        for (var x = 0; x < hooks[id].length; x++) {
+          var result = hooks[id][x](params);
+
+          if (result) {
+            results.push(result);
+          }
+        }
+      }
+
+      return results;
+    }
+  };
+
+  return HookService;
+}]);