Add support for asynchronous / lazy plugins

Fixes #253

js/glowingbear.js

@@ -1343,6 +1343,12 @@ weechat.directive('plugin', function($rootScope) {
                  * Actual plugin content is only fetched when
                  * content is shown.
                  */
+
+                // If the plugin is asynchronous / lazy, execute it now and store
+                // the result. This ensures that the callback is executed only once
+                if ($scope.plugin.content instanceof Function) {
+                    $scope.plugin.content = $scope.plugin.content();
+                }
                 $scope.displayedContent = $scope.plugin.content;
                 $scope.plugin.visible = true;
 

js/plugins.js

@@ -60,8 +60,14 @@ plugins.service('plugins', ['userPlugins', '$sce', function(userPlugins, $sce) {
                 if (num) {
                     pluginName += " " + num;
                 }
+
+                // If content isn't a callback, it's HTML
+                if (!(content instanceof Function)) {
+                    content = $sce.trustAsHtml(content);
+                }
+
                 message.metadata.push({
-                    'content': $sce.trustAsHtml(content),
+                    'content': content,
                     'nsfw': nsfw,
                     'name': pluginName
                 });