Bug 248795 Menu item 'Refresh Remote Calendars' should be disabled when there are no remote calendars

calendar/base/public/calICalendar.idl

@@ -80,6 +80,11 @@ interface calICalendar : nsISupports
    */
   attribute boolean readOnly;
 
+  /**
+   * Whether or not it makes sense to call refresh() on this calendar.
+   */
+  readonly attribute boolean canRefresh;
+
   /** 
    * In combination with the other parameters to getItems(), these
    * constants provide for a very basic filtering mechanisms for use

calendar/providers/caldav/calDavCalendar.js

@@ -146,6 +146,11 @@ calDavCalendar.prototype = {
         this.mReadOnly = bool;
     },
 
+    get canRefresh() {
+        // refresh() is currently not implemented, but we may want to change that
+        return false;
+    },
+
     // attribute nsIURI uri;
     mUri: null,
     get uri() { return this.mUri; },

calendar/providers/composite/calCompositeCalendar.js

@@ -272,6 +272,10 @@ calCompositeCalendar.prototype = {
         throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
     },
 
+    get canRefresh() {
+        return true;
+    },
+
     // void addObserver( in calIObserver observer );
     mCompositeObservers: Array(),
     mObservers: Array(),

calendar/providers/ics/calICSCalendar.js

@@ -125,6 +125,10 @@ calICSCalendar.prototype = {
         this.mReadOnly = bool;
     },
 
+    get canRefresh() {
+        return true;
+    },
+
     mUri: null,
     get uri() { return this.mUri },
     set uri(aUri) {

calendar/providers/memory/calMemoryCalendar.js

@@ -112,6 +112,10 @@ calMemoryCalendar.prototype = {
         this.mReadOnly = bool;
     },
 
+    get canRefresh() {
+        return false;
+    },
+
     // attribute nsIURI uri;
     mUri: null,
     get uri() { return this.mUri; },

calendar/providers/storage/calStorageCalendar.js

@@ -271,6 +271,10 @@ calStorageCalendar.prototype = {
         this.mReadOnly = bool;
     },
 
+    get canRefresh() {
+        return false;
+    },
+
     mURI: null,
     // attribute nsIURI uri;
     get uri() { return this.mURI; },

calendar/resources/content/calendarManagement.js

@@ -64,6 +64,11 @@ var calCalendarManagerObserver = {
         setCalendarManagerUI();
         document.getElementById("new_command").removeAttribute("disabled");
         document.getElementById("new_todo_command").removeAttribute("disabled");
+
+        if (aCalendar.canRefresh) {
+            var remoteCommand = document.getElementById("reload_remote_calendars");
+            remoteCommand.removeAttribute("disabled");
+        }
     },
 
     onCalendarUnregistering: function(aCalendar) {
@@ -78,6 +83,19 @@ var calCalendarManagerObserver = {
                 document.getElementById("new_todo_command").setAttribute("disabled", true);
             }
         }
+
+        if (aCalendar.canRefresh) {
+            // We may have just removed our last remote cal.  Then we'd need to
+            // disabled the reload-remote-calendars command
+            var calendars = getCalendarManager().getCalendars({});
+            function calCanRefresh(cal) {
+                return (cal.canRefresh && !cal.uri.equals(aCalendar.uri));
+            }
+            if (!calendars.some(calCanRefresh)) {
+                var remoteCommand = document.getElementById("reload_remote_calendars");
+                remoteCommand.setAttribute("disabled", true);
+            }
+        }
     },
 
     onCalendarDeleting: function(aCalendar) {
@@ -192,7 +210,12 @@ function setCalendarManagerUI()
     var composite = getDisplayComposite();
     var calmgr = getCalendarManager();
     var calendars = calmgr.getCalendars({});
+    var hasRefreshableCal = false;
     for each (var calendar in calendars) {
+        if (calendar.canRefresh) {
+            hasRefreshableCal = true;
+        }
+
         var listItem = document.createElement("listitem");
 
         var checkCell = document.createElement("listcell");
@@ -220,6 +243,12 @@ function setCalendarManagerUI()
         if (calendarList.selectedIndex == -1)
             calendarList.selectedIndex = 0;    
     }
+    var remoteCommand = document.getElementById("reload_remote_calendars");
+    if (!hasRefreshableCal) {
+        remoteCommand.setAttribute("disabled", true);
+    } else {
+        remoteCommand.removeAttribute("disabled");
+    }
 }
 
 function onCalendarListSelect() {