+ // If it's not time to run the updater, then bail immediately.
+ // I'm not sure why this is necessary, but Sparkle seems to be
+ // checking too often.
+ //
+ if (! [self timeToCheck])
+ [[NSApplication sharedApplication] terminate:self];
+
+ // If the screen saver is not running, then launch the updater now.
+ // Otherwise, wait until the screen saver deactivates, and then do
+ // it. This is because if the updater tries to pop up a dialog box
+ // while the screen saver is active, everything goes to hell and it
+ // never shows up. You'd expect the dialog to just map below the
+ // screen saver window, but no.
+
+ if (! [self screenSaverActive]) {
+ [self runUpdater];
+ } else {
+ // Run the updater when the "screensaver.didstop" notification arrives.
+ [[NSDistributedNotificationCenter defaultCenter]
+ addObserver:self
+ selector:@selector(saverStoppedNotification:)
+ name:@"com.apple.screensaver.didstop"
+ object:nil];
+
+ // But I'm not sure I trust that, so also poll every couple minutes.
+ timer = [NSTimer scheduledTimerWithTimeInterval: 60 * 2
+ target:self
+ selector:@selector(pollSaverTermination:)
+ userInfo:nil
+ repeats:YES];
+ }
+}
+
+
+- (BOOL) timeToCheck
+{
+ NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
+ NSTimeInterval interval = [defs doubleForKey:@SUScheduledCheckIntervalKey];
+ NSDate *last = [defs objectForKey:@SULastCheckTimeKey];
+ if (!interval || !last)
+ return YES;
+ NSTimeInterval since = [[NSDate date] timeIntervalSinceDate:last];
+ return (since > interval);
+}
+
+
+// Whether ScreenSaverEngine is currently running, meaning screen is blanked.
+// There's no easy way to determine this other than scanning the process table.
+//
+- (BOOL) screenSaverActive
+{
+ BOOL found = NO;
+ NSString *target = @"/ScreenSaverEngine.app";
+ ProcessSerialNumber psn = { kNoProcess, kNoProcess };
+ while (GetNextProcess(&psn) == noErr) {
+ CFDictionaryRef cfdict =
+ ProcessInformationCopyDictionary (&psn,
+ kProcessDictionaryIncludeAllInformationMask);
+ if (cfdict) {
+ NSDictionary *dict = (NSDictionary *) cfdict;
+ NSString *path = [dict objectForKey:@"BundlePath"];
+ if (path && [path hasSuffix:target])
+ found = YES;
+ CFRelease (cfdict);
+ }
+ if (found)
+ break;
+ }
+ return found;
+}
+
+
+- (void) saverStoppedNotification:(NSNotification *)note
+{
+ [self runUpdater];
+}
+
+
+- (void) pollSaverTermination:(NSTimer *)t
+{
+ if (! [self screenSaverActive])
+ [self runUpdater];
+}
+
+
+- (void) runUpdater
+{
+ if (timer) {
+ [timer invalidate];
+ timer = nil;
+ }
+
+ SUUpdater *updater = [SUUpdater updaterForBundle:
+ [NSBundle bundleForClass:[self class]]];