Gesture recognition before NSGestureRecognizer

gistfile1.m

- (void)mouseDown:(NSEvent *)downEvent {
    CGFloat doubleClickTime = [NSEvent doubleClickInterval]   ;
    NSEventMask eventMask = NSLeftMouseDraggedMask | NSLeftMouseUpMask;
    // Is this a singe, double or triple click? Or long click, or a drag?
    NSEvent *nextEvent = [NSApp nextEventMatchingMask:eventMask untilDate:[NSDate dateWithTimeIntervalSinceNow:doubleClickTime] inMode:NSEventTrackingRunLoopMode dequeue:YES];
    if (nextEvent) {
        // could be an up or a drag
        if (nextEvent.type == NSLeftMouseUp) {
            // got at least a single click, make sure it's not performing a double click
            if ( (nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseDownMask untilDate:[NSDate dateWithTimeIntervalSinceNow:doubleClickTime] inMode:NSEventTrackingRunLoopMode dequeue:YES]) ) {
                // start of a double (or triple) click
                if ( (nextEvent = [NSApp nextEventMatchingMask:eventMask untilDate:[NSDate dateWithTimeIntervalSinceNow:doubleClickTime] inMode:NSEventTrackingRunLoopMode dequeue:YES]) ) {
                    if (nextEvent.type == NSLeftMouseUp) {
                        // got at least a double click, make sure user is not performing a triple click
                        if ( (nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseDownMask untilDate:[NSDate dateWithTimeIntervalSinceNow:doubleClickTime] inMode:NSEventTrackingRunLoopMode dequeue:YES]) ) {
                            // start of a triple click?
                            if ( (nextEvent = [NSApp nextEventMatchingMask:eventMask untilDate:[NSDate dateWithTimeIntervalSinceNow:doubleClickTime] inMode:NSEventTrackingRunLoopMode dequeue:YES]) ) {
                                if (nextEvent.type == NSLeftMouseUp) {
                                    // triple click! This is as far as we care about
                                    [self handleTripleClick];
                                } else {
                                    // double click and drag. That means nothing to us. Eat all events until we get a mouse up
                                    nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseUp untilDate:nil inMode:NSEventTrackingRunLoopMode dequeue:YES];
                                    [NSApp discardEventsMatchingMask:NSAnyEventMask beforeEvent:nextEvent];
                                }
                            } else {
                                // double click and a half. That means nothing to us. Eat all events until we get a mouse up
                                nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseUp untilDate:nil inMode:NSEventTrackingRunLoopMode dequeue:YES];
                                [NSApp discardEventsMatchingMask:NSAnyEventMask beforeEvent:nextEvent];
                            }
                        } else {
                            // double click!
                            [self handleDoubleClick];
                        }
                    } else {
                        // tap and a drag, That means nothing to us. Eat all events until we get a mouse up
                        nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseUp untilDate:nil inMode:NSEventTrackingRunLoopMode dequeue:YES];
                        [NSApp discardEventsMatchingMask:NSAnyEventMask beforeEvent:nextEvent];
                    }
                } else {
                    // tap and a half. That means nothing to us. Eat all events until we get a mouse up
                    nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseUp untilDate:nil inMode:NSEventTrackingRunLoopMode dequeue:YES];
                    [NSApp discardEventsMatchingMask:NSAnyEventMask beforeEvent:nextEvent];
                }
            } else {
                // This is a single click. This view doesn't care about single clicks, but perhaps the superview cares.
                [NSApp postEvent:nextEvent atStart:YES];
                [super mouseDown:downEvent];
            }
        } else {
            [NSApp postEvent:nextEvent atStart:YES];
            [self handleMouseDragWithEvent:downEvent];
        }
    } else {
        // a long single click
        [self handleLongClick];
        // eat all events until we get a mouse up
        nextEvent = [NSApp nextEventMatchingMask:NSLeftMouseUp untilDate:nil inMode:NSEventTrackingRunLoopMode dequeue:YES];
        [NSApp discardEventsMatchingMask:NSAnyEventMask beforeEvent:nextEvent];
    }
}