import objc

from Foundation import *
from AppKit import *
from PyObjCTools import NibClassBuilder


try:
    set
except NameError:
    from sets import Set as set
    
class SelectedObjectsFilteringController(NSArrayController):
    files = objc.ivar('files')
    def awakeFromNib(self):
        print "ADD OBSERVER", self.files
        self.files.addObserver_forKeyPath_options_context_(
            self,
            'selectedObjects',
            NSKeyValueObservingOptionNew,
            0)

    def observeValueForKeyPath_ofObject_change_context_(
        self, keypath, obj, change, context):
        print "OBSERVE"
        self.rearrangeObjects()

    def arrangeObjects_(self, objects):
        try:
            selected = set(self.valueForKeyPath_('files.selectedObjects.fileName'))
            print "ARRANGE OBJ"
            if selected:
                #print "BE4", len(objects), objects
                objects = [dct for dct in objects if dct and dct['fileName'] in selected]
                #print "AF", len(objects), objects
            if len(objects) == 0:
                return None
            return NSArray.arrayWithArray_(objects)
        except Exception, e:
            import traceback; traceback.print_exc()
            raise e