observable.rb in openwferu-0.9.11

- old
+ new
@@ -51,32 +51,89 @@
 
         #
         # Observers will register themselves to the Observable via
         # this method.
         #
-        def add_observer (channel, &callback)
-            (@observers[channel] ||= []) << callback
+        # An observer is an instance which responds to call(channel, *args)
+        #
+        def add_observer (channel, observer=nil, &callback)
+            observer = callback unless observer
+            (@observers[channel] ||= []) << observer
         end
 
+        #
+        # Removes an observer (this obviously doesn't work well when 
+        # the actual observer is a block).
+        # If a channel is given, the observer will only get removed when
+        # registered for that channel.
+        #
+        def remove_observer (observer, channel=nil)
+
+            channels = if channel
+                [ channel ]
+            else
+                @observers.keys
+            end
+
+            channels.each do |c|
+                do_remove_observer observer, c
+            end
+        end
+
         protected
 
             #
             # Observable classes do call this method to notify their
-            # observers
+            # observers.
             #
+            # Returns true if there was an observer registered.
+            #
             def onotify (channel, *args)
-                do_notify(channel, channel, *args)
+
                 do_notify(:all, channel, *args)
+                do_notify(channel, channel, *args)
             end
 
         private
 
+            def do_remove_observer (observer, channel)
+
+                observers = @observers[channel]
+                observers.delete(observer) if observers
+            end
+
             def do_notify (target_channel, channel, *args)
-                if @observers[target_channel]
-                    @observers[target_channel].each do |obs|
-                        obs.call channel, *args
+
+                if target_channel.is_a?(String)
+
+                    observers = []
+
+                    @observers.each do |c, o|
+
+                        if c.is_a?(String)
+                            next unless target_channel.match(c)
+                        elsif c.is_a?(Regexp)
+                            next unless c.match(target_channel)
+                        else
+                            next
+                        end
+
+                        observers = observers + o
                     end
+                else
+
+                    observers = @observers[target_channel]
                 end
+
+                return false unless observers
+
+                observers.each do |obs|
+                    obs.call channel, *args
+                end
+
+                observers.size > 0
+                    #
+                    # returns true if at least one observer was called
             end
     end
 end
 