sandbox.rb in kindergarten-0.1.1

- old
+ new

@@ -1,32 +1,34 @@
 module Kindergarten
   class Sandbox
-    attr_reader :child, :governess, :perimeter, :purpose
+    attr_reader :child, :governess, :perimeters, :purpose
 
     def initialize(child)
       @child     = child
       @governess = Kindergarten::HeadGoverness.new(child)
 
-      @purpose   = {}
-      @perimeter = []
-      def @perimeter.include?(other)
-        (self.collect(&:class) & [ other.class ]).any?
-      end
+      @purpose    = {}
+      @perimeters = []
 
       @unguarded = false
     end
 
     def extend_perimeter(*perimeter_classes)
       perimeter_classes.each do |perimeter_class|
+        if @perimeters.collect(&:class).include?(perimeter_class)
+          # already have this one
+          return
+        end
+
         # if the perimeter specifies a governess, use that - otherwise appoint
         # the head governess
         child     = self.child
         governess = perimeter_class.governess ?
           perimeter_class.governess.new(child) :
           self.governess
 
-        perimeter = perimeter_class.new(child, governess)
+        perimeter = perimeter_class.new(self, governess)
 
         raise ArgumentError.new(
           "Module must inherit from Kindergarten::Perimeter"
         ) unless perimeter.kind_of?(Kindergarten::Perimeter)
 
@@ -35,11 +37,24 @@
         # the head governess must know all the rules
         unless governess == self.governess || perimeter_class.govern_proc.nil?
           self.governess.instance_eval(&perimeter_class.govern_proc)
         end
 
-        @perimeter << perimeter unless @perimeter.include?(perimeter)
+        perimeter_class.subscriptions.each do |purpose, events|
+          if self.purpose[purpose].nil?
+            Kindergarten.warning "#{perimeter_class} has subscriptions on un-loaded purpose :#{purpose}"
+            next
+          end
+
+          events.each do |event, blocks|
+            blocks.each do |block|
+              self.purpose[purpose]._subscribe(event, &block)
+            end
+          end
+        end
+
+        @perimeters << perimeter
       end
     end
     alias_method :load_perimeter, :extend_perimeter
     alias_method :load_module, :extend_perimeter
 
@@ -70,9 +85,47 @@
 
     def disallows?(action, target)
       governess.cannot?(action, target)
     end
     alias_method :disallowed?, :disallows?
+
+    def guard(action, target, opts={})
+      unless allows?(action, target)
+        raise Kindergarten::AccessDenied.new(action, target, opts)
+      end
+    end
+
+    def subscribe(purpose_name, *events, &block)
+      unless (purpose = @purpose[purpose_name.to_sym])
+        Kindergarten.warning "No such purpose has been loaded: #{purpose_name}"
+        return
+      end
+
+      events.each do |event|
+        purpose._subscribe(event, &block)
+      end
+    end
+
+    def unsubscribe(purpose_name, *events)
+      unless (purpose = @purpose[purpose_name.to_sym])
+        Kindergarten.warning "No such purpose has been loaded: #{purpose_name}"
+        return
+      end
+
+      events.each do |event|
+        purpose._unsubscribe(event)
+      end
+    end
+
+    def broadcast(&block)
+      @broadcast = block
+    end
+
+    def broadcast!(event)
+      return if @broadcast.nil?
+
+      @broadcast.call(event)
+    end
 
     # TODO: Find a purpose and call that - move this block to Purpose
     def method_missing(name, *args, &block)
       super
 