lib/joint.rb in joint-0.1.1 vs lib/joint.rb in joint-0.2

@@ -1,70 +1,84 @@
+require 'set'
 require 'mime/types'
 require 'wand'
 
 module Joint
   autoload :Version, 'joint/version'
 
-  def self.file_name(file)
-    file.respond_to?(:original_filename) ? file.original_filename : File.basename(file.path)
-  end
-
   module ClassMethods
     def attachment(name)
-      self.class.class_inheritable_accessor :attachment_names
+      self.class.class_inheritable_accessor :attachment_names unless self.class.respond_to?(:attachment_names)
       self.class.attachment_names ||= []
       self.class.attachment_names << name
 
       after_save     :save_attachments
-      before_destroy :destroy_attached_files
+      after_save     :destroy_nil_attachments
+      before_destroy :destroy_all_attachments
 
       key "#{name}_id".to_sym,   ObjectId
       key "#{name}_name".to_sym, String
       key "#{name}_size".to_sym, Integer
       key "#{name}_type".to_sym, String
 
-      define_method(name) do
-        AttachmentProxy.new(self, name)
-      end
+      class_eval <<-EOC
+        def #{name}
+          @#{name} ||= AttachmentProxy.new(self, :#{name})
+        end
 
-      define_method("#{name}=") do |file|
-        self["#{name}_id"]           = Mongo::ObjectID.new
-        self["#{name}_size"]         = File.size(file)
-        self["#{name}_type"]         = Wand.wave(file.path)
-        self["#{name}_name"]         = Joint.file_name(file)
-        attachment_assignments[name] = file
-      end
+        def #{name}?
+          self.send(:#{name}_id?)
+        end
+
+        def #{name}=(file)
+          if file.nil?
+            nil_attachments << :#{name}
+          else
+            self["#{name}_id"]               = Mongo::ObjectID.new
+            self["#{name}_size"]             = File.size(file)
+            self["#{name}_type"]             = Wand.wave(file.path)
+            self["#{name}_name"]             = Joint.file_name(file)
+            assigned_attachments[:#{name}] = file
+          end
+        end
+      EOC
     end
   end
 
   module InstanceMethods
-    def attachment_assignments
-      @attachment_assignments ||= {}
-    end
-
     def grid
       @grid ||= Mongo::Grid.new(database)
     end
 
     private
+      def assigned_attachments
+        @assigned_attachments ||= {}
+      end
+
+      def nil_attachments
+        @nil_attachments ||= Set.new
+      end
+
       def save_attachments
-        attachment_assignments.each do |attachment|
+        assigned_attachments.each do |attachment|
           name, file = attachment
-          content_type = self["#{name}_type"]
-
           if file.respond_to?(:read)
-            grid.put(file.read, self["#{name}_name"], :content_type => content_type, :_id => self["#{name}_id"])
+            file.rewind if file.respond_to?(:rewind)
+            grid.put(file.read, self["#{name}_name"], {
+              :_id          => self["#{name}_id"],
+              :content_type => self["#{name}_type"],
+            })
           end
-        end
+        end.tap(&:clear)
+      end
 
-        @attachment_assignments.clear
+      def destroy_nil_attachments
+        nil_attachments.each { |name| grid.delete(self["#{name}_id"]) }.tap(&:clear)
       end
 
-      def destroy_attached_files
-        self.class.attachment_names.each do |name|
-          grid.delete(self["#{name}_id"])
-        end
+      def destroy_all_attachments
+        self.class.attachment_names.each { |name| grid.delete(self["#{name}_id"]) }
       end
   end
 
   class AttachmentProxy
     def initialize(instance, name)
@@ -92,7 +106,11 @@
     end
 
     def method_missing(method, *args, &block)
       grid_io.send(method, *args, &block)
     end
+  end
+
+  def self.file_name(file)
+    file.respond_to?(:original_filename) ? file.original_filename : File.basename(file.path)
   end
 end