lib/mvcli/loader.rb in mvcli-0.0.16 vs lib/mvcli/loader.rb in mvcli-0.1.0

@@ -1,11 +1,55 @@
 require "active_support/inflector/methods"
 
 module MVCLI
   class Loader
-    include ActiveSupport::Inflector
 
+    def initialize(extensions = {})
+      @extensions = Map extensions
+      @default_handler = RubyClassLoader.new
+    end
+
     def load(type, name, *args, &block)
       constantize(camelize("#{name}_#{type}")).new(*args, &block)
+    end
+
+    def exists?(path, extension_type, name)
+      pathname = handler(extension_type).to_path name, extension_type
+      path.exists? pathname
+    end
+
+    def read(path, extension_type, name, namespace = Object)
+      pathname = handler(extension_type).to_path name, extension_type
+      bytes = path.read pathname
+      handler(extension_type).define name, bytes, extension_type, namespace
+    end
+
+    private
+
+    def handler(extension_type)
+      @extensions[extension_type] || @default_handler
+    end
+
+    class RubyClassLoader
+      include ActiveSupport::Inflector
+
+      def to_path(name, extension_type)
+        "#{pluralize extension_type}/#{name}_#{extension_type}.rb"
+      end
+
+      def define(name, bytes, extension_type, namespace)
+        eval bytes, TOPLEVEL_BINDING, to_path(name, extension_type), 1
+        components = [namespace.name, classify("#{name}_#{extension_type}")]
+        components.shift if namespace == Object
+        lookup components.join('::'), to_path(name, extension_type)
+      end
+
+      private
+
+      def lookup(class_name, filename)
+        constantize class_name
+      rescue NameError
+        fail LoadError, "expected #{filename} to define #{class_name}"
+      end
     end
   end
 end