module ExpressTemplates
  module Components
    module Capabilities

      module Resourceful
        def namespace
          @config[:namespace] || infer_namespace
        end

        def path_prefix
          @config[:path_prefix] || infer_path_prefix
        end

        def resource_class
          resource_class = @config[:resource_class] || _namespaced_resource_class
          resource_class.constantize
        end

        private

        def _namespaced_resource_class
          if namespace
            "#{namespace}/#{resource_name}".classify
          else
            resource_name.classify
          end
        end

        def infer_namespace
          expander = @args.last
          if expander.try(:template)
            path_parts = expander.template.virtual_path.split('/')

            case
            when path_parts.size == 4
              path_parts.first
            when path_parts.size == 3
              mod = path_parts.first.classify.constantize
              if mod.const_defined?(:Engine)
                path_parts.first
              else
                nil
              end
            else
              nil
            end
          else
            nil
          end
        end

        def infer_path_prefix
          expander = @args.last
          if expander.try(:template)
            path_parts = expander.template.virtual_path.split('/')

            case
            when path_parts.size == 4
              path_parts[1]
            when path_parts.size == 3
              mod = path_parts.first.classify.constantize
              if mod.const_defined?(:Engine)
                nil
              else
                path_parts.first
              end
            else
              nil
            end
          else
            nil
          end
        end

        # TODO: this can now be inferred from the template.virtual_path
        # if not supplied...
        def resource_name
          @config[:id].to_s.singularize
        end

        def collection_member_name
          resource_name
        end

        def collection_name
          collection_member_name.pluralize
        end

        def collection_var
          "@#{collection_name}".to_sym
        end

        def collection
          @config[:collection] || collection_var
        end

        def collection_path
          if @config[:collection_path]
            @config[:collection_path]
          else
            "#{collection_name_with_prefix}_path"
          end
        end

        def collection_name_with_prefix
          if path_prefix
            "#{path_prefix}_#{collection_name}"
          else
            collection_name
          end
        end

        def resource_path(ivar=false)
          if @config[:resource_path]
            @config[:resource_path]
          else
            "#{resource_name_with_path_prefix}_path(#{ivar ? '@' : ''}#{resource_name})"
          end
        end

        def resource_name_with_path_prefix
          if path_prefix
            "#{path_prefix}_#{resource_name}"
          else
            resource_name
          end
        end

        def attributes
          resource_class.columns
        end
      end
    end
  end
end