# encoding: utf-8
require 'fedux_org_stdlib/require_files'
require_library %w(find active_support/core_ext/object/blank active_support/core_ext/string/inflections)

require 'fedux_org_stdlib/models/filesystem_based_model'

module FeduxOrgStdlib
  module Models
    # model for import action
    module ClassBasedModel
      def self.included(base)
        base.extend ClassMethods
      end

      # Class methods
      module ClassMethods
        def require_path(name)
          path = File.join(library_name.underscore, model_name.pluralize.underscore, name.to_s)
          FeduxOrgStdlib.logger.debug(self) { "Path to instances of model \"#{name}\": #{path}" }

          path
        end

        def exception_for_model
          "#{library_name}::Exceptions::Invalid#{model_name}".constantize
        rescue
          raise FeduxOrgStdlib::Models::Exceptions::ExceptionNeedsToBeImplemented, "Exception \"#{library_name}::Exceptions::Invalid#{model_name}\" does not exist."
        end

        def check_klass(klass, *methods)
          fail exception_for_model, "A valid \"#{model_name}\"-class needs to respond to \"#{ methods.flatten.join(', ') }\"." unless methods.flatten.all? { |m| klass.new.respond_to? m }
        end

        def build_class_constant(name)
          "#{library_name}::#{model_name.pluralize}::#{name.to_s.camelcase}".constantize
        rescue
          raise exception_for_model, "Class \"#{library_name}::#{model_name.pluralize}::#{name.to_s.camelcase}\" cannot be found in file \"#{require_path(name)}\"."
        end

        def check_method
          fail FeduxOrgStdlib::Models::Exceptions::MethodNeedsToBeImplemented, "Method \"check_method\" does not exist."
        end

        def suffix
          '.rb'
        end

        def load_from_filesystem
          files = find_files

          FeduxOrgStdlib.logger.debug(self) { "Files found at path \"#{path_to_instances}\": #{ files.join(', ') }" }

          fail FeduxOrgStdlib::Models::Exceptions::NoImplementationsForModelFound, "You might need to store files at \"#{File.dirname(path_to_instances)}\" to make the library work." if files.blank?

          files.each do |f|
            instance_name = name(f)

            require require_path(instance_name)

            instance_klass = build_class_constant(instance_name)
            check_klass(instance_klass, check_method)
            create(instance_name, instance_klass.new)
          end
        end
      end
    end
  end
end