RolifyCommunity/rolify

require 'rails/generators/active_record'
require 'active_support/core_ext'
require 'erb'

module ActiveRecord
  module Generators
    class RolifyGenerator < ActiveRecord::Generators::Base
      source_root File.expand_path("../templates", __FILE__)

      argument :user_cname, :type => :string, :default => "User", :banner => "User"

      def ensure_user_class_defined
        unless user_class_defined?
          prompt_missing_user
          abort
        end
      end

      def generate_model
        invoke "active_record:model", [ name ], :migration => false
      end

      def inject_role_class
        if args[1]=="engine"
          if args[2]=="devise"
            require 'devise'
            require "#{ENGINE_ROOT}/config/initializers/devise.rb"
            require "#{ENGINE_ROOT}/app/models/#{user_cname.downcase}.rb"
          else
            require "#{ENGINE_ROOT}/app/models/#{user_cname.downcase}.rb"
          end
        end

        inject_into_class(model_path, class_name, model_content)
      end

      def copy_rolify_migration
        migration_template "migration.rb", "db/migrate/rolify_create_#{table_name}.rb", migration_version: migration_version
      end

      private

      def join_table
        user_class.table_name + "_" + table_name
      end

      def user_reference
        user_cname.demodulize.underscore
      end

      def role_reference
        class_name.demodulize.underscore
      end

      def model_path
        File.join("app", "models", "#{file_path}.rb")
      end

      def model_content
        ERB.new(File.read(File.join(__dir__, 'templates/model.rb'))).result(binding)
      end

      def user_class
        user_cname.constantize
      end

      def user_class_defined?
        user_class
        true
      rescue NameError => ex
        if ex.missing_name == user_cname
          false
        else
          raise ex
        end
      end

      def prompt_missing_user
        puts <<MSG
Rolify expected a model named #{user_cname} to be defined but could not find one.
Please ensure that this model exists and is not mis-spelled and re-run the generator.
MSG
      end

      def versioned_migrations?
        Rails::VERSION::MAJOR >= 5
      end

      def migration_version
        if versioned_migrations?
          "[#{Rails::VERSION::MAJOR}.#{Rails::VERSION::MINOR}]"
        end
      end

    end
  end
end