module Camunda
  module Generators
    # Creates a skeleton Java Spring Boot app, which also contains the minimal files to run unit tests on a BPMN file.
    # This can be used to start a Camunda instance with a REST api. This can also be deployed to PCF by generating a
    # Spring Boot jar and pushing it.
    class SpringBootGenerator < Rails::Generators::Base
      source_root File.expand_path('templates', __dir__)
      class_option :bpmn_folder_name, type: :string, default: 'bpmn'
      class_option :java_app_folder_name, type: :string, default: 'java_app'
      class_option :resources_folder_name, type: :string, default: 'resources'

      # Links resources to the java app resources folder
      def link_resources_folder
        create_link resources_path, File.join(java_app_folder_name, 'src/main/resources/')
      end

      # Copies all spring boot files into a rails application and provides a Camunda engine for testing.
      def copy_java_app_files
        copy_file 'pom.xml', File.join(java_app_path, 'pom.xml')
        copy_file 'camunda.cfg.xml', File.join(java_app_path, 'src/test/resources/camunda.cfg.xml')
        copy_file 'logback.xml', File.join(java_app_path, 'src/main/resources/logback.xml')
        copy_file 'application.properties', File.join(java_app_path, 'src/main/resources/application.properties')
        copy_file 'Camunda.java', File.join(java_app_path, 'src/main/java/camunda/Camunda.java')
      end

      # Copies a sample bpmn file to help demonstrate the usage for camunda-workflow
      def copy_sample_bpmn
        copy_file 'sample.bpmn', File.join(resources_path, 'sample.bpmn')
        copy_file 'ProcessScenarioTest.java', File.join(java_app_path, 'src/test/java/unittest/ProcessScenarioTest.java')
      end

      # Add spring boot files to .gitignore
      def add_to_ignores
        ignores = %w[.gitignore]
        ignores << '.cfignore' if File.exist?('.cfignore')
        ignores.each do |file|
          append_to_file file do
            "\n# BPMN Java app\n#{File.join(java_app_path, 'target')}\n"
          end
        end
      end

      private

      def bpmn_folder_name
        options['bpmn_folder_name']
      end

      def java_app_folder_name
        options['java_app_folder_name']
      end

      def resources_folder_name
        options['resources_folder_name']
      end

      def resources_path
        File.join(bpmn_folder_name, resources_folder_name)
      end

      def java_app_path
        File.join(bpmn_folder_name, java_app_folder_name)
      end
    end
  end
end