rootstrap/activeadmin-chat

module ActiveAdmin
  module Chat
    module Generators
      class InstallGenerator < Rails::Generators::NamedBase
        argument :name, default: ''
        class_option :conversation_model_name, type: :string, default: 'conversation'
        class_option :message_model_name, type: :string, default: 'message'
        class_option :admin_user_model_name, type: :string, default: 'admin_user'
        class_option :user_model_name, type: :string, default: 'user'

        source_root File.expand_path('templates', __dir__)

        def normalize_config
          @conversation_model_name = options['conversation_model_name'].underscore.singularize
          @message_model_name = options['message_model_name'].underscore.singularize
          @admin_user_model_name = options['admin_user_model_name'].underscore.singularize
          @user_model_name = options['user_model_name'].underscore.singularize
          @messages_per_page = 25
        end

        def copy_initializer
          template 'initializers/active_admin/chat.rb.erb',
                   'config/initializers/active_admin/chat.rb'
        end

        def create_models
          unless model_exists?(@conversation_model_name)
            Rails::Generators.invoke(
              'active_record:model', [
                @conversation_model_name,
                "#{@user_model_name.split('/').last}_id:integer:index",
                '--migration',
                '--timestamps'
              ]
            )
          end

          unless model_exists?(@message_model_name)
            Rails::Generators.invoke(
              'active_record:model', [
                @message_model_name,
                'content:string',
                'sender:references{polymorphic}',
                "#{@conversation_model_name.split('/').last}_id:integer:index",
                'created_at:datetime:index',
                'updated_at:datetime',
                '--migration',
                '--no-timestamps'
              ]
            )
          end
        end

        def inject_models_contents
          if model_exists?(@conversation_model_name)
            inject_into_class(
              model_path(@conversation_model_name),
              @conversation_model_name.classify,
              conversation_contents
            )
          end

          if model_exists?(@message_model_name)
            inject_into_class(
              model_path(@message_model_name),
              @message_model_name.classify,
              message_contents
            )
          end
        end

        def insert_chat_page
          template 'pages/chat.rb', 'app/admin/chat.rb'
        end

        private

        def conversation_contents
          buffer = <<-CONTENT
  #{add_belongs_to(@user_model_name)}
  #{add_has_many(@message_model_name)}
          CONTENT

          buffer
        end

        def message_contents
          buffer = <<-CONTENT
  #{add_belongs_to(@conversation_model_name)}
          CONTENT

          buffer
        end

        def add_belongs_to(model_name)
          if model_name.include?('/')
            "belongs_to :#{model_name.split('/').last}, class_name: '#{model_name.classify}'"
          else
            "belongs_to :#{model_name}"
          end
        end

        def add_has_many(model_name)
          relation_name = model_name.split('/').last.pluralize

          if model_name.include?('/')
            "has_many :#{relation_name}, class_name: #{model_name.classify}, dependent: :destroy"
          else
            "has_many :#{relation_name}, dependent: :destroy"
          end
        end

        def model_exists?(model_name)
          File.exist?(File.join(destination_root, model_path(model_name)))
        end

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