trestle_generator.rb

class TrestleSandbox
  include ActionView::Helpers::ActiveRecordHelper

  attr_accessor :form_action, :singular_name, :suffix, :model_instance

  def sandbox_binding
    binding
  end

  def default_input_block
    Proc.new { |record, column| "<p><label for=\"#{record}_#{column.name}\">#{column.human_name}</label><br/>\n#{input(record, column.name)}</p>\n" }
  end
end

class ActionView::Helpers::InstanceTag
  def to_input_field_tag(field_type, options={})
    field_meth = "#{field_type}_field"
    "<%= #{field_meth} '#{@object_name}', '#{@method_name}' #{options.empty? ? '' : ', '+options.inspect} %>"
  end

  def to_text_area_tag(options = {})
    "<%= text_area '#{@object_name}', '#{@method_name}' #{options.empty? ? '' : ', '+ options.inspect} %>"
  end

  def to_date_select_tag(options = {})
    "<%= date_select '#{@object_name}', '#{@method_name}' #{options.empty? ? '' : ', '+ options.inspect} %>"
  end

  def to_datetime_select_tag(options = {})
    "<%= datetime_select '#{@object_name}', '#{@method_name}' #{options.empty? ? '' : ', '+ options.inspect} %>"
  end
end

class TrestleGenerator < Rails::Generator::NamedBase
  attr_reader  :controller_name,
               :controller_class_path,
               :controller_file_path,
               :controller_class_nesting,
               :controller_class_nesting_depth,
               :controller_class_name,
               :controller_singular_name,
               :controller_plural_name
  alias_method :controller_file_name,  :controller_singular_name
  alias_method :controller_table_name, :controller_plural_name

  def initialize(runtime_args, runtime_options = {})
    super

    # Take controller name from the next argument. Default to the pluralized model name.
    @controller_name = args.shift
    @controller_name ||= ActiveRecord::Base.pluralize_table_names ? @name.pluralize : @name

    base_name, @controller_class_path, @controller_file_path, @controller_class_nesting, @controller_class_nesting_depth = extract_modules(@controller_name)
    @controller_class_name_without_nesting, @controller_singular_name, @controller_plural_name = inflect_names(base_name)

    if @controller_class_nesting.empty?
      @controller_class_name = @controller_class_name_without_nesting
    else
      @controller_class_name = "#{@controller_class_nesting}::#{@controller_class_name_without_nesting}"
    end
  end

  def manifest
    record do |m|
      # Check for class naming collisions.
      m.class_collisions controller_class_path, "#{controller_class_name}Controller", "#{controller_class_name}ControllerTest", "#{controller_class_name}Helper"

      # Controller, helper, views, test, and config directories.
      m.directory File.join('app/controllers', controller_class_path)
      m.directory File.join('app/helpers', controller_class_path)
      m.directory File.join('app/views', controller_class_path, controller_file_name)
      m.directory File.join('test/functional', controller_class_path)
      m.directory File.join('config', controller_class_path)

      # Depend on model generator but skip if the model exists.
      m.dependency 'model', [singular_name], :collision => :skip, :skip_migration => true

      # Trestle forms.
      m.complex_template "form.rhtml",
        File.join('app/views',
                  controller_class_path,
                  controller_file_name,
                  "_form.rhtml"),
        :insert => 'form_trestle.rhtml',
        :sandbox => lambda { create_sandbox },
        :begin_mark => 'form',
        :end_mark => 'eoform',
        :mark_id => singular_name

      # Trestle views.
      trestle_views.each do |action|
        m.template "view_#{action}.rhtml",
                   File.join('app/views',
                             controller_class_path,
                             controller_file_name,
                             "#{action}.rhtml"),
                   :assigns => { :action => action }
      end

      # Controller class, functional test, helper, and views.
      m.template 'controller.rb',
                  File.join('app/controllers',
                            controller_class_path,
                            "#{controller_file_name}_controller.rb")

      m.template 'functional_test.rb',
                  File.join('test/functional',
                            controller_class_path,
                            "#{controller_file_name}_controller_test.rb")

      m.template 'helper.rb',
                  File.join('app/helpers',
                            controller_class_path,
                            "#{controller_file_name}_helper.rb")

      # Layout and stylesheet.
      m.template 'layout.rhtml',
                 File.join('app/views/layouts',
                           controller_class_path,
                           "#{controller_file_name}.rhtml")
      m.template 'style.css', 'public/stylesheets/trestle.css'


      # Non-trestle views.
      nontrestle_actions.each do |action|
        path = File.join('app/views',
                          controller_class_path,
                          controller_file_name,
                          "#{action}.rhtml")
        m.template "controller:view.rhtml", path,
                   :assigns => { :action => action, :path => path}
      end

      # Routes.
      m.template 'routes.rb', 'config/routes.rb'
    end
  end


  protected

  # Override with your own usage banner.
  def banner
    "Usage: #{$0} trestle ModelName [ControllerName] [action, ...]"
  end

  def trestle_views
    %w(edit list new show)
  end

  def trestle_actions
    %w(destroy edit list new show)
  end

  def model_name 
    class_name.demodulize
  end

  def nontrestle_actions
    args - trestle_actions
  end

  def suffix
    "_#{singular_name}" if options[:suffix]
  end

  def create_sandbox
    sandbox = TrestleSandbox.new
    sandbox.singular_name = singular_name
    begin
      sandbox.model_instance = model_instance
      sandbox.instance_variable_set("@#{singular_name}", sandbox.model_instance)
    rescue ActiveRecord::StatementInvalid => e
      logger.error "Before updating trestle from new DB schema, try creating a table for your model (#{class_name})"
      raise SystemExit
    end
    sandbox.suffix = suffix
    sandbox
  end

  def model_instance
    base = class_nesting.split('::').inject(Object) do |base, nested|
      break base.const_get(nested) if base.const_defined?(nested)
      base.const_set(nested, Module.new)
    end
    unless base.const_defined?(@class_name_without_nesting)
      base.const_set(@class_name_without_nesting, Class.new(ActiveRecord::Base))
    end
    class_name.constantize.new
  end
end