gistfile1.txt

# Render index page
class IndexFor
  DEFAULT_OPTIONS = {
    by: nil,
    pagination: :bottom, # top, bottom, both
  }.with_indifferent_access

  attr_reader :resource, :options, :block, :h

  def initialize(resource, options = {}, view_context, &block)
    @resource = resource
    @options  = with_default_options(options)
    @block    = block
    @h        = view_context
  end

  def render
    result = if collection?
      if grouped_collection?
        render_collection_groups
      else
        render_collection
      end
    else
      render_entry
    end

    h.content_tag :div, class: wrapper_html_class do
      h.concat(render_heading)
      h.concat(h.raw(result))
      h.concat(h.paginate(resource)) if collection?
    end
  end

  protected

  def with_default_options(options)
    DEFAULT_OPTIONS.merge(options)
  end

  def collection?
    resource.respond_to?(:each)
  end

  def grouped_collection?
    collection? && options[:by].to_i > 0
  end

  def render_heading
    if collection?
      h.heading_with_title
      h.heading_with_title(h.t("#{singular_class_name}.index.heading"))
    else
      h.heading_with_title(resource)
    end
  end

  def render_collection
    result = ''

    if block.nil?
      result = h.render(resource)
    else
      resource.each do |res|
        result << h.capture(res, &block)
      end
    end

    result
  end

  def render_collection_groups
    unless options[:by].to_i.even?
      raise ArgumentError, "Option `by` should be even number"
    end

    result     = ''
    html_class = "col-sm-#{12 / options[:by]}"

    resource.in_groups_of(options[:by], false).each do |group|
      row = h.content_tag :div, class: :row do
        entries = ''

        group.each do |entry|
          content = if block.nil?
            h.render(entry)
          else
            h.capture(entry, &block)
          end

          entries << h.content_tag(:div, content, class: html_class)
        end

        h.raw(entries)
      end

      result << row
    end

    result
  end

  def render_entry
    h.capture(resource, &block)
  end

  def class_name
    if collection?
      resource.klass.name.gsub('/', '_')
    else
      resource.class.name.gsub('/', '_')
    end
  end

  def plural_class_name
    class_name.underscore.pluralize.gsub('/', '_')
  end

  def singular_class_name
    class_name.underscore.singularize.gsub('/', '_')
  end

  def wrapper_html_class
    html_class = if collection?
      plural_class_name
    else
      singular_class_name
    end

    "#{html_class}-wrapper"
  end
end

module ApplicationHelper
  def index_for(resources, options = {}, &block)
    IndexFor.new(resources, options, self, &block).render
  end

  def show_for(resources, options = {}, &block)
    IndexFor.new(resources, options, self, &block).render
  end

  def item_for(resource, &block)
    content_tag_for :article, resource  do
      capture(resource, &block)
    end
  end

  def homepage?
    current_page?(root_path)
  end

  def homepage_or_inner_class
    if homepage?
      'page-home'
    else
      'page-inner'
    end
  end
end