module Scrivito
#
# This module provides CMS controller actions.
# Include it in controller you want to make able to deliver +Obj+s.
#
# @api public
#
# @see Scrivito::TestRequest#for_scrivito_obj
#
# @example
#   class PageCmsController < ApplicationController
#     include Scrivito::ControllerActions
#   end
#
module ControllerActions
  extend ActiveSupport::Concern

  included do
    before_filter :require_authenticated_editor, only: [
      :show_widget,
      :widget_details,
      :page_details,
      :resource_details,
    ]

    before_filter :load_object
  end

  #
  # Default action.
  # Delivers files directly if +Obj+ is binary.
  # Otherwise the view is rendered.
  #
  # @api public
  #
  def index
    deliver_file if @obj.binary?
  end

  def show_widget
    widget = load_widget
    render text: Scrivito::WidgetTag.new(view_context, widget).render, layout: false
  end

  def widget_details
    assert_dialog_layout
    widget = load_widget
    template_path = "#{widget.obj_class_name.underscore}/details"
    render template_path, layout: 'scrivito_dialog', locals: {widget: widget}
  end

  def page_details
    assert_dialog_layout
    render @obj.details_view_path, layout: 'scrivito_dialog'
  end

  def resource_details
    assert_dialog_layout
    @scrivito_resource = editing_context.selected_workspace.objs
        .find_including_deleted(params[:resource_id])
    render text: '', layout: 'scrivito_dialog'
  end

  module ClassMethods
    #
    # This method indicates if this controller should be used automatically when an +Obj+ is
    # requested via the SDK's standard routes. It returns +true+ by default.
    #
    # Overwrite it to return +false+ if you do want your controller to be excluded from +Obj+
    # dispatching.
    #
    # @api public
    # @see Obj#controller_name
    #
    def use_for_obj_dispatch?
      true
    end
  end

  private

  def require_authenticated_editor
    head(:forbidden) unless editing_context.authenticated_editor?
  end

  def editing_context
    EditingContextMiddleware.from_request(request)
  end

  delegate :comparison, to: :editing_context

  def load_object
    CmsEnv.new(request.env).load
    loaded_obj = request.env[CmsEnv::OBJ_ENV_KEY]
    raise loaded_obj if loaded_obj.is_a?(StandardError)
    @obj = loaded_obj
  end

  def load_widget
    widget = widget_from_current_revision || widget_from_base_revision
    raise ResourceNotFound, "Widget with ID #{params[:widget_id]} not found!" unless widget
    widget
  end

  def widget_from_current_revision
    @obj.widget_from_pool(params[:widget_id])
  end

  def widget_from_base_revision
    if comparison.active? # The "diff" mode.
      @obj.in_revision(editing_context.selected_workspace.base_revision)
        .widget_from_pool(params[:widget_id])
    end
  end

  #
  # Deliver a binary +Obj+ by redirecting to its {BasicObj#binary Obj#binary}'s url.
  # Will respond with 404 if the +Obj+ has no +blob+.
  #
  # @api public
  #
  def deliver_file
    if url = @obj.binary_url
      redirect_to CmsRouting.match_protocol(url, request)
    else
      render text: 'Empty Blob', status: 404
    end
  end

  def assert_dialog_layout
    view_context.lookup_context.find('layouts/scrivito_dialog')
  rescue ActionView::MissingTemplate
    raise %{
      Missing the Scrivito dialog layout!

      Scrivito requires a special view layout in order to render the details dialog.
      Normally the install generator places it in `app/views/layouts/scrivito_dialog.html.erb`.
      If upgrading Scrivito, please re-run the install generator: `rails g scrivito:install`.
    }
  end
end

end