module Scrivito
  class ObjsController < WebserviceController
    around_action :require_selected_workspace_write_authorization, only: [
      :destroy,
      :restore,
      :restore_widget,
      :revert,
      :revert_widget,
    ]

    before_filter :require_identical_selected_and_visible_workspace, only: [
      :page_class_selection,
      :widget_class_selection,
    ]

    def show
      in_selected_workspace { render }
    end

    def widget
      in_selected_workspace { render }
    end

    def details
      assert_dialog_layout
      render current_obj.details_view_path, layout: 'scrivito_dialog', formats: :html
    end

    def destroy
      in_selected_workspace do
        parent = current_obj.parent
        @redirect_to = parent ? scrivito_path(parent) : "/"
        current_obj.destroy
      end
    end

    def revert
      in_selected_workspace { current_obj.revert }
      render_empty_json
    end

    def revert_widget
      in_selected_workspace { current_widget.revert }
      render_empty_json
    end

    def restore
      in_selected_workspace { Obj.restore(params[:id]) }
      render_empty_json
    end

    def restore_widget
      in_selected_workspace { current_obj.restore_widget(params[:widget_id]) }
      render_empty_json
    end

    def binary_no_cache
      in_selected_workspace do
        binary = current_obj[params[:attribute_name]]
        @no_cache_url = binary.no_cache_url
      end
    end

    def transfer_modifications
      in_selected_workspace do
        begin
          obj = Obj.find_including_deleted(params[:id])
          workspace = Workspace.find(params[:workspace_id])
          authorize_workspace_access(:write, workspace) do
            obj.transfer_modifications_to(workspace)
          end
        rescue TransferModificationsModifiedError
          @error_reason = :modified
        rescue TransferModificationsConflictError
          @error_reason = :conflict
        end
      end
    end

    def page_class_selection
      @page_class_markup = valid_page_classes.map do |page_class_name|
        build_selection_option(page_class_name)
      end
    end

    def widget_class_selection
      load_obj

      @widgets_classes = valid_widget_classes.map do |widget_class_name|
        build_selection_option(widget_class_name)
      end
    end

    def search
      in_selected_workspace do
        @query = MultiJson.decode(params[:query]).with_indifferent_access
        @enumerator = ObjSearchBuilder.new(@query).build

        if params[:query_action] == 'size'
          return render action: 'search/size'
        end

        unless @formatter = fetch_formatter(@query[:format])
          return render action: 'search/missing_formatter', status: :not_found
        end

        if facet_params = params[:facet]
          attribute, options = MultiJson.decode(facet_params).values_at('attribute', 'options')
          @facets = @enumerator.facet(attribute, options || {})
          return render action: 'search/facet'
        end

        @batch = @enumerator.fetch_batch(params[:continuation])
        render :search
      end
    end

    private

    def require_identical_selected_and_visible_workspace
      if selected_workspace != editing_context.visible_workspace
        raise ScrivitoError, 'selected and visible workspace are not identical'
      end
    end

    def require_selected_workspace_write_authorization(&block)
      authorize_workspace_access(:write, selected_workspace, &block)
    end

    def in_selected_workspace(&block)
      selected_workspace.as_current(&block)
    end

    def selected_workspace
      editing_context.selected_workspace
    end

    def current_obj
      @obj || load_obj
    end
    helper_method :current_obj

    def load_obj
      @obj = Obj.find(params[:id])
    end

    def current_widget
      @widget || load_widget
    end
    helper_method :current_widget

    def load_widget
      raise ScrivitoError, 'no widget_id param specified' if params[:widget_id].blank?
      unless @widget = current_obj.widget_from_pool(params[:widget_id])
        raise ResourceNotFound, "widget with ID '#{params[:widget_id]}' not found"
      end
      @widget
    end

    def fetch_formatter(name)
      name ? Configuration.obj_formats[name] : proc { |obj, _| obj.id }
    end

    def build_selection_option(class_name)
      template_path = "#{class_name.underscore}/thumbnail"
      markup = begin
        render_to_string(template_path, layout: false, formats: :html)
      rescue ActionView::MissingTemplate
        render_to_string('scrivito/fallback_thumbnail', layout: false, formats: :html,
            locals: {class_name: class_name, template_path: template_path})
      end
      {name: class_name, markup: markup}
    end

    def valid_page_classes
      without_hidden_classes(page_classes_from_obj).map(&:to_s)
    end

    def page_classes_from_obj
      Obj.valid_page_ruby_classes_beneath(params[:parent_path])
    end

    def valid_widget_classes
      widget_classes = current_widget_or_obj.valid_widget_ruby_classes_for(params[:field_name])

      without_hidden_classes(widget_classes).map(&:to_s)
    end

    def without_hidden_classes(obj_types)
      obj_types.reject(&:hide_from_editor?)
    end

    def current_widget_or_obj
      widget_id = params[:widget_id]
      (widget_id && current_obj.widgets[widget_id]) || current_obj
    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