module Scrivito
  class ObjClassController < WebserviceController
    def defaults
      obj_class_name = params.fetch(:obj_class_name)
      obj_class = fetch_obj_class(obj_class_name)
      if obj_class
        @defaults = compute_defaults_for(obj_class)
      else
        raise ResourceNotFound, %{The obj class "#{obj_class_name}" is not available.}
      end
    end

    def thumbnails
      model_classes = [*Scrivito.models.objs, *Scrivito.models.widgets]
      @thumbnails = model_classes.each_with_object({}) do |model_class, hash|
        hash[model_class.name] = build_selection_option(model_class.name)
      end
    end

    private

    def compute_defaults_for(obj_class)
      if obj_class.ancestors.include?(BasicObj)
        compute_obj_defaults_for(obj_class)
      else
        compute_widget_defaults_for(obj_class)
      end
    end

    def compute_obj_defaults_for(obj_class)
      attributes = params.fetch(:attributes, {}).merge(_obj_class: obj_class.name)
      attributes = attributes.to_unsafe_h
      parsed_attrs = obj_params_parser.parse(attributes)
      base_defaults = obj_class.build_attributes_with_defaults(
        parsed_attrs, scrivito_user: scrivito_user)
      computed_nested_attributes(base_defaults, obj_class)
    end

    def compute_widget_defaults_for(widget_class)
      base_defaults = widget_class.build_attributes_with_defaults(
        { _obj_class: widget_class.name }, scrivito_user: scrivito_user)
      computed_nested_attributes(base_defaults, widget_class)
    end

    def computed_nested_attributes(defaults, obj_class)
      widget_attributes = {}
      other_attributes = {}

      defaults.each do |name, value|
        next if value.nil?

        attribute_type = obj_class.attribute_definitions[name].try(:type)
        if attribute_type == 'widgetlist'
          widgets = value.map do |new_widget|
            computed_nested_attributes(new_widget.attributes_to_be_saved, new_widget.class)
          end

          widget_attributes[name] = ['widgetlist', widgets]
        elsif attribute_type != 'binary'
          other_attributes[name] = value
        end
      end

      other_attributes = serialize(other_attributes, obj_class)

      widget_attributes.merge(other_attributes).merge(_obj_class: obj_class.name)
    end

    def serialize(attributes, obj_class)
      serializer = AttributeSerializer.new(obj_class)

      serializer.serialize(attributes, obj_class.attribute_definitions)
    end

    def fetch_obj_class(obj_class_name)
      compute_type(Widget, obj_class_name) || compute_type(Obj, obj_class_name)
    end

    def compute_type(base_class, obj_class_name)
      base_class.type_computer.compute_type_without_fallback(obj_class_name)
    rescue ObjClassNotFound
      nil
    end

    def obj_params_parser
      ObjCreateParamsParser.new(request.host, request.port)
    end

    def build_selection_option(class_name)
      template_path = "#{class_name.underscore}/thumbnail"

      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
    end
  end
end