module Scrivito

class ClientConfig < Struct.new(:obj, :editing_context, :lookup_context, :resource, :return_to)
  def initialize(obj, editing_context, lookup_context, options = {})
    super(obj, editing_context, lookup_context, *options.values_at(:resource, :return_to))
  end

  def to_json
    config = {}
    config[:current_page]        = current_page_config
    config[:editing_context]     = editing_context_config
    config[:i18n]                = i18n_config
    config[:resource_dialog]     = resource_dialog_config
    config[:user]                = user_config
    config[:user_permissions]    = user_permissions_config
    config[:is_development_mode] = Rails.env.development?
    config.to_json
  end

  private

  def editing_context_config
    {
      display_mode: editing_context.display_mode,

      selected_workspace: {
        id: selected_workspace.id,
        title: selected_workspace.title,
        outdated: selected_workspace.outdated?
      },

      visible_workspace: {
        id: visible_workspace.id,
        title: visible_workspace.title
      }
    }
  end

  def i18n_config
    {locale: Scrivito::Configuration.ui_locale || I18n.locale}
  end

  def current_page_config
    if obj
      {
        id: obj.id,
        obj_class_name: obj.obj_class_name,
        has_children: obj.children.any?,
        has_conflict: obj.has_conflict?,
        has_details_view: obj_has_details_view?,
        modification: modification(obj),
        restriction_messages: editor.restriction_messages_for(obj),
      }
    else
      {}
    end
  end

  def obj_has_details_view?
    lookup_context.find(obj.details_view_path).present?
  rescue ActionView::MissingTemplate
    false
  end

  def resource_dialog_config
    if resource
      {
        obj: Configuration.obj_formats.fetch('_default').call(resource, editor),
        return_to: return_to,
      }
    else
      {}
    end
  end

  def user_permissions_config
    {
      create_workspace: editor.can?(:create, :workspace),
      publish_workspace: editor.can?(:publish, selected_workspace),
    }
  end

  def user_config
    {
      current: {
        id: editor.id
      }
    }
  end

  def modification(obj_or_resource)
    comparison = editing_context.comparison
    if comparison.active?
      comparison.modification(obj_or_resource)
    else
      obj_or_resource.modification
    end
  end

  def editor
    editing_context.editor
  end

  def selected_workspace
    editing_context.selected_workspace
  end

  def visible_workspace
    editing_context.visible_workspace
  end
end

end