module ImportExport
  private
  def export_data
    initialize_job(true)
  end

  def import_data(uploader, owner)
    return render_bad_import_request('Please upload a file to import.') if uploaded_file_blank?

    begin
      data = read_import_file(uploader, owner)
    rescue Exception
      render_bad_import_request('Wrong file type or content.')
    else
      initialize_job(false, data)
    end
  end

  def uploaded_file_blank?
    params[:upload].blank? || params[:upload][:datafile].blank?
  end

  def render_bad_import_request(errors)
    respond_to { |format| format.json { render json: { 'upload.datafile' => [errors] }, status: :bad_request } }
  end

  # Initialize a background task to handle the actual import / export of data
  def initialize_job(export_job, data = nil)
    @job_id = export_job ? start_export_job : start_import_job(data)

    handle_import_export_response
  end

  def handle_import_export_response
    @result = { job_type: 'instant',
                job_id: @job_id,
                status_url: report_runner_status_path(job_id: @job_id) }

    respond_to { |format| format.json { render json: @result } }
  end
end