refactor prefill

app/controllers/submit_form_prefill_attachments_controller.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+class SubmitFormPrefillAttachmentsController < ActionController::API
+  include ActiveStorage::SetCurrent
+
+  def create
+    submitter = Submitter.find_by!(slug: params[:submit_form_slug])
+
+    unless can_upload?(submitter)
+      return render json: { error: I18n.t('form_has_been_archived') }, status: :unprocessable_content
+    end
+
+    uuid, slug = ApplicationRecord.signed_id_verifier.verify(params[:prefill_token], purpose: :prefill_attachment)
+
+    raise ActiveRecord::RecordNotFound if slug != submitter.slug
+
+    source_attachment = ActiveStorage::Attachment.find_by!(uuid:)
+
+    attachment = submitter.attachments_attachments.find_or_create_by!(blob_id: source_attachment.blob_id)
+
+    render json: attachment.as_json(only: %i[uuid created_at], methods: %i[url filename content_type])
+  end
+
+  private
+
+  def can_upload?(submitter)
+    !submitter.declined_at? &&
+      !submitter.completed_at? &&
+      !submitter.submission.archived_at? &&
+      !submitter.submission.expired? &&
+      !submitter.submission.template&.archived_at?
+  end
+end