fix: rewrite form flattening handler

Previously we used the form flattening method from PDF-Lib
but unfortunately when it encountered orphaned form items
or other PDF oddities it would throw an error.

Because of this certain documents would fail to seal and
be stuck in a pending state with no recourse available.
This change rewrites the form flattening handler to be
more lenient when coming across the unknown opting to skip
items it can't handle rather than abort.

apps/web/src/app/(dashboard)/admin/documents/[id]/admin-actions.tsx

@@ -2,7 +2,8 @@
 
 import Link from 'next/link';
 
-import { type Document, DocumentStatus } from '@documenso/prisma/client';
+import type { Recipient } from '@documenso/prisma/client';
+import { type Document, SigningStatus } from '@documenso/prisma/client';
 import { trpc } from '@documenso/trpc/react';
 import { cn } from '@documenso/ui/lib/utils';
 import { Button } from '@documenso/ui/primitives/button';
@@ -17,9 +18,10 @@ import { useToast } from '@documenso/ui/primitives/use-toast';
 export type AdminActionsProps = {
   className?: string;
   document: Document;
+  recipients: Recipient[];
 };
 
-export const AdminActions = ({ className, document }: AdminActionsProps) => {
+export const AdminActions = ({ className, document, recipients }: AdminActionsProps) => {
   const { toast } = useToast();
 
   const { mutate: resealDocument, isLoading: isResealDocumentLoading } =
@@ -47,7 +49,9 @@ export const AdminActions = ({ className, document }: AdminActionsProps) => {
             <Button
               variant="outline"
               loading={isResealDocumentLoading}
-              disabled={document.status !== DocumentStatus.COMPLETED}
+              disabled={recipients.some(
+                (recipient) => recipient.signingStatus !== SigningStatus.SIGNED,
+              )}
               onClick={() => resealDocument({ id: document.id })}
             >
               Reseal document

apps/web/src/app/(dashboard)/admin/documents/[id]/page.tsx

@@ -53,7 +53,7 @@ export default async function AdminDocumentDetailsPage({ params }: AdminDocument
 
       <h2 className="text-lg font-semibold">Admin Actions</h2>
 
-      <AdminActions className="mt-2" document={document} />
+      <AdminActions className="mt-2" document={document} recipients={document.Recipient} />
 
       <hr className="my-4" />
       <h2 className="text-lg font-semibold">Recipients</h2>

packages/lib/server-only/document/seal-document.ts

@@ -17,6 +17,7 @@ import { getFile } from '../../universal/upload/get-file';
 import { putPdfFile } from '../../universal/upload/put-file';
 import { getCertificatePdf } from '../htmltopdf/get-certificate-pdf';
 import { flattenAnnotations } from '../pdf/flatten-annotations';
+import { flattenForm } from '../pdf/flatten-form';
 import { insertFieldInPDF } from '../pdf/insert-field-in-pdf';
 import { normalizeSignatureAppearances } from '../pdf/normalize-signature-appearances';
 import { triggerWebhook } from '../webhooks/trigger/trigger-webhook';
@@ -101,8 +102,11 @@ export const sealDocument = async ({
 
   // Normalize and flatten layers that could cause issues with the signature
   normalizeSignatureAppearances(doc);
-  doc.getForm().flatten();
+  console.log('normalized');
+  flattenForm(doc);
+  console.log('flattened');
   flattenAnnotations(doc);
+  console.log('annotations');
 
   if (certificate) {
     const certificatePages = await doc.copyPages(certificate, certificate.getPageIndices());

packages/lib/server-only/pdf/flatten-form.ts

@@ -0,0 +1,112 @@
+import type { PDFField, PDFWidgetAnnotation } from 'pdf-lib';
+import { PDFCheckBox, PDFRadioGroup, PDFRef } from 'pdf-lib';
+import {
+  PDFDict,
+  type PDFDocument,
+  PDFName,
+  drawObject,
+  popGraphicsState,
+  pushGraphicsState,
+  rotateInPlace,
+  translate,
+} from 'pdf-lib';
+
+export const flattenForm = (document: PDFDocument) => {
+  const form = document.getForm();
+
+  form.updateFieldAppearances();
+
+  for (const field of form.getFields()) {
+    for (const widget of field.acroField.getWidgets()) {
+      flattenWidget(document, field, widget);
+    }
+
+    try {
+      form.removeField(field);
+    } catch (error) {
+      console.error(error);
+    }
+  }
+};
+
+const getPageForWidget = (document: PDFDocument, widget: PDFWidgetAnnotation) => {
+  const pageRef = widget.P();
+
+  let page = document.getPages().find((page) => page.ref === pageRef);
+
+  if (!page) {
+    const widgetRef = document.context.getObjectRef(widget.dict);
+
+    if (!widgetRef) {
+      return null;
+    }
+
+    page = document.findPageForAnnotationRef(widgetRef);
+
+    if (!page) {
+      return null;
+    }
+  }
+
+  return page;
+};
+
+const getAppearanceRefForWidget = (field: PDFField, widget: PDFWidgetAnnotation) => {
+  try {
+    const normalAppearance = widget.getNormalAppearance();
+    let normalAppearanceRef: PDFRef | null = null;
+
+    if (normalAppearance instanceof PDFRef) {
+      normalAppearanceRef = normalAppearance;
+    }
+
+    if (
+      normalAppearance instanceof PDFDict &&
+      (field instanceof PDFCheckBox || field instanceof PDFRadioGroup)
+    ) {
+      const value = field.acroField.getValue();
+      const ref = normalAppearance.get(value) ?? normalAppearance.get(PDFName.of('Off'));
+
+      if (ref instanceof PDFRef) {
+        normalAppearanceRef = ref;
+      }
+    }
+
+    return normalAppearanceRef;
+  } catch (error) {
+    console.error(error);
+
+    return null;
+  }
+};
+
+const flattenWidget = (document: PDFDocument, field: PDFField, widget: PDFWidgetAnnotation) => {
+  try {
+    const page = getPageForWidget(document, widget);
+
+    if (!page) {
+      return;
+    }
+
+    const appearanceRef = getAppearanceRefForWidget(field, widget);
+
+    if (!appearanceRef) {
+      return;
+    }
+
+    const xObjectKey = page.node.newXObject('FlatWidget', appearanceRef);
+
+    const rectangle = widget.getRectangle();
+    const operators = [
+      pushGraphicsState(),
+      translate(rectangle.x, rectangle.y),
+      ...rotateInPlace({ ...rectangle, rotation: 0 }),
+      drawObject(xObjectKey),
+      popGraphicsState(),
+    ].filter((op) => !!op);
+
+    page.pushOperators(...operators);
+  } catch (error) {
+    console.error(error);
+  }
+};

packages/trpc/server/admin-router/router.ts

@@ -1,6 +1,7 @@
 import { TRPCError } from '@trpc/server';
 
 import { findDocuments } from '@documenso/lib/server-only/admin/get-all-documents';
+import { getEntireDocument } from '@documenso/lib/server-only/admin/get-entire-document';
 import { updateRecipient } from '@documenso/lib/server-only/admin/update-recipient';
 import { updateUser } from '@documenso/lib/server-only/admin/update-user';
 import { sealDocument } from '@documenso/lib/server-only/document/seal-document';
@@ -10,6 +11,7 @@ import { upsertSiteSetting } from '@documenso/lib/server-only/site-settings/upse
 import { deleteUser } from '@documenso/lib/server-only/user/delete-user';
 import { getUserById } from '@documenso/lib/server-only/user/get-user-by-id';
 import { extractNextApiRequestMetadata } from '@documenso/lib/universal/extract-request-metadata';
+import { DocumentStatus } from '@documenso/prisma/client';
 
 import { adminProcedure, router } from '../trpc';
 import {
@@ -100,7 +102,11 @@ export const adminRouter = router({
       const { id } = input;
 
       try {
-        return await sealDocument({ documentId: id, isResealing: true });
+        const document = await getEntireDocument({ id });
+
+        const isResealing = document.status === DocumentStatus.COMPLETED;
+
+        return await sealDocument({ documentId: id, isResealing });
       } catch (err) {
         console.error('resealDocument error', err);