Fix missing annotation parent in using the one from the Fields entry

Fixes #15096.

src/core/annotation.js

@@ -112,6 +112,7 @@ class AnnotationFactory {
    * @params {Object} annotationGlobals
    * @param {Object} idFactory
    * @param {boolean} [collectFields]
+   * @param {Object} [orphanFields]
    * @param {Object} [pageRef]
    * @returns {Promise} A promise that is resolved with an {Annotation}
    *   instance.
@@ -122,6 +123,7 @@ class AnnotationFactory {
     annotationGlobals,
     idFactory,
     collectFields,
+    orphanFields,
     pageRef
   ) {
     const pageIndex = collectFields
@@ -134,6 +136,7 @@ class AnnotationFactory {
       annotationGlobals,
       idFactory,
       collectFields,
+      orphanFields,
       pageIndex,
       pageRef,
     ]);
@@ -148,6 +151,7 @@ class AnnotationFactory {
     annotationGlobals,
     idFactory,
     collectFields = false,
+    orphanFields = null,
     pageIndex = null,
     pageRef = null
   ) {
@@ -173,6 +177,7 @@ class AnnotationFactory {
       id,
       annotationGlobals,
       collectFields,
+      orphanFields,
       needAppearances:
         !collectFields && acroForm.get("NeedAppearances") === true,
       pageIndex,
@@ -623,7 +628,11 @@ function getTransformMatrix(rect, bbox, matrix) {
 
 class Annotation {
   constructor(params) {
-    const { dict, xref, annotationGlobals } = params;
+    const { dict, xref, annotationGlobals, ref, orphanFields } = params;
+    const parentRef = orphanFields?.get(ref);
+    if (parentRef) {
+      dict.set("Parent", parentRef);
+    }
 
     this.setTitle(dict.get("T"));
     this.setContents(dict.get("Contents"));
@@ -3172,6 +3181,11 @@ class ButtonWidgetAnnotation extends WidgetAnnotation {
       }
     }
 
+    if (!this.parent) {
+      // If there is no parent then we must set the value in the field.
+      dict.set("V", name);
+    }
+
     dict.set("AS", name);
     dict.set("M", `D:${getModificationDate()}`);
     if (flags !== undefined) {

src/core/document.js

@@ -787,12 +787,16 @@ class Page {
         if (annots.length === 0) {
           return annots;
         }
-        const annotationGlobals =
-          await this.pdfManager.ensureDoc("annotationGlobals");
+
+        const [annotationGlobals, fieldObjects] = await Promise.all([
+          this.pdfManager.ensureDoc("annotationGlobals"),
+          this.pdfManager.ensureDoc("fieldObjects"),
+        ]);
         if (!annotationGlobals) {
           return [];
         }
 
+        const orphanFields = fieldObjects?.orphanFields;
         const annotationPromises = [];
         for (const annotationRef of annots) {
           annotationPromises.push(
@@ -802,6 +806,7 @@ class Page {
               annotationGlobals,
               this._localIdFactory,
               /* collectFields */ false,
+              orphanFields,
               this.ref
             ).catch(function (reason) {
               warn(`_parsedAnnotations: "${reason}".`);
@@ -1776,10 +1781,12 @@ class PDFDocument {
 
   async #collectFieldObjects(
     name,
+    parentRef,
     fieldRef,
     promises,
     annotationGlobals,
-    visitedRefs
+    visitedRefs,
+    orphanFields
   ) {
     const { xref } = this;
 
@@ -1797,7 +1804,7 @@ class PDFDocument {
     } else {
       let obj = field;
       while (true) {
-        obj = obj.getRaw("Parent");
+        obj = obj.getRaw("Parent") || parentRef;
         if (obj instanceof Ref) {
           if (visitedRefs.has(obj)) {
             break;
@@ -1815,6 +1822,15 @@ class PDFDocument {
       }
     }
 
+    if (
+      parentRef &&
+      !field.has("Parent") &&
+      isName(field.get("Subtype"), "Widget")
+    ) {
+      // We've a parent from the Fields array, but the field hasn't.
+      orphanFields.put(fieldRef, parentRef);
+    }
+
     if (!promises.has(name)) {
       promises.set(name, []);
     }
@@ -1825,6 +1841,7 @@ class PDFDocument {
         annotationGlobals,
         /* idFactory = */ null,
         /* collectFields */ true,
+        orphanFields,
         /* pageRef */ null
       )
         .then(annotation => annotation?.getFieldObject())
@@ -1842,10 +1859,12 @@ class PDFDocument {
       for (const kid of kids) {
         await this.#collectFieldObjects(
           name,
+          fieldRef,
           kid,
           promises,
           annotationGlobals,
-          visitedRefs
+          visitedRefs,
+          orphanFields
         );
       }
     }
@@ -1867,13 +1886,16 @@ class PDFDocument {
       const visitedRefs = new RefSet();
       const allFields = Object.create(null);
       const fieldPromises = new Map();
+      const orphanFields = new RefSetCache();
       for (const fieldRef of await acroForm.getAsync("Fields")) {
         await this.#collectFieldObjects(
           "",
+          null,
           fieldRef,
           fieldPromises,
           annotationGlobals,
-          visitedRefs
+          visitedRefs,
+          orphanFields
         );
       }
 
@@ -1890,7 +1912,7 @@ class PDFDocument {
       }
 
       await Promise.all(allPromises);
-      return allFields;
+      return { allFields, orphanFields };
     });
 
     return shadow(this, "fieldObjects", promise);
@@ -1914,7 +1936,7 @@ class PDFDocument {
       return true;
     }
     if (fieldObjects) {
-      return Object.values(fieldObjects).some(fieldObject =>
+      return Object.values(fieldObjects.allFields).some(fieldObject =>
         fieldObject.some(object => object.actions !== null)
       );
     }

src/core/worker.js

@@ -522,7 +522,9 @@ class WorkerMessageHandler {
     });
 
     handler.on("GetFieldObjects", function (data) {
-      return pdfManager.ensureDoc("fieldObjects");
+      return pdfManager
+        .ensureDoc("fieldObjects")
+        .then(fieldObjects => fieldObjects?.allFields || null);
     });
 
     handler.on("HasJSActions", function (data) {