Add widget page support for placeholder-plain

Author: Sebastian Straub

packages/placeholder-plain/dist/getPageRef.d.ts

@@ -3,6 +3,7 @@
  *
  * @param {Buffer} pdfBuffer
  * @param {Object} info As extracted from readRef()
+ * @param {Number} [pageNumber = 0] Desired page number
  */
-export default function getPageRef(pdfBuffer: Buffer, info: any): string;
+export default function getPageRef(pdfBuffer: Buffer, info: any, pageNumber?: number): any;
 //# sourceMappingURL=getPageRef.d.ts.map

packages/placeholder-plain/dist/getPageRef.d.ts.map

@@ -4,6 +4,7 @@ Object.defineProperty(exports, "__esModule", {
   value: true
 });
 exports.default = getPageRef;
+var _utils = require("@signpdf/utils");
 var _getPagesDictionaryRef = _interopRequireDefault(require("./getPagesDictionaryRef"));
 var _findObject = _interopRequireDefault(require("./findObject"));
 function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
@@ -12,14 +13,19 @@ function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { de
  *
  * @param {Buffer} pdfBuffer
  * @param {Object} info As extracted from readRef()
+ * @param {Number} [pageNumber = 0] Desired page number
  */
-function getPageRef(pdfBuffer, info) {
+function getPageRef(pdfBuffer, info, pageNumber = 0) {
   const pagesRef = (0, _getPagesDictionaryRef.default)(info);
   const pagesDictionary = (0, _findObject.default)(pdfBuffer, info.xref, pagesRef);
   const kidsPosition = pagesDictionary.indexOf('/Kids');
   const kidsStart = pagesDictionary.indexOf('[', kidsPosition) + 1;
   const kidsEnd = pagesDictionary.indexOf(']', kidsPosition);
   const pages = pagesDictionary.slice(kidsStart, kidsEnd).toString();
-  const split = pages.trim().split(' ', 3);
-  return `${split[0]} ${split[1]} ${split[2]}`;
+  const pagesSplit = [];
+  pages.trim().split(' ').forEach((v, i) => i % 3 === 0 ? pagesSplit.push([v]) : pagesSplit[pagesSplit.length - 1].push(v));
+  if (pageNumber < 0 || pagesSplit.length <= pageNumber) {
+    throw new _utils.SignPdfError(`Failed to get reference of page "${pageNumber}".`, _utils.SignPdfError.TYPE_INPUT);
+  }
+  return pagesSplit[pageNumber].join(' ');
 }

packages/placeholder-plain/dist/getPageRef.js

@@ -1,4 +1,4 @@
-export function plainAddPlaceholder({ pdfBuffer, reason, contactInfo, name, location, signingTime, signatureLength, subFilter, widgetRect, appName, }: InputType): Buffer;
+export function plainAddPlaceholder({ pdfBuffer, reason, contactInfo, name, location, signingTime, signatureLength, subFilter, widgetRect, widgetPage, appName, }: InputType): Buffer;
 export type InputType = {
     pdfBuffer: Buffer;
     reason: string;
@@ -15,6 +15,10 @@ export type InputType = {
      * [x1, y1, x2, y2] widget rectangle
      */
     widgetRect?: number[];
+    /**
+     * Page number where the widget should be placed
+     */
+    widgetPage?: number;
     /**
      * Name of the application generating the signature
      */

packages/placeholder-plain/dist/plainAddPlaceholder.d.ts

@@ -39,6 +39,7 @@ const getAcroFormRef = slice => {
 * @property {number} [signatureLength]
 * @property {string} [subFilter] One of SUBFILTER_* from \@signpdf/utils
 * @property {number[]} [widgetRect] [x1, y1, x2, y2] widget rectangle
+* @property {number} [widgetPage] Page number where the widget should be placed
 * @property {string} [appName] Name of the application generating the signature
 */
 
@@ -64,11 +65,12 @@ const plainAddPlaceholder = ({
   signatureLength = _utils.DEFAULT_SIGNATURE_LENGTH,
   subFilter = _utils.SUBFILTER_ADOBE_PKCS7_DETACHED,
   widgetRect = [0, 0, 0, 0],
+  widgetPage = 0,
   appName = undefined
 }) => {
   let pdf = (0, _utils.removeTrailingNewLine)(pdfBuffer);
   const info = (0, _readPdf.default)(pdf);
-  const pageRef = (0, _getPageRef.default)(pdf, info);
+  const pageRef = (0, _getPageRef.default)(pdf, info, widgetPage);
   const pageIndex = (0, _getIndexFromRef.default)(info.xref, pageRef);
   const addedReferences = new Map();
   const pdfKitMock = {
@@ -109,6 +111,7 @@ const plainAddPlaceholder = ({
     signatureLength,
     subFilter,
     widgetRect,
+    widgetPage,
     appName
   });
   if (!getAcroFormRef(pdf.toString())) {

packages/placeholder-plain/dist/plainAddPlaceholder.d.ts.map

@@ -1,3 +1,4 @@
+import {SignPdfError} from '@signpdf/utils';
 import getPagesDictionaryRef from './getPagesDictionaryRef';
 import findObject from './findObject';
 
@@ -6,14 +7,19 @@ import findObject from './findObject';
  *
  * @param {Buffer} pdfBuffer
  * @param {Object} info As extracted from readRef()
+ * @param {Number} [pageNumber = 0] Desired page number
  */
-export default function getPageRef(pdfBuffer, info) {
+export default function getPageRef(pdfBuffer, info, pageNumber = 0) {
     const pagesRef = getPagesDictionaryRef(info);
     const pagesDictionary = findObject(pdfBuffer, info.xref, pagesRef);
     const kidsPosition = pagesDictionary.indexOf('/Kids');
     const kidsStart = pagesDictionary.indexOf('[', kidsPosition) + 1;
     const kidsEnd = pagesDictionary.indexOf(']', kidsPosition);
     const pages = pagesDictionary.slice(kidsStart, kidsEnd).toString();
-    const split = pages.trim().split(' ', 3);
-    return `${split[0]} ${split[1]} ${split[2]}`;
+    const pagesSplit = [];
+    pages.trim().split(' ').forEach((v, i) => (i % 3 === 0 ? pagesSplit.push([v]) : pagesSplit[pagesSplit.length - 1].push(v)));
+    if (pageNumber < 0 || pagesSplit.length <= pageNumber) {
+        throw new SignPdfError(`Failed to get reference of page "${pageNumber}".`, SignPdfError.TYPE_INPUT);
+    }
+    return pagesSplit[pageNumber].join(' ');
 }

packages/placeholder-plain/dist/plainAddPlaceholder.js

@@ -42,6 +42,7 @@ const getAcroFormRef = (slice) => {
 * @property {number} [signatureLength]
 * @property {string} [subFilter] One of SUBFILTER_* from \@signpdf/utils
 * @property {number[]} [widgetRect] [x1, y1, x2, y2] widget rectangle
+* @property {number} [widgetPage] Page number where the widget should be placed
 * @property {string} [appName] Name of the application generating the signature
 */
 
@@ -67,11 +68,12 @@ export const plainAddPlaceholder = ({
     signatureLength = DEFAULT_SIGNATURE_LENGTH,
     subFilter = SUBFILTER_ADOBE_PKCS7_DETACHED,
     widgetRect = [0, 0, 0, 0],
+    widgetPage = 0,
     appName = undefined,
 }) => {
     let pdf = removeTrailingNewLine(pdfBuffer);
     const info = readPdf(pdf);
-    const pageRef = getPageRef(pdf, info);
+    const pageRef = getPageRef(pdf, info, widgetPage);
     const pageIndex = getIndexFromRef(info.xref, pageRef);
     const addedReferences = new Map();
 
@@ -126,6 +128,7 @@ export const plainAddPlaceholder = ({
         signatureLength,
         subFilter,
         widgetRect,
+        widgetPage,
         appName,
     });