Draft: Resolve "[Document Sealing] Implement PDF parser"

Closes #1

dist/pdfParser.js

@@ -48,13 +48,22 @@ class PDFparser {
         this.insertQrCode = (imgBytes) => __awaiter(this, void 0, void 0, function* () {
             const pdfDoc = yield PDFDocument.load(this.document);
             const img = yield pdfDoc.embedPng(imgBytes);
-            const imagePage = pdfDoc.insertPage(0);
-            imagePage.drawImage(img, {
-                x: 0,
-                y: 0,
-                width: imagePage.getWidth(),
-                height: imagePage.getHeight(),
+            // const imagePage = pdfDoc.insertPage(0);
+            const pages = pdfDoc.getPages();
+            const firstPage = pages[0];
+            const { width, height } = firstPage.getSize();
+            firstPage.drawImage(img, {
+                x: firstPage.getWidth() / 2 - img.width / 2,
+                y: firstPage.getHeight() / 2 - img.height / 2,
+                width: img.width,
+                height: img.height,
             });
+            // firstPage.drawImage(img, {
+            //   x: 0,
+            //   y: 0,
+            //   width: firstPage.getWidth(),
+            //   height: firstPage.getHeight(),
+            // });
             const pdfBytes = yield pdfDoc.save();
             return pdfBytes;
         });