fix(core): update

ts/smartpdf.classes.smartpdf.ts

@@ -3,7 +3,7 @@ import * as paths from './smartpdf.paths';
 import { Server } from 'http';
 import { PdfCandidate } from './smartpdf.classes.pdfcandidate';
 
-declare const document;
+declare const document: any;
 
 import * as interfaces from './interfaces';
 
@@ -19,7 +19,7 @@ export class SmartPdf {
     this._readyDeferred = new plugins.smartpromise.Deferred();
   }
 
-  async start(headlessBrowserArg?) {
+  async start(headlessBrowserArg?: plugins.smartpuppeteer.puppeteer.Browser) {
     // lets set the external browser in case one is provided
     this.headlessBrowser = headlessBrowserArg;
     // setup puppeteer
@@ -80,7 +80,7 @@ export class SmartPdf {
     }
 
     const pdfBuffer = await page.pdf({
-      format: 'A4',
+      format: 'a4',
       printBackground: true,
       displayHeaderFooter: false,
       preferCSSPageSize: true,
@@ -108,7 +108,7 @@ export class SmartPdf {
       };
     });
     const pdfBuffer = await page.pdf({
-      format: 'A4',
+      format: 'a4',
       height: documentWidth,
       width: documentWidth,
       printBackground: true,
@@ -135,7 +135,7 @@ export class SmartPdf {
       };
     });
     const pdfBuffer = await page.pdf({
-      format: 'A4',
+      format: 'a4',
       height: documentWidth,
       width: documentWidth,
       printBackground: true,
@@ -149,4 +149,12 @@ export class SmartPdf {
       buffer: pdfBuffer,
     };
   }
+
+  public async mergePdfBuffers(pdfBuffers: Buffer[]): Promise<Buffer> {
+    const merger = new plugins.pdfMerger();
+    for (const buffer of pdfBuffers) {
+      merger.add(buffer);
+    }
+    return merger.saveAsBuffer();
+  }
 }