integrated html2canvas and jsPDF to generate PDFs

src/components/App/App.js

@@ -1,23 +1,31 @@
-import React, { useEffect, useContext, Suspense } from 'react';
+import React, { useRef, useEffect, useContext, Suspense } from 'react';
 import { useTranslation } from 'react-i18next';
 
 import AppContext from '../../context/AppContext';
+import PageContext from '../../context/PageContext';
+
 import LeftSidebar from '../LeftSidebar/LeftSidebar';
 import RightSidebar from '../RightSidebar/RightSidebar';
 
 import templates from '../../templates';
 
 const App = () => {
+  const pageRef = useRef(null);
   const { i18n } = useTranslation();
+
   const context = useContext(AppContext);
   const { state, dispatch } = context;
   const { theme, settings } = state;
 
+  const pageContext = useContext(PageContext);
+  const { setPageElement } = pageContext;
+
   useEffect(() => {
+    setPageElement(pageRef);
     i18n.changeLanguage(settings.language);
     const storedState = JSON.parse(localStorage.getItem('state'));
     dispatch({ type: 'import_data', payload: storedState });
-  }, [dispatch, i18n, settings.language]);
+  }, [dispatch, setPageElement, i18n, settings.language]);
 
   return (
     <Suspense fallback="Loading...">
@@ -25,11 +33,7 @@ const App = () => {
         <LeftSidebar />
 
         <div className="z-0 h-screen col-span-3 flex justify-center items-center overflow-scroll">
-          <div
-            id="page"
-            className="animated fadeIn my-auto shadow-2xl"
-            style={{ animationDelay: '500ms' }}
-          >
+          <div id="page" ref={pageRef} className="my-auto shadow-2xl">
             {templates.find(x => theme.layout.toLowerCase() === x.key).component()}
           </div>
         </div>

src/components/RightSidebar/RightSidebar.js

@@ -43,7 +43,7 @@ const RightSidebar = () => {
       name: t('about.title'),
     },
   ];
-  const [currentTab, setCurrentTab] = useState(tabs[0].key);
+  const [currentTab, setCurrentTab] = useState(tabs[3].key);
 
   const onChange = (key, value) => {
     dispatch({

src/components/RightSidebar/tabs/Actions.js

@@ -1,9 +1,16 @@
+/* eslint-disable new-cap */
 /* eslint-disable jsx-a11y/anchor-has-content */
 /* eslint-disable jsx-a11y/anchor-is-valid */
-import React, { useRef } from 'react';
+import React, { useRef, useContext } from 'react';
 import { useTranslation, Trans } from 'react-i18next';
+import html2canvas from 'html2canvas';
+import * as jsPDF from 'jspdf';
+
+import PageContext from '../../../context/PageContext';
 
 const ActionsTab = ({ data, theme, dispatch }) => {
+  const pageContext = useContext(PageContext);
+  const { pageElement } = pageContext;
   const { t } = useTranslation('rightSidebar');
   const fileInputRef = useRef(null);
 
@@ -17,6 +24,35 @@ const ActionsTab = ({ data, theme, dispatch }) => {
     fr.readAsText(event.target.files[0]);
   };
 
+  const printAsPdf = () => {
+    pageElement.current.style.maxHeight = 'fit-content';
+    pageElement.current.style.overflow = 'visible';
+    html2canvas(pageElement.current, {
+      useCORS: true,
+      allowTaint: true,
+    }).then(canvas => {
+      pageElement.current.style.maxHeight = '29.7cm';
+      pageElement.current.style.overflow = 'scroll';
+      const image = canvas.toDataURL('image/jpeg', 1.0);
+      const doc = new jsPDF('p', 'px', 'a4');
+      const pageWidth = doc.internal.pageSize.getWidth();
+      const pageHeight = doc.internal.pageSize.getHeight();
+
+      const widthRatio = pageWidth / canvas.width;
+      const heightRatio = pageHeight / canvas.height;
+      const ratio = widthRatio > heightRatio ? heightRatio : widthRatio;
+
+      const canvasWidth = canvas.width * ratio;
+      const canvasHeight = canvas.height * ratio;
+
+      const marginX = (pageWidth - canvasWidth) / 2;
+      const marginY = (pageHeight - canvasHeight) / 2;
+
+      doc.addImage(image, 'JPEG', marginX, marginY, canvasWidth, canvasHeight);
+      doc.output('dataurlnewwindow');
+    });
+  };
+
   const exportToJson = () => {
     const backupObj = { data, theme };
     const dataStr = `data:text/json;charset=utf-8,${encodeURIComponent(JSON.stringify(backupObj))}`;
@@ -90,7 +126,7 @@ const ActionsTab = ({ data, theme, dispatch }) => {
 
         <button
           type="button"
-          onClick={() => window.print()}
+          onClick={printAsPdf}
           className="mt-4 bg-blue-600 hover:bg-blue-700 text-white text-sm font-medium py-2 px-5 rounded"
         >
           <div className="flex justify-center items-center">