Feature / modify PDF with PDF-LIB in print.js

	Insert page-break after content for A4 page (example in practice.js)

src/practice.js

+import $ from 'jquery'
+
+const practice = () => {
+    const v = $('div.fade');
+    // const v = $(':eq(0)'); // za root element
+    const va = $('div.fade').children().toArray(); // gledamo div-fade kao root
+    let i = 1, temp = 0;
+    const divRootElement = document.createElement('div');
+    divRootElement.className = 'hello';
+    const divElementPageBreak = document.createElement('div');
+    divElementPageBreak.style.pageBreakBefore = "always";
+    va.forEach(element => {
+        // 59.338582677165356 is sum of default top and bottom print margins
+        // 842 is height in pixels for A4 format
+        const razlika = element.clientHeight + temp - (i * 842 - 59.338582677165356);
+        if (razlika < 0) {
+            temp += element.clientHeight;
+            divRootElement.append(element);
+        }
+        else if (razlika === 0) {
+            i++;
+            temp = 0;
+            divRootElement.append(divElementPageBreak);
+        }
+        else {
+            if (element.hasChildNodes && element.childNodes.length === 1) {
+                const node = element.childNodes[0];
+                if (node.hasChildNodes && node.childNodes.length === 1) {
+                    const subNode = node.childNodes[0];
+                    if (subNode.hasChildNodes) {
+                        const nodes = subNode.childNodes;
+                        for (let j = 0; j < nodes.length; j++) {
+                            const razlikaNodes = nodes[j].clientHeight + temp - (i * 842 - 59.338582677165356);
+                            if (razlikaNodes < 0) {
+                                temp += nodes[j].clientHeight;
+                            }
+                            else if (razlikaNodes === 0) {
+                                i++;
+                                temp = 0;
+                                divRootElement.append(nodes[j]);
+                            }
+                            else {
+                                if (nodes[j].hasChildNodes && nodes[j].childNodes.length > 1) {
+                                    const subNodes = nodes[j].childNodes;
+                                    for (let k = 0; k < subNodes.length; k++) {
+                                        const razlikaSubNodes = subNodes[k].clientHeight + temp - (i * 842 - 59.338582677165356);
+                                        if (razlikaSubNodes < 0) {
+                                            temp += subNodes[k].clientHeight;
+                                            divRootElement.append(subNodes[k]);
+                                        }
+                                        else {
+                                            i++;
+                                            temp = 0;
+                                            divRootElement.append(divElementPageBreak);
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            else if (element.hasChildNodes && element.childNodes.length > 1) {
+                const nodes = element.childNodes;
+                for (let i = 0; i < nodes.length; i++) {
+                    if (nodes[i].clientHeight + temp < (i * 842 - 59.338582677165356)) {
+                        temp += nodes[i].clientHeight;
+                        divElement.append(nodes[i]);
+                    }
+                    else {
+                        i++;
+                        temp = 0;
+
+                    }
+                }
+
+            }
+        }
+
+    });
+    $('div.fade').empty();
+    $('div.fade').append(divRootElement);
+    // $('root').append(divRootElement);
+}
+
+export default practice;

src/transformations/header-transformations/header-every-page-transformation.css

       z-index: 9999;
       left:0;
       top: 0;
-      margin-bottom: 300px;
     }
     table { page-break-after:auto }
     tr    { page-break-inside:avoid; page-break-after:auto }

src/transformations/layout-table-transformation/landscape-transformation.css

 @media print  
 { 
+    table{
+        display: block;
+    }
+    
+    /* demo */
+    .demo {
+        height: 100vh;
+        position: relative;
+      }
+    
+      .demo::after {
+        content: attr(title);
+        position: absolute;
+        left: 0;
+        top: 0;
+        padding: .25em .5em;
+        background-color: rgba(255, 255, 255, .8);
+      }
     .table-landscape
     {
-        transform: rotate(90deg);
+        max-width: 100vh;
+        max-height: 100vw;
+        transform: translatex(calc(50vw - 50%)) translatey(calc(50vh - 50%)) rotate(90deg);
+        /* transform: rotate(90deg); */
+        /* break-before: always; */
+        /* page-break-before: always; */
+        page-break-before: auto;
     }
+    .demo { page-break-before:always }
+    /* .demo table { page-break-inside:avoid; page-break-after:auto } */
+    .demo table { page-break-inside: always; }
+    
 }

src/transformations/print.js

+  const url = ('https://localhost:7285/api/PDFGenerator/http%3A%2F%2Flocalhost%3A3000%2F%23%2Fdashboard');
+        
+        async function modifyPdf(existingPdfBytes) {
+            // const url = 'https://pdf-lib.js.org/assets/with_update_sections.pdf'
+            // const existingPdfBytes = await fetch(url).then(res => res.arrayBuffer())
+          
+            const pdfDoc = await PDFDocument.load(existingPdfBytes)
+            
+            const helveticaFont = await pdfDoc.embedFont(StandardFonts.Helvetica)
+          
+            const pages = pdfDoc.getPages()
+            const firstPage = pages[0]
+            const { width, height } = firstPage.getSize()
+            firstPage.drawText('This text was added with JavaScript!', {
+              x: 5,
+              y: height / 2 + 300,
+              size: 50,
+              font: helveticaFont,
+              color: rgb(0.95, 0.1, 0.1),
+              rotate: degrees(-45),
+            })
+          
+            const pdfBytes = await pdfDoc.save()
+            console.log(pdfBytes);
+          }
+
+        //   modifyPdf();
+        let headers = new Headers();
+        headers.append('Content-Type', 'application/pdf');
+        
+        fetch(url, {
+            method: 'GET',
+            headers: headers
+        })
+            .then(async res => ({
+                filename: "donwload.pdf",
+                blob: await res.blob()
+            }))
+            .then(resObj => {
+                // It is necessary to create a new blob object with mime-type explicitly set for all browsers except Chrome, but it works for Chrome too.
+                const newBlob = new Blob([resObj.blob], { type: 'application/pdf' });
+                const bytes = new Uint8Array(newBlob);
+                //console.log(bytes);
+                modifyPdf(bytes);
+                // MS Edge and IE don't allow using a blob object directly as link href, instead it is necessary to use msSaveOrOpenBlob
+                if (window.navigator && window.navigator.msSaveOrOpenBlob) {
+                    window.navigator.msSaveOrOpenBlob(newBlob);
+                } else {
+                    // For other browsers: create a link pointing to the ObjectURL containing the blob.
+                    const objUrl = window.URL.createObjectURL(newBlob);
+        
+                    let link = document.createElement('a');
+                    link.href = objUrl;
+                    link.download = resObj.filename;
+                    link.click();
+        
+                    // For Firefox it is necessary to delay revoking the ObjectURL.
+                    setTimeout(() => { window.URL.revokeObjectURL(objUrl); }, 250);
+                }
+            })
+            .catch((error) => {
+                console.log('DOWNLOAD ERROR', error);
+            });