Hfrhyu

I have created a portal which export map and then print. I just wanted to add template or draw layout in canvas for that pdf as shown in the picture below.

Here is my code:

//print map
var dims = 
 a0: [1189, 841],
 a1: [841, 594],
 a2: [594, 420],
 a3: [420, 297],
 a4: [297, 210],
 a5: [210, 148]
;

var exportElement = document.getElementById("export-pdf");
exportElement.addEventListener(
 "click",
 function(e) 
 exportElement.disabled = true;
 document.body.style.cursor = "progress";

 var format = document.getElementById("format").value;
 var resolution = document.getElementById("resolution").value;
 var buttonLabelElement = document.getElementById("button-label");
 var label = buttonLabelElement.innerText;
 var scale = 4000;

 var mapView = map.getView();
 var mapProjection = mapView.getProjection();
 var mapResolutionAtEquator = mapView.getResolution();
 var viewCenter = mapView.getCenter();
 var mapPointResolution = ol.proj.getPointResolution(
 mapProjection,
 mapResolutionAtEquator,
 viewCenter
 );

 var dim = dims[format];
 var width = Math.round((dim[0] * resolution) / 25.4);
 var height = Math.round((dim[1] * resolution) / 25.4);
 var size = map.getSize();
 var extent = map.getView().calculateExtent(size);

 var mapView = map.getView();
 var currZoom = mapView.getZoom();
 var mapProjection = mapView.getProjection();
 var mapResolutionAtEquator = mapView.getResolution();
 var viewCenter = mapView.getCenter();
 var mapResolutionAtEquator = mapView.getResolution();
 var mapPointResolution = ol.proj.getPointResolution(
 mapProjection,
 mapResolutionAtEquator,
 viewCenter
 );
 var mapResolutionFactor = mapResolutionAtEquator / mapPointResolution;
 var pdf_name = dist + "_" + tahsil + "_" + village + ".pdf";

 map.once("rendercomplete", function(event) 
 var canvas = event.context.canvas;
 showText(event.context, "left-top", dist, tahsil, village);
 drawLegend(event.context, "right-bottom");
 drawNorthArrow(event.context, "right-top");

 WriteScaletoCanvas(event);
 var data = canvas.toDataURL("image/jpeg");
 var pdf = new jsPDF("landscape", undefined, format);
 pdf.addImage(data, "JPEG", 0, 0, dim[0], dim[1]);
 pdf.save(pdf_name);
 map.setSize(size);
 // map.getView().fit(extent, size);
 mapView.setZoom(currZoom);
 exportElement.disabled = false;
 document.body.style.cursor = "auto";
 );

 var printPointResolution = (scale * 25.4) / (resolution * 1000); // edit1: corrected
 var printResolutionAtEquator = mapResolutionFactor * printPointResolution;
 var printZoom = mapView.getZoomForResolution(printResolutionAtEquator);

 map.setSize([width, height]);
 // mapView.fit(extent, (map.getSize()));
 mapView.setZoom(printZoom);
 ,
 false
);

For example:

How to create this layout pdf?