add function to copy a whiteboard from another one

README.md

@@ -108,6 +108,7 @@ Call your site with GET parameters to change the WhiteboardID or the Username
 - username => The name which will be shown to others while drawing
 - title => Change the name of the Browser Tab
 - randomid => if set to true, a random whiteboardId will be generated if not given aswell
+- copyfromwid => set this to a whiteboardId you want a copy from. Only copies the content if the current whiteboard is empty.
 
 ## Configuration
 

src/js/main.js

@@ -36,6 +36,7 @@ if (urlParams.get("whiteboardid") !== whiteboardId) {
 
 const myUsername = urlParams.get("username") || "unknown" + (Math.random() + "").substring(2, 6);
 const accessToken = urlParams.get("accesstoken") || "";
+const copyfromwid = urlParams.get("copyfromwid") || "";
 
 // Custom Html Title
 const title = urlParams.get("title");
@@ -170,7 +171,17 @@ function initWhiteboard() {
         // request whiteboard from server
         $.get(subdir + "/api/loadwhiteboard", { wid: whiteboardId, at: accessToken }).done(
             function (data) {
+                console.log(data);
                 whiteboard.loadData(data);
+                if (copyfromwid && data.length == 0) {
+                    //Copy from witheboard if current is empty and get parameter is given
+                    $.get(subdir + "/api/loadwhiteboard", {
+                        wid: copyfromwid,
+                        at: accessToken,
+                    }).done(function (data) {
+                        whiteboard.loadData(data);
+                    });
+                }
             }
         );