Update interaction.js

dctools/libraries/interaction.js

@@ -110,16 +110,37 @@ $('#copyable-link').blur(function () {
 // Check if the user already specified an expression in the URL
 $(function () {
   const expressionBase64 = trimSpaces(getQueryVariable('expression'));
-  if (expressionBase64) {
+  const expression_unicode = trimSpaces(getQueryVariable('expression'));
+  const checkValue = isBase64Encoded(expressionBase64);
+  //console.log(isBase64Encoded(expressionBase64));
+  ///if (expressionBase64) {
+  //  $('#equation-input').val(atob(expressionBase64.replace('/', '')));
+  //}
+  if(checkValue) 
     $('#equation-input').val(atob(expressionBase64.replace('/', '')));
-  }
+  else 
+    $('#equation-input').val(decodeURIComponent(expression_unicode));
+
 });
 
 // Function to trim leading and trailing spaces
 function trimSpaces(s) {
   return s.trim ? s.trim() : s.replace(/^\s\s*/, '').replace(/\s\s*$/, '');
 }
 
+function isBase64Encoded(str) {
+  // Remove white spaces from the string before checking
+  str = str.trim();
+
+  // Base64 encoded strings typically have a length that is a multiple of 4
+  // and only contain characters from the base64 character set, plus optional '=' padding
+  const base64Regex = /^[A-Za-z0-9+/]*={0,2}$/;
+
+  // Unicode-encoded strings should not match the base64 regex
+  return base64Regex.test(str);
+}
+
+
 // Function to get the value of a query variable from the URL
 function getQueryVariable(variable) {
   const query = window.location.search.substring(1);