fix ace editor change listener removal

sumorobot.js

@@ -7,7 +7,9 @@ var remoteControl = false;
 var robotServer = "iot.koodur.com";
 
 /* ace editor object */
-var pythonEditor = null;
+var codingEditor = null;
+/* ace editor change callback */
+var codingCallback = null;
 
 /* the sumorobot code */
 var sumocode = "";
@@ -17,8 +19,8 @@ var sumorobot = null;
 var workspace = null;
 /* the sumorobot state */
 var sumostart = false;
-/* disable / enable Python code */
-var pythonEnabled = false;
+/* disable / enable coding mode */
+var codingEnabled = false;
 
 /* control_if block id */
 var controlBlockId = "";
@@ -105,23 +107,23 @@ function setLocalStorageItem(item, value) {
 window.onload = function() {
     $("#robot-id").val(getLocalStorageItem("sumorobot.robotId"));
     /* load ace editor */
-    pythonEditor = ace.edit("blocklyCode");
+    codingEditor = ace.edit("blocklyCode");
     /* set the style */
-    pythonEditor.setTheme("ace/theme/textmate");
-    pythonEditor.session.setMode("ace/mode/python");
-    pythonEditor.session.setTabSize(2);
-    pythonEditor.setReadOnly(true);
+    codingEditor.setTheme("ace/theme/textmate");
+    codingEditor.session.setMode("ace/mode/python");
+    codingEditor.session.setTabSize(2);
+    codingEditor.setReadOnly(true);
     /* disable scrolling warning */
-    pythonEditor.$blockScrolling = Infinity;
+    codingEditor.$blockScrolling = Infinity;
     /* enable autocomplete */
     ace.require("ace/ext/language_tools");
-    pythonEditor.setOptions({
+    codingEditor.setOptions({
         enableSnippets: true,
         enableLiveAutocompletion: true,
         enableBasicAutocompletion: true
     });
     /* add autocomplete keywords */
-    pythonEditor.completers.push({
+    codingEditor.completers.push({
     getCompletions: function(editor, session, pos, prefix, callback) {
             callback(null, [
                 {value: "STOP", score: 1000, meta: "sumorobot"},
@@ -361,8 +363,8 @@ window.onload = function() {
         sumocode = Blockly.Python.workspaceToCode(workspace);
 
         /* show the code in the ace editor, filter out block IDs */
-        pythonEditor.setValue("\n" + sumocode.replace(/[,]?[ ]?"(.*?)"/g, ""));
-        pythonEditor.clearSelection();
+        codingEditor.setValue("\n" + sumocode.replace(/[,]?[ ]?"(.*?)"/g, ""));
+        codingEditor.clearSelection();
 
         /* save the code to the local storage */
         var xml = Blockly.Xml.workspaceToDom(workspace);
@@ -420,28 +422,29 @@ window.onload = function() {
             case 80: // p
                 $("#blocklyDiv").toggle();
                 $("#blocklyArea").toggle();
-                /* resize the Python code editor */
-                pythonEditor.resize();
+                /* resize the code editor */
+                codingEditor.resize();
                 /* disable / enable ace editor */
-                pythonEditor.setReadOnly(pythonEnabled);
-                /* toggle python enabled */
-                pythonEnabled = !pythonEnabled;
-                if (pythonEnabled) {
-                    /* get the saved Python code from local storage or set empty */
-                    pythonEditor.setValue(getLocalStorageItem("sumorobot.python") || "");
-                    /* add an input listener for the code editor */
-                    pythonEditor.on("change", function() {
-                        setLocalStorageItem("sumorobot.python", pythonEditor.getValue())
-                    });
-                    pythonEditor.clearSelection();
-                    pythonEditor.focus();
+                codingEditor.setReadOnly(codingEnabled);
+                /* toggle coding enabled */
+                codingEnabled = !codingEnabled;
+                if (codingEnabled) {
+                    /* get the saved code from local storage or set empty */
+                    codingEditor.setValue(getLocalStorageItem("sumorobot.code") || "");
+                    /* add an change listener for the code editor */
+                    codingCallback = function() {
+                        setLocalStorageItem("sumorobot.code", codingEditor.getValue())
+                    };
+                    codingEditor.on("change", codingCallback);
+                    codingEditor.clearSelection();
+                    codingEditor.focus();
                 } else {
-                    /* remove input listener from the code editor */
-                    pythonEditor.session.removeAllListeners("change");
-                    /* fire CHANGE event in Blockly workspace to change the Python code */
+                    /* remove change listener from the coding editor */
+                    codingEditor.off("change", codingCallback);
+                    /* fire CHANGE event in Blockly workspace to change the code */
                     var event = {type: Blockly.Events.CHANGE};
                     workspace.fireChangeListener(event);
-                    pythonEditor.blur();
+                    codingEditor.blur();
                 }
                 break;
             case 82: // r
@@ -477,10 +480,10 @@ window.onload = function() {
     /* start button listener */
     $(".btn-start").click(function() {
         sumostart = true;
-        /* if we are in Python mode */
-        if (pythonEnabled) {
+        /* if we are in coding mode */
+        if (codingEnabled) {
             /* send the code from the textarea to the SumoRobot */
-            sumorobot.send("start:" + pythonEditor.getValue());
+            sumorobot.send("start:" + codingEditor.getValue());
         /* otherwise when we are in Blockly mode */
         } else {
             /* send the code from the blocks to the SumoRobot */