error handling

Author: varun-s22

README.md

@@ -1,7 +1,18 @@
 # Leetcode Code Format Extension
 
-This is a Chrome Extension, which formats the code typed by the user on [Leetcode](https://www.leetcode.com/) platform. 
+This is a Chrome Extension, which formats the code typed by the user on [Leetcode](https://www.leetcode.com/) platform.
 
 Currently it supports only Python.
 
 API for formatting python code is hosted via serverless functions on Vercel.
+
+## Build
+
+Currently it is not available on Chrome Web Store. To unpack it locally, follow these steps:
+
+- Get the directory/repo on your local machine(git clone works).
+- Open [Chrome Extensions](chrome://extensions/)
+- Switch the developer mode to be "on".
+- Click on Load Unpacked button, and select the directory.
+
+Your extension has been successfully loaded.

script.js

@@ -21,18 +21,40 @@ const mutationObserver = new MutationObserver(() => {
   getCodeMirror();
   let btnDiv = document.querySelector("button[data-cy='submit-code-btn']");
   if (btnDiv === undefined || btnDiv === null) {
-    // div not found
+    // buttons div not rendered yet
     return;
   }
   let parent = btnDiv.parentElement;
-  if (!isBtnPresent) {
-    parent.prepend(btn);
-    let btnDivSpan = btnDiv.childNodes[0];
-    span.className = btnDivSpan.className;
-    btn.style.padding = "1.2em";
-    btn.className = btnDiv.className;
-    btn.append(span);
-    isBtnPresent = true;
+  let languageDiv = document.querySelector(
+    ".ant-select-selection-selected-value"
+  );
+  if (languageDiv === undefined || languageDiv === null) {
+    // language div not rendered yet
+    return;
+  }
+  if (
+    languageDiv.innerText === "Python" ||
+    languageDiv.innerText === "Python3"
+  ) {
+    if (!isBtnPresent) {
+      parent.prepend(btn);
+      let btnDivSpan = btnDiv.childNodes[0];
+      span.className = btnDivSpan.className;
+      btn.style.padding = "1.2em";
+      btn.className = btnDiv.className;
+      btn.append(span);
+      isBtnPresent = true;
+    }
+  } else {
+    if (isBtnPresent) {
+      let childList = parent.childNodes;
+      if (childList === undefined || childList === null) {
+        // children not loaded
+        return;
+      }
+      childList[0].remove();
+      isBtnPresent = false;
+    }
   }
 });
 mutationObserver.observe(document, {