Adding language selector

code_editor.py

@@ -1,3 +1,5 @@
+# code_editor.py
+
 import streamlit as st
 import streamlit_ace as st_ace
 import os
@@ -5,6 +7,7 @@ import time, psutil
 from pathlib import Path
 from utils import execute_code
 
+# Default code snippets
 DEFAULT_SNIPPETS = {
     "Python": '''# default code\na = int(input())\nb = int(input())\nprint("Sum:", a + b)''',
     "C": '''// default code\n#include <stdio.h>\nint main() {\n    int a, b;\n    scanf("%d %d", &a, &b);\n    printf("Sum: %d\\n", a + b);\n    return 0;\n}''',
@@ -14,6 +17,7 @@ DEFAULT_SNIPPETS = {
     "C#": '''// default code\nusing System;\npublic class Program {\n    public static void Main(string[] args) {\n        int a = Convert.ToInt32(Console.ReadLine());\n        int b = Convert.ToInt32(Console.ReadLine());\n        Console.WriteLine("Sum: " + (a + b));\n    }\n}'''
 }
 
+# Extension-to-language mapping
 EXT_LANG_MAP = {
     ".py": "Python",
     ".cpp": "C++",
@@ -23,7 +27,15 @@ EXT_LANG_MAP = {
     ".cs": "C#"
 }
 
-def render_code_editor(selected_lang, ace_theme, editor_key):
+def render_code_editor(ace_theme):
+    # ── Language Selector ──────────────────────────────
+    lang_list = list(DEFAULT_SNIPPETS.keys())
+    default_lang = st.session_state.get("language", "Python")
+    selected_lang = st.selectbox("Language", lang_list, index=lang_list.index(default_lang))
+    st.session_state.language = selected_lang
+    editor_key = f"editor_{selected_lang}"
+
+    # ── File Upload ──────────────────────────────
     uploaded_file = st.file_uploader("📤 Upload file", type=["py", "cpp", "c", "java", "js", "cs", "txt"])
 
     if uploaded_file:
@@ -37,6 +49,7 @@ def render_code_editor(selected_lang, ace_theme, editor_key):
             prev_name = st.session_state.get("uploaded_file_name")
             prev_content = st.session_state.get("uploaded_file_content")
 
+            # Only react to new uploads
             if content != prev_content or filename != prev_name:
                 st.session_state.uploaded_file_name = filename
                 st.session_state.uploaded_file_content = content
@@ -55,20 +68,20 @@ def render_code_editor(selected_lang, ace_theme, editor_key):
                     st.error("❌ Unsupported file format.")
                     return
 
-    # Handle default fallback (only if no upload or no valid code set)
-    previous_lang = st.session_state.get("prev_language")
+    # ── Fallback Default Code ──────────────────────────────
+    prev_lang = st.session_state.get("prev_language")
     default_code = DEFAULT_SNIPPETS[selected_lang]
 
     if (
         st.session_state.get("code") is None
         or st.session_state.code.strip() == ""
-        or selected_lang != previous_lang
-        or st.session_state.code.strip() == DEFAULT_SNIPPETS.get(previous_lang, "")
+        or selected_lang != prev_lang
+        or st.session_state.code.strip() == DEFAULT_SNIPPETS.get(prev_lang, "")
     ):
         st.session_state.code = default_code
         st.session_state.prev_language = selected_lang
 
-    # ── ACE Editor ──────────────────────────────
+    # ── ACE Code Editor ──────────────────────────────
     code = st_ace.st_ace(
         value=st.session_state.code,
         placeholder=f"Start typing your {selected_lang} code…",
@@ -86,7 +99,7 @@ def render_code_editor(selected_lang, ace_theme, editor_key):
     if code != st.session_state.code:
         st.session_state.code = code
 
-    # ── Input ──────────────────────────────
+    # ── Stdin Input ──────────────────────────────
     user_input = st.text_area(
         "📥 Input (stdin)",
         value=st.session_state.stdin,
@@ -122,7 +135,7 @@ def render_code_editor(selected_lang, ace_theme, editor_key):
         st.markdown(f"⏱️ **Execution Time:** `{exec_time:.4f}s`")
         st.markdown(f"💾 **Memory Used:** `{mem_used:.2f} KB`")
 
-    # ── Download ──────────────────────────────
+    # ── Download Code ──────────────────────────────
     if st.session_state.code:
         lang_ext = {
             "Python": "py", "C": "c", "C++": "cpp", "Java": "java",