Update app.py

app.py

@@ -2,74 +2,90 @@ import streamlit as st
 import google.generativeai as genai
 import os
 
-# ---------- UI ----------
+# -------------------------------------------------
+# 1️⃣  UI – page setup
+# -------------------------------------------------
 st.set_page_config(page_title="Python Code Reviewer 🤖", layout="centered")
 st.title("🐍 Python Code Reviewer 🤖")
-st.markdown("### Paste your code and a short prompt – the AI will review it for you!")
+st.markdown(
+    "### Paste your code and a short prompt – the AI will review it for you!"
+)
 
-# 1️⃣ API key input (optional)
+# -------------------------------------------------
+# 2️⃣  Input fields
+# -------------------------------------------------
+# API key (optional – fallback to hard‑coded key)
 api_key_input = st.text_input(
     "🔑 Google API Key (optional – leave blank to use the built‑in key)",
     type="password",
-    help="If you have your own Gemini API key, enter it here. Otherwise the app will fall back to the default key."
+    help="Enter your own Gemini API key if you have one. Otherwise the app uses the default key."
 )
 
-# 2️⃣ System prompt (optional)
-sys_prompt = st.text_input(
+# System prompt (optional – fallback to env var or default)
+sys_prompt_input = st.text_input(
     "🗒️ System Prompt (optional)",
     placeholder="e.g., 'You are a friendly Python code reviewer.'",
-    help="Custom instructions for the model. If left empty, the environment variable USER_PROMPT is used."
+    help="Custom instructions for the model. If left empty, the USER_PROMPT env var is used."
 )
 
-# 3️⃣ Code box
+# Code to be reviewed
 code_box = st.text_area(
     "💻 Your Python code:",
     height=200,
     placeholder="# Paste your Python code here"
 )
 
-# 4️⃣ Action prompt box
+# What the model should do with the code
 prompt_box = st.text_area(
     "📝 What should the AI do with this code?",
     height=80,
     placeholder="e.g., 'Find bugs and suggest improvements.'"
 )
 
-# ---------- Logic ----------
+# -------------------------------------------------
+# 3️⃣  Main logic – run when button pressed
+# -------------------------------------------------
 if st.button("🚀 Review"):
-    # Validate that there is code to review
+    # ---- Validate input ----
     if not code_box.strip():
         st.warning("⚠️ Please paste some Python code.")
         st.stop()
 
-    # Choose API key: user‑provided > hard‑coded fallback
+    # ---- Choose API key ----
+    # User‑provided key > hard‑coded fallback
     api_key = api_key_input.strip() or "AIzaSyBiAW2GQLid0HGe9Vs_ReKwkwsSVNegNzs"
     genai.configure(api_key=api_key)
 
-    # Choose system instruction: user input > env var > none
+    # ---- Choose system instruction ----
+    # User input > env var > generic default
     system_instruction = (
-        sys_prompt.strip()
+        sys_prompt_input.strip()
         or os.getenv("USER_PROMPT")
         or "You are a helpful Python code reviewer."
     )
 
-    # Initialise model with the chosen system instruction
+    # ---- Initialise model ----
     model = genai.GenerativeModel(
         model_name="models/gemini-2.5-flash",
         system_instruction=system_instruction,
     )
 
-    # Build the full user message
-    user_message = f"Code:\n```python\n{code\_box}\n```\n\nTask: {prompt_box or 'Review the code.'}"
+    # ---- Build the user message ----
+    user_message = (
+        f"Code:\n```python\n{code\_box}\n```\n\n"
+        f"Task: {prompt_box or 'Review the code.'}"
+    )
 
-    # Call Gemini
+    # ---- Call Gemini ----
     with st.spinner("Analyzing your code... 🧐"):
         response = model.generate_content(user_message)
 
-    # Show result
+    # ---- Show result ----
     st.markdown("### 🤖 Response")
     st.success(response.text)
 
-# Footer
+# -------------------------------------------------
+# 4️⃣  Footer
+# -------------------------------------------------
 st.markdown("---")
 st.markdown("🛠️ **Built with Streamlit & Google Gemini AI** | ❤️ _Happy Coding!_ 🐍")