Update app.py

app.py

@@ -1,39 +1,40 @@
 import streamlit as st
-from login import login
-from signup import signup
 import home
-import prediction
+import prediction 
 import about
 import contact
+import login_page as login  # Renamed login.py to login_page.py for clarity and to avoid naming conflicts
 
-# Initialize session state
-if 'logged_in' not in st.session_state:
-    st.session_state.logged_in = False
-if 'signup' not in st.session_state:
-    st.session_state.signup = False
+# ✅ Must be first Streamlit command
+st.set_page_config(page_title="TransPolymer", layout="wide", page_icon="🧪")
+
+# ✅ Ensure users collection exists
+login.create_users_collection()
 
-# Sign-up flow
-if st.session_state.signup:
-    signup()
+# ✅ Initialize login state
+if "logged_in" not in st.session_state:
+    st.session_state.logged_in = False
 
-# Logged-in flow
-elif st.session_state.logged_in:
-    st.sidebar.title("Navigation")
-    page = st.sidebar.radio("Go to", ("Home", "Prediction", "About", "Contact"))
+# ✅ Show login or main app
+if not st.session_state.logged_in:
+    login.show_login_page()
+else:
+    # ✅ Load Home page immediately after login
+    if "page" not in st.session_state:
+        st.session_state.page = "Home"
 
-    if st.sidebar.button("Logout"):
-        st.session_state.logged_in = False
+    # ✅ Sidebar navigation appears only after login
+    st.sidebar.title("🔗 Navigation")
+    st.session_state.page = st.sidebar.radio("Select a Page", ["Home", "Predictions", "About", "Help"], index=["Home", "Predictions", "About", "Help"].index(st.session_state.page))
 
-    if page == "Home":
+    # ✅ Load page dynamically
+    if st.session_state.page == "Home":
         home.show()
-    elif page == "Prediction":
+    elif st.session_state.page == "Predictions":
         prediction.show()
-    elif page == "About":
+    elif st.session_state.page == "About":
         about.show()
-    elif page == "Contact":
+    elif st.session_state.page == "Help":
         contact.show()
-
-# Login flow
-else:
-    if login():  # This now returns True when credentials are correct
-        st.session_state.logged_in = True
+    else:
+        st.error("Page not found.")