Code Editor for app.py

import streamlit as st
import pandas as pd
import plotly.express as px
import time
import random

# Initialize session state variables
if 'authenticated' not in st.session_state:
    st.session_state.authenticated = False
if 'messages' not in st.session_state:
    st.session_state.messages = []
if 'df' not in st.session_state:
    # Sample dataset
    st.session_state.df = pd.DataFrame({
        'Category': ['A', 'B', 'C', 'D', 'E'],
        'Values': [23, 45, 56, 78, 90]
    })

# Configure page
st.set_page_config(layout="wide")

# Sidebar with authentication
with st.sidebar:
    st.title("Login")
    with st.expander("Click to expand", expanded=not st.session_state.authenticated):
        if not st.session_state.authenticated:
            username = st.text_input("Username")
            password = st.text_input("Password", type="password")
            if st.button("Login"):
                # Simple authentication - in real app, use secure methods
                if username == "admin" and password == "password":
                    st.session_state.authenticated = True
                    st.success("Logged in successfully!")
                    st.rerun()
                else:
                    st.error("Invalid credentials")
        else:
            st.success("Logged in as admin")
            if st.button("Logout"):
                st.session_state.authenticated = False
                st.rerun()

# Main content
if st.session_state.authenticated:
    tab1, tab2 = st.tabs(["Data Visualization", "Chat Interface"])
    
    with tab1:
        st.title("Data Visualization")
        
        # Display data
        st.subheader("Sample Dataset")
        st.dataframe(st.session_state.df)
        
        # Create bar chart
        st.subheader("Bar Chart")
        fig = px.bar(st.session_state.df, x='Category', y='Values',
                    title='Sample Data Visualization')
        st.plotly_chart(fig, use_container_width=True)
    
    with tab2:
        st.title("Chat Interface")
        
        # Display chat messages
        for message in st.session_state.messages:
            with st.chat_message(message["role"]):
                st.write(message["content"])
        
        # Chat input
        if prompt := st.chat_input("Ask about the data"):
            # Add user message
            st.session_state.messages.append({"role": "user", "content": prompt})
            
            # Display user message
            with st.chat_message("user"):
                st.write(prompt)
            
            # Generate and display response
            with st.chat_message("assistant"):
                response = f"I understand you're asking about the data. The dataset contains {len(st.session_state.df)} rows with categories and their corresponding values. What specific information would you like to know?"
                st.write_stream(response)
            
            # Add assistant response to history
            st.session_state.messages.append({"role": "assistant", "content": response})

else:
    st.warning("Please log in to access the application")