from fastapi import FastAPI
import sqlite3
from hashlib import sha256
import streamlit as st
from openai import OpenAI
app  =FastAPI()
client = OpenAI()
# Step 1: Initialize the SQLite database
def init_db():
    conn = sqlite3.connect('user_data.db')  # Connect to SQLite database
    c = conn.cursor()
    
    # Create the users table if it doesn't exist
    c.execute('''CREATE TABLE IF NOT EXISTS users (
                 id INTEGER PRIMARY KEY AUTOINCREMENT, 
                 username TEXT NOT NULL, 
                 password TEXT NOT NULL)''')
    
    # Create a table for storing user inputs
    c.execute('''CREATE TABLE IF NOT EXISTS user_inputs (
                 id INTEGER PRIMARY KEY AUTOINCREMENT, 
                 username TEXT NOT NULL, 
                 input1 TEXT NOT NULL, 
                 input2 TEXT NOT NULL, 
                 input3 TEXT NOT NULL)''')
    
    conn.commit()
    return conn, c

# Step 2: Hash passwords for secure storage
def hash_password(password):
    return sha256(password.encode()).hexdigest()

# Step 3: Verify if the username and password match any record in the database
def verify_login(username, password, c):
    hashed_pw = hash_password(password)
    c.execute('SELECT * FROM users WHERE username=? AND password=?', (username, hashed_pw))
    return c.fetchone()

# Step 4: Create a new user (for initial setup)
def create_user(username, password, conn, c):
    hashed_pw = hash_password(password)
    c.execute('INSERT INTO users (username, password) VALUES (?, ?)', (username, hashed_pw))
    conn.commit()

# Step 5: Insert the user inputs into the database
def insert_user_inputs(username, input1, input2, input3, conn, c):
    c.execute('INSERT INTO user_inputs (username, input1, input2, input3) VALUES (?, ?, ?, ?)', 
              (username, input1, input2, input3))
    conn.commit()
def generate(input1,input2,input3):
    prompt = f"Using these three inputs: '{input1}' and '{input2}' and {input3}, first input we received from customner 2nd input we have to send also consider input 3 for morte accurate message write a mail which is more empathy based, formalized for business use, should address the issue well, positive tonality and dont make any assumption just write the mail"
    completion = client.chat.completions.create(
    model="gpt-4o-mini",
    messages=[
        {"role": "system", "content": "You are a helpful assistant who writes mail formally, and grammatically corrected."},
        {
            "role": "user",
            "content": prompt
        }
            ]
                )
    return completion.choices[0].message.content   
# Initialize the database and cursor
conn, c = init_db()

# Create a session state to store login status
if 'logged_in' not in st.session_state:
    st.session_state['logged_in'] = False
if 'username' not in st.session_state:
    st.session_state['username'] = None

# Streamlit UI: Login Page
if not st.session_state['logged_in']:
    st.title("User Login")

    # Username and password inputs
    username = st.text_input("Username")
    password = st.text_input("Password", type="password")

    # Login button
    if st.button("Login"):
        if username and password:
            user = verify_login(username, password, c)
            if user:
                st.session_state['logged_in'] = True
                st.session_state['username'] = username
                st.success(f"Welcome, {username}! You have successfully logged in.")
            else:
                st.error("Invalid username or password. Please try again.")
        else:
            st.error("Please enter both username and password.")
else:
    # When the user is logged in, display the new section
    st.title(f"Welcome {st.session_state['username']}! Writing AI at your assitance")
    
    # Input fields
    input1 = st.text_input("Mail received from Customer")
    input2 = st.text_input("Mail EARC send to customer")
    input3 = st.text_input("Any input")
    
    # Submit inputs button
    if st.button("Submit Inputs"):
        if input1 and input2 and input3:
            insert_user_inputs(st.session_state['username'], input1, input2, input3, conn, c)
            output = generate(input1, input2, input3)
            
            st.success(output)
        else:
            st.error("Please fill in all the fields.")

# (Optional) Add a section for creating new users, useful for testing
st.subheader("Create a new account (for testing)")
new_username = st.text_input("New Username")
new_password = st.text_input("New Password", type="password")

if st.button("Create Account"):
    if new_username and new_password:
        create_user(new_username, new_password, conn, c)
        st.success(f"Account created successfully for {new_username}!")
    else:
        st.error("Please enter both a username and a password.")

# Close the database connection when done
conn.close()