main.py

from flask import Flask, render_template, request, redirect, url_for, flash
from flask_sqlalchemy import SQLAlchemy
from werkzeug.security import generate_password_hash, check_password_hash

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:////tmp/test.db'
app.config['SECRET_KEY'] = 'your-secret-key'  # replace with your secret key
db = SQLAlchemy(app)

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True, nullable=False)
    password = db.Column(db.String(120), nullable=False)

@app.route('/')
def home():
    return render_template('index.html')

@app.route('/login', methods=['POST'])
def login():
    username = request.form.get('username')
    password = request.form.get('password')
    user = User.query.filter_by(username=username).first()
    if user and check_password_hash(user.password, password):
        flash('Logged in successfully.')
        return redirect(url_for('test'))
    else:
        flash('Invalid username or password.')
        return redirect(url_for('home'))

@app.route('/test')
def test():
    return render_template('test.html')

if __name__ == '__main__':
    db.create_all()  # create tables
    app.run(debug=True)