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

app = Flask(__name__)

app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///accounts.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.secret_key = 'super_secret_session_encryption_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)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(128), nullable=False)

with app.app_context():
    db.create_all()


@app.route('/submit-form', methods=['POST'])
def handle_submission():
    form_username = request.form.get('username')
    form_email = request.form.get('email')
    form_password = request.form.get('password')
    
    if User.query.filter_by(username=form_username).first():
        return "<h3>Username taken!</h3>", 400
    if User.query.filter_by(email=form_email).first():
        return "<h3>Email already registered!</h3>", 400
    
    hashed_password = generate_password_hash(form_password)
    
    new_user = User(username=form_username, email=form_email, password_hash=hashed_password)
    db.session.add(new_user)
    db.session.commit()
    
    return redirect(url_for('success'))

@app.route('/success')
def success():
    return "<h3>Data successfully saved to the database!</h3>"

@app.route('/users')
def view_users():
    all_users = User.query.all()
    
    html_output = "<h2>Registered Accounts</h2><table border='1' cellpadding='10'>"
    html_output += "<tr><th>ID</th><th>Username</th><th>Email</th></tr>"
    
    for user in all_users:
        html_output += f"<tr><td>{user.id}</td><td>{user.username}</td><td>{user.email}</td><td>{user.password_hash}</td></tr>"
        
    html_output += "</table>"
    
    if not all_users:
        return "<h3>No accounts found in the database yet.</h3>"
        
    return html_output


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

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

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

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

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

if __name__ == '__main__':
    app.run(debug=True)