from flask import (Flask, g, render_template, flash, redirect, url_for,
                   abort)
from flask.ext.bcrypt import check_password_hash
from flask.ext.login import (LoginManager, login_user, logout_user,
                             login_required, current_user)
from flask_mail import Message, Mail
from itsdangerous import URLSafeTimedSerializer, BadSignature, SignatureExpired

import forms
import models


app = Flask(__name__)
mail = Mail(app)

app.config.from_object('config.BaseConfig')


def generate_serializer(secret_key=None):
    return URLSafeTimedSerializer(app.config['SECRET_KEY'])


def generate_activation_url(user):
    serializer = generate_serializer()
    token = serializer.dumps(user.username)
    return url_for('activate_user', token=token, _external=True)


@app.before_request
def before_request():
    """Connect to the database before each request."""
    try:
        g.db = models.db
        g.db.connect()
        g.user = current_user
    except models.OperationalError:
        pass


@app.after_request
def after_request(response):
    """Close the database connection after each request."""
    g.db.close()
    return response


@app.route('/', methods=('GET', 'POST'))
def index():
    form = forms.RegisterForm()
    if form.validate_on_submit():
        models.User.create_user(
            username=form.username.data,
            email=form.email.data,
            password=form.password.data,
            confirmed=False
        )
        token = generate_activation_url(models.User)
        msg = Message(render_template('activation_email.html', token=token),
                      recipients=[models.User.email])
        mail.send(msg)

        return render_template('activate.html', user=models.User)
    return render_template('index.html', form=form)


@app.route('/activate/<token>')
def activate_user(token, expiration=3600):
    serializer = generate_serializer()
    try:
        user_id = serializer.loads(token, salt=app.config[
                                   'SECRET_KEY'], max_age=expiration)
    except (BadSignature, SignatureExpired):
        abort(404)

    models.User.confirmed = True
    flash('User activated')
    return redirect(url_for('index'))


if __name__ == '__main__':
    models.init()
    app.run(debug=True, host='localhost', port=8000)