class LoginForm(Form):
    #username and password text boxes and a submit button
    username = StringField('username', validators=[DataRequired()])
    password = PasswordField('password', validators=[DataRequired()])
    submit = SubmitField('Log In')

    # Response to a POST triggered by clicking the submit button
    def post(self):
        # Check that the submit button was clicked (not necessary: it's the only button, but hey)
        if self.submit.data:
            session = Database.DataSession()
            # Validate username and password
            if session.query(User).filter(and_(User.username==self.username.data, User.password == self.password.data)).count() > 0:
                session['valid'] = True
                return redirect("/main")
            else:
                return redirect("/")

    # Response to a GET request
    def get(self):
        return render_template('login.html',
                           title='Sign In',
                           year=datetime.now().year,
                           form=self)