from datetime import datetime
from flask import abort, flash, redirect, render_template, request, url_for
from flask_login import current_user, login_user, login_required, logout_user
from sqlalchemy import or_
from . import bp
from .forms import (LoginForm, ResetPasswordForm, ResetPasswordRequestForm,
                    RegistrationForm)
from .. import db
from ..email import create_message, send
from ..models import User
import logging
import os


@bp.before_app_request
def before_request():
    """
    Checks if a user is unconfirmed when visiting specific sites. Redirects to
    unconfirmed view if user is unconfirmed.
    """
    if current_user.is_authenticated:
        current_user.last_seen = datetime.utcnow()
        db.session.commit()
        if (not current_user.confirmed
                and request.endpoint
                and request.blueprint != 'auth'
                and request.endpoint != 'static'):
            return redirect(url_for('auth.unconfirmed'))


@bp.route('/login', methods=['GET', 'POST'])
def login():
    if current_user.is_authenticated:
        return redirect(url_for('main.dashboard'))
    form = LoginForm(prefix='login-form')
    if form.validate_on_submit():
        user = User.query.filter(or_(User.username == form.user.data,
                                     User.email == form.user.data.lower())).first()
        if user and user.verify_password(form.password.data):
            login_user(user, form.remember_me.data)
            next = request.args.get('next')
            if next is None or not next.startswith('/'):
                next = url_for('main.dashboard')
            return redirect(next)
        flash('Invalid email/username or password.')
    return render_template('auth/login.html.j2', form=form, title='Log in')


@bp.route('/logout')
@login_required
def logout():
    logout_user()
    flash('You have been logged out.')
    return redirect(url_for('main.index'))


@bp.route('/register', methods=['GET', 'POST'])
def register():
    if current_user.is_authenticated:
        return redirect(url_for('main.dashboard'))
    form = RegistrationForm(prefix='registration-form')
    if form.validate_on_submit():
        user = User(email=form.email.data.lower(),
                    password=form.password.data,
                    username=form.username.data)
        db.session.add(user)
        db.session.commit()
        try:
            os.makedirs(user.path)
        except OSError:
            logging.error('Make dir {} led to an OSError!'.format(user.path))
            db.session.delete(user)
            db.session.commit()
            abort(500)
        else:
            token = user.generate_confirmation_token()
            msg = create_message(user.email, 'Confirm Your Account',
                                 'auth/email/confirm', token=token, user=user)
            send(msg)
            flash('A confirmation email has been sent to you by email.')
            return redirect(url_for('.login'))
    return render_template('auth/register.html.j2', form=form,
                           title='Register')


@bp.route('/confirm/<token>')
@login_required
def confirm(token):
    if current_user.confirmed:
        return redirect(url_for('main.dashboard'))
    if current_user.confirm(token):
        db.session.commit()
        flash('You have confirmed your account. Thanks!')
        return redirect(url_for('main.dashboard'))
    else:
        flash('The confirmation link is invalid or has expired.')
        return redirect(url_for('.unconfirmed'))


@bp.route('/unconfirmed')
def unconfirmed():
    if current_user.is_anonymous:
        return redirect(url_for('main.index'))
    elif current_user.confirmed:
        return redirect(url_for('main.dashboard'))
    return render_template('auth/unconfirmed.html.j2', title='Unconfirmed')


@bp.route('/confirm')
@login_required
def resend_confirmation():
    token = current_user.generate_confirmation_token()
    msg = create_message(current_user.email, 'Confirm Your Account',
                         'auth/email/confirm', token=token, user=current_user)
    send(msg)
    flash('A new confirmation email has been sent to you by email.')
    return redirect(url_for('auth.unconfirmed'))


@bp.route('/reset', methods=['GET', 'POST'])
def reset_password_request():
    if current_user.is_authenticated:
        return redirect(url_for('main.dashboard'))
    form = ResetPasswordRequestForm(prefix='reset-password-request-form')
    if form.validate_on_submit():
        user = User.query.filter_by(email=form.email.data.lower()).first()
        if user is not None:
            token = user.generate_reset_token()
            msg = create_message(user.email, 'Reset Your Password',
                                 'auth/email/reset_password', token=token,
                                 user=user)
            send(msg)
        flash('An email with instructions to reset your password has been sent to you.')  # noqa
        return redirect(url_for('.login'))
    return render_template('auth/reset_password_request.html.j2', form=form,
                           title='Password Reset')


@bp.route('/reset/<token>', methods=['GET', 'POST'])
def reset_password(token):
    if current_user.is_authenticated:
        return redirect(url_for('main.dashboard'))
    form = ResetPasswordForm(prefix='reset-password-form')
    if form.validate_on_submit():
        if User.reset_password(token, form.password.data):
            db.session.commit()
            flash('Your password has been updated.')
            return redirect(url_for('.login'))
        else:
            return redirect(url_for('main.index'))
    return render_template('auth/reset_password.html.j2', form=form,
                           title='Password Reset', token=token)