from flask import Blueprint, redirect, url_for, render_template, request, session
from functools import wraps
import time

from ..auth import (
    digest, verify, create_session,
    is_logged_in, parse_username, is_password_valid,
    login_required
    )
from ..models import Users
from ..constants import PermissionLevel
from secrets import compare_digest as compare_timesafe

bp = Blueprint('users', __name__, url_prefix='/users/')

def redirect_if_logged_in(destination='topics.all_topics'):
    def decorator(view_func):
        @wraps(view_func)
        def wrapper(*args, **kwargs):
            if is_logged_in():
                return redirect(url_for(destination))
            return view_func(*args, **kwargs)
        return wrapper
    return decorator

@bp.get('/log-in/')
@redirect_if_logged_in()
def log_in():
    return render_template('users/log_in.html')

@bp.post('/log-out/')
@login_required
def log_out():
    return 'stub'

@bp.post('/log-in/')
@redirect_if_logged_in()
def log_in_post():
    username = request.form.get('username', default='').lower()
    user = Users.find({'username': username})
    if not user:
        return redirect(url_for('.log_in', error='The username or password you entered is incorrect.'))
    password = request.form.get('password', default='')
    if not verify(user.password_hash, password):
        return redirect(url_for('.log_in', error='The username or password you entered is incorrect.'))

    session['remember'] = request.form.get('remember') == 'on'
    sess = create_session(user.id, not session['remember'])
    session['pyrom_session_key'] = sess.key
    if session['remember']:
        session.permanent = True
    return redirect(request.form.get('return_to', default=url_for('topics.all_topics')))

@bp.get('/sign-up/')
@redirect_if_logged_in()
def sign_up():
    return render_template('users/sign_up.html')

@bp.post('/sign-up/')
@redirect_if_logged_in()
def sign_up_post():
    generic_error_page = redirect(url_for('.sign_up', error='The username or password you entered is invalid.'))
    invalid_username_error_page = redirect(url_for('.sign_up', error='This username cannot be used. Please pick another.'))
    passwords_error_page = redirect(url_for('.sign_up', error='The passwords do not match.'))
    username = request.form.get('username', default='')
    if not username:
        return generic_error_page
    if request.form.get('password') is None:
        return generic_error_page
    if len(request.form.getlist('password')) != 2:
        return passwords_error_page
    try:
        username_pair = parse_username(username)
    except ValueError:
        return invalid_username_error_page
    potential_user = Users.find({'username': username})
    if potential_user:
        return invalid_username_error_page

    if not compare_timesafe(request.form.getlist('password')[0], request.form.getlist('password')[1]):
        return passwords_error_page

    password_hash = digest(request.form.get('password'))

    user = Users.create({
        'username': username_pair[0],
        'password_hash': password_hash,
        'permission': PermissionLevel.GUEST.value,
        'created_at': int(time.time()),
    })

    if username_pair[0] != username_pair[1]:
        user.update({
            'display_name': username_pair[1]
        })

    session['remember'] = request.form.get('remember') == 'on'
    sess = create_session(user.id, not session['remember'])
    session['pyrom_session_key'] = sess.key
    if session['remember']:
        session.permanent = True

    return redirect(url_for('topics.all_topics'))

@bp.get('/<username>/')
def user_page(username):
    target_user = Users.find({'username': username})
    if not target_user:
        abort(404)
    return render_template('users/user_page.html', target_user=target_user)

@bp.get('/<username>/posts/')
def posts(username):
    return 'stub'

@bp.get('/<username>/threads/')
def threads(username):
    return 'stub'

@bp.get('/<username>/comments/')
def comments(username):
    return 'stub'

@bp.get('/<username>/settings/')
def settings(username):
    return 'stub'

@bp.get('/<username>/inbox/')
def inbox(username):
    return 'stub'

@bp.get('/<username>/bookmarks/')
def bookmarks(username):
    return 'stub'