# ~*~ coding: utf-8 ~*~
#
from __future__ import unicode_literals
import os
import pyotp
import base64
import logging
import uuid

import requests
import ipaddress
from django.http import Http404
from django.conf import settings
from django.contrib.auth.mixins import UserPassesTestMixin
from django.contrib.auth import authenticate, login as auth_login
from django.utils.translation import ugettext as _
from django.core.cache import cache

from common.tasks import send_mail_async
from common.utils import reverse, get_object_or_none
from .models import User, LoginLog

logger = logging.getLogger('jumpserver')


class AdminUserRequiredMixin(UserPassesTestMixin):
    def test_func(self):
        if not self.request.user.is_authenticated:
            return False
        elif not self.request.user.is_superuser:
            self.raise_exception = True
            return False
        return True


def send_user_created_mail(user):
    subject = _('Create account successfully')
    recipient_list = [user.email]
    message = _("""
    Hello %(name)s:
    </br>
    Your account has been created successfully
    </br>
    Username: %(username)s
    </br>
    <a href="%(rest_password_url)s?token=%(rest_password_token)s">click here to set your password</a>
    </br>
    This link is valid for 1 hour. After it expires, <a href="%(forget_password_url)s?email=%(email)s">request new one</a>

    </br>
    ---

    </br>
    <a href="%(login_url)s">Login direct</a>

    </br>
    """) % {
        'name': user.name,
        'username': user.username,
        'rest_password_url': reverse('users:reset-password', external=True),
        'rest_password_token': user.generate_reset_token(),
        'forget_password_url': reverse('users:forgot-password', external=True),
        'email': user.email,
        'login_url': reverse('users:login', external=True),
    }
    if settings.DEBUG:
        try:
            print(message)
        except OSError:
            pass

    send_mail_async.delay(subject, message, recipient_list, html_message=message)


def send_reset_password_mail(user):
    subject = _('Reset password')
    recipient_list = [user.email]
    message = _("""
    Hello %(name)s:
    </br>
    Please click the link below to reset your password, if not your request, concern your account security
    </br>
    <a href="%(rest_password_url)s?token=%(rest_password_token)s">Click here reset password</a>
    </br>
    This link is valid for 1 hour. After it expires, <a href="%(forget_password_url)s?email=%(email)s">request new one</a>

    </br>
    ---

    </br>
    <a href="%(login_url)s">Login direct</a>

    </br>
    """) % {
        'name': user.name,
        'rest_password_url': reverse('users:reset-password', external=True),
        'rest_password_token': user.generate_reset_token(),
        'forget_password_url': reverse('users:forgot-password', external=True),
        'email': user.email,
        'login_url': reverse('users:login', external=True),
    }
    if settings.DEBUG:
        logger.debug(message)

    send_mail_async.delay(subject, message, recipient_list, html_message=message)


def send_reset_ssh_key_mail(user):
    subject = _('SSH Key Reset')
    recipient_list = [user.email]
    message = _("""
    Hello %(name)s:
    </br>
    Your ssh public key has been reset by site administrator.
    Please login and reset your ssh public key.
    </br>
    <a href="%(login_url)s">Login direct</a>

    </br>
    """) % {
        'name': user.name,
        'login_url': reverse('users:login', external=True),
    }
    if settings.DEBUG:
        logger.debug(message)

    send_mail_async.delay(subject, message, recipient_list, html_message=message)


def check_user_valid(**kwargs):
    password = kwargs.pop('password', None)
    public_key = kwargs.pop('public_key', None)
    email = kwargs.pop('email', None)
    username = kwargs.pop('username', None)

    if username:
        user = get_object_or_none(User, username=username)
    elif email:
        user = get_object_or_none(User, email=email)
    else:
        user = None

    if user is None:
        return None, _('User not exist')
    elif not user.is_valid:
        return None, _('Disabled or expired')

    if password and authenticate(username=username, password=password):
        return user, ''

    if public_key and user.public_key:
        public_key_saved = user.public_key.split()
        if len(public_key_saved) == 1:
            if public_key == public_key_saved[0]:
                return user, ''
        elif len(public_key_saved) > 1:
            if public_key == public_key_saved[1]:
                return user, ''
    return None, _('Password or SSH public key invalid')


def refresh_token(token, user, expiration=settings.TOKEN_EXPIRATION or 3600):
    cache.set(token, user.id, expiration)


def generate_token(request, user):
    expiration = settings.TOKEN_EXPIRATION or 3600
    remote_addr = request.META.get('REMOTE_ADDR', '')
    if not isinstance(remote_addr, bytes):
        remote_addr = remote_addr.encode("utf-8")
    remote_addr = base64.b16encode(remote_addr)  # .replace(b'=', '')
    token = cache.get('%s_%s' % (user.id, remote_addr))
    if not token:
        token = uuid.uuid4().hex
        cache.set(token, user.id, expiration)
        cache.set('%s_%s' % (user.id, remote_addr), token, expiration)
    return token


def validate_ip(ip):
    try:
        ipaddress.ip_address(ip)
        return True
    except ValueError:
        pass
    return False


def get_login_ip(request):
    x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR', '').split(',')
    if x_forwarded_for and x_forwarded_for[0]:
        login_ip = x_forwarded_for[0]
    else:
        login_ip = request.META.get('REMOTE_ADDR', '')

    return login_ip


def write_login_log(username, type='', ip='', user_agent=''):
    if not (ip and validate_ip(ip)):
        ip = ip[:15]
        city = "Unknown"
    else:
        city = get_ip_city(ip)
    LoginLog.objects.create(
        username=username, type=type,
        ip=ip, city=city, user_agent=user_agent
    )


def get_ip_city(ip, timeout=10):
    # Taobao ip api: http://ip.taobao.com//service/getIpInfo.php?ip=8.8.8.8
    # Sina ip api: http://int.dpool.sina.com.cn/iplookup/iplookup.php?ip=8.8.8.8&format=json

    url = 'http://int.dpool.sina.com.cn/iplookup/iplookup.php?ip=%s&format=json' % ip
    try:
        r = requests.get(url, timeout=timeout)
    except:
        r = None
    city = 'Unknown'
    if r and r.status_code == 200:
        try:
            data = r.json()
            if not isinstance(data, int) and data['ret'] == 1:
                city = data['country'] + ' ' + data['city']
        except ValueError:
            pass
    return city


def get_user_or_tmp_user(request):
    user = request.user
    tmp_user = get_tmp_user_from_cache(request)
    if user.is_authenticated:
        return user
    elif tmp_user:
        return tmp_user
    else:
        raise Http404("Not found this user")


def get_tmp_user_from_cache(request):
    if not request.session.session_key:
        return None
    user = cache.get(request.session.session_key+'user')
    return user


def set_tmp_user_to_cache(request, user):
    cache.set(request.session.session_key+'user', user, 600)


def redirect_user_first_login_or_index(request, redirect_field_name):
    if request.user.is_first_login:
        return reverse('users:user-first-login')
    return request.POST.get(
        redirect_field_name,
        request.GET.get(redirect_field_name, reverse('index')))


def generate_otp_uri(request, issuer="Jumpserver"):
    user = get_user_or_tmp_user(request)
    otp_secret_key = cache.get(request.session.session_key+'otp_key', '')
    if not otp_secret_key:
        otp_secret_key = base64.b32encode(os.urandom(10)).decode('utf-8')
    cache.set(request.session.session_key+'otp_key', otp_secret_key, 600)
    totp = pyotp.TOTP(otp_secret_key)
    return totp.provisioning_uri(name=user.username, issuer_name=issuer)


def check_otp_code(otp_secret_key, otp_code):
    totp = pyotp.TOTP(otp_secret_key)
    return totp.verify(otp_code)