from django.http.response import HttpResponseRedirect
from django.utils.translation import ugettext_lazy as _
from urllib.parse import urlencode
from django.views import View
from django.conf import settings
from django.http.request import HttpRequest
from django.db.utils import IntegrityError
from rest_framework.permissions import IsAuthenticated, AllowAny
from rest_framework.exceptions import APIException

from users.models import User
from users.views import UserVerifyPasswordView
from common.utils import get_logger, FlashMessageUtil
from common.utils.random import random_string
from common.utils.django import reverse, get_object_or_none
from common.sdk.im.dingtalk import URL
from common.mixins.views import UserConfirmRequiredExceptionMixin, PermissionsMixin
from common.permissions import UserConfirmation
from authentication import errors
from authentication.mixins import AuthMixin
from authentication.const import ConfirmType
from common.sdk.im.dingtalk import DingTalk
from common.utils.common import get_request_ip
from authentication.notifications import OAuthBindMessage
from .mixins import METAMixin

logger = get_logger(__file__)


DINGTALK_STATE_SESSION_KEY = '_dingtalk_state'


class DingTalkBaseMixin(UserConfirmRequiredExceptionMixin, PermissionsMixin, View):
    def dispatch(self, request, *args, **kwargs):
        try:
            return super().dispatch(request, *args, **kwargs)
        except APIException as e:
            try:
                msg = e.detail['errmsg']
            except Exception:
                msg = _('DingTalk Error, Please contact your system administrator')
            return self.get_failed_response(
                '/',
                _('DingTalk Error'),
                msg
            )

    def verify_state(self):
        state = self.request.GET.get('state')
        session_state = self.request.session.get(DINGTALK_STATE_SESSION_KEY)
        if state != session_state:
            return False
        return True

    def get_verify_state_failed_response(self, redirect_uri):
        msg = _("The system configuration is incorrect. Please contact your administrator")
        return self.get_failed_response(redirect_uri, msg, msg)

    @staticmethod
    def get_success_response(redirect_url, title, msg):
        message_data = {
            'title': title,
            'message': msg,
            'interval': 5,
            'redirect_url': redirect_url,
        }
        return FlashMessageUtil.gen_and_redirect_to(message_data)

    @staticmethod
    def get_failed_response(redirect_url, title, msg):
        message_data = {
            'title': title,
            'error': msg,
            'interval': 5,
            'redirect_url': redirect_url,
        }
        return FlashMessageUtil.gen_and_redirect_to(message_data)

    def get_already_bound_response(self, redirect_url):
        msg = _('DingTalk is already bound')
        response = self.get_failed_response(redirect_url, msg, msg)
        return response


class DingTalkQRMixin(DingTalkBaseMixin, View):

    def get_qr_url(self, redirect_uri):
        state = random_string(16)
        self.request.session[DINGTALK_STATE_SESSION_KEY] = state

        params = {
            'appid': settings.DINGTALK_APPKEY,
            'response_type': 'code',
            'scope': 'snsapi_login',
            'state': state,
            'redirect_uri': redirect_uri,
        }
        url = URL.QR_CONNECT + '?' + urlencode(params)
        return url


class DingTalkOAuthMixin(DingTalkBaseMixin, View):

    def get_oauth_url(self, redirect_uri):
        if not settings.AUTH_DINGTALK:
            return reverse('authentication:login')
        state = random_string(16)
        self.request.session[DINGTALK_STATE_SESSION_KEY] = state

        params = {
            'appid': settings.DINGTALK_APPKEY,
            'response_type': 'code',
            'scope': 'snsapi_auth',
            'state': state,
            'redirect_uri': redirect_uri,
        }
        url = URL.OAUTH_CONNECT + '?' + urlencode(params)
        return url


class DingTalkQRBindView(DingTalkQRMixin, View):
    permission_classes = (IsAuthenticated, UserConfirmation.require(ConfirmType.ReLogin))

    def get(self, request: HttpRequest):
        user = request.user
        redirect_url = request.GET.get('redirect_url')

        redirect_uri = reverse('authentication:dingtalk-qr-bind-callback', kwargs={'user_id': user.id}, external=True)
        redirect_uri += '?' + urlencode({'redirect_url': redirect_url})

        url = self.get_qr_url(redirect_uri)
        return HttpResponseRedirect(url)


class DingTalkQRBindCallbackView(DingTalkQRMixin, View):
    permission_classes = (IsAuthenticated,)

    def get(self, request: HttpRequest, user_id):
        code = request.GET.get('code')
        redirect_url = request.GET.get('redirect_url')

        if not self.verify_state():
            return self.get_verify_state_failed_response(redirect_url)

        user = get_object_or_none(User, id=user_id)
        if user is None:
            logger.error(f'DingTalkQR bind callback error, user_id invalid: user_id={user_id}')
            msg = _('Invalid user_id')
            response = self.get_failed_response(redirect_url, msg, msg)
            return response

        if user.dingtalk_id:
            response = self.get_already_bound_response(redirect_url)
            return response

        dingtalk = DingTalk(
            appid=settings.DINGTALK_APPKEY,
            appsecret=settings.DINGTALK_APPSECRET,
            agentid=settings.DINGTALK_AGENTID
        )
        userid = dingtalk.get_userid_by_code(code)

        if not userid:
            msg = _('DingTalk query user failed')
            response = self.get_failed_response(redirect_url, msg, msg)
            return response

        try:
            user.dingtalk_id = userid
            user.save()
        except IntegrityError as e:
            if e.args[0] == 1062:
                msg = _('The DingTalk is already bound to another user')
                response = self.get_failed_response(redirect_url, msg, msg)
                return response
            raise e

        ip = get_request_ip(request)
        OAuthBindMessage(user, ip, _('DingTalk'), user_id).publish_async()
        msg = _('Binding DingTalk successfully')
        response = self.get_success_response(redirect_url, msg, msg)
        return response


class DingTalkEnableStartView(UserVerifyPasswordView):

    def get_success_url(self):
        referer = self.request.META.get('HTTP_REFERER')
        redirect_url = self.request.GET.get("redirect_url")

        success_url = reverse('authentication:dingtalk-qr-bind')

        success_url += '?' + urlencode({
            'redirect_url': redirect_url or referer
        })

        return success_url


class DingTalkQRLoginView(DingTalkQRMixin, METAMixin, View):
    permission_classes = (AllowAny,)

    def get(self,  request: HttpRequest):
        redirect_url = request.GET.get('redirect_url') or reverse('index')
        next_url = self.get_next_url_from_meta() or reverse('index')

        redirect_uri = reverse('authentication:dingtalk-qr-login-callback', external=True)
        redirect_uri += '?' + urlencode({
            'redirect_url': redirect_url,
            'next': next_url,
        })

        url = self.get_qr_url(redirect_uri)
        return HttpResponseRedirect(url)


class DingTalkQRLoginCallbackView(AuthMixin, DingTalkQRMixin, View):
    permission_classes = (AllowAny,)

    def get(self, request: HttpRequest):
        code = request.GET.get('code')
        redirect_url = request.GET.get('redirect_url')
        login_url = reverse('authentication:login')

        if not self.verify_state():
            return self.get_verify_state_failed_response(redirect_url)

        dingtalk = DingTalk(
            appid=settings.DINGTALK_APPKEY,
            appsecret=settings.DINGTALK_APPSECRET,
            agentid=settings.DINGTALK_AGENTID
        )
        userid = dingtalk.get_userid_by_code(code)
        if not userid:
            # 正常流程不会出这个错误，hack 行为
            msg = _('Failed to get user from DingTalk')
            response = self.get_failed_response(login_url, title=msg, msg=msg)
            return response

        user = get_object_or_none(User, dingtalk_id=userid)
        if user is None:
            title = _('DingTalk is not bound')
            msg = _('Please login with a password and then bind the DingTalk')
            response = self.get_failed_response(login_url, title=title, msg=msg)
            return response

        try:
            self.check_oauth2_auth(user, settings.AUTH_BACKEND_DINGTALK)
        except errors.AuthFailedError as e:
            self.set_login_failed_mark()
            msg = e.msg
            response = self.get_failed_response(login_url, title=msg, msg=msg)
            return response

        return self.redirect_to_guard_view()


class DingTalkOAuthLoginView(DingTalkOAuthMixin, View):
    permission_classes = (AllowAny,)

    def get(self,  request: HttpRequest):
        redirect_url = request.GET.get('redirect_url')

        redirect_uri = reverse('authentication:dingtalk-oauth-login-callback', external=True)
        redirect_uri += '?' + urlencode({'redirect_url': redirect_url})

        url = self.get_oauth_url(redirect_uri)
        return HttpResponseRedirect(url)


class DingTalkOAuthLoginCallbackView(AuthMixin, DingTalkOAuthMixin, View):
    permission_classes = (AllowAny,)

    def get(self, request: HttpRequest):
        code = request.GET.get('code')
        redirect_url = request.GET.get('redirect_url')
        login_url = reverse('authentication:login')

        if not self.verify_state():
            return self.get_verify_state_failed_response(redirect_url)

        dingtalk = DingTalk(
            appid=settings.DINGTALK_APPKEY,
            appsecret=settings.DINGTALK_APPSECRET,
            agentid=settings.DINGTALK_AGENTID
        )
        userid = dingtalk.get_userid_by_code(code)
        if not userid:
            # 正常流程不会出这个错误，hack 行为
            msg = _('Failed to get user from DingTalk')
            response = self.get_failed_response(login_url, title=msg, msg=msg)
            return response

        user = get_object_or_none(User, dingtalk_id=userid)
        if user is None:
            title = _('DingTalk is not bound')
            msg = _('Please login with a password and then bind the DingTalk')
            response = self.get_failed_response(login_url, title=title, msg=msg)
            return response

        try:
            self.check_oauth2_auth(user, settings.AUTH_BACKEND_DINGTALK)
        except errors.AuthFailedError as e:
            self.set_login_failed_mark()
            msg = e.msg
            response = self.get_failed_response(login_url, title=msg, msg=msg)
            return response

        return self.redirect_to_guard_view()