from urllib.parse import urlencode
from uuid import uuid4
import logging

from django.shortcuts import redirect, render
from django.conf import settings
from django.urls import reverse
from django.core.exceptions import PermissionDenied
from django.http import HttpResponseBadRequest
from django.contrib.auth.forms import UserCreationForm
from django.utils.dateparse import parse_datetime

import withings.api
import withings.models
import gotify.api
import gotify.models
from medwings.forms import ProfileForm


def register_init(request):
    if request.user.is_authenticated:
        raise PermissionDenied('You are already registered and logged in.')

    # Generate a unique token and save it for later
    request.session.flush()
    spoof_protection_token = str(uuid4())
    request.session['spoof_protection_token'] = spoof_protection_token

    auth_url_base = 'https://account.withings.com/oauth2_user/authorize2'
    auth_url_params = {
        'response_type': 'code',
        'client_id': settings.WITHINGS_CONFIG['CLIENT_ID'],
        'scope': 'user.metrics,user.activity',
        'redirect_uri': request.build_absolute_uri(reverse('register-continue')),
        'state': spoof_protection_token
    }
    auth_url = f"{auth_url_base}?{urlencode(auth_url_params)}"

    context = {
        "auth_url": auth_url
    }

    return render(request, 'authentication/register-init.html', context)


def register_continue(request):
    if request.user.is_authenticated:
        raise PermissionDenied('You are already registered and logged in.')

    authorization_code = request.GET.get('code')
    authorization_state = request.GET.get('state')
    if not authorization_code:
        return HttpResponseBadRequest()
    if not authorization_state:
        return HttpResponseBadRequest()
    if not request.session.get('spoof_protection_token', None) == authorization_state:
        return HttpResponseBadRequest()

    if request.method == 'POST':
        user_form = UserCreationForm(request.POST)
        profile_form = ProfileForm(request.POST)

        if user_form.is_valid() and profile_form.is_valid():
            user = user_form.save(commit=False)
            profile = profile_form.save(commit=False)
            profile.user = user

            # Fetch access and refresh tokens and save them to session storage
            redirect_uri = request.build_absolute_uri(reverse('register-continue'))
            response_data = withings.api.fetch_initial_tokens(authorization_code, redirect_uri)
            if response_data['status'] != 0:
                return HttpResponseBadRequest()
            withings.api.save_tokens_to_session(request, response_data)

            user_password = request.POST.get('password1')
            gotify_user_info = gotify.api.create_user(user.username, user_password)
            gotify_app_info = gotify.api.create_application(user.username, user_password)
            gotify_user = gotify.models.GotifyUser(
                user=user,
                id=gotify_user_info['id']
            )
            gotify_app = gotify.models.GotifyApplication(
                user=gotify_user,
                id=gotify_app_info['id'],
                token=gotify_app_info['token']
            )

            withings_api_account = withings.models.ApiAccount(
                user=user,
                userid=request.session.get('withings_userid')
            )
            withings_access_token = withings.models.AccessToken(
                account=withings_api_account,
                value=request.session.get('withings_access_token'),
                expires=parse_datetime(request.session.get('withings_access_token_expiry'))
            )
            withings_refresh_token = withings.models.RefreshToken(
                account=withings_api_account,
                value=request.session.get('withings_refresh_token'),
                expires=parse_datetime(request.session.get('withings_refresh_token_expiry'))
            )

            for instance in [
                user, profile,
                gotify_user, gotify_app,
                withings_api_account, withings_access_token, withings_refresh_token
            ]:
                instance.save()
            request.session.flush()

            withings_api_account.update_records()

            # TODO redirect user to some other page and ask them to log in
            return redirect('dashboard')

    else:
        user_form = UserCreationForm()
        profile_form = ProfileForm()

    context = {
        'user_form': user_form,
        'profile_form': profile_form,
    }

    return render(request, 'authentication/register-continue.html', context)


def register_finalize(request):
    if request.user.is_authenticated:
        raise PermissionDenied('You are already registered and logged in.')

    # TODO implement

    return render(request, 'authentication/register-finalize.html')