import io
import json
import re
import uuid

import requests
from annoying.decorators import ajax_request
from annoying.functions import get_object_or_None
from django.contrib import messages
from django.contrib.auth.models import User
from django.core import management
from django.core.exceptions import FieldError
from django.core.files import File
from django.db.models import Q
from django.http import FileResponse, HttpResponse, JsonResponse
from django.shortcuts import redirect
from django.utils import timezone
from django.utils.formats import date_format
from django.utils.translation import gettext as _
from icalendar import Calendar, Event
from PIL import Image
from rest_framework import decorators, permissions, viewsets
from rest_framework.exceptions import APIException, PermissionDenied
from rest_framework.mixins import (ListModelMixin, RetrieveModelMixin,
                                   UpdateModelMixin, CreateModelMixin)
from rest_framework.parsers import MultiPartParser
from rest_framework.response import Response
from rest_framework.viewsets import ViewSetMixin

from cookbook.helper.permission_helper import (CustomIsAdmin, CustomIsGuest,
                                               CustomIsOwner, CustomIsShare,
                                               CustomIsShared, CustomIsUser,
                                               group_required)
from cookbook.helper.recipe_url_import import get_from_html
from cookbook.models import (CookLog, Food, Ingredient, Keyword, MealPlan,
                             MealType, Recipe, RecipeBook, ShoppingList,
                             ShoppingListEntry, ShoppingListRecipe, Step,
                             Storage, Sync, SyncLog, Unit, UserPreference,
                             ViewLog, RecipeBookEntry)
from cookbook.provider.dropbox import Dropbox
from cookbook.provider.nextcloud import Nextcloud
from cookbook.serializer import (FoodSerializer, IngredientSerializer,
                                 KeywordSerializer, MealPlanSerializer,
                                 MealTypeSerializer, RecipeBookSerializer,
                                 RecipeImageSerializer, RecipeSerializer,
                                 ShoppingListAutoSyncSerializer,
                                 ShoppingListEntrySerializer,
                                 ShoppingListRecipeSerializer,
                                 ShoppingListSerializer, StepSerializer,
                                 StorageSerializer, SyncLogSerializer,
                                 SyncSerializer, UnitSerializer,
                                 UserNameSerializer, UserPreferenceSerializer,
                                 ViewLogSerializer, CookLogSerializer, RecipeBookEntrySerializer, RecipeOverviewSerializer)
from recipes.settings import DEMO


class UserNameViewSet(viewsets.ReadOnlyModelViewSet):
    """
    list:
    optional parameters

    - **filter_list**: array of user id's to get names for
    """
    queryset = User.objects.all()
    serializer_class = UserNameSerializer
    permission_classes = [CustomIsGuest]
    http_method_names = ['get']

    def get_queryset(self):
        queryset = self.queryset
        try:
            filter_list = self.request.query_params.get('filter_list', None)
            if filter_list is not None:
                queryset = queryset.filter(pk__in=json.loads(filter_list))
        except ValueError:
            raise APIException(
                _('Parameter filter_list incorrectly formatted')
            )

        return queryset


class UserPreferenceViewSet(viewsets.ModelViewSet):
    queryset = UserPreference.objects.all()
    serializer_class = UserPreferenceSerializer
    permission_classes = [CustomIsOwner, ]

    def perform_create(self, serializer):
        if UserPreference.objects.filter(user=self.request.user).exists():
            raise APIException(_('Preference for given user already exists'))
        serializer.save(user=self.request.user)

    def get_queryset(self):
        if self.request.user.is_superuser:
            return self.queryset
        return self.queryset.filter(user=self.request.user)


class StorageViewSet(viewsets.ModelViewSet):
    # TODO handle delete protect error and adjust test
    queryset = Storage.objects.all()
    serializer_class = StorageSerializer
    permission_classes = [CustomIsAdmin, ]


class SyncViewSet(viewsets.ModelViewSet):
    queryset = Sync.objects.all()
    serializer_class = SyncSerializer
    permission_classes = [CustomIsAdmin, ]


class SyncLogViewSet(viewsets.ReadOnlyModelViewSet):
    queryset = SyncLog.objects.all()
    serializer_class = SyncLogSerializer
    permission_classes = [CustomIsAdmin, ]


class StandardFilterMixin(ViewSetMixin):

    def get_queryset(self):
        queryset = self.queryset
        query = self.request.query_params.get('query', None)
        if query is not None:
            queryset = queryset.filter(name__icontains=query)

        updated_at = self.request.query_params.get('updated_at', None)
        if updated_at is not None:
            try:
                queryset = queryset.filter(updated_at__gte=updated_at)
            except FieldError:
                pass

        limit = self.request.query_params.get('limit', None)
        random = self.request.query_params.get('random', False)
        if limit is not None:
            if random:
                queryset = queryset.random(int(limit))
            else:
                queryset = queryset[:int(limit)]
        return queryset


class KeywordViewSet(viewsets.ModelViewSet, StandardFilterMixin):
    """
       list:
       optional parameters

       - **query**: search keywords for a string contained
                    in the keyword name (case in-sensitive)
       - **limit**: limits the amount of returned results
       """
    queryset = Keyword.objects.all()
    serializer_class = KeywordSerializer
    permission_classes = [CustomIsUser]


class UnitViewSet(viewsets.ModelViewSet, StandardFilterMixin):
    queryset = Unit.objects.all()
    serializer_class = UnitSerializer
    permission_classes = [CustomIsUser]


class FoodViewSet(viewsets.ModelViewSet, StandardFilterMixin):
    queryset = Food.objects.all()
    serializer_class = FoodSerializer
    permission_classes = [CustomIsUser]


class RecipeBookViewSet(viewsets.ModelViewSet, StandardFilterMixin):
    queryset = RecipeBook.objects.all()
    serializer_class = RecipeBookSerializer
    permission_classes = [CustomIsOwner]

    def get_queryset(self):
        self.queryset = super(RecipeBookViewSet, self).get_queryset()
        if self.request.user.is_superuser:
            return self.queryset
        return self.queryset.filter(created_by=self.request.user)


class RecipeBookEntryViewSet(viewsets.ModelViewSet, viewsets.GenericViewSet):
    queryset = RecipeBookEntry.objects.all()
    serializer_class = RecipeBookEntrySerializer
    permission_classes = [CustomIsOwner, CustomIsAdmin]

    def get_queryset(self):
        if self.request.user.is_superuser:
            return self.queryset
        return self.queryset.filter(created_by=self.request.user)


class MealPlanViewSet(viewsets.ModelViewSet):
    """
    list:
    optional parameters

    - **from_date**: filter from (inclusive) a certain date onward
    - **to_date**: filter upward to (inclusive) certain date

    """
    queryset = MealPlan.objects.all()
    serializer_class = MealPlanSerializer
    permission_classes = [permissions.IsAuthenticated]  # TODO fix permissions

    def get_queryset(self):
        queryset = MealPlan.objects.filter(
            Q(created_by=self.request.user) |
            Q(shared=self.request.user)
        ).distinct().all()

        from_date = self.request.query_params.get('from_date', None)
        if from_date is not None:
            queryset = queryset.filter(date__gte=from_date)

        to_date = self.request.query_params.get('to_date', None)
        if to_date is not None:
            queryset = queryset.filter(date__lte=to_date)
        return queryset


class MealTypeViewSet(viewsets.ModelViewSet):
    """
    returns list of meal types created by the
    requesting user ordered by the order field.
    """
    queryset = MealType.objects.order_by('order').all()
    serializer_class = MealTypeSerializer
    permission_classes = [permissions.IsAuthenticated]

    def get_queryset(self):
        queryset = MealType.objects.order_by('order', 'id') \
            .filter(created_by=self.request.user).all()
        return queryset


class IngredientViewSet(viewsets.ModelViewSet):
    queryset = Ingredient.objects.all()
    serializer_class = IngredientSerializer
    permission_classes = [CustomIsUser]


class StepViewSet(viewsets.ModelViewSet):
    queryset = Step.objects.all()
    serializer_class = StepSerializer
    permission_classes = [CustomIsUser]


class RecipeViewSet(viewsets.ModelViewSet, StandardFilterMixin):
    """
    list:
    optional parameters

    - **query**: search recipes for a string contained
                 in the recipe name (case in-sensitive)
    - **limit**: limits the amount of returned results
    """
    queryset = Recipe.objects.all()
    serializer_class = RecipeSerializer
    # TODO split read and write permission for meal plan guest
    permission_classes = [CustomIsShare | CustomIsGuest]

    def get_queryset(self):

        internal = self.request.query_params.get('internal', None)
        if internal:
            self.queryset = self.queryset.filter(internal=True)

        return super().get_queryset()

    # TODO write extensive tests for permissions

    def get_serializer_class(self):
        if self.action == 'list':
            return RecipeOverviewSerializer
        return self.serializer_class

    @decorators.action(
        detail=True,
        methods=['PUT'],
        serializer_class=RecipeImageSerializer,
        parser_classes=[MultiPartParser],
    )
    def image(self, request, pk):
        obj = self.get_object()
        serializer = self.serializer_class(
            obj, data=request.data, partial=True
        )

        if DEMO:
            raise PermissionDenied(detail='Not available in demo', code=None)

        if serializer.is_valid():
            serializer.save()
            img = Image.open(obj.image)

            basewidth = 720
            wpercent = (basewidth / float(img.size[0]))
            hsize = int((float(img.size[1]) * float(wpercent)))
            img = img.resize((basewidth, hsize), Image.ANTIALIAS)

            im_io = io.BytesIO()
            img.save(im_io, 'PNG', quality=70)
            obj.image = File(im_io, name=f'{uuid.uuid4()}_{obj.pk}.png')
            obj.save()

            return Response(serializer.data)
        return Response(serializer.errors, 400)


class ShoppingListRecipeViewSet(viewsets.ModelViewSet):
    queryset = ShoppingListRecipe.objects.all()
    serializer_class = ShoppingListRecipeSerializer
    permission_classes = [CustomIsUser, ]  # TODO add custom validation

    # TODO custom get qs


class ShoppingListEntryViewSet(viewsets.ModelViewSet):
    queryset = ShoppingListEntry.objects.all()
    serializer_class = ShoppingListEntrySerializer
    permission_classes = [CustomIsOwner, ]  # TODO add custom validation

    # TODO custom get qs


class ShoppingListViewSet(viewsets.ModelViewSet):
    queryset = ShoppingList.objects.all()
    serializer_class = ShoppingListSerializer
    permission_classes = [CustomIsOwner | CustomIsShared]

    def get_queryset(self):
        if self.request.user.is_superuser:
            return self.queryset
        return self.queryset.filter(
            Q(created_by=self.request.user) | Q(shared=self.request.user)
        ).all()

    def get_serializer_class(self):
        autosync = self.request.query_params.get('autosync', None)
        if autosync:
            return ShoppingListAutoSyncSerializer
        return self.serializer_class


class ViewLogViewSet(viewsets.ModelViewSet):
    queryset = ViewLog.objects.all()
    serializer_class = ViewLogSerializer
    permission_classes = [permissions.IsAuthenticated]

    def get_queryset(self):
        queryset = ViewLog.objects \
                       .filter(created_by=self.request.user).all()[:5]
        return queryset


class CookLogViewSet(viewsets.ModelViewSet):
    queryset = CookLog.objects.all()
    serializer_class = CookLogSerializer
    permission_classes = [CustomIsOwner]

    def get_queryset(self):
        queryset = ViewLog.objects.filter(created_by=self.request.user).all()[:5]
        return queryset


# -------------- non django rest api views --------------------

def get_recipe_provider(recipe):
    if recipe.storage.method == Storage.DROPBOX:
        return Dropbox
    elif recipe.storage.method == Storage.NEXTCLOUD:
        return Nextcloud
    else:
        raise Exception('Provider not implemented')


def update_recipe_links(recipe):
    if not recipe.link:
        # TODO response validation in apis
        recipe.link = get_recipe_provider(recipe).get_share_link(recipe)

    recipe.save()


@group_required('user')
def get_external_file_link(request, recipe_id):
    recipe = Recipe.objects.get(id=recipe_id)
    if not recipe.link:
        update_recipe_links(recipe)

    return HttpResponse(recipe.link)


@group_required('user')
def get_recipe_file(request, recipe_id):
    recipe = Recipe.objects.get(id=recipe_id)
    if not recipe.cors_link:
        update_recipe_links(recipe)

    return FileResponse(get_recipe_provider(recipe).get_file(recipe))


@group_required('user')
def sync_all(request):
    if DEMO:
        messages.add_message(
            request, messages.ERROR, _('This feature is not available in the demo version!')
        )
        return redirect('index')

    monitors = Sync.objects.filter(active=True)

    error = False
    for monitor in monitors:
        if monitor.storage.method == Storage.DROPBOX:
            ret = Dropbox.import_all(monitor)
            if not ret:
                error = True
        if monitor.storage.method == Storage.NEXTCLOUD:
            ret = Nextcloud.import_all(monitor)
            if not ret:
                error = True

    if not error:
        messages.add_message(
            request, messages.SUCCESS, _('Sync successful!')
        )
        return redirect('list_recipe_import')
    else:
        messages.add_message(
            request, messages.ERROR, _('Error synchronizing with Storage')
        )
        return redirect('list_recipe_import')


@group_required('user')
@ajax_request
def log_cooking(request, recipe_id):
    recipe = get_object_or_None(Recipe, id=recipe_id)
    if recipe:
        log = CookLog.objects.create(created_by=request.user, recipe=recipe)
        servings = request.GET['s'] if 's' in request.GET else None
        if servings and re.match(r'^([1-9])+$', servings):
            log.servings = int(servings)

        rating = request.GET['r'] if 'r' in request.GET else None
        if rating and re.match(r'^([1-9])+$', rating):
            log.rating = int(rating)
        log.save()
        return {'msg': 'updated successfully'}

    return {'error': 'recipe does not exist'}


@group_required('user')
def get_plan_ical(request, from_date, to_date):
    queryset = MealPlan.objects.filter(
        Q(created_by=request.user) | Q(shared=request.user)
    ).distinct().all()

    if from_date is not None:
        queryset = queryset.filter(date__gte=from_date)

    if to_date is not None:
        queryset = queryset.filter(date__lte=to_date)

    cal = Calendar()

    for p in queryset:
        event = Event()
        event['uid'] = p.id
        event.add('dtstart', p.date)
        event.add('dtend', p.date)
        event['summary'] = f'{p.meal_type.name}: {p.get_label()}'
        event['description'] = p.note
        cal.add_component(event)

    response = FileResponse(io.BytesIO(cal.to_ical()))
    response["Content-Disposition"] = f'attachment; filename=meal_plan_{from_date}-{to_date}.ics'  # noqa: E501

    return response


@group_required('user')
def recipe_from_url(request):
    url = request.POST['url']

    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.106 Safari/537.36'  # noqa: E501
    }
    try:
        response = requests.get(url, headers=headers)
    except requests.exceptions.ConnectionError:
        return JsonResponse(
            {
                'error': True,
                'msg': _('The requested page could not be found.')
            },
            status=400
        )

    if response.status_code == 403:
        return JsonResponse(
            {
                'error': True,
                'msg': _('The requested page refused to provide any information (Status Code 403).')  # noqa: E501
            },
            status=400
        )
    return get_from_html(response.text, url)


def get_backup(request):
    if not request.user.is_superuser:
        return HttpResponse('', status=403)

    buf = io.StringIO()
    management.call_command(
        'dumpdata', exclude=['contenttypes', 'auth'], stdout=buf
    )

    response = FileResponse(buf.getvalue())
    response["Content-Disposition"] = f'attachment; filename=backup{date_format(timezone.now(), format="SHORT_DATETIME_FORMAT", use_l10n=True)}.json'  # noqa: E501

    return response