import time
from django.core.cache import cache
from rest_framework.generics import CreateAPIView, ListAPIView
from rest_framework.views import APIView
from rest_framework.request import Request
from rest_framework.response import Response
from rest_framework import status
from drf_spectacular.utils import extend_schema, OpenApiParameter, OpenApiResponse

from .models import WeatherStats
from .serializers import WeatherStatSerializer
from .utils import IsMikrokontroller, PageNumberPagination

CACHE_SAVE_CONTROL = 'stats_latest_saved_control'
CACHE_KEY_STATS = 'stats_latest_data'
CACHE_KEY_WEATHER = 'weather_latest_data'
CACHE_TIMEOUT = 30 # 30 seconds

# Create your views here.
@extend_schema(tags=['Weather'],
    description="Call method by mikrocontroller to set new data (required MIKRO_SECRET_KEY with header X-Mikro-Key) with delay 30 seconds",
    parameters=[
        OpenApiParameter(
            name='X-Mikro-Key',
            type=str,
            location=OpenApiParameter.HEADER,
            description='Secret Key for microcontroller',
            required=True
        )
    ]
    )
class CreateStatAPI(CreateAPIView):
    serializer_class = WeatherStatSerializer
    permission_classes = [ IsMikrokontroller ]
    queryset = WeatherStats.objects.all()

    def perform_create(self, serializer: WeatherStatSerializer):
        new_data = serializer.validated_data
        last_saved = cache.get(CACHE_SAVE_CONTROL)
        current_time = time.time()
        
        if last_saved is None or (current_time - last_saved) >= CACHE_TIMEOUT:
            serializer.save()
            cache.set(CACHE_SAVE_CONTROL, current_time, CACHE_TIMEOUT)

        cache.set(CACHE_KEY_STATS, new_data, CACHE_TIMEOUT)


@extend_schema(tags=['Weather'],
               description="Get latest stat by microcontroller. Can be used to get actual data now",
               responses={
                   200: WeatherStatSerializer,
                   404: OpenApiResponse(
                        description="No latest data available from microcontroller",
                        response={
                            "message": "We don't have latest data from microcontroller"
                        }
                    )
               }
            )
class LastStatAPI(APIView):
    def get(self, request: Request, format=None):
        cached_data = cache.get(CACHE_KEY_STATS)

        if cached_data is None:
            return Response(
                {"message": "We don't have latest data from microcontroller. Maybe microcontroller is not connected"},
                status=status.HTTP_404_NOT_FOUND
            )

        return Response(cached_data)
    
@extend_schema(tags=['Weather'], description="Get full history for graph")
class StatsHistoryAPI(ListAPIView):
    serializer_class = WeatherStatSerializer
    queryset = WeatherStats.objects.order_by('-created_at')
    pagination_class = PageNumberPagination

class WeatherAPI(APIView):
    def get(self, request: Request, format=None):
        cached_data = cache.get(CACHE_KEY_WEATHER)

        if cached_data:
            return Response(cached_data)