"""
Parks API views following Django styleguide patterns.
Uses ClassNameApi naming convention and proper Input/Output serializers.
"""

from rest_framework.decorators import action
from rest_framework.request import Request
from rest_framework.response import Response
from rest_framework.viewsets import GenericViewSet
from rest_framework.permissions import (
    IsAuthenticated,
    IsAuthenticatedOrReadOnly,
)
from django_filters.rest_framework import DjangoFilterBackend
from rest_framework.filters import SearchFilter, OrderingFilter

from apps.core.api.mixins import (
    CreateApiMixin,
    UpdateApiMixin,
    ListApiMixin,
    RetrieveApiMixin,
    DestroyApiMixin,
)
from ..selectors import (
    park_list_with_stats,
    park_detail_optimized,
    park_reviews_for_park,
    park_statistics,
)
from ..services import ParkService
from .serializers import (
    ParkListOutputSerializer,
    ParkDetailOutputSerializer,
    ParkCreateInputSerializer,
    ParkUpdateInputSerializer,
    ParkFilterInputSerializer,
    ParkReviewOutputSerializer,
    ParkStatsOutputSerializer,
)


class ParkListApi(ListApiMixin, GenericViewSet):
    """
    API endpoint for listing parks with filtering and search.

    GET /api/v1/parks/
    """

    permission_classes = [IsAuthenticatedOrReadOnly]
    filter_backends = [DjangoFilterBackend, SearchFilter, OrderingFilter]
    search_fields = ["name", "description"]
    ordering_fields = [
        "name",
        "opening_date",
        "average_rating",
        "coaster_count",
        "created_at",
    ]
    ordering = ["name"]

    OutputSerializer = ParkListOutputSerializer
    FilterSerializer = ParkFilterInputSerializer

    def get_queryset(self):
        """Use selector to get optimized queryset."""
        # Parse filter parameters
        filter_serializer = self.FilterSerializer(data=self.request.query_params)
        filter_serializer.is_valid(raise_exception=True)
        filters = filter_serializer.validated_data

        return park_list_with_stats(filters=filters)

    @action(detail=False, methods=["get"])
    def stats(self, request: Request) -> Response:
        """
        Get park statistics.

        GET /api/v1/parks/stats/
        """
        stats = park_statistics()
        serializer = ParkStatsOutputSerializer(stats)

        return self.create_response(
            data=serializer.data,
            metadata={"cache_duration": 3600},  # 1 hour cache hint
        )


class ParkDetailApi(RetrieveApiMixin, GenericViewSet):
    """
    API endpoint for retrieving individual park details.

    GET /api/v1/parks/{id}/
    """

    permission_classes = [IsAuthenticatedOrReadOnly]
    lookup_field = "slug"

    OutputSerializer = ParkDetailOutputSerializer

    def get_object(self):
        """Use selector for optimized detail query."""
        slug = self.kwargs.get("slug")
        return park_detail_optimized(slug=slug)

    @action(detail=True, methods=["get"])
    def reviews(self, request: Request, slug: str = None) -> Response:
        """
        Get reviews for a specific park.

        GET /api/v1/parks/{slug}/reviews/
        """
        park = self.get_object()
        reviews = park_reviews_for_park(park_id=park.id, limit=50)

        serializer = ParkReviewOutputSerializer(reviews, many=True)

        return self.create_response(
            data=serializer.data,
            metadata={"total_reviews": len(reviews), "park_name": park.name},
        )


class ParkCreateApi(CreateApiMixin, GenericViewSet):
    """
    API endpoint for creating parks.

    POST /api/v1/parks/create/
    """

    permission_classes = [IsAuthenticated]

    InputSerializer = ParkCreateInputSerializer
    OutputSerializer = ParkDetailOutputSerializer

    def perform_create(self, **validated_data):
        """Create park using service layer."""
        return ParkService.create_park(**validated_data)


class ParkUpdateApi(UpdateApiMixin, RetrieveApiMixin, GenericViewSet):
    """
    API endpoint for updating parks.

    PUT /api/v1/parks/{slug}/update/
    PATCH /api/v1/parks/{slug}/update/
    """

    permission_classes = [IsAuthenticated]
    lookup_field = "slug"

    InputSerializer = ParkUpdateInputSerializer
    OutputSerializer = ParkDetailOutputSerializer

    def get_object(self):
        """Use selector for optimized detail query."""
        slug = self.kwargs.get("slug")
        return park_detail_optimized(slug=slug)

    def perform_update(self, instance, **validated_data):
        """Update park using service layer."""
        return ParkService.update_park(park_id=instance.id, **validated_data)


class ParkDeleteApi(DestroyApiMixin, RetrieveApiMixin, GenericViewSet):
    """
    API endpoint for deleting parks.

    DELETE /api/v1/parks/{slug}/delete/
    """

    permission_classes = [IsAuthenticated]  # TODO: Add staff/admin permission
    lookup_field = "slug"

    def get_object(self):
        """Use selector for optimized detail query."""
        slug = self.kwargs.get("slug")
        return park_detail_optimized(slug=slug)

    def perform_destroy(self, instance):
        """Delete park using service layer."""
        ParkService.delete_park(park_id=instance.id)


# Unified API ViewSet (alternative approach)
class ParkApi(
    CreateApiMixin,
    UpdateApiMixin,
    ListApiMixin,
    RetrieveApiMixin,
    DestroyApiMixin,
    GenericViewSet,
):
    """
    Unified API endpoint for parks with all CRUD operations.

    GET /api/v1/parks/ - List parks
    POST /api/v1/parks/ - Create park
    GET /api/v1/parks/{slug}/ - Get park detail
    PUT /api/v1/parks/{slug}/ - Update park
    PATCH /api/v1/parks/{slug}/ - Partial update park
    DELETE /api/v1/parks/{slug}/ - Delete park
    """

    permission_classes = [IsAuthenticatedOrReadOnly]
    lookup_field = "slug"
    filter_backends = [DjangoFilterBackend, SearchFilter, OrderingFilter]
    search_fields = ["name", "description"]
    ordering_fields = [
        "name",
        "opening_date",
        "average_rating",
        "coaster_count",
        "created_at",
    ]
    ordering = ["name"]

    # Serializers for different operations
    InputSerializer = ParkCreateInputSerializer  # Used for create
    UpdateInputSerializer = ParkUpdateInputSerializer  # Used for update
    OutputSerializer = ParkDetailOutputSerializer  # Used for retrieve
    ListOutputSerializer = ParkListOutputSerializer  # Used for list
    FilterSerializer = ParkFilterInputSerializer

    def get_queryset(self):
        """Use selector to get optimized queryset."""
        if self.action == "list":
            # Parse filter parameters for list view
            filter_serializer = self.FilterSerializer(data=self.request.query_params)
            filter_serializer.is_valid(raise_exception=True)
            filters = filter_serializer.validated_data
            return park_list_with_stats(**filters)

        # For detail views, this won't be used since we override get_object
        return []

    def get_object(self):
        """Use selector for optimized detail query."""
        slug = self.kwargs.get("slug")
        return park_detail_optimized(slug=slug)

    def get_output_serializer(self, *args, **kwargs):
        """Return appropriate output serializer based on action."""
        if self.action == "list":
            return self.ListOutputSerializer(*args, **kwargs)
        return self.OutputSerializer(*args, **kwargs)

    def get_input_serializer(self, *args, **kwargs):
        """Return appropriate input serializer based on action."""
        if self.action in ["update", "partial_update"]:
            return self.UpdateInputSerializer(*args, **kwargs)
        return self.InputSerializer(*args, **kwargs)

    def perform_create(self, **validated_data):
        """Create park using service layer."""
        return ParkService.create_park(**validated_data)

    def perform_update(self, instance, **validated_data):
        """Update park using service layer."""
        return ParkService.update_park(park_id=instance.id, **validated_data)

    def perform_destroy(self, instance):
        """Delete park using service layer."""
        ParkService.delete_park(park_id=instance.id)

    @action(detail=False, methods=["get"])
    def stats(self, request: Request) -> Response:
        """
        Get park statistics.

        GET /api/v1/parks/stats/
        """
        stats = park_statistics()
        serializer = ParkStatsOutputSerializer(stats)

        return self.create_response(
            data=serializer.data, metadata={"cache_duration": 3600}
        )

    @action(detail=True, methods=["get"])
    def reviews(self, request: Request, slug: str = None) -> Response:
        """
        Get reviews for a specific park.

        GET /api/v1/parks/{slug}/reviews/
        """
        park = self.get_object()
        reviews = park_reviews_for_park(park_id=park.id, limit=50)

        serializer = ParkReviewOutputSerializer(reviews, many=True)

        return self.create_response(
            data=serializer.data,
            metadata={"total_reviews": len(reviews), "park_name": park.name},
        )