from typing import AsyncGenerator
import strawberry
from channels.db import database_sync_to_async
from strawberry.types import Info
from core.graphql.pubsub import pubsub
from core.graphql.types.project import ProjectType
from core.graphql.utils import _extract_id
from core.models.project import Project


@strawberry.type
class Subscription:
    @strawberry.subscription(description="Subscribe to project creation events")
    async def project_created(self, info: Info) -> AsyncGenerator[ProjectType, None]:
        user = info.context.user
        if not user or not user.is_authenticated:
            raise PermissionError("Authentication required")

        async with pubsub.subscribe("project_created") as subscriber:
            async for payload in subscriber:
                project_id = await _extract_id(payload)
                try:
                    instance = await database_sync_to_async(Project.objects.get)(pk=project_id)
                except Project.DoesNotExist:
                    continue
                yield instance

    @strawberry.subscription(description="Subscribe to project updates")
    async def project_updated(self, info: Info) -> AsyncGenerator[ProjectType, None]:
        user = info.context.user
        if not user or not user.is_authenticated:
            raise PermissionError("Authentication required")

        async with pubsub.subscribe("project_updated") as subscriber:
            async for payload in subscriber:
                project_id = await _extract_id(payload)
                try:
                    instance = await database_sync_to_async(Project.objects.get)(pk=project_id)
                except Project.DoesNotExist:
                    continue
                yield instance

    @strawberry.subscription(description="Subscribe to project deletion events")
    async def project_deleted(self, info: Info) -> AsyncGenerator[strawberry.ID, None]:
        user = info.context.user
        if not user or not user.is_authenticated:
            raise PermissionError("Authentication required")

        async with pubsub.subscribe("project_deleted") as subscriber:
            async for payload in subscriber:
                project_id = await _extract_id(payload)
                yield strawberry.ID(project_id)