"""FastAPI test app that registers the AFI fixture."""

from __future__ import annotations

from fastapi import FastAPI

from mizan_fastapi import (
    Channel,
    MizanError,
    mizan_exception_handler,
    mizan_validation_handler,
    register_channel,
    router as mizan_router,
)

from fixture import (
    CHAT_CHANNEL,
    USER_ALERTS_CHANNEL,
    ChatClientMessage,
    ChatParams,
    ChatServerMessage,
    UserAlertsServerMessage,
    register_fixture,
)


class ChatChannel(Channel):
    """All three slots declared; the room keys the fan-out."""

    Params = ChatParams
    ClientMessage = ChatClientMessage
    ServerMessage = ChatServerMessage

    def group(self, params: ChatParams | None = None) -> str:
        return f"chat:{params.room_id}" if params else "chat"


class UserAlertsChannel(Channel):
    """Push-only: no params, nothing travels up."""

    ServerMessage = UserAlertsServerMessage


def make_app() -> FastAPI:
    """Build a fresh FastAPI app with the AFI fixture registered."""
    register_fixture()
    register_channel(ChatChannel, CHAT_CHANNEL)
    register_channel(UserAlertsChannel, USER_ALERTS_CHANNEL)

    app = FastAPI()
    app.include_router(mizan_router, prefix="/api/mizan")
    app.add_exception_handler(MizanError, mizan_exception_handler)
    from fastapi.exceptions import RequestValidationError
    app.add_exception_handler(RequestValidationError, mizan_validation_handler)
    return app