from __future__ import annotations

from typing import TYPE_CHECKING, Any, Protocol, TypeVar

from ag_ui.core import BaseEvent

if TYPE_CHECKING:
    pass

T = TypeVar("T", bound=BaseEvent)


class CodecLike(Protocol):
    def to_wire(self, event: dict[str, Any]) -> dict[str, Any]: ...


class StoreLike(Protocol):
    async def persist(self, event: dict[str, Any]) -> None: ...


class BusLike(Protocol):
    async def publish(self, *, session_id: str, event: dict[str, Any]) -> str: ...


def is_base_event(event: Any) -> bool:
    return isinstance(event, BaseEvent)


def to_dict(event: BaseEvent | dict[str, Any]) -> dict[str, Any]:
    if isinstance(event, BaseEvent):
        return event.model_dump(by_alias=True, exclude_none=True)
    return event


class AgentScopeEventPipeline:
    _codec: CodecLike
    _store: StoreLike
    _bus: BusLike

    def __init__(self, *, codec: CodecLike, store: StoreLike, bus: BusLike) -> None:
        self._codec = codec
        self._store = store
        self._bus = bus

    async def emit(
        self,
        *,
        session_id: str,
        event: "BaseEvent | dict[str, Any]",
    ) -> str:
        event_dict = to_dict(event)
        wire_event = self._codec.to_wire(event_dict)
        await self._store.persist(event_dict)
        return await self._bus.publish(session_id=session_id, event=wire_event)