import json
from dataclasses import dataclass
from typing import Any


@dataclass
class _FakeRequestState:
    channel_config: dict
    channel_raw_body: dict | None


class FakeRequest:
    """为 Polling / WebSocket 等传输层消息构造的伪请求对象。

    提供 ``request.json()`` 与 ``request.body()`` 接口，并携带 ``state.channel_config``、
    ``state.channel_raw_body``，供 ``normalize_inbound`` 在异步传输消息场景中复用。
    """

    def __init__(
        self,
        config: dict,
        body: dict,
        channel_raw_body: dict | None = None,
        *,
        headers: dict[str, str] | None = None,
        query_params: dict[str, str] | None = None,
        path_params: dict[str, str] | None = None,
    ) -> None:
        raw = channel_raw_body if channel_raw_body is not None else body
        self.state = _FakeRequestState(channel_config=config, channel_raw_body=raw)
        self._json = body
        self._body = json.dumps(body).encode("utf-8")
        self.headers: dict[str, str] = headers or {}
        self.query_params: dict[str, str] = query_params or {}
        self.path_params: dict[str, str] = path_params or {}

    async def json(self) -> dict[str, Any]:
        return self._json

    async def body(self) -> bytes:
        return self._body