import json
from typing import Any

import httpx
from pydantic import AliasChoices, BaseModel, Field

from app.core.config import settings


class TiandituGeocodeRequest(BaseModel):
    keyword: str = Field(
        ...,
        min_length=1,
        validation_alias=AliasChoices("keyword", "keyWord"),
        description="地理编码地址关键字",
    )


class TiandituGeocodingConfigError(RuntimeError):
    pass


class TiandituGeocodingAPIError(RuntimeError):
    def __init__(self, status_code: int, detail: Any):
        super().__init__("Tianditu Geocoding API request failed")
        self.status_code = status_code
        self.detail = detail


async def geocode_tianditu(
    request: TiandituGeocodeRequest,
    *,
    client: httpx.AsyncClient | None = None,
) -> dict[str, Any]:
    if not settings.TIANDITU_GEOCODER_TOKEN:
        raise TiandituGeocodingConfigError("TIANDITU_GEOCODER_TOKEN is not configured")

    params = {
        "ds": json.dumps({"keyWord": request.keyword}, ensure_ascii=False),
        "tk": settings.TIANDITU_GEOCODER_TOKEN,
    }

    if client is not None:
        response = await client.get(settings.TIANDITU_GEOCODER_URL, params=params)
        return _parse_response(response)

    async with httpx.AsyncClient(
        timeout=settings.TIANDITU_GEOCODER_TIMEOUT_SECONDS
    ) as managed_client:
        response = await managed_client.get(
            settings.TIANDITU_GEOCODER_URL,
            params=params,
        )
        return _parse_response(response)


def _parse_response(response: httpx.Response) -> dict[str, Any]:
    try:
        response.raise_for_status()
    except httpx.HTTPStatusError as exc:
        raise TiandituGeocodingAPIError(
            exc.response.status_code,
            _response_detail(exc.response),
        ) from exc

    data = response.json()
    if str(data.get("status")) != "0":
        raise TiandituGeocodingAPIError(502, data)
    return data


def _response_detail(response: httpx.Response) -> Any:
    try:
        return response.json()
    except ValueError:
        return response.text