"""Usage service: fully proxied to sub2api (user JWT for user-scoped endpoints)."""
from __future__ import annotations

from typing import Any

from fastapi import HTTPException
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.exceptions import BadRequestError
from app.integrations.sub2api import user as sub2api_user
from app.integrations.sub2api.client import (
    Sub2APIError,
    Sub2APIReauthRequired,
    Sub2APITransportError,
)
from app.models import User
from app.services.sub2api_session import ensure_access_token


def _require_binding(user: User) -> int:
    if not user.sub2api_user_id:
        raise BadRequestError("账号未完成 sub2api 绑定，请重新登录")
    return user.sub2api_user_id


def _translate(exc: Exception) -> HTTPException:
    if isinstance(exc, Sub2APIReauthRequired):
        return HTTPException(status_code=401, detail="sub2api_reauth_required")
    if isinstance(exc, Sub2APIError):
        status = exc.http_status or 502
        if status < 400 or status >= 600:
            status = 502
        return HTTPException(status_code=status, detail=exc.message or exc.reason or "upstream_error")
    return HTTPException(status_code=504, detail="upstream_timeout")


class UsageService:
    @staticmethod
    async def list_logs(db: AsyncSession, user: User, **params: Any) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.list_usage(token, **params)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc

    @staticmethod
    async def stats(db: AsyncSession, user: User, **params: Any) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.usage_stats(token, **params)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc

    @staticmethod
    async def dashboard_stats(db: AsyncSession, user: User) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.dashboard_stats(token)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc

    @staticmethod
    async def dashboard_trend(db: AsyncSession, user: User, **params: Any) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.dashboard_trend(token, **params)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc

    @staticmethod
    async def dashboard_models(db: AsyncSession, user: User, **params: Any) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.dashboard_models(token, **params)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc

    @staticmethod
    async def dashboard_api_keys_usage(
        db: AsyncSession, user: User, api_key_ids: list[int]
    ) -> dict[str, Any]:
        _require_binding(user)
        try:
            token = await ensure_access_token(db, user)
            return await sub2api_user.dashboard_api_keys_usage(token, api_key_ids)
        except (Sub2APIError, Sub2APITransportError) as exc:
            raise _translate(exc) from exc