"""/me 当前用户信息 + 翻译配额。"""
from __future__ import annotations

from datetime import datetime, timezone

from fastapi import APIRouter, Depends
from pydantic import BaseModel
from sqlalchemy.ext.asyncio import AsyncSession

from app.config import settings
from app.core.deps import get_current_user
from app.database import get_session
from app.models.user import User
from app.redis_client import get_redis

router = APIRouter(prefix="/me", tags=["me"])


class MeOut(BaseModel):
    id: int
    username: str
    email: str | None
    role: str
    display_name: str | None
    created_at: datetime


class UsageOut(BaseModel):
    month: str
    used_chars: int
    quota_chars: int
    remaining_chars: int
    buffered_quota: int
    pct_used: float


@router.get("", response_model=MeOut)
async def me(user: User = Depends(get_current_user)):
    return MeOut(
        id=user.id,
        username=user.username,
        email=user.email,
        role=user.role.value,
        display_name=user.display_name,
        created_at=user.created_at,
    )


@router.get("/usage", response_model=UsageOut)
async def usage(
    user: User = Depends(get_current_user),
    session: AsyncSession = Depends(get_session),  # noqa: ARG001
):
    r = get_redis()
    now = datetime.now(timezone.utc)
    key = f"translation:month:{now:%Y%m}"
    used = int(await r.get(key) or 0)
    quota = settings.tencent_tmt_quota_month
    buffered = int(quota * (1 - settings.tencent_tmt_quota_buffer))
    remaining = max(0, quota - used)
    return UsageOut(
        month=f"{now:%Y%m}",
        used_chars=used,
        quota_chars=quota,
        remaining_chars=remaining,
        buffered_quota=buffered,
        pct_used=round(used / quota * 100, 2) if quota else 0.0,
    )