"""看激励视频观看时长 CRUD(每日总时长防刷)。

前端 onAdClose 上报本次观看秒数 → add_watch_seconds 落库 + 返回当日累计;
watched_seconds_today 给"时长闸"(发奖 / 展示前)判断当天是否已达 50 分钟上限。
鉴权接口已确保 user 存在(JWT),故不做 UnknownUser 校验。
"""
from __future__ import annotations

from sqlalchemy import func, select
from sqlalchemy.orm import Session

from app.core.rewards import MAX_SINGLE_WATCH_SECONDS, cn_today
from app.models.ad_watch_log import AdWatchLog


def watched_seconds_today(db: Session, user_id: int, *, today: str | None = None) -> int:
    """该用户今日(北京时间)累计观看秒数。coalesce 防无记录时 SUM 返 None。"""
    d = today or cn_today().isoformat()
    return db.execute(
        select(func.coalesce(func.sum(AdWatchLog.watch_seconds), 0)).where(
            AdWatchLog.user_id == user_id,
            AdWatchLog.watch_date == d,
        )
    ).scalar_one()


def add_watch_seconds(db: Session, user_id: int, seconds: int) -> int:
    """记一次观看时长,返回当日累计秒数。

    seconds 夹 [0, MAX_SINGLE_WATCH_SECONDS] 防前端报异常大值(刷时长无意义,但夹紧更稳)。
    """
    clamped = max(0, min(int(seconds), MAX_SINGLE_WATCH_SECONDS))
    today = cn_today().isoformat()
    db.add(AdWatchLog(user_id=user_id, watch_seconds=clamped, watch_date=today))
    db.commit()
    return watched_seconds_today(db, user_id, today=today)