from datetime import datetime, timedelta, timezone
from zoneinfo import ZoneInfo
from app.db.database import users_collection, db

coins_sessions_collection = db.coins_sessions

TZ = ZoneInfo("Asia/Yekaterinburg")

def _day_bounds_utc(now_utc: datetime):
    now_local = now_utc.astimezone(TZ)
    start_local = now_local.replace(hour=0, minute=0, second=0, microsecond=0)
    start_utc = start_local.astimezone(timezone.utc)
    next_utc = (start_local + timedelta(days=1)).astimezone(timezone.utc)
    return now_local.date(), start_utc, next_utc, start_local

class DailyRewardService:
    async def claim_daily(self, username: str) -> dict:
        now_utc = datetime.now(timezone.utc)
        today_local, start_today_utc, start_tomorrow_utc, _ = _day_bounds_utc(now_utc)

        user = await users_collection.find_one({"username": username})
        if not user:
            return {"claimed": False, "reason": "user_not_found"}
        
        was_online_today = await coins_sessions_collection.find_one(
            {
                "player_name": username,
                "update_type": "coins_update",
                "timestamp": {
                    "$gte": start_today_utc.replace(tzinfo=None),
                    "$lt": start_tomorrow_utc.replace(tzinfo=None),
                },
            }
        )

        if not was_online_today:
            return {
                "claimed": False,
                "reason": "not_online_today",
                "message": "Вы должны зайти на сервер сегодня, чтобы получить ежедневную награду",
            }

        last_claim_at = user.get("daily_last_claim_at")  # ожидаем datetime (лучше хранить UTC)
        last_local_day = last_claim_at.replace(tzinfo=timezone.utc).astimezone(TZ).date() if last_claim_at else None

        if last_local_day == today_local:
            return {"claimed": False, "reason": "already_claimed_today", "streak": user.get("daily_streak", 0)}

        yesterday_local = today_local - timedelta(days=1)
        prev_streak = int(user.get("daily_streak", 0) or 0)
        new_streak = (prev_streak + 1) if (last_local_day == yesterday_local) else 1

        # твоя новая формула: 10, 20, 30 ... до 50 (кап)
        reward = min(10 + (new_streak - 1) * 10, 50)

        result = await users_collection.update_one(
            {
                "username": username,
                "$or": [
                    {"daily_last_claim_at": {"$exists": False}},
                    {"daily_last_claim_at": {"$lt": start_today_utc.replace(tzinfo=None)}},
                ],
            },
            {
                "$inc": {"coins": reward},
                "$set": {"daily_last_claim_at": now_utc.replace(tzinfo=None), "daily_streak": new_streak},
            },
        )

        if result.modified_count == 0:
            user2 = await users_collection.find_one({"username": username})
            return {"claimed": False, "reason": "already_claimed_today", "streak": user2.get("daily_streak", 0)}

        await coins_sessions_collection.insert_one({
            "player_name": username,
            "update_type": "daily_login",
            "timestamp": now_utc.replace(tzinfo=None),
            "coins_added": reward,
            "streak": new_streak,
        })

        return {"claimed": True, "coins_added": reward, "streak": new_streak}

    async def get_status(self, username: str) -> dict:
        now_utc = datetime.now(timezone.utc)
        today_local, start_today_utc, start_tomorrow_utc, start_today_local = _day_bounds_utc(now_utc)

        user = await users_collection.find_one({"username": username})
        if not user:
            return {"ok": False, "reason": "user_not_found"}

        was_online_today = await coins_sessions_collection.find_one({
            "player_name": username,
            "update_type": "coins_update",
            "timestamp": {
                "$gte": start_today_utc.replace(tzinfo=None),
                "$lt": start_tomorrow_utc.replace(tzinfo=None),
            },
        })

        last_claim_at = user.get("daily_last_claim_at")
        last_local_day = last_claim_at.replace(tzinfo=timezone.utc).astimezone(TZ).date() if last_claim_at else None

        can_claim = (last_local_day != today_local) and bool(was_online_today)

        seconds_to_next = 0 if can_claim else int((start_tomorrow_utc - now_utc).total_seconds())
        if seconds_to_next < 0:
            seconds_to_next = 0

        return {
            "ok": True,
            "can_claim": can_claim,
            "was_online_today": bool(was_online_today),
            "seconds_to_next": seconds_to_next,
            "next_claim_at_utc": start_tomorrow_utc.isoformat().replace("+00:00", "Z"),
            "next_claim_at_local": (start_today_local + timedelta(days=1)).isoformat(),
            "streak": int(user.get("daily_streak", 0) or 0),
        }
        
    async def get_claim_days(self, username: str, limit: int = 60) -> dict:
        # Берём последние N записей daily_login и превращаем в список уникальных дней по ЕКБ
        cursor = coins_sessions_collection.find(
            {"player_name": username, "update_type": "daily_login"},
            {"timestamp": 1, "_id": 0},
        ).sort("timestamp", -1).limit(limit)

        days = []
        seen = set()

        async for doc in cursor:
            ts = doc.get("timestamp")
            if not ts:
                continue

            # У тебя timestamp в Mongo — naive UTC (now_utc.replace(tzinfo=None)) :contentReference[oaicite:1]{index=1}
            ts_utc = ts.replace(tzinfo=timezone.utc)
            day_local = ts_utc.astimezone(TZ).date().isoformat()  # YYYY-MM-DD по ЕКБ

            if day_local not in seen:
                seen.add(day_local)
                days.append(day_local)

        days.reverse()  # чтобы было по возрастанию (старые → новые), если надо
        return {"ok": True, "days": days, "count": len(days)}