from __future__ import annotations
from datetime import date, timedelta

from services.db.mysql_service import DatabaseService


class ReminderRepository:
    """td_reminders 테이블을 통한 알림 저장소."""

    def __init__(self, db: DatabaseService):
        self._db = db

    def add(self, user_id: str, remind_date: date, message: str) -> int:
        return self._db.execute_write(
            "INSERT INTO td_reminders (user_id, remind_date, message) VALUES (%s, %s, %s)",
            (user_id, remind_date.isoformat(), message),
        )

    def get_upcoming(self, user_id: str, days_ahead: int = 30) -> list[dict]:
        today = date.today()
        limit = today + timedelta(days=days_ahead)
        return self._db.execute(
            """SELECT id, remind_date, message
               FROM td_reminders
               WHERE user_id = %s AND remind_date >= %s AND remind_date <= %s
               ORDER BY remind_date""",
            (user_id, today.isoformat(), limit.isoformat()),
        )

    def get_due(self, today: date) -> list[dict]:
        """D-0(당일), D-1(내일), D-7(7일 후) 미발송 알림 반환."""
        d1 = today + timedelta(days=1)
        d7 = today + timedelta(days=7)
        return self._db.execute(
            """SELECT *,
                CASE
                    WHEN remind_date = %s THEN 'd0'
                    WHEN remind_date = %s THEN 'd1'
                    WHEN remind_date = %s THEN 'd7'
                END AS notify_type
               FROM td_reminders
               WHERE (remind_date = %s AND sent_d0 = 0)
                  OR (remind_date = %s AND sent_d1 = 0)
                  OR (remind_date = %s AND sent_d7 = 0)""",
            (
                today.isoformat(), d1.isoformat(), d7.isoformat(),
                today.isoformat(), d1.isoformat(), d7.isoformat(),
            ),
        )

    def mark_sent(self, reminder_id: int, notify_type: str) -> None:
        col = {"d0": "sent_d0", "d1": "sent_d1", "d7": "sent_d7"}.get(notify_type)
        if col:
            self._db.execute_write(
                f"UPDATE td_reminders SET {col} = 1 WHERE id = %s",
                (reminder_id,),
            )