import sqlite3
from datetime import timedelta
from typing import Optional

from flask import abort, session

from .core import isoformat, parse_datetime, utcnow
from .db import execute, fetch_one


def current_user() -> Optional[sqlite3.Row]:
    user_id = session.get("user_id")
    if not user_id:
        return None
    return fetch_one("SELECT * FROM users WHERE id = ?", (user_id,))


def current_admin() -> Optional[sqlite3.Row]:
    admin_id = session.get("admin_user_id")
    if not admin_id:
        return None
    return fetch_one("SELECT * FROM admin_users WHERE id = ?", (admin_id,))


def require_user() -> sqlite3.Row:
    user = current_user()
    if user is None:
        abort(401)
    if user["status"] != "ACTIVE":
        abort(403)
    return user


def require_admin() -> sqlite3.Row:
    admin = current_admin()
    if admin is None:
        abort(401)
    if admin["status"] != "ACTIVE":
        abort(403)
    return admin


def is_vip_active(user: sqlite3.Row) -> bool:
    vip_expire_at = parse_datetime(user["vip_expire_at"])
    return vip_expire_at is not None and vip_expire_at > utcnow()


def extend_vip(user_id: int, duration_days: int) -> None:
    user = fetch_one("SELECT vip_expire_at FROM users WHERE id = ?", (user_id,))
    if user is None:
        abort(404)
    now = utcnow()
    current = parse_datetime(user["vip_expire_at"])
    start = current if (current is not None and current > now) else now
    new_expire = start + timedelta(days=duration_days)
    execute("UPDATE users SET vip_expire_at = ? WHERE id = ?", (isoformat(new_expire), user_id))