"""阈值提醒状态机：低于阈值提醒一次，恢复后重新武装。

状态（accounts.alert_armed）：
- 1 = 已武装，低于阈值时可提醒
- 0 = 已提醒，等待余额恢复到阈值以上
发送成功才切换状态；Telegram 失败则保持原状态，下次检查再试。
"""

from __future__ import annotations

import logging
from datetime import datetime

from app import db
from app.config import Config
from app.telegram import send_message

logger = logging.getLogger("monitor.alert")


def _fmt(v: float | None) -> str:
    return "—" if v is None else f"{v:g}"


def build_alert_message(kind: str, account: dict, platform: dict, balance: float | None) -> str:
    pname = platform["name"]
    aname = account["name"]
    cur = platform["currency"]
    th = account["threshold"]
    now = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
    if kind == "below":
        return (f"⚠️ 余额不足提醒\n"
                f"平台：{pname}\n账号：{aname}\n"
                f"当前余额：{_fmt(balance)} {cur}\n阈值：{_fmt(th)} {cur}\n"
                f"时间：{now}")
    if kind == "recovered":
        return (f"✅ 余额已恢复\n"
                f"平台：{pname}\n账号：{aname}\n"
                f"当前余额：{_fmt(balance)} {cur}\n阈值：{_fmt(th)} {cur}\n"
                f"时间：{now}")
    if kind == "disabled":
        return (f"🚫 账号已自动禁用\n"
                f"平台：{pname}\n账号：{aname}\n"
                f"原因：{account.get('last_error') or '认证失败'}")
    return ""


def evaluate(account: dict, platform: dict, balance: float, cfg: Config) -> None:
    """拉取成功后调用：按状态机决定是否发送提醒，发送成功才更新武装状态。"""
    threshold = account["threshold"]
    armed = bool(account["alert_armed"])
    below = balance < threshold
    if below and armed:
        kind = "below"
        logger.info("触发提醒: %s / %s 余额 %s < 阈值 %s（%s）", platform["name"], account["name"], _fmt(balance), _fmt(threshold), platform["currency"])
    elif not below and not armed:
        kind = "recovered"
        logger.info("余额恢复: %s / %s 余额 %s >= 阈值 %s（%s）", platform["name"], account["name"], _fmt(balance), _fmt(threshold), platform["currency"])
    else:
        return
    message = build_alert_message(kind, account, platform, balance)
    if send_message(cfg.telegram_bot_token, cfg.telegram_chat_id, message):
        new_armed = 0 if kind == "below" else 1
        with db.get_conn() as conn:
            conn.execute("UPDATE accounts SET alert_armed = ? WHERE id = ?", (new_armed, account["id"]))
            conn.execute(
                "INSERT INTO alert_log (account_id, type, message) VALUES (?, ?, ?)",
                (account["id"], kind, message),
            )
        logger.info("已发送%s提醒: account=%s", kind, account["id"])
    else:
        logger.warning("提醒发送失败，保持原状态稍后重试: account=%s kind=%s", account["id"], kind)


def notify_disabled(account: dict, platform: dict, cfg: Config) -> None:
    """认证失败禁用账号后通知用户（不参与状态机）。"""
    message = build_alert_message("disabled", account, platform, None)
    if send_message(cfg.telegram_bot_token, cfg.telegram_chat_id, message):
        with db.get_conn() as conn:
            conn.execute(
                "INSERT INTO alert_log (account_id, type, message) VALUES (?, ?, ?)",
                (account["id"], "disabled", message),
            )