"""Feishu/Lark 告警发送"""

from __future__ import annotations

import hashlib
import logging
from datetime import datetime
from zoneinfo import ZoneInfo

import httpx

from app.config import settings
from app.data.cache import cache

logger = logging.getLogger(__name__)


def _build_signature(
    source: str,
    message: str,
    level: str,
    context: dict | None = None,
) -> str:
    context = context or {}
    basis = "|".join([
        source,
        level,
        message.strip(),
        str(context.get("method", "")),
        str(context.get("path", "")),
    ])
    return hashlib.sha1(basis.encode("utf-8")).hexdigest()


def _truncate(text: str, limit: int) -> str:
    text = (text or "").strip()
    if len(text) <= limit:
        return text
    return f"{text[:limit]}..."


async def send_feishu_alert(
    source: str,
    message: str,
    detail: str = "",
    level: str = "error",
    context: dict | None = None,
) -> bool:
    """发送 Feishu 告警，内置去重，失败不抛异常。"""
    if not settings.alert_enabled or not settings.feishu_webhook_url:
        return False

    signature = _build_signature(source, message, level, context)
    dedup_key = f"feishu_alert:{signature}"
    if cache.get(dedup_key):
        return False

    cache.set(dedup_key, True, settings.alert_dedup_ttl_seconds)
    now = datetime.now(ZoneInfo("Asia/Shanghai")).strftime("%Y-%m-%d %H:%M:%S")
    context = context or {}
    detail = _truncate(detail, settings.alert_max_detail_chars)

    lines = [
        f"[{settings.alert_app_name}] {level.upper()}",
        f"环境: {settings.alert_environment}",
        f"时间: {now}",
        f"来源: {source}",
        f"摘要: {message}",
    ]
    if context.get("method") or context.get("path"):
        lines.append(
            f"请求: {context.get('method', '')} {context.get('path', '')}".strip()
        )
    if context.get("query"):
        lines.append(f"Query: {context['query']}")
    if detail:
        lines.append(f"详情: {detail}")

    payload = {
        "msg_type": "text",
        "content": {
            "text": "\n".join(lines),
        },
    }

    try:
        async with httpx.AsyncClient(timeout=8, follow_redirects=True) as client:
            resp = await client.post(settings.feishu_webhook_url, json=payload)
            resp.raise_for_status()
        return True
    except Exception as e:
        logger.warning("Feishu 告警发送失败: %s", e)
        return False