from __future__ import annotations

import time

import httpx
import markdown2

from app.config import settings
from app.schemas import PublishResponse, WechatPublishRequest


class WechatPublisher:
    def __init__(self) -> None:
        self._access_token = None
        self._expires_at = 0

    async def publish_draft(self, req: WechatPublishRequest) -> PublishResponse:
        if not settings.wechat_appid or not settings.wechat_secret:
            return PublishResponse(ok=False, detail="缺少 WECHAT_APPID / WECHAT_SECRET 配置")

        token = await self._get_access_token()
        if not token:
            return PublishResponse(ok=False, detail="获取微信 access_token 失败")

        html = markdown2.markdown(req.body_markdown)
        payload = {
            "articles": [
                {
                    "title": req.title,
                    "author": req.author or settings.wechat_author,
                    "digest": req.summary,
                    "content": html,
                    "content_source_url": "",
                    "need_open_comment": 0,
                    "only_fans_can_comment": 0,
                }
            ]
        }

        async with httpx.AsyncClient(timeout=25) as client:
            url = f"https://api.weixin.qq.com/cgi-bin/draft/add?access_token={token}"
            r = await client.post(url, json=payload)
            data = r.json()

        if data.get("errcode", 0) != 0:
            return PublishResponse(ok=False, detail=f"微信发布失败: {data}", data=data)

        return PublishResponse(ok=True, detail="已发布到公众号草稿箱", data=data)

    async def _get_access_token(self) -> str | None:
        now = int(time.time())
        if self._access_token and now < self._expires_at - 60:
            return self._access_token

        async with httpx.AsyncClient(timeout=20) as client:
            r = await client.get(
                "https://api.weixin.qq.com/cgi-bin/token",
                params={
                    "grant_type": "client_credential",
                    "appid": settings.wechat_appid,
                    "secret": settings.wechat_secret,
                },
            )
            data = r.json()

        token = data.get("access_token")
        if not token:
            return None

        self._access_token = token
        self._expires_at = now + int(data.get("expires_in", 7200))
        return token