dingdanquanliucheng/backend/app/services/wechat_notification_service.py

import json
import time
from urllib import error, request

from sqlalchemy.orm import Session

from backend.app.core.config import get_settings
from backend.app.core.error_codes import ErrorCode
from backend.app.core.exceptions import AppException


class WeChatNotificationService:
    """微信小程序订阅消息通知服务。

    通过微信 subscribeMessage.send 接口向用户推送服务提醒。
    需要在小程序后台配置消息模板，并将模板 ID 填入系统配置。
    """

    TOKEN_CACHE: dict[str, str] = {"token": "", "expires_at": 0}

    REMINDER_TYPE_TEMPLATE_MAP: dict[str, str] = {
        "order_status_change": "wechat_template_order_status",
        "order_approval_needed": "wechat_template_approval",
        "task_assigned": "wechat_template_task_assigned",
        "logistics_timeout": "wechat_template_logistics_timeout",
        "arrears": "wechat_template_arrears",
        "inactive_customer": "wechat_template_inactive_customer",
    }

    # 每个模板的微信字段名映射
    # 格式: reminder_type -> { "微信模板字段名": "extra_data 中的 key" }
    TEMPLATE_FIELD_MAP: dict[str, dict[str, str]] = {
        "order_status_change": {
            "phrase3": "status_text",
            "time5": "change_time",
            "character_string6": "order_no",
            "thing4": "remark",
            "thing18": "goods_info",
        },
        "order_approval_needed": {
            "thing18": "submitter",
            "thing16": "task_name",
            "time20": "submit_time",
            "thing10": "remark",
        },
        "task_assigned": {
            "time2": "assign_time",
            "thing7": "task_name",
            "time9": "publish_time",
            "time11": "start_time",
        },
        "logistics_timeout": {
            "phrase1": "order_status",
            "date2": "deadline",
            "thing3": "remark",
            "character_string4": "order_no",
        },
        "arrears": {
            "thing5": "order_detail",
            "date6": "order_time",
            "time10": "appointment_time",
            "amount12": "pending_amount",
            "character_string4": "order_no",
        },
        "inactive_customer": {
            "thing1": "activity_name",
            "time2": "activity_time",
            "thing3": "location",
            "thing4": "remark",
        },
    }

    def send_subscribe_message(self, open_id: str, reminder_type: str, title: str = "", content: str = "", extra_data: dict | None = None, biz_url: str = "") -> bool:
        settings = get_settings()
        if not settings.wechat_app_id or not settings.wechat_app_secret:
            return False

        template_id = self._get_template_id(settings, reminder_type)
        if not template_id:
            return False

        access_token = self._get_access_token(settings)
        if not access_token:
            return False

        field_map = self.TEMPLATE_FIELD_MAP.get(reminder_type)
        if not field_map:
            return False

        data = extra_data or {}
        now_str = time.strftime("%Y-%m-%d %H:%M")
        payload_data = {}
        for wx_field, data_key in field_map.items():
            value = data.get(data_key, "")
            if not value:
                value = title if data_key == "order_no" else now_str
            payload_data[wx_field] = {"value": str(value)[:100]}

        payload = {
            "touser": open_id,
            "template_id": template_id,
            "page": biz_url,
            "data": payload_data,
        }

        url = f"https://api.weixin.qq.com/cgi-bin/message/subscribe/send?access_token={access_token}"
        req = request.Request(
            url=url,
            data=json.dumps(payload, ensure_ascii=False).encode("utf-8"),
            headers={"Content-Type": "application/json; charset=UTF-8"},
            method="POST",
        )
        try:
            with request.urlopen(req, timeout=10) as response:
                result = json.loads(response.read().decode("utf-8") or "{}")
                return result.get("errcode", -1) == 0
        except (error.HTTPError, error.URLError, json.JSONDecodeError):
            return False

    async def send_reminder(self, open_id: str, reminder_type: str, data: dict | None = None) -> bool:
        """发送提醒消息（兼容 event_bus 调用）

        Args:
            open_id: 用户的微信 open_id
            reminder_type: 提醒类型
            data: 额外数据

        Returns:
            是否发送成功
        """
        extra_data = {}
        if data:
            # 从 event_bus 传递的数据中提取模板字段所需的数据
            extra_data = {
                "order_no": data.get("order_no", ""),
                "status_text": data.get("status_desc", data.get("status", "")),
                "change_time": data.get("change_time", time.strftime("%Y-%m-%d %H:%M")),
                "remark": data.get("remark", data.get("content", "")),
                "goods_info": data.get("goods_info", ""),
                "submitter": data.get("salesman_name", data.get("submitter", "")),
                "task_name": data.get("task_no", data.get("task_name", "")),
                "submit_time": data.get("submit_time", time.strftime("%Y-%m-%d %H:%M")),
                "assign_time": data.get("assign_time", time.strftime("%Y-%m-%d %H:%M")),
                "publish_time": data.get("publish_time", time.strftime("%Y-%m-%d %H:%M")),
                "start_time": data.get("start_time", time.strftime("%Y-%m-%d %H:%M")),
                "order_status": data.get("status_desc", data.get("status", "")),
                "deadline": data.get("deadline", ""),
                "order_detail": data.get("order_detail", data.get("content", "")),
                "order_time": data.get("order_time", ""),
                "appointment_time": data.get("appointment_time", ""),
                "pending_amount": data.get("amount", ""),
                "activity_name": data.get("customer_name", ""),
                "activity_time": data.get("activity_time", time.strftime("%Y-%m-%d %H:%M")),
                "location": data.get("location", ""),
            }

        title = data.get("title", "") if data else ""
        content = data.get("content", "") if data else ""
        biz_url = data.get("biz_url", "") if data else ""

        return self.send_subscribe_message(
            open_id=open_id,
            reminder_type=reminder_type,
            title=title,
            content=content,
            extra_data=extra_data,
            biz_url=biz_url
        )

    def bind_open_id(self, session: Session, user_id: int, open_id: str) -> None:
        from backend.app.models.system import User
        from sqlalchemy import select
        user = session.execute(select(User).where(User.id == user_id)).scalar_one_or_none()
        if user is not None:
            user.open_id = open_id
            session.add(user)
            session.commit()

    def _get_template_id(self, settings, reminder_type: str) -> str:
        config_key = self.REMINDER_TYPE_TEMPLATE_MAP.get(reminder_type, "")
        if not config_key:
            return ""
        return getattr(settings, config_key, "")

    def _get_access_token(self, settings) -> str:
        now = time.time()
        if self.TOKEN_CACHE["token"] and self.TOKEN_CACHE["expires_at"] > now + 60:
            return self.TOKEN_CACHE["token"]

        url = (
            f"https://api.weixin.qq.com/cgi-bin/token"
            f"?grant_type=client_credential"
            f"&appid={settings.wechat_app_id}"
            f"&secret={settings.wechat_app_secret}"
        )
        req = request.Request(url=url, method="GET")
        try:
            with request.urlopen(req, timeout=10) as response:
                result = json.loads(response.read().decode("utf-8") or "{}")
                token = result.get("access_token", "")
                expires_in = int(result.get("expires_in", 0))
                if token and expires_in > 0:
                    self.TOKEN_CACHE["token"] = token
                    self.TOKEN_CACHE["expires_at"] = now + expires_in
                    return token
        except (error.HTTPError, error.URLError, json.JSONDecodeError):
            pass
        return ""


wechat_notification_service = WeChatNotificationService()