package com.example.mini_program.service;

import com.example.mini_program.config.WxMiniAppConfig;
import com.example.mini_program.util.HttpUtil;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import java.util.HashMap;
import java.util.Map;

/**
 * 微信小程序订阅消息服务
 * 调用微信 /cgi-bin/message/subscribe/send 接口推送订阅消息
 * <p>
 * 模板字段映射：
 * name1    (姓名)   → 访客姓名
 * thing3   (事物)   → 来访事由
 * date8    (日期)   → 预约时间
 * thing10  (事物)   → 到访区域
 * phrase18 (短语)   → 审批状态
 */
@Slf4j
@Service
@RequiredArgsConstructor
public class WxSubscribeMessageService {

    private static final String GET_TOKEN_URL =
            "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=%s&secret=%s";
    private static final String SEND_MSG_URL =
            "https://api.weixin.qq.com/cgi-bin/message/subscribe/send?access_token=%s";

    private final WxMiniAppConfig wxMiniAppConfig;
    private final ObjectMapper objectMapper;

    @Value("${wx.miniapp.subscribe-template-id:}")
    private String templateId;

    /**
     * 获取小程序 access_token
     */
    public String getAccessToken() {
        String url = String.format(GET_TOKEN_URL, wxMiniAppConfig.getAppid(), wxMiniAppConfig.getSecret());
        try {
            Map<String, Object> resp = objectMapper.readValue(HttpUtil.get(url), Map.class);
            if (resp.containsKey("access_token")) {
                return (String) resp.get("access_token");
            }
            throw new RuntimeException("获取access_token失败: " + resp);
        } catch (Exception e) {
            throw new RuntimeException("获取access_token异常: " + e.getMessage(), e);
        }
    }

    /**
     * 发送订阅消息
     * 所有字段不允许为空字符串（微信返回47003），name类型不接受纯数字
     */
    public void sendSubscribeMessage(String openid, String visitorName, String reason,
                                     String visitTime, String area, String status) {
        if (templateId == null || templateId.isEmpty()) {
            log.warn("未配置 subscribe-template-id，跳过订阅消息推送");
            return;
        }
        String accessToken = getAccessToken();
        String url = String.format(SEND_MSG_URL, accessToken);

        // name1 是 name 类型，纯数字会被微信拒绝，需加前缀兜底
        String safeName = blankToDefault(visitorName, "访客");
        if (safeName.matches("^\\d+$")) {
            safeName = "访客" + safeName;
        }

        Map<String, Object> data = new HashMap<>();
        data.put("name1", Map.of("value", safeName));
        data.put("thing3", Map.of("value", blankToDefault(reason, "来访")));
        data.put("date8", Map.of("value", blankToDefault(visitTime, "待定")));
        data.put("thing10", Map.of("value", blankToDefault(area, "未指定")));
        data.put("phrase18", Map.of("value", blankToDefault(status, "待审核")));

        Map<String, Object> body = new HashMap<>();
        body.put("touser", openid);
        body.put("template_id", templateId);
        //点击模板卡片后的跳转页面，仅限本小程序内的页面。
        body.put("page", "pages/records/records");
        body.put("data", data);
        //跳转小程序类型：developer为开发版；trial为体验版；formal为正式版；默认为正式版
        body.put("miniprogram_state", "formal");
        body.put("lang", "zh_CN");

        try {
            String json = objectMapper.writeValueAsString(body);
            Map<String, Object> resp = objectMapper.readValue(HttpUtil.postJson(url, json), Map.class);
            if ("0".equals(String.valueOf(resp.get("errcode")))) {
                log.info("订阅消息推送成功, openid={}", openid);
            } else {
                log.error("订阅消息推送失败: {}", resp);
            }
        } catch (Exception e) {
            log.error("订阅消息推送异常", e);
        }
    }

    private static String blankToDefault(String val, String def) {
        return (val != null && !val.isEmpty()) ? val : def;
    }
}