package com.supervision.config;

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONObject;
import cn.hutool.json.JSONUtil;
import cn.hutool.jwt.JWT;
import cn.hutool.jwt.JWTUtil;
import com.supervision.exception.BusinessException;
import com.supervision.util.TokenUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.HttpStatus;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;

@Slf4j
public class JwtInterceptor implements HandlerInterceptor {



    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        //请求消息头获取用户ID
        String token = request.getHeader("token");
        if (StrUtil.isBlank(token)) {
            // 如果是swagger来的接口,说明这里是测试的,会伪造一个用户
            if (StrUtil.isNotBlank(request.getHeader("Knife4j-Gateway-Code"))) {
                cacheAuth(JWTUtil.parseToken(devActiveUser()));
                return true;
            } else {
                throw new BusinessException("当前用户未登录", HttpStatus.UNAUTHORIZED.value());
            }
        }

        JWT jwt = JWTUtil.parseToken(token);
        // 校验token是否过期,如果过期了,需要提示过期重新登录
        checkTokenExpire(jwt);
        // 校验是否重复登录
        UserSingleLoginConfig.checkSingleLogin(jwt);
        cacheAuth(jwt);
        return true;
    }


    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        // 请求结束,将用户信息从thread中移除
        clearAuth();
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }


    private void checkTokenExpire(JWT jwt) {
        Object expireTime = jwt.getPayload("expireTime");
        long l = Long.parseLong(String.valueOf(expireTime));
        // 校验是否比当前时间大
        long currentTimeMillis = System.currentTimeMillis();
        if (currentTimeMillis > l) {
            throw new BusinessException("用户登录已过期,请重新登录", HttpStatus.UNAUTHORIZED.value());
        }
    }



    private void cacheAuth(JWT jwt) {
        try {
            JSONObject claimsJson = jwt.getPayload().getClaimsJson();
            ThreadCache.USER.set(claimsJson.toString());
        } catch (Exception e) {
            log.error("用户信息异常", e);
        }
    }

    private String devActiveUser() {
        Map<String, Object> map = new HashMap<>();
        map.put("id", "1");
        map.put("account", "test");
        map.put("name", "测试账户");
        return TokenUtil.creatToken(JSONUtil.toJsonStr(map));
    }

    private void clearAuth() {
        ThreadCache.USER.remove();
    }
}