package com.dsh.utils;

import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author: lihong .
 * @email: lihongvst@foxmail.com .
 * @createTime: 2019/6/27 9:32  .
 * @describe: servlet工具.
 **/
public final class ServletUtils {

    /**
     * 获取请求对象.
     * @return
     */
    public static HttpServletRequest getHttpServletRequest(){
        HttpServletRequest request = getReqyuestAttributes().getRequest();
        return request;
    }

    /**
     * 获取响应对象.
     * @return
     */
    public static HttpServletResponse getHttpServletResponse(){
        HttpServletResponse response = getReqyuestAttributes().getResponse();
        return response;
    }

    /**
     * 获取请求参数.
     * @return
     */
    private static ServletRequestAttributes getReqyuestAttributes(){
        ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        return requestAttributes;
    }

    /**
     * 获取真实ip
     * @return
     */
    public static String getIpAddr() {
        HttpServletRequest request = getHttpServletRequest();
        String ip = request.getHeader("x-forwarded-for");
        System.out.println("x-forwarded-for ip: " + ip);
        if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) {
            // 多次反向代理后会有多个ip值，第一个ip才是真实ip
            if( ip.indexOf(",")!=-1 ){
                ip = ip.split(",")[0];
            }
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_CLIENT_IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_X_FORWARDED_FOR");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("X-Real-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        return ip;
    }

}