/**
 * The MIT License (MIT) * Copyright (c) 2020 铭软科技(mingsoft.net)

 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:

 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package net.mingsoft.basic.util;

import java.util.Enumeration;
import java.util.Map;

import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;

import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;

import com.alibaba.fastjson.JSONObject;

/**
 * basic模块，spring RestTemplate工具类
 * @author 铭飞开发团队
 * @version 
 * 版本号：100-000-000<br/>
 * 创建日期：2017年9月5日<br/>
 * 历史修订：<br/>
 */
public class RestTemplateUtil {
    
    private static RestTemplate restTemplate = new RestTemplate();
    
    /**
     * post请求，保存
     * @param req ServletRequest对象
     * @param url 请求地址
     * @param params 参数
     * @return 内容
     */
    public static String post(ServletRequest req, String url, Map<String, ?> params) {
        ResponseEntity<String> rss = request(req, url, HttpMethod.POST, params);
        return rss.getBody();
    }

    /**
     * get请求,查询
     * @param req ServletRequest对象
     * @param url 请求地址
     * @param params 参数
     * @return
     */
    public static String get(ServletRequest req, String url, Map<String, ?> params) {
        ResponseEntity<String> rss = request(req, url, HttpMethod.GET, params);
        return rss.getBody();
    }
    
    /**
     * 删除
     * @param req
     * @param url
     * @param params
     * @return
     */
    public static String delete(ServletRequest req, String url, Map<String, ?> params) {
        ResponseEntity<String> rss = request(req, url, HttpMethod.DELETE, params);
        return rss.getBody();
    }
    
    /**
     * 保存
     * @param req
     * @param url
     * @param params
     * @return
     */
    public static String put(ServletRequest req, String url, Map<String, ?> params) {
        ResponseEntity<String> rss = request(req, url, HttpMethod.PUT, params);
        return rss.getBody();
    }
    
    /**
     * 请求方法
     * @param req ServletRequest对象
     * @param url 请求地址
     * @param method 方法
     * @param params 参数
     * @return
     */
    private static ResponseEntity<String> request(ServletRequest req, String url, HttpMethod method, Map<String, ?> params) {
        HttpServletRequest request = (HttpServletRequest) req;
        //获取header信息
        HttpHeaders requestHeaders = new HttpHeaders();
        Enumeration<String> headerNames = request.getHeaderNames();
        while (headerNames.hasMoreElements()) {
          String key = (String) headerNames.nextElement();
          String value = request.getHeader(key);
          requestHeaders.add(key, value);
        }
        HttpEntity<String> requestEntity = new HttpEntity<String>(params != null ? JSONObject.toJSONString(params) : null, requestHeaders);
        ResponseEntity<String> rss = restTemplate.exchange(url, method, requestEntity, String.class);
        return rss;
    }
}