package com.sprucetec.tms.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * HttpInvoker.
 *
 * @author Yinqiang Du
 * @date 2016/8/11
 */
public class HttpInvokerUtils {
    /**
     * 日志.
     */
    private static final Logger LOGGER = LoggerFactory.getLogger(HttpInvokerUtils.class);

    /**
     * 发起http get 请求获取返回结果.
     *
     * @param getURL 请求路径 .
     * @return
     * @throws Exception
     */
    public static void readContentFromGet(String getURL) throws IOException {
        // 拼凑get请求的URL字串，使用URLEncoder.encode对特殊和不可见字符进行编码
        URL getUrl = new URL(getURL);
        // 根据拼凑的URL，打开连接，URL.openConnection函数会根据 URL的类型，
        // 返回不同的URLConnection子类的对象，这里URL是一个http，因此实际返回的是HttpURLConnection
        HttpURLConnection connection = (HttpURLConnection) getUrl
                .openConnection();
        // 进行连接，但是实际上get request要在下一句的 connection.getInputStream()函数中才会真正发到
        // 服务器
        connection.connect();
        // 取得输入流，并使用Reader读取
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                connection.getInputStream()));
        System.out.println(" ============================= ");
        System.out.println(" Contents of get request ");
        System.out.println(" ============================= ");
        String lines;
        while ((lines = reader.readLine()) != null) {
            System.out.println(lines);
        }
        reader.close();
        // 断开连接
        connection.disconnect();
        System.out.println(" ============================= ");
        System.out.println(" Contents of get request ends ");
        System.out.println(" ============================= ");
    }

    /**
     * 发起http post 请求获取返回结果.
     *
     * @param urlStr            请求路径 .
     * @param requestParamsJson json字符串.
     * @return
     * @throws Exception
     */
    public static void sendRequest(String urlStr, String requestParamsJson) throws Exception {
        BufferedOutputStream bufOutPut = null;
        BufferedReader bufferedReader = null;
        HttpURLConnection httpConn = null;
        try {
            URL url = new URL(urlStr);
            httpConn = (HttpURLConnection) url.openConnection();
            httpConn.setDoInput(true); // 设置是否从httpUrlConnection读入，默认情况下是true;
            httpConn.setDoOutput(true);  // 设置是否向httpUrlConnection输出，因为这个是post请求，参数要放在http正文内，因此需要设为true, 默认情况下是false;
            httpConn.setRequestMethod("POST");// 设定请求的方法为"POST"，默认是GET
            httpConn.setAllowUserInteraction(false); //是否允许用户交互
            httpConn.setUseCaches(false);  // Post 请求不能使用缓存
            httpConn.setInstanceFollowRedirects(true);
            httpConn.setRequestProperty("Accept-Charset", "UTF-8");
            httpConn.setRequestProperty("Connection", "Keep-Alive");// 维持长连接
            httpConn.setRequestProperty("Content-Type", "application/json");   // 设定传送的内容类型是可序列化的java对象
            // 此处getOutputStream会隐含的进行connect(即：如同调用上面的connect()方法，
            bufOutPut = new BufferedOutputStream(httpConn.getOutputStream());
            httpConn.connect();
            byte[] bdat = requestParamsJson.getBytes("UTF-8");// 解决中文乱码问题
            bufOutPut.write(bdat, 0, bdat.length);
            bufOutPut.flush();

            // 根据ResponseCode判断连接是否成功
            int responseCode = httpConn.getResponseCode();
            if (responseCode != 200) {
                LOGGER.error(" Error===" + responseCode);
            } else {
                LOGGER.info("Post Success!");
            }
            // 定义BufferedReader输入流来读取URL的ResponseData
            bufferedReader = new BufferedReader(new InputStreamReader(httpConn.getInputStream()));
            String line;
            while ((line = bufferedReader.readLine()) != null) {
                System.out.println(line);
            }
        } catch (Exception e) {
            LOGGER.error("send post request error!" + e);
        } finally {
            httpConn.disconnect(); // 断开连接
            try {
                if (bufOutPut != null) {
                    bufOutPut.close();
                }
                if (bufferedReader != null) {
                    bufferedReader.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
}