package com.whyc.util;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonSyntaxException;
import com.whyc.dto.Response;
import com.whyc.dto.Response4Http;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.*;
import java.lang.reflect.Type;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Map;

public class HttpUtil {

	/*
	 * 获取HttpServletRequest
	 */
	public static HttpServletRequest getRequest(){
		ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
		HttpServletRequest request = requestAttributes.getRequest();
		return request;
	}
	
	/*
	 * 获取HttpServletResponse
	 */
	public static HttpServletResponse getResponse(){
		ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
		HttpServletResponse response = requestAttributes.getResponse();
		return response;
	}
	
	/*
	 * 获取HttpSession
	 */
	public static HttpSession getSession(){
		return getRequest().getSession();
	} 
	
	/**
	 * 
	 * @return	返回application
	 */
	public static ServletContext getApplication(){
		return getSession().getServletContext();
	}

	/*
	 * 获取将对象转换成json格式
	 */
	public static String toJson(Object obj){
		Gson gson = new GsonBuilder().setDateFormat("yyyy-MM-dd HH:mm:ss").create();
		return gson.toJson(obj);
	}
	
	public static String chageDateToString(Date time,String type){
		String msg = "";
		SimpleDateFormat sdf = new SimpleDateFormat(type);
		msg = sdf.format(time);
		return msg;
	}

	
	/**
	 * 
	 * @param datetype	需要解析的日期的格式如："yyyy-MM-dd HH:mm:ss"
	 * @return	得到对应的gson对象
	 */
	public static Gson getGson(String datetype){
		return new  GsonBuilder().setDateFormat(datetype).create();
	}
	
	/**
	 * 获取默认的gson对象
	 * @return
	 */
	public static Gson getGson(){
		return new Gson();
	}
	
	
	public static <T> T getObject(String jsonstring,Type listtype){
		Gson gson=new Gson();
		T t=null;
		try {
			t=gson.fromJson(jsonstring, listtype);
		} catch (JsonSyntaxException e) {
			e.printStackTrace();
		}
		return t;
	}

	/**
	 * get方式的http请求
	 *
	 * @param httpUrl 请求地址
	 * @return 返回结果
	 */
	public static Response<String> doGet(String httpUrl, String queryParams) {
		HttpURLConnection connection = null;
		InputStream inputStream = null;
		BufferedReader bufferedReader = null;
		String result = null;// 返回结果字符串
		Response<String> response = new Response<>();
		try {
			// 创建远程url连接对象
			URL url = new URL(new StringBuffer(httpUrl).append("?").append(queryParams).toString());
			// 通过远程url连接对象打开一个连接，强转成httpURLConnection类
			connection = (HttpURLConnection) url.openConnection();
			// 设置连接方式：get
			connection.setRequestMethod("GET");
			// 设置连接主机服务器的超时时间：15000毫秒
			connection.setConnectTimeout(5000);
			// 设置读取远程返回的数据时间：60000毫秒
			connection.setReadTimeout(6000);
			// 发送请求
			connection.connect();
			// 通过connection连接，获取输入流
			if (connection.getResponseCode() == 200) {
				inputStream = connection.getInputStream();
				// 封装输入流，并指定字符集
				bufferedReader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
				// 存放数据
				StringBuilder sbf = new StringBuilder();
				String temp;
				while ((temp = bufferedReader.readLine()) != null) {
					sbf.append(temp);
					sbf.append(System.getProperty("line.separator"));
				}
				result = sbf.toString();
				response.set(1,result);
			}
		} catch (IOException e) {
			response.set(0);
			String message = e.getMessage();
			response.setData(message);
		} finally {
			// 关闭资源
			if (null != bufferedReader) {
				try {
					bufferedReader.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (null != inputStream) {
				try {
					inputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (connection != null) {
				connection.disconnect();// 关闭远程连接
			}
		}
		return response;
	}

	public static Response<String> doPost(String httpUrl, String requestBody) {
		HttpURLConnection connection = null;
		InputStream inputStream = null;
		OutputStream outputStream =null;
		BufferedReader bufferedReader = null;
		String result = null;// 返回结果字符串
		Response<String> response = new Response<>();
		try {
			// 创建远程url连接对象
			URL url = new URL(new StringBuffer(httpUrl).toString());
			// 通过远程url连接对象打开一个连接，强转成httpURLConnection类
			connection = (HttpURLConnection) url.openConnection();
			// 设置连接方式：post
			connection.setRequestMethod("POST");
			// 设置连接主机服务器的超时时间：15000毫秒
			connection.setConnectTimeout(5000);
			// 设置读取远程返回的数据时间：60000毫秒
			connection.setReadTimeout(6000);

			//请求体
			connection.setDoOutput(true);
			outputStream = connection.getOutputStream();
			OutputStreamWriter osw = new OutputStreamWriter(outputStream,"UTF-8");

			osw.write(requestBody);
			osw.flush();
			// 发送请求
			connection.connect();
			// 通过connection连接，获取输入流
			if (connection.getResponseCode() == 200) {
				inputStream = connection.getInputStream();
				// 封装输入流，并指定字符集
				bufferedReader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
				// 存放数据
				StringBuilder sbf = new StringBuilder();
				String temp;
				while ((temp = bufferedReader.readLine()) != null) {
					sbf.append(temp);
					sbf.append(System.getProperty("line.separator"));
				}
				result = sbf.toString();
				response.set(1);
				response.setData(result);
			}
		} catch (IOException e) {
			String message = e.getMessage();
			response.set(0);
			response.setData(message);
		} finally {
			// 关闭资源
			if (null != bufferedReader) {
				try {
					bufferedReader.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (null != inputStream) {
				try {
					inputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (connection != null) {
				connection.disconnect();// 关闭远程连接
			}
			if (null != outputStream) {
				try {
					outputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
		return response;
	}

	/**
	 * 将map型转为请求参数型
	 *
	 * @param data
	 * @return
	 */
	public static String urlEncode(Map<String, ?> data) {
		StringBuilder sb = new StringBuilder();
		for (Map.Entry<String, ?> i : data.entrySet()) {
			try {
				sb.append(i.getKey()).append("=").append(URLEncoder.encode(i.getValue() + "", "UTF-8")).append("&");
			} catch (UnsupportedEncodingException e) {
				e.printStackTrace();
			}
		}
		String result = sb.toString();
		result = result.substring(0, result.lastIndexOf("&"));
		return result;
	}

	/**
	 * 执行GET请求,传入Map参数和Url,获取响应
	 */
	public static Response4Http doGet(String httpUrl, Map<String, ?> params) {
		Response4Http responseResult = new Response4Http<>();

		String queryParams = urlEncode(params);
		Response response = HttpUtil.doGet(httpUrl, queryParams);
		Integer httpResponseCode = response.getCode();
		String responseJson = (String) response.getData();
		if(httpResponseCode == 1) { //请求成功
			Response4Http responseHttp = HttpUtil.getGson().fromJson(responseJson, Response4Http.class);
			if(responseHttp.getCode() == 0 ) { //接口返回状态码为成功
				//返回信息有 data属性
				if(responseHttp.getData()!=null) {
					return responseResult.setII(1,true,responseHttp.getData(),null);
				}
				//返回信息有 status属性
				else if(responseHttp.getStatus() !=null){
					return responseResult.setStatus(1,true,responseHttp.getStatus());
				}
				//返回信息有 result属性
				else if(responseHttp.getResult() !=null){
					responseResult.setResult(responseHttp.getResult());
					return responseResult.set(1,true);
				}
				else{
					return responseResult.set(1,true,"请求成功且返回数据正常,无数据信息");
				}
			}else{ //接口返回状态码为失败
				// 返回信息有 msg属性
				return responseResult.set(1,false,responseHttp.getMsg());
			}
		}else{ //请求失败
			return responseResult.set(0,response.getData(),response.getMsg());
		}

	}
}