package com.basic.easemob;

import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.apache.log4j.Logger;
import org.json.JSONObject;

/**
 * 环信IM配置
 * 
 * @company 北京贝思科技术有限公司
 * @author liuyajun, 8384503@qq.com
 * @date 2016年1月26日
 * @time 上午9:57:10
 */
public class IMConfig {
	private static Logger log = Logger.getLogger(IMConfig.class);
	
	public static String ENCODING = "UTF-8";
	
	public static String API_HTTP_SCHEMA = "https";

	public static String API_SERVER_HOST = "";

	public static String APPKEY = "";
	
	public static String APP_URL_ROOT = "";
	
	public static String APP_CLIENT_ID = "";
	
	public static String APP_CLIENT_SECRET = "";

	static {
		try {
			Properties p = new Properties();
			
			InputStream inputStream = IMConfig.class.getResourceAsStream(
					"config.properties");

			p.load(inputStream);

			API_SERVER_HOST = p.getProperty("API_SERVER_HOST");
			APPKEY = p.getProperty("APPKEY");
			APP_CLIENT_ID = p.getProperty("APP_CLIENT_ID");
			APP_CLIENT_SECRET = p.getProperty("APP_CLIENT_SECRET");

			APP_URL_ROOT = APPKEY.replace("#", "/");
			
		} catch (Throwable e1) {
			e1.printStackTrace();
		}
	}
	
	/**
	 * 前缀已经包含本公司的本app
	 * @param path 需以/开头
	 * @return
	 * @throws MalformedURLException
	 */
	public static URL getURL(String path) {
		URL url;
		try {
			url = new URL(IMConfig.API_HTTP_SCHEMA, IMConfig.API_SERVER_HOST, 
					"/" + APP_URL_ROOT + path);
		} catch (MalformedURLException e) {
			throw new RuntimeException(e);
		}

		return url;
	}

	/**
	 * Check illegal String
	 * 
	 * @param regex
	 * @param str
	 * @return
	 */
	public static boolean match(String regex, String str) {
		Pattern pattern = Pattern.compile(regex);
		Matcher matcher = pattern.matcher(str);

		return matcher.lookingAt();
	}

	private static String tokenAcessToken = null;
	private static Long tokenExpiredAt = null;

	/**
	 * 获取token
	 * @return
	 */
	public static String getToken(){
		//如果当前没有，如已超时
		if (null == tokenAcessToken || tokenAcessToken.trim().length()==0
				|| System.currentTimeMillis() > tokenExpiredAt) {
			
			HttpClient client = HttpUtil.getClient(true);
			
			try {
				URL tokenUrl = getURL("/token");
				
				JSONObject data = new JSONObject();
				data.put("grant_type", "client_credentials");
				data.put("client_id", APP_CLIENT_ID);
				data.put("client_secret", APP_CLIENT_SECRET);
				
				List<NameValuePair> headers = new ArrayList<NameValuePair>();
				headers.add(new BasicNameValuePair("Content-Type", "application/json"));

				HttpPost httpPost = new HttpPost();
				httpPost.setURI(tokenUrl.toURI());

                for (NameValuePair nameValuePair : headers) {
                    httpPost.addHeader(nameValuePair.getName(), nameValuePair.getValue());
                }
				httpPost.setEntity(new StringEntity(data.toString(), ENCODING));

				HttpResponse tokenResponse = client.execute(httpPost);
				HttpEntity entity = tokenResponse.getEntity();

				String results = EntityUtils.toString(entity, ENCODING);

				log.info("获取token: " + results);

				tokenAcessToken = "";
				if (tokenResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
					JSONObject json = new JSONObject(results);
					tokenAcessToken = json.getString("access_token");
					tokenExpiredAt = System.currentTimeMillis() + 
							json.getInt("expires_in") * 1000;
				}
				
			} catch (Throwable e) {
				throw new RuntimeException(e);
			}finally{
				
			}
		}

		return tokenAcessToken;
	}
}