package org.gcube.accounting.insert.storage.utils;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.List;

import org.gcube.common.authorization.library.provider.SecurityTokenProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.gson.Gson;

/**
 * Retrieves the list user form the base url of the social-networking service in
 * the scope provided
 * 
 * @author Alessandro Pieve at ISTI-CNR (alessandro.pieve@isti.cnr.it)
 */
public class DiscoveryListUser {

	private static Logger log = LoggerFactory.getLogger(DiscoveryListUser.class);

	private List<String> listUser = null;

	public DiscoveryListUser(String context, String urlService) {

		try {
			String token = SecurityTokenProvider.instance.get();
			DiscoveryServiceListUser discoveryList = new DiscoveryServiceListUser(context);
			if (urlService == null) {
				urlService = discoveryList.getBasePath() + "=" + token;
			}
			log.debug("service DiscoveryServiceListUser:" + urlService);
			log.debug("scope:{} ,tokend:{}", context, token);
			String data = getJSON(urlService);
			log.debug("data read:{}", data);
			ListUser msg = new Gson().fromJson(data, ListUser.class);
			// TODO for debug limit a list user:
			listUser = msg.getResult();
		} catch (Exception ex) {
			log.error("DiscoveryListUserException:{}", ex);
			throw ex;
		}
	}

	public List<String> getListUser() {
		return listUser;
	}

	public String getJSON(String url) {
		HttpURLConnection c = null;
		try {
			URL u = new URL(url);
			c = (HttpURLConnection) u.openConnection();
			c.setRequestMethod("GET");
			c.setRequestProperty("Content-length", "0");
			HttpURLConnection.setFollowRedirects(true);
			c.setUseCaches(false);
			c.setAllowUserInteraction(false);
			c.connect();
			int status = c.getResponseCode();
			log.debug("status:{}", status);
			switch (status) {
			case 200:
			case 201:
				BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
				StringBuilder sb = new StringBuilder();
				String line;
				while ((line = br.readLine()) != null) {
					sb.append(line + "\n");
				}
				br.close();
				return sb.toString();
			}

		} catch (MalformedURLException ex) {
			log.error("MalformedURLException:{}", ex);

		} catch (IOException ex) {
			log.error("IOException:{}", ex);
		} finally {
			if (c != null) {
				try {
					c.disconnect();
				} catch (Exception ex) {
					log.error("Exception:{}", ex);
				}
			}
		}
		return null;
	}
}