Authorization.java

package se.chalmers.dat255.grupp12;

import com.google.gson.*;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.sql.SQLException;

/**
 * Date: 2013-10-01
 * Time: 12:57
 */
public class Authorization {

	private static final String AUTH_URL = "https://www.googleapis.com/oauth2/v1/userinfo?alt=json&access_token=";

	public static synchronized User authorize(String mail, String token) throws IOException, SQLException {
		JsonObject userInfo = getUserInfo(token);
		String name = userInfo.get("name").getAsString();
		String googleMail = userInfo.get("email").getAsString();
		System.out.println(googleMail + " == " + mail);

		if (googleMail.equals(mail)) {
			try {
				return Database.getInstance().getUser(mail);
			} catch (DataNotFoundException e) {
				return Database.getInstance().insertUser(new User(name, mail));
			}
		} else {
			return null;
		}
	}

	private static JsonObject getUserInfo(String token) throws IOException {
		URL url = new URL(AUTH_URL + token);
		HttpURLConnection con = (HttpURLConnection) url.openConnection();

		if (con.getResponseCode() != 200) {
			throw new RuntimeException("Google returns response code: " + con.getResponseCode());
		}
		InputStream in = new BufferedInputStream(con.getInputStream());
		java.util.Scanner s = new java.util.Scanner(in).useDelimiter("\\A");
		String result = s.hasNext() ? s.next() : "";
		return new JsonParser().parse(result).getAsJsonObject();
	}
}