hostage/src/de/tudarmstadt/informatik/hostage/commons/HelperUtils.java

package de.tudarmstadt.informatik.hostage.commons;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.security.KeyStore;
import java.util.concurrent.ExecutionException;

import org.apache.http.HttpVersion;
import org.apache.http.client.HttpClient;
import org.apache.http.conn.ClientConnectionManager;
import org.apache.http.conn.scheme.PlainSocketFactory;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;
import de.tudarmstadt.informatik.hostage.net.MySSLSocketFactory;
import de.tudarmstadt.informatik.hostage.ui.MainActivity;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.os.Environment;
import android.text.TextUtils;

/**
 * Helper class with some static methods for general usage.
 * @author Lars Pandikow
 * @author Wulf Pfeiffer
 *
 */
public final class HelperUtils {

	/**
	 * Gets SSID of the wireless network.
	 * @param context Needs a context to get system recourses
	 * @return SSID of wireless network if connected, else null.
	 */
	public static String getSSID(Context context) {
		String ssid = null;
		ConnectivityManager connManager = (ConnectivityManager) context
				.getSystemService(Context.CONNECTIVITY_SERVICE);
		NetworkInfo networkInfo = connManager
				.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
		if (networkInfo != null && networkInfo.isConnected()) {
			final WifiManager wifiManager = (WifiManager) context
					.getSystemService(Context.WIFI_SERVICE);
			final WifiInfo connectionInfo = wifiManager.getConnectionInfo();
			if (connectionInfo != null
					&& !TextUtils.isEmpty(connectionInfo.getSSID())) {
				ssid = connectionInfo.getSSID();
			}
		}
		return ssid;
	}

	/**
	 * Gets BSSID of the wireless network.
	 * @param context Needs a context to get system recourses.
	 * @return BSSID of wireless network if connected, else null.
	 */
	public static String getBSSID(Context context) {
		String bssid = null;
		ConnectivityManager connManager = (ConnectivityManager) context
				.getSystemService(Context.CONNECTIVITY_SERVICE);
		NetworkInfo networkInfo = connManager
				.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
		if (networkInfo != null && networkInfo.isConnected()) {
			final WifiManager wifiManager = (WifiManager) context
					.getSystemService(Context.WIFI_SERVICE);
			final WifiInfo connectionInfo = wifiManager.getConnectionInfo();
			if (connectionInfo != null
					&& !TextUtils.isEmpty(connectionInfo.getSSID())) {
				bssid = connectionInfo.getBSSID();
			}
		}
		return bssid;
	}

	/**
	 * Gets internal IP address of the device in a wireless network.
	 * @param context Needs a context to get system recourses.
	 * @return internal IP of the device in a wireless network if connected, else null.
	 */
	public static String getInternalIP(Context context) {
		String ipAddress = null;
		ConnectivityManager connManager = (ConnectivityManager) context
				.getSystemService(Context.CONNECTIVITY_SERVICE);
		NetworkInfo networkInfo = connManager
				.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
		if (networkInfo != null && networkInfo.isConnected()) {
			final WifiManager wifiManager = (WifiManager) context
					.getSystemService(Context.WIFI_SERVICE);
			final WifiInfo connectionInfo = wifiManager.getConnectionInfo();
			if (connectionInfo != null) {
				try {
					ipAddress = InetAddress.getByAddress(
							unpackInetAddress(connectionInfo.getIpAddress()))
							.getHostAddress();
				} catch (UnknownHostException e) {
					e.printStackTrace();
				}
			}
		}
		return ipAddress;
	}

	private static byte[] unpackInetAddress(int bytes) {
		return new byte[] { (byte) ((bytes) & 0xff),
				(byte) ((bytes >>> 8) & 0xff), (byte) ((bytes >>> 16) & 0xff),
				(byte) ((bytes >>> 24) & 0xff) };
	}

	/**
	 * Determines and returns the external IP address of the device.
	 * @param context  Needs a context to get system recourses.
	 * @return A String representation of the external IP of the device.
	 * @see GetExternalIPTask
	 */
	public static String getExternalIP(Context context) {
		String ipAddress = null;
		GetExternalIPTask task = new GetExternalIPTask();
		task.execute(new String[]{"http://ip2country.sourceforge.net/ip2c.php?format=JSON"});
		try {
			ipAddress =  task.get();
		} catch (InterruptedException e) {
			e.printStackTrace();
		} catch (ExecutionException e) {
			e.printStackTrace();
		}
		return ipAddress;
	}
	 
	/**
	 * Updates the connextion info and saves them in the the SharedPreferences for session data.
	 * @param context Needs a context to get system recourses.
	 * @see MainActivity#SESSION_DATA
	 */
	public static void updateConnectionInfo(Context context) {	
		SharedPreferences pref = context.getSharedPreferences(MainActivity.SESSION_DATA, Context.MODE_PRIVATE);
		Editor editor = pref.edit();
		editor.putString(MainActivity.SSID, getSSID(context));
		editor.putString(MainActivity.BSSID, getBSSID(context));
		editor.putString(MainActivity.INTERNAL_IP, getInternalIP(context));
		editor.putString(MainActivity.EXTERNAL_IP, getExternalIP(context));
		editor.commit();
	}	

	/**
	 * Checks if external storage is available for read and write.
	 * @return True if external storage is available for read and write, else false.
	 */
	public static boolean isExternalStorageWritable() {
		String state = Environment.getExternalStorageState();
		if (Environment.MEDIA_MOUNTED.equals(state)) {
			return true;
		}
		return false;
	}

	/**
	 * Creates a HttpClient with an own SSL Socket.
	 * @return HttpsClient who accepts accepts all certificates.
	 * @see MySSLSocketFactory
	 */
	public static HttpClient createHttpClient() {
		try {
			KeyStore trustStore = KeyStore.getInstance(KeyStore
					.getDefaultType());
			trustStore.load(null, null);

			SSLSocketFactory sf = new MySSLSocketFactory(trustStore);
			sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);

			HttpParams params = new BasicHttpParams();
			HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
			HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);

			SchemeRegistry registry = new SchemeRegistry();
			registry.register(new Scheme("http", PlainSocketFactory
					.getSocketFactory(), 80));
			registry.register(new Scheme("https", sf, 443));

			ClientConnectionManager ccm = new ThreadSafeClientConnManager(
					params, registry);

			return new DefaultHttpClient(ccm, params);
		} catch (Exception e) {
			e.printStackTrace();
			return new DefaultHttpClient();
		}
	}
	
	/**
	 * Concatenates several byte arrays.
	 * @param bytes The byte arrays.
	 * @return A single byte arrays containing all the bytes from the given arrays in the order they are given.
	 */
	public static byte[] concat(byte[]... bytes) {
		int newSize = 0;
		for (byte[] b : bytes)
			newSize += b.length;
		byte[] dst = new byte[newSize];

		int currentPos = 0;
		int newPos;
		for (byte[] b : bytes) {
			newPos = b.length;
			System.arraycopy(b, 0, dst, currentPos, newPos);
			currentPos += newPos;
		}
		return dst;
	}
}