/*
* $Id$
*/

package com.tokudu.demo;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.text.SimpleDateFormat;
import java.util.Date;

import android.os.Environment;

public class ConnectionLog
{
private String mPath;
private Writer mWriter;

private static final SimpleDateFormat TIMESTAMP_FMT =
new SimpleDateFormat("[HH:mm:ss] ");

public ConnectionLog()
throws IOException
{
File sdcard = Environment.getExternalStorageDirectory();
File logDir = new File(sdcard, "tokudu/log/");
if (!logDir.exists()) {
logDir.mkdirs();
// do not allow media scan
new File(logDir, ".nomedia").createNewFile();
}

open(logDir.getAbsolutePath() + "/push.log");
}

public ConnectionLog(String basePath)
throws IOException
{
open(basePath);
}

protected void open(String basePath)
throws IOException
{
File f = new File(basePath + "-" + getTodayString());
mPath = f.getAbsolutePath();
mWriter = new BufferedWriter(new FileWriter(mPath), 2048);

println("Opened log.");
}

private static String getTodayString()
{
SimpleDateFormat df = new SimpleDateFormat("yyyyMMdd-hhmmss");
return df.format(new Date());
}

public String getPath()
{
return mPath;
}

public void println(String message)
throws IOException
{
mWriter.write(TIMESTAMP_FMT.format(new Date()));
mWriter.write(message);
mWriter.write('\n');
mWriter.flush();
}

public void close()
throws IOException
{
mWriter.close();
}
}

package com.tokudu.demo;

import android.app.Activity;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.provider.Settings.Secure;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class PushActivity extends Activity {
private String mDeviceID;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

mDeviceID = Secure.getString(this.getContentResolver(), Secure.ANDROID_ID);
((TextView) findViewById(R.id.target_text)).setText(mDeviceID);

final Button startButton = ((Button) findViewById(R.id.start_button));
final Button stopButton = ((Button) findViewById(R.id.stop_button));
startButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Editor editor = getSharedPreferences(PushService.TAG, MODE_PRIVATE).edit();
editor.putString(PushService.PREF_DEVICE_ID, mDeviceID);
editor.commit();
PushService.actionStart(getApplicationContext());
startButton.setEnabled(false);
stopButton.setEnabled(true);
}
});
stopButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
PushService.actionStop(getApplicationContext());
startButton.setEnabled(true);
stopButton.setEnabled(false);
}
});
}

@Override
protected void onResume() {
super.onResume();

SharedPreferences p = getSharedPreferences(PushService.TAG, MODE_PRIVATE);
boolean started = p.getBoolean(PushService.PREF_STARTED, false);

((Button) findViewById(R.id.start_button)).setEnabled(!started);
((Button) findViewById(R.id.stop_button)).setEnabled(started);
}
}

package com.tokudu.demo;

import java.io.IOException;

import com.ibm.mqtt.IMqttClient;
import com.ibm.mqtt.MqttClient;
import com.ibm.mqtt.MqttException;
import com.ibm.mqtt.MqttPersistence;
import com.ibm.mqtt.MqttPersistenceException;
import com.ibm.mqtt.MqttSimpleCallback;

import android.app.AlarmManager;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.IBinder;
import android.util.Log;

/*
* PushService that does all of the work.
* Most of the logic is borrowed from KeepAliveService.
* http://code.google.com/p/android-random/source/browse/trunk/TestKeepAlive/src/org/devtcg/demo/keepalive/KeepAliveService.java?r=219
*/
public class PushService extends Service
{
// this is the log tag
public static final String TAG = "DemoPushService";

// the IP address, where your MQTT broker is running.
private static final String MQTT_HOST = "88.88.88.111";
// the port at which the broker is running.
private static int MQTT_BROKER_PORT_NUM = 1883;
// Let's not use the MQTT persistence.
private static MqttPersistence MQTT_PERSISTENCE = null;
// We don't need to remember any state between the connections, so we use a clean start.
private static boolean MQTT_CLEAN_START = true;
// Let's set the internal keep alive for MQTT to 15 mins. I haven't tested this value much. It could probably be increased.
private static short MQTT_KEEP_ALIVE = 60 * 15;
// Set quality of services to 0 (at most once delivery), since we don't want push notifications
// arrive more than once. However, this means that some messages might get lost (delivery is not guaranteed)
private static int[] MQTT_QUALITIES_OF_SERVICE = { 0 } ;
private static int MQTT_QUALITY_OF_SERVICE = 0;
// The broker should not retain any messages.
private static boolean MQTT_RETAINED_PUBLISH = false;

// MQTT client ID, which is given the broker. In this example, I also use this for the topic header.
// You can use this to run push notifications for multiple apps with one MQTT broker.
public static String MQTT_CLIENT_ID = "tokudu";

// These are the actions for the service (name are descriptive enough)
private static final String ACTION_START = MQTT_CLIENT_ID + ".START";
private static final String ACTION_STOP = MQTT_CLIENT_ID + ".STOP";
private static final String ACTION_KEEPALIVE = MQTT_CLIENT_ID + ".KEEP_ALIVE";
private static final String ACTION_RECONNECT = MQTT_CLIENT_ID + ".RECONNECT";

// Connection log for the push service. Good for debugging.
private ConnectionLog mLog;

// Connectivity manager to determining, when the phone loses connection
private ConnectivityManager mConnMan;
// Notification manager to displaying arrived push notifications
private NotificationManager mNotifMan;

// Whether or not the service has been started.
private boolean mStarted;

// This the application level keep-alive interval, that is used by the AlarmManager
// to keep the connection active, even when the device goes to sleep.
private static final long KEEP_ALIVE_INTERVAL = 1000 * 60 * 28;

// Retry intervals, when the connection is lost.
private static final long INITIAL_RETRY_INTERVAL = 1000 * 10;
private static final long MAXIMUM_RETRY_INTERVAL = 1000 * 60 * 30;

// Preferences instance
private SharedPreferences mPrefs;
// We store in the preferences, whether or not the service has been started
public static final String PREF_STARTED = "isStarted";
// We also store the deviceID (target)
public static final String PREF_DEVICE_ID = "deviceID";
// We store the last retry interval
public static final String PREF_RETRY = "retryInterval";

// Notification title
public static String NOTIF_TITLE = "Tokudu";
// Notification id
private static final int NOTIF_CONNECTED = 0;

// This is the instance of an MQTT connection.
private MQTTConnection mConnection;
private long mStartTime;

// Static method to start the service
public static void actionStart(Context ctx) {
Intent i = new Intent(ctx, PushService.class);
i.setAction(ACTION_START);
ctx.startService(i);
}

// Static method to stop the service
public static void actionStop(Context ctx) {
Intent i = new Intent(ctx, PushService.class);
i.setAction(ACTION_STOP);
ctx.startService(i);
}

// Static method to send a keep alive message
public static void actionPing(Context ctx) {
Intent i = new Intent(ctx, PushService.class);
i.setAction(ACTION_KEEPALIVE);
ctx.startService(i);
}

@Override
public void onCreate() {
super.onCreate();

log("Creating service");
mStartTime = System.currentTimeMillis();

try {
mLog = new ConnectionLog();
Log.i(TAG, "Opened log at " + mLog.getPath());
} catch (IOException e) {
Log.e(TAG, "Failed to open log", e);
}

// Get instances of preferences, connectivity manager and notification manager
mPrefs = getSharedPreferences(TAG, MODE_PRIVATE);
mConnMan = (ConnectivityManager)getSystemService(CONNECTIVITY_SERVICE);
mNotifMan = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);

/* If our process was reaped by the system for any reason we need
* to restore our state with merely a call to onCreate. We record
* the last "started" value and restore it here if necessary. */
handleCrashedService();
}

// This method does any necessary clean-up need in case the server has been destroyed by the system
// and then restarted
private void handleCrashedService() {
if (wasStarted() == true) {
log("Handling crashed service...");
// stop the keep alives
stopKeepAlives();

// Do a clean start
start();
}
}

@Override
public void onDestroy() {
log("Service destroyed (started=" + mStarted + ")");

// Stop the services, if it has been started
if (mStarted == true) {
stop();
}

try {
if (mLog != null)
mLog.close();
} catch (IOException e) {}
}

@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
log("Service started with intent=" + intent);

// Do an appropriate action based on the intent.
if (intent.getAction().equals(ACTION_STOP) == true) {
stop();
stopSelf();
} else if (intent.getAction().equals(ACTION_START) == true) {
start();
} else if (intent.getAction().equals(ACTION_KEEPALIVE) == true) {
keepAlive();
} else if (intent.getAction().equals(ACTION_RECONNECT) == true) {
if (isNetworkAvailable()) {
reconnectIfNecessary();
}
}
}

@Override
public IBinder onBind(Intent intent) {
return null;
}

// log helper function
private void log(String message) {
log(message, null);
}
private void log(String message, Throwable e) {
if (e != null) {
Log.e(TAG, message, e);

} else {
Log.i(TAG, message);
}

if (mLog != null)
{
try {
mLog.println(message);
} catch (IOException ex) {}
}
}

// Reads whether or not the service has been started from the preferences
private boolean wasStarted() {
return mPrefs.getBoolean(PREF_STARTED, false);
}

// Sets whether or not the services has been started in the preferences.
private void setStarted(boolean started) {
mPrefs.edit().putBoolean(PREF_STARTED, started).commit();
mStarted = started;
}

private synchronized void start() {
log("Starting service...");

// Do nothing, if the service is already running.
if (mStarted == true) {
Log.w(TAG, "Attempt to start connection that is already active");
return;
}

// Establish an MQTT connection
connect();

// Register a connectivity listener
registerReceiver(mConnectivityChanged, new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
}

private synchronized void stop() {
// Do nothing, if the service is not running.
if (mStarted == false) {
Log.w(TAG, "Attempt to stop connection not active.");
return;
}

// Save stopped state in the preferences
setStarted(false);

// Remove the connectivity receiver
unregisterReceiver(mConnectivityChanged);
// Any existing reconnect timers should be removed, since we explicitly stopping the service.
cancelReconnect();

// Destroy the MQTT connection if there is one
if (mConnection != null) {
mConnection.disconnect();
mConnection = null;
}
}

//
private synchronized void connect() {
log("Connecting...");
// fetch the device ID from the preferences.
String deviceID = mPrefs.getString(PREF_DEVICE_ID, null);
// Create a new connection only if the device id is not NULL
if (deviceID == null) {
log("Device ID not found.");
} else {
try {
mConnection = new MQTTConnection(MQTT_HOST, deviceID);
} catch (MqttException e) {
// Schedule a reconnect, if we failed to connect
log("MqttException: " + (e.getMessage() != null e.getMessage() : "NULL"));
if (isNetworkAvailable()) {
scheduleReconnect(mStartTime);
}
}
setStarted(true);
}
}

private synchronized void keepAlive() {
try {
// Send a keep alive, if there is a connection.
if (mStarted == true && mConnection != null) {
mConnection.sendKeepAlive();
}
} catch (MqttException e) {
log("MqttException: " + (e.getMessage() != null e.getMessage(): "NULL"), e);

mConnection.disconnect();
mConnection = null;
cancelReconnect();
}
}

// Schedule application level keep-alives using the AlarmManager
private void startKeepAlives() {
Intent i = new Intent();
i.setClass(this, PushService.class);
i.setAction(ACTION_KEEPALIVE);
PendingIntent pi = PendingIntent.getService(this, 0, i, 0);
AlarmManager alarmMgr = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP,
System.currentTimeMillis() + KEEP_ALIVE_INTERVAL,
KEEP_ALIVE_INTERVAL, pi);
}

// Remove all scheduled keep alives
private void stopKeepAlives() {
Intent i = new Intent();
i.setClass(this, PushService.class);
i.setAction(ACTION_KEEPALIVE);
PendingIntent pi = PendingIntent.getService(this, 0, i, 0);
AlarmManager alarmMgr = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmMgr.cancel(pi);
}

// We schedule a reconnect based on the starttime of the service
public void scheduleReconnect(long startTime) {
// the last keep-alive interval
long interval = mPrefs.getLong(PREF_RETRY, INITIAL_RETRY_INTERVAL);

// Calculate the elapsed time since the start
long now = System.currentTimeMillis();
long elapsed = now - startTime;

// Set an appropriate interval based on the elapsed time since start
if (elapsed < interval) {
interval = Math.min(interval * 4, MAXIMUM_RETRY_INTERVAL);
} else {
interval = INITIAL_RETRY_INTERVAL;
}

log("Rescheduling connection in " + interval + "ms.");

// Save the new internval
mPrefs.edit().putLong(PREF_RETRY, interval).commit();

// Schedule a reconnect using the alarm manager.
Intent i = new Intent();
i.setClass(this, PushService.class);
i.setAction(ACTION_RECONNECT);
PendingIntent pi = PendingIntent.getService(this, 0, i, 0);
AlarmManager alarmMgr = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmMgr.set(AlarmManager.RTC_WAKEUP, now + interval, pi);
}

// Remove the scheduled reconnect
public void cancelReconnect() {
Intent i = new Intent();
i.setClass(this, PushService.class);
i.setAction(ACTION_RECONNECT);
PendingIntent pi = PendingIntent.getService(this, 0, i, 0);
AlarmManager alarmMgr = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmMgr.cancel(pi);
}

private synchronized void reconnectIfNecessary() {
if (mStarted == true && mConnection == null) {
log("Reconnecting...");
connect();
}
}

// This receiver listeners for network changes and updates the MQTT connection
// accordingly
private BroadcastReceiver mConnectivityChanged = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
// Get network info
NetworkInfo info = (NetworkInfo)intent.getParcelableExtra (ConnectivityManager.EXTRA_NETWORK_INFO);

// Is there connectivity?
boolean hasConnectivity = (info != null && info.isConnected()) true : false;

log("Connectivity changed: connected=" + hasConnectivity);

if (hasConnectivity) {
reconnectIfNecessary();
} else if (mConnection != null) {
// if there no connectivity, make sure MQTT connection is destroyed
mConnection.disconnect();
cancelReconnect();
mConnection = null;
}
}
};

// Display the topbar notification
private void showNotification(String text) {
Notification n = new Notification();

n.flags |= Notification.FLAG_SHOW_LIGHTS;
n.flags |= Notification.FLAG_AUTO_CANCEL;

n.defaults = Notification.DEFAULT_ALL;

n.icon = com.tokudu.demo.R.drawable.icon;
n.when = System.currentTimeMillis();

// Simply open the parent activity
PendingIntent pi = PendingIntent.getActivity(this, 0,
new Intent(this, PushActivity.class), 0);

// Change the name of the notification here
n.setLatestEventInfo(this, NOTIF_TITLE, text, pi);

mNotifMan.notify(NOTIF_CONNECTED, n);
}

// Check if we are online
private boolean isNetworkAvailable() {
NetworkInfo info = mConnMan.getActiveNetworkInfo();
if (info == null) {
return false;
}
return info.isConnected();
}

// This inner class is a wrapper on top of MQTT client.
private class MQTTConnection implements MqttSimpleCallback {
IMqttClient mqttClient = null;

// Creates a new connection given the broker address and initial topic
public MQTTConnection(String brokerHostName, String initTopic) throws MqttException {
// Create connection spec
String mqttConnSpec = "tcp://" + brokerHostName + "@" + MQTT_BROKER_PORT_NUM;
// Create the client and connect
mqttClient = MqttClient.createMqttClient(mqttConnSpec, MQTT_PERSISTENCE);
String clientID = MQTT_CLIENT_ID + "/" + mPrefs.getString(PREF_DEVICE_ID, "");
mqttClient.connect(clientID, MQTT_CLEAN_START, MQTT_KEEP_ALIVE);

// register this client app has being able to receive messages
mqttClient.registerSimpleHandler(this);

// Subscribe to an initial topic, which is combination of client ID and device ID.
initTopic = MQTT_CLIENT_ID + "/" + initTopic;
subscribeToTopic(initTopic);

log("Connection established to " + brokerHostName + " on topic " + initTopic);

// Save start time
mStartTime = System.currentTimeMillis();
// Star the keep-alives
startKeepAlives();
}

// Disconnect
public void disconnect() {
try {
stopKeepAlives();
mqttClient.disconnect();
} catch (MqttPersistenceException e) {
log("MqttException" + (e.getMessage() != null e.getMessage():" NULL"), e);
}
}
/*
* Send a request to the message broker to be sent messages published with
* the specified topic name. Wildcards are allowed.
*/
private void subscribeToTopic(String topicName) throws MqttException {

if ((mqttClient == null) || (mqttClient.isConnected() == false)) {
// quick sanity check - don't try and subscribe if we don't have
// a connection
log("Connection error" + "No connection");
} else {
String[] topics = { topicName };
mqttClient.subscribe(topics, MQTT_QUALITIES_OF_SERVICE);
}
}
/*
* Sends a message to the message broker, requesting that it be published
* to the specified topic.
*/
private void publishToTopic(String topicName, String message) throws MqttException {
if ((mqttClient == null) || (mqttClient.isConnected() == false)) {
// quick sanity check - don't try and publish if we don't have
// a connection
log("No connection to public to");
} else {
mqttClient.publish(topicName,
message.getBytes(),
MQTT_QUALITY_OF_SERVICE,
MQTT_RETAINED_PUBLISH);
}
}

/*
* Called if the application loses it's connection to the message broker.
*/
public void connectionLost() throws Exception {
log("Loss of connection" + "connection downed");
stopKeepAlives();
// null itself
mConnection = null;
if (isNetworkAvailable() == true) {
reconnectIfNecessary();
}
}

/*
* Called when we receive a message from the message broker.
*/
public void publishArrived(String topicName, byte[] payload, int qos, boolean retained) {
// Show a notification
String s = new String(payload);
showNotification(s);
log("Got message: " + s);
}

public void sendKeepAlive() throws MqttException {
log("Sending keep alive");
// publish to a keep-alive topic
publishToTopic(MQTT_CLIENT_ID + "/keepalive", mPrefs.getString(PREF_DEVICE_ID, ""));
}
}
}