org.physical_web.physicalweb.UrlDeviceDiscoveryService.java Source code

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Here is the source code for org.physical_web.physicalweb.UrlDeviceDiscoveryService.java

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/*
 * Copyright 2014 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.physical_web.physicalweb;

import org.physical_web.collection.PhysicalWebCollection;
import org.physical_web.collection.PhysicalWebCollectionException;
import org.physical_web.collection.PwPair;
import org.physical_web.collection.PwsResult;
import org.physical_web.collection.PwsResultCallback;
import org.physical_web.collection.PwsResultIconCallback;
import org.physical_web.collection.UrlDevice;

import android.app.Notification;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.graphics.Color;
import android.os.Binder;
import android.os.Build;
import android.os.Handler;
import android.os.IBinder;
import android.preference.PreferenceManager;
import android.support.v4.app.NotificationCompat;
import android.support.v4.app.NotificationManagerCompat;
import android.view.View;
import android.widget.RemoteViews;

import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.List;
import java.util.concurrent.TimeUnit;

/**
 * This is a service that scans for nearby Physical Web Objects.
 * It is created by MainActivity.
 * It finds nearby ble beacons,
 * and stores a count of them.
 * It also listens for screen on/off events
 * and start/stops the scanning accordingly.
 * It also silently issues a notification
 * informing the user of nearby beacons.
 * As beacons are found and lost,
 * the notification is updated to reflect
 * the current number of nearby beacons.
 */

public class UrlDeviceDiscoveryService extends Service implements UrlDeviceDiscoverer.UrlDeviceDiscoveryCallback {

    private static final String TAG = UrlDeviceDiscoveryService.class.getSimpleName();
    private static final String NOTIFICATION_GROUP_KEY = "URI_BEACON_NOTIFICATIONS";
    private static final String PREFS_VERSION_KEY = "prefs_version";
    private static final String SCAN_START_TIME_KEY = "scan_start_time";
    private static final String PW_COLLECTION_KEY = "pw_collection";
    private static final int PREFS_VERSION = 2;
    private static final int NEAREST_BEACON_NOTIFICATION_ID = 23;
    private static final int SECOND_NEAREST_BEACON_NOTIFICATION_ID = 24;
    private static final int SUMMARY_NOTIFICATION_ID = 25;
    private static final int NON_LOLLIPOP_NOTIFICATION_TITLE_COLOR = Color.parseColor("#ffffff");
    private static final int NON_LOLLIPOP_NOTIFICATION_URL_COLOR = Color.parseColor("#999999");
    private static final int NON_LOLLIPOP_NOTIFICATION_SNIPPET_COLOR = Color.parseColor("#999999");
    private static final int NOTIFICATION_VISIBILITY = NotificationCompat.VISIBILITY_PUBLIC;
    private static final long FIRST_SCAN_TIME_MILLIS = TimeUnit.SECONDS.toMillis(2);
    private static final long SECOND_SCAN_TIME_MILLIS = TimeUnit.SECONDS.toMillis(10);
    private static final long SCAN_STALE_TIME_MILLIS = TimeUnit.MINUTES.toMillis(2);
    private static final long LOCAL_SCAN_STALE_TIME_MILLIS = TimeUnit.SECONDS.toMillis(30);
    private boolean mCanUpdateNotifications = false;
    private boolean mSecondScanComplete = false;
    private boolean mIsBound = false;
    private long mScanStartTime;
    private Handler mHandler;
    private NotificationManagerCompat mNotificationManager;
    private List<UrlDeviceDiscoverer> mUrlDeviceDiscoverers;
    private List<UrlDeviceDiscoveryListener> mUrlDeviceDiscoveryListeners;
    private PhysicalWebCollection mPwCollection;

    // Notification of urls happens as follows:
    // 0. Begin scan
    // 1. Delete notification, show top two urls (mFirstScanTimeout)
    // 2. Show each new url as it comes in, if it's in the top two
    // 3. Stop scanning if no clients are subscribed (mSecondScanTimeout)

    private Runnable mFirstScanTimeout = new Runnable() {
        @Override
        public void run() {
            mCanUpdateNotifications = true;
            updateNotifications();
        }
    };

    private Runnable mSecondScanTimeout = new Runnable() {
        @Override
        public void run() {
            mSecondScanComplete = true;
            if (!mIsBound) {
                stopSelf();
            }
        }
    };

    /**
     * Binder class for getting connections to the service.
     */
    public class LocalBinder extends Binder {
        public UrlDeviceDiscoveryService getServiceInstance() {
            return UrlDeviceDiscoveryService.this;
        }
    }

    private IBinder mBinder = new LocalBinder();

    /**
     * Callback for subscribers to this service.
     */
    public interface UrlDeviceDiscoveryListener {
        public void onUrlDeviceDiscoveryUpdate();
    }

    public UrlDeviceDiscoveryService() {
    }

    private void initialize() {
        mNotificationManager = NotificationManagerCompat.from(this);
        mUrlDeviceDiscoverers = new ArrayList<>();

        if (Utils.isMdnsEnabled(this)) {
            Log.d(TAG, "mdns started");
            mUrlDeviceDiscoverers.add(new MdnsUrlDeviceDiscoverer(this));
        }
        if (Utils.isWifiDirectEnabled(this)) {
            Log.d(TAG, "wifi direct started");
            mUrlDeviceDiscoverers.add(new WifiUrlDeviceDiscoverer(this));
        }
        mUrlDeviceDiscoverers.add(new SsdpUrlDeviceDiscoverer(this));
        mUrlDeviceDiscoverers.add(new BleUrlDeviceDiscoverer(this));
        for (UrlDeviceDiscoverer urlDeviceDiscoverer : mUrlDeviceDiscoverers) {
            urlDeviceDiscoverer.setCallback(this);
        }
        mUrlDeviceDiscoveryListeners = new ArrayList<>();
        mHandler = new Handler();
        mPwCollection = new PhysicalWebCollection();
        if (!Utils.setPwsEndpoint(this, mPwCollection)) {
            Utils.warnUserOnMissingApiKey(this);
        }
        mCanUpdateNotifications = false;
    }

    private void restoreCache() {
        // Make sure we are trying to load the right version of the cache
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
        int prefsVersion = prefs.getInt(PREFS_VERSION_KEY, 0);
        long now = new Date().getTime();
        if (prefsVersion != PREFS_VERSION) {
            mScanStartTime = now;
            return;
        }

        // Don't load the cache if it's stale
        mScanStartTime = prefs.getLong(SCAN_START_TIME_KEY, 0);
        long scanDelta = now - mScanStartTime;
        if (scanDelta >= SCAN_STALE_TIME_MILLIS) {
            mScanStartTime = now;
            return;
        }

        // Restore the cached metadata
        try {
            JSONObject serializedCollection = new JSONObject(prefs.getString(PW_COLLECTION_KEY, null));
            mPwCollection = PhysicalWebCollection.jsonDeserialize(serializedCollection);
            Utils.setPwsEndpoint(this, mPwCollection);
        } catch (JSONException e) {
            Log.e(TAG, "Could not restore Physical Web collection cache", e);
        } catch (PhysicalWebCollectionException e) {
            Log.e(TAG, "Could not restore Physical Web collection cache", e);
        }
        // replace TxPower and RSSI data after restoring cache
        for (UrlDevice urlDevice : mPwCollection.getUrlDevices()) {
            if (Utils.isBleUrlDevice(urlDevice)) {
                Utils.updateRegion(urlDevice);
            }
        }
        // Unresolvable devices are typically not
        // relevant outside of scan range. Hence,
        // we specially clean them from the cache.
        if (scanDelta >= LOCAL_SCAN_STALE_TIME_MILLIS) {
            for (UrlDevice urlDevice : mPwCollection.getUrlDevices()) {
                if (!Utils.isResolvableDevice(urlDevice)) {
                    mPwCollection.removeUrlDevice(urlDevice);
                }
            }
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        initialize();
        restoreCache();
        cancelNotifications();
        mHandler.postDelayed(mFirstScanTimeout, FIRST_SCAN_TIME_MILLIS);
        mHandler.postDelayed(mSecondScanTimeout, SECOND_SCAN_TIME_MILLIS);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        startScan();
        return START_STICKY;
    }

    @Override
    public IBinder onBind(Intent intent) {
        mIsBound = true;
        return mBinder;
    }

    @Override
    public boolean onUnbind(Intent intent) {
        mIsBound = false;
        if (mSecondScanComplete) {
            stopSelf();
        }
        // true ensures onRebind is called on succcessive binds
        return true;
    }

    @Override
    public void onRebind(Intent intent) {
        mIsBound = true;
    }

    private void cancelNotifications() {
        mNotificationManager.cancel(NEAREST_BEACON_NOTIFICATION_ID);
        mNotificationManager.cancel(SECOND_NEAREST_BEACON_NOTIFICATION_ID);
        mNotificationManager.cancel(SUMMARY_NOTIFICATION_ID);
    }

    private void saveCache() {
        // Write the PW Collection
        PreferenceManager.getDefaultSharedPreferences(this).edit().putInt(PREFS_VERSION_KEY, PREFS_VERSION)
                .putLong(SCAN_START_TIME_KEY, mScanStartTime)
                .putString(PW_COLLECTION_KEY, mPwCollection.jsonSerialize().toString()).apply();
    }

    @Override
    public void onDestroy() {
        Log.d(TAG, "onDestroy:  service exiting");

        // Stop the scanners
        mHandler.removeCallbacks(mFirstScanTimeout);
        mHandler.removeCallbacks(mSecondScanTimeout);
        stopScan();
        saveCache();
        super.onDestroy();
    }

    @Override
    public void onUrlDeviceDiscovered(UrlDevice urlDevice) {
        // Add Device and fetch results
        // Don't short circuit because icons
        // and metadata may not be fetched
        mPwCollection.addUrlDevice(urlDevice);
        Log.d(TAG, urlDevice.getUrl());
        if (!Utils.isResolvableDevice(urlDevice)) {
            mPwCollection.addMetadata(new PwsResult.Builder(urlDevice.getUrl(), urlDevice.getUrl())
                    .setTitle(Utils.getTitle(urlDevice)).setDescription(Utils.getDescription(urlDevice)).build());
        }
        mPwCollection.fetchPwsResults(new PwsResultCallback() {
            long mPwsTripTimeMillis = 0;

            @Override
            public void onPwsResult(PwsResult pwsResult) {
                PwsResult replacement = new Utils.PwsResultBuilder(pwsResult)
                        .setPwsTripTimeMillis(pwsResult, mPwsTripTimeMillis).build();
                mPwCollection.addMetadata(replacement);
                triggerCallback();
                updateNotifications();
            }

            @Override
            public void onPwsResultAbsent(String url) {
                triggerCallback();
            }

            @Override
            public void onPwsResultError(Collection<String> urls, int httpResponseCode, Exception e) {
                Log.d(TAG, "PwsResultError: " + httpResponseCode + " ", e);
                triggerCallback();
            }

            @Override
            public void onResponseReceived(long durationMillis) {
                mPwsTripTimeMillis = durationMillis;
            }
        }, new PwsResultIconCallback() {
            @Override
            public void onIcon(byte[] icon) {
                triggerCallback();
            }

            @Override
            public void onError(int httpResponseCode, Exception e) {
                Log.d(TAG, "PwsResultError: " + httpResponseCode + " ", e);
                triggerCallback();
            }
        });
        triggerCallback();
    }

    private void triggerCallback() {
        for (UrlDeviceDiscoveryListener urlDeviceDiscoveryListener : mUrlDeviceDiscoveryListeners) {
            urlDeviceDiscoveryListener.onUrlDeviceDiscoveryUpdate();
        }
    }

    /**
     * Create a new set of notifications or update those existing.
     */
    private void updateNotifications() {
        if (!mCanUpdateNotifications) {
            return;
        }

        List<PwPair> pwPairs = mPwCollection.getGroupedPwPairsSortedByRank(new Utils.PwPairRelevanceComparator());
        List<PwPair> notBlockedPwPairs = new ArrayList<>();
        for (PwPair i : pwPairs) {
            if (!Utils.isBlocked(i)) {
                notBlockedPwPairs.add(i);
            }
        }

        // If no beacons have been found
        if (notBlockedPwPairs.size() == 0) {
            // Remove all existing notifications
            cancelNotifications();
        } else if (notBlockedPwPairs.size() == 1) {
            updateNearbyBeaconNotification(true, notBlockedPwPairs.get(0), NEAREST_BEACON_NOTIFICATION_ID);
        } else {
            // Create a summary notification for both beacon notifications.
            // Do this first so that we don't first show the individual notifications
            updateSummaryNotification(notBlockedPwPairs);
            // Create or update a notification for second beacon
            updateNearbyBeaconNotification(false, notBlockedPwPairs.get(1), SECOND_NEAREST_BEACON_NOTIFICATION_ID);
            // Create or update a notification for first beacon. Needs to be added last to show up top
            updateNearbyBeaconNotification(false, notBlockedPwPairs.get(0), NEAREST_BEACON_NOTIFICATION_ID);

        }
    }

    /**
     * Create or update a notification with the given id for the beacon with the given address.
     */
    private void updateNearbyBeaconNotification(boolean single, PwPair pwPair, int notificationId) {
        PwsResult pwsResult = pwPair.getPwsResult();
        UrlDevice urlDevice = pwPair.getUrlDevice();
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
        builder.setSmallIcon(R.drawable.ic_notification).setLargeIcon(Utils.getBitmapIcon(mPwCollection, pwsResult))
                .setContentTitle(pwsResult.getTitle()).setContentText(pwsResult.getDescription()).setPriority(
                        (Utils.isFavorite(pwPair.getPwsResult().getSiteUrl())) ? NotificationCompat.PRIORITY_DEFAULT
                                : NotificationCompat.PRIORITY_MIN);
        if (Utils.isFatBeaconDevice(urlDevice)) {
            Intent intent = new Intent(this, OfflineTransportConnectionActivity.class);
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_CONNECTION_TYPE,
                    OfflineTransportConnectionActivity.EXTRA_FAT_BEACON_CONNECTION);
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_DEVICE_ADDRESS, pwsResult.getSiteUrl());
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_PAGE_TITLE, pwsResult.getTitle());
            int requestID = (int) System.currentTimeMillis();
            builder.setContentIntent(PendingIntent.getActivity(this, requestID, intent, 0));
        } else if (Utils.isWifiDirectDevice(urlDevice)) {
            Intent intent = new Intent(this, OfflineTransportConnectionActivity.class);
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_CONNECTION_TYPE,
                    OfflineTransportConnectionActivity.EXTRA_WIFI_DIRECT_CONNECTION);
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_DEVICE_ADDRESS,
                    Utils.getWifiAddress(urlDevice));
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_PAGE_TITLE, pwsResult.getTitle());
            intent.putExtra(OfflineTransportConnectionActivity.EXTRA_DEVICE_PORT, Utils.getWifiPort(urlDevice));
            int requestID = (int) System.currentTimeMillis();
            builder.setContentIntent(PendingIntent.getActivity(this, requestID, intent, 0));
        } else {
            builder.setContentIntent(Utils.createNavigateToUrlPendingIntent(pwsResult, this));
        }
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP
                && Utils.isPublic(pwPair.getUrlDevice())) {
            builder.setVisibility(NOTIFICATION_VISIBILITY);
        }
        // For some reason if there is only one notification and you call setGroup
        // the notification doesn't show up on the N7 running kit kat
        if (!single) {
            builder = builder.setGroup(NOTIFICATION_GROUP_KEY);
        }
        Notification notification = builder.build();

        mNotificationManager.notify(notificationId, notification);
    }

    /**
     * Create or update the a single notification that is a collapsed version
     * of the top two beacon notifications.
     */
    private void updateSummaryNotification(List<PwPair> pwPairs) {
        int numNearbyBeacons = pwPairs.size();
        String contentTitle = String.valueOf(numNearbyBeacons);
        Resources resources = getResources();
        contentTitle += " "
                + resources.getQuantityString(R.plurals.numFoundBeacons, numNearbyBeacons, numNearbyBeacons);
        String contentText = getString(R.string.summary_notification_pull_down);
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
        builder.setSmallIcon(R.drawable.ic_notification).setContentTitle(contentTitle).setContentText(contentText)
                .setSmallIcon(R.drawable.ic_notification).setGroup(NOTIFICATION_GROUP_KEY).setGroupSummary(true)
                .setPriority(Utils.containsFavorite(pwPairs) ? NotificationCompat.PRIORITY_DEFAULT
                        : NotificationCompat.PRIORITY_MIN)
                .setContentIntent(createReturnToAppPendingIntent());
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            builder.setVisibility(NOTIFICATION_VISIBILITY);
        }
        Notification notification = builder.build();

        // Create the big view for the notification (viewed by pulling down)
        RemoteViews remoteViews = updateSummaryNotificationRemoteViews(pwPairs);
        notification.bigContentView = remoteViews;

        mNotificationManager.notify(SUMMARY_NOTIFICATION_ID, notification);
    }

    /**
     * Create the big view for the summary notification.
     */
    private RemoteViews updateSummaryNotificationRemoteViews(List<PwPair> pwPairs) {
        RemoteViews remoteViews = new RemoteViews(getPackageName(), R.layout.notification_big_view);

        // Fill in the data for the top two beacon views
        updateSummaryNotificationRemoteViewsFirstBeacon(pwPairs.get(0), remoteViews);
        updateSummaryNotificationRemoteViewsSecondBeacon(pwPairs.get(1), remoteViews);

        // Create a pending intent that will open the physical web app
        // TODO(cco3): Use a clickListener on the VIEW MORE button to do this
        PendingIntent pendingIntent = createReturnToAppPendingIntent();
        remoteViews.setOnClickPendingIntent(R.id.otherBeaconsLayout, pendingIntent);

        return remoteViews;
    }

    private void updateSummaryNotificationRemoteViewsFirstBeacon(PwPair pwPair, RemoteViews remoteViews) {
        PwsResult pwsResult = pwPair.getPwsResult();
        remoteViews.setImageViewBitmap(R.id.icon_firstBeacon, Utils.getBitmapIcon(mPwCollection, pwsResult));
        remoteViews.setTextViewText(R.id.title_firstBeacon, pwsResult.getTitle());
        remoteViews.setTextViewText(R.id.url_firstBeacon, pwsResult.getSiteUrl());
        remoteViews.setTextViewText(R.id.description_firstBeacon, pwsResult.getDescription());
        // Recolor notifications to have light text for non-Lollipop devices
        if (!(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)) {
            remoteViews.setTextColor(R.id.title_firstBeacon, NON_LOLLIPOP_NOTIFICATION_TITLE_COLOR);
            remoteViews.setTextColor(R.id.url_firstBeacon, NON_LOLLIPOP_NOTIFICATION_URL_COLOR);
            remoteViews.setTextColor(R.id.description_firstBeacon, NON_LOLLIPOP_NOTIFICATION_SNIPPET_COLOR);
        }

        // Create an intent that will open the browser to the beacon's url
        // if the user taps the notification
        remoteViews.setOnClickPendingIntent(R.id.first_beacon_main_layout,
                Utils.createNavigateToUrlPendingIntent(pwsResult, this));
        remoteViews.setViewVisibility(R.id.firstBeaconLayout, View.VISIBLE);
    }

    private void updateSummaryNotificationRemoteViewsSecondBeacon(PwPair pwPair, RemoteViews remoteViews) {
        PwsResult pwsResult = pwPair.getPwsResult();
        remoteViews.setImageViewBitmap(R.id.icon_secondBeacon, Utils.getBitmapIcon(mPwCollection, pwsResult));
        remoteViews.setTextViewText(R.id.title_secondBeacon, pwsResult.getTitle());
        remoteViews.setTextViewText(R.id.url_secondBeacon, pwsResult.getSiteUrl());
        remoteViews.setTextViewText(R.id.description_secondBeacon, pwsResult.getDescription());
        // Recolor notifications to have light text for non-Lollipop devices
        if (!(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)) {
            remoteViews.setTextColor(R.id.title_secondBeacon, NON_LOLLIPOP_NOTIFICATION_TITLE_COLOR);
            remoteViews.setTextColor(R.id.url_secondBeacon, NON_LOLLIPOP_NOTIFICATION_URL_COLOR);
            remoteViews.setTextColor(R.id.description_secondBeacon, NON_LOLLIPOP_NOTIFICATION_SNIPPET_COLOR);
        }

        // Create an intent that will open the browser to the beacon's url
        // if the user taps the notification
        remoteViews.setOnClickPendingIntent(R.id.second_beacon_main_layout,
                Utils.createNavigateToUrlPendingIntent(pwsResult, this));
        remoteViews.setViewVisibility(R.id.secondBeaconLayout, View.VISIBLE);
    }

    private PendingIntent createReturnToAppPendingIntent() {
        Intent intent = new Intent(this, MainActivity.class);
        int requestID = (int) System.currentTimeMillis();
        PendingIntent pendingIntent = PendingIntent.getActivity(this, requestID, intent, 0);
        return pendingIntent;
    }

    public void addCallback(UrlDeviceDiscoveryListener urlDeviceDiscoveryListener) {
        mUrlDeviceDiscoveryListeners.add(urlDeviceDiscoveryListener);
    }

    public void removeCallback(UrlDeviceDiscoveryListener urlDeviceDiscoveryListener) {
        mUrlDeviceDiscoveryListeners.remove(urlDeviceDiscoveryListener);
    }

    public long getScanStartTime() {
        return mScanStartTime;
    }

    private void startScan() {
        for (UrlDeviceDiscoverer urlDeviceDiscoverer : mUrlDeviceDiscoverers) {
            urlDeviceDiscoverer.startScan();
        }
    }

    private void stopScan() {
        for (UrlDeviceDiscoverer urlDeviceDiscoverer : mUrlDeviceDiscoverers) {
            urlDeviceDiscoverer.stopScan();
        }
    }

    public void restartScan() {
        stopScan();
        mScanStartTime = new Date().getTime();
        startScan();
    }

    public boolean hasResults() {
        return !mPwCollection.getPwPairs().isEmpty();
    }

    public PhysicalWebCollection getPwCollection() {
        return mPwCollection;
    }

    public void clearCache() {
        stopScan();
        mScanStartTime = new Date().getTime();
        Utils.setPwsEndpoint(this, mPwCollection);
        mPwCollection.clear();
        saveCache();
    }

    public void newPwsStartScan() {
        Utils.setPwsEndpoint(this, mPwCollection);
        restartScan();
    }
}