Preview message text in notifications

FAQ.md

@@ -36,7 +36,6 @@ Anything on this list is in random order and *might* be added in the near future
 
 ## Frequently requested features
 
-* Previewing message text in notifications: this is not possible because the message text is initially not downloaded.
 * Swipe left/right to go to previous/next message: swiping also selects message text, so this would not work reliably.
 * Rich text editor: besides that very few people would use this on a small mobile device, Android doesn't support a rich text editor and most rich text editor open source projects are abandoned.
 * Widget to read e-mail: widgets can have limited user interaction only, so a widget to read e-mail would not be very useful.

README.md

@@ -37,9 +37,9 @@ See also [this FAQ](https://github.com/M66B/open-source-email/blob/master/FAQ.md
 * Dark/black theme
 * Account/identity colors
 * Notifications per account
+* Notifications with message preview
 * Reply templates
 * Search on server
-* Preview sender/subject/photo in new message notifications
 * Keyword management
 * Encryption/decryption ([OpenPGP](https://www.openpgp.org/))
 * Export settings

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -128,6 +128,7 @@ public class ServiceSynchronize extends LifecycleService {
     private final Object lock = new Object();
     private TupleAccountStats lastStats = null;
     private ServiceManager serviceManager = new ServiceManager();
+    private static ExecutorService executor = Executors.newSingleThreadExecutor(Helper.backgroundThreadFactory);
 
     private static final int NOTIFICATION_SYNCHRONIZE = 1;
 
@@ -178,7 +179,11 @@ public class ServiceSynchronize extends LifecycleService {
             private LongSparseArray<List<Integer>> notifying = new LongSparseArray<>();
 
             @Override
-            public void onChanged(List<TupleMessageEx> messages) {
+            public void onChanged(final List<TupleMessageEx> messages) {
+                executor.submit(new Runnable() {
+                    @Override
+                    public void run() {
+                        try {
                             NotificationManager nm = getSystemService(NotificationManager.class);
 
                             Widget.update(ServiceSynchronize.this, messages.size());
@@ -209,29 +214,36 @@ public class ServiceSynchronize extends LifecycleService {
                                 List<Integer> removed = notifying.get(account);
                                 for (Notification notification : notifications) {
                                     Integer id = (int) notification.extras.getLong("id", 0);
-                        if (id > 0) {
+                                    if (id != 0) {
                                         all.add(id);
                                         if (removed.contains(id))
                                             removed.remove(id);
-                            else
+                                        else {
+                                            removed.remove(Integer.valueOf(-id));
                                             added.add(id);
                                         }
                                     }
+                                }
 
                                 if (notifications.size() == 0)
                                     nm.cancel("unseen:" + account, 0);
 
                                 for (Integer id : removed)
-                        nm.cancel("unseen:" + account, id);
+                                    nm.cancel("unseen:" + account, Math.abs(id));
 
                                 for (Notification notification : notifications) {
                                     Integer id = (int) notification.extras.getLong("id", 0);
                                     if ((id == 0 && added.size() + removed.size() > 0) || added.contains(id))
-                            nm.notify("unseen:" + account, id, notification);
+                                        nm.notify("unseen:" + account, Math.abs(id), notification);
                                 }
 
                                 notifying.put(account, all);
                             }
+                        } catch (Throwable ex) {
+                            Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                        }
+                    }
+                });
             }
         });
     }
@@ -497,7 +509,7 @@ public class ServiceSynchronize extends LifecycleService {
 
         for (TupleMessageEx message : messages) {
             Bundle args = new Bundle();
-            args.putLong("id", message.id);
+            args.putLong("id", message.content ? message.id : -message.id);
 
             Intent thread = new Intent(this, ActivityView.class);
             thread.setAction("thread:" + message.thread);
@@ -554,6 +566,7 @@ public class ServiceSynchronize extends LifecycleService {
                     .setWhen(message.received)
                     .setDeleteIntent(piDelete)
                     .setPriority(Notification.PRIORITY_DEFAULT)
+                    .setOnlyAlertOnce(true)
                     .setCategory(Notification.CATEGORY_MESSAGE)
                     .setVisibility(Notification.VISIBILITY_PRIVATE)
                     .setGroup(group)
@@ -566,6 +579,16 @@ public class ServiceSynchronize extends LifecycleService {
                 if (!TextUtils.isEmpty(message.subject))
                     mbuilder.setContentText(message.subject);
 
+                if (message.content)
+                    try {
+                        String html = message.read(ServiceSynchronize.this);
+                        String text = (TextUtils.isEmpty(message.subject) ? "" : message.subject + ": ") + Jsoup.parse(html).text();
+                        mbuilder.setStyle(new Notification.BigTextStyle().bigText(text));
+                    } catch (IOException ex) {
+                        Log.e(Helper.TAG, ex + "/n" + Log.getStackTraceString(ex));
+                        mbuilder.setStyle(new Notification.BigTextStyle().bigText(ex.toString()));
+                    }
+
                 if (!TextUtils.isEmpty(message.avatar)) {
                     Cursor cursor = null;
                     try {