Update invitation on accept/decline

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

@@ -3941,7 +3941,8 @@ public class MessageHelper {
                                     // https://developer.android.com/guide/topics/providers/calendar-provider#delete-event
                                     Uri deleteUri = ContentUris.withAppendedId(CalendarContract.Events.CONTENT_URI, eventId);
                                     int rows = resolver.delete(deleteUri, null, null);
-                                    EntityLog.log(context, EntityLog.Type.General, message, "Deleted event id=" + eventId + " rows=" + rows);
+                                    EntityLog.log(context, EntityLog.Type.General, message,
+                                            "Deleted event id=" + eventId + " rows=" + rows);
                                 }
                             }
 
@@ -3993,7 +3994,6 @@ public class MessageHelper {
                                     if (!TextUtils.isEmpty(location))
                                         values.put(CalendarContract.Events.EVENT_LOCATION, location);
                                     values.put(CalendarContract.Events.STATUS, CalendarContract.Events.STATUS_TENTATIVE);
-                                    values.put(CalendarContract.Events.AVAILABILITY, CalendarContract.Events.AVAILABILITY_TENTATIVE);
 
                                     Uri uri = resolver.insert(CalendarContract.Events.CONTENT_URI, values);
                                     long eventId = Long.parseLong(uri.getLastPathSegment());

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

@@ -19,21 +19,28 @@ package eu.faircode.email;
     Copyright 2018-2022 by Marcel Bokhorst (M66B)
 */
 
+import android.Manifest;
 import android.app.AlarmManager;
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.content.BroadcastReceiver;
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.ContentValues;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.SharedPreferences;
+import android.database.Cursor;
 import android.net.ConnectivityManager;
 import android.net.Network;
 import android.net.NetworkCapabilities;
 import android.net.NetworkRequest;
+import android.net.Uri;
 import android.os.PowerManager;
 import android.os.SystemClock;
+import android.provider.CalendarContract;
 import android.text.TextUtils;
 
 import androidx.annotation.NonNull;
@@ -68,6 +75,14 @@ import javax.mail.Session;
 import javax.mail.internet.InternetAddress;
 import javax.mail.internet.MimeMessage;
 
+import biweekly.Biweekly;
+import biweekly.ICalendar;
+import biweekly.component.VEvent;
+import biweekly.parameter.ParticipationStatus;
+import biweekly.property.Attendee;
+import biweekly.property.Method;
+import biweekly.property.Uid;
+
 public class ServiceSend extends ServiceBase implements SharedPreferences.OnSharedPreferenceChangeListener {
     private TupleUnsent lastUnsent = null;
     private Network lastActive = null;
@@ -850,18 +865,82 @@ public class ServiceSend extends ServiceBase implements SharedPreferences.OnShar
 
                 // Message could have been deleted
                 EntityMessage orphan = db.message().getMessage(sid);
-                if (orphan != null)
+                if (orphan != null) {
                     EntityOperation.queue(this, orphan, EntityOperation.EXISTS);
+                }
 
                 db.setTransactionSuccessful();
             } finally {
                 db.endTransaction();
             }
+
+            checkICalendar(sid);
         }
 
         ServiceSynchronize.eval(this, "sent");
     }
 
+    private void checkICalendar(long sid) {
+        boolean permission = Helper.hasPermission(this, Manifest.permission.WRITE_CALENDAR);
+        if (!permission)
+            return;
+
+        DB db = DB.getInstance(this);
+        List<EntityAttachment> attachments = db.attachment().getAttachments(sid);
+        if (attachments == null || attachments.size() == 0)
+            return;
+
+        for (EntityAttachment attachment : attachments)
+            if ("text/calendar".equals(attachment.type))
+                try {
+                    File ics = attachment.getFile(this);
+                    ICalendar icalendar = Biweekly.parse(ics).first();
+
+                    Method method = icalendar.getMethod();
+                    if (method == null || !method.isReply())
+                        return;
+
+                    VEvent event = icalendar.getEvents().get(0);
+                    Uid uid = event.getUid();
+                    List<Attendee> attendees = event.getAttendees();
+                    if (uid == null || attendees == null || attendees.size() == 0)
+                        return;
+
+                    ParticipationStatus status = attendees.get(0).getParticipationStatus();
+                    if (!ParticipationStatus.ACCEPTED.equals(status) &&
+                            !ParticipationStatus.DECLINED.equals(status))
+                        return;
+
+                    ContentResolver resolver = getContentResolver();
+                    try (Cursor cursor = resolver.query(CalendarContract.Events.CONTENT_URI,
+                            new String[]{CalendarContract.Events._ID},
+                            CalendarContract.Events.UID_2445 + " = ? ",
+                            new String[]{uid.getValue()},
+                            null)) {
+                        while (cursor.moveToNext()) {
+                            long eventId = cursor.getLong(0);
+
+                            // https://developer.android.com/guide/topics/providers/calendar-provider#modify-calendar
+                            Uri updateUri = ContentUris.withAppendedId(CalendarContract.Events.CONTENT_URI, eventId);
+                            ContentValues values = new ContentValues();
+                            if (ParticipationStatus.ACCEPTED.equals(status))
+                                values.put(CalendarContract.Events.STATUS, CalendarContract.Events.STATUS_CONFIRMED);
+                            else
+                                values.put(CalendarContract.Events.STATUS, CalendarContract.Events.STATUS_CANCELED);
+                            int rows = resolver.update(updateUri, values, null, null);
+
+                            EntityMessage message = db.message().getMessage(sid);
+                            EntityLog.log(this, EntityLog.Type.General, message,
+                                    "Updated event id=" + eventId + " rows=" + rows);
+                        }
+                    }
+
+                    break;
+                } catch (Throwable ex) {
+                    Log.e(ex);
+                }
+    }
+
     static void boot(final Context context) {
         executor.submit(new Runnable() {
             @Override