Execute operations for same priority ordered

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

@@ -179,7 +179,9 @@ public class Helper {
                 protected <T> RunnableFuture<T> newTaskFor(Runnable runnable, T value) {
                     RunnableFuture<T> task = super.newTaskFor(runnable, value);
                     if (runnable instanceof PriorityRunnable)
-                        return new PriorityFuture<T>(task, ((PriorityRunnable) runnable).getPriority());
+                        return new PriorityFuture<T>(task,
+                                ((PriorityRunnable) runnable).getPriority(),
+                                ((PriorityRunnable) runnable).getOrder());
                     else
                         return task;
                 }
@@ -221,17 +223,22 @@ public class Helper {
 
     private static class PriorityFuture<T> implements RunnableFuture<T> {
         private int priority;
+        private long order;
         private RunnableFuture<T> wrapped;
 
-        PriorityFuture(RunnableFuture<T> wrapped, int priority) {
-            this.priority = priority;
+        PriorityFuture(RunnableFuture<T> wrapped, int priority, long order) {
             this.wrapped = wrapped;
+            this.priority = priority;
+            this.order = order;
         }
 
         public int getPriority() {
-            return priority;
+            return this.priority;
         }
 
+        public long getOrder() {
+            return this.order;
+        }
 
         @Override
         public void run() {
@@ -270,8 +277,13 @@ public class Helper {
             if (r1 instanceof PriorityFuture<?> && r2 instanceof PriorityFuture<?>) {
                 Integer p1 = ((PriorityFuture<?>) r1).getPriority();
                 Integer p2 = ((PriorityFuture<?>) r2).getPriority();
-                Log.i("Priority " + p1 + "/" + p2 + "=" + p1.compareTo(p2));
-                return p1.compareTo(p2);
+                int p = p1.compareTo(p2);
+                if (p == 0) {
+                    Long o1 = ((PriorityFuture<?>) r1).getOrder();
+                    Long o2 = ((PriorityFuture<?>) r2).getOrder();
+                    return o1.compareTo(o2);
+                } else
+                    return p;
             } else
                 return 0;
         }
@@ -279,13 +291,19 @@ public class Helper {
 
     static class PriorityRunnable implements Runnable {
         private int priority;
+        private long order;
 
         int getPriority() {
-            return priority;
+            return this.priority;
+        }
+
+        long getOrder() {
+            return this.order;
         }
 
-        PriorityRunnable(int priority) {
+        PriorityRunnable(int priority, long order) {
             this.priority = priority;
+            this.order = order;
         }
 
         @Override

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

@@ -1161,9 +1161,9 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                                     Integer p2 = k2.getPriority();
                                                     int priority = p1.compareTo(p2);
                                                     if (priority == 0) {
-                                                        Long t1 = k1.getTime();
-                                                        Long t2 = k2.getTime();
-                                                        return t1.compareTo(t2);
+                                                        Long o1 = k1.getOrder();
+                                                        Long o2 = k2.getOrder();
+                                                        return o1.compareTo(o2);
                                                     } else
                                                         return priority;
                                                 }
@@ -1177,7 +1177,7 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                                 }
 
                                                 try {
-                                                    executor.submit(new Helper.PriorityRunnable(key.getPriority()) {
+                                                    executor.submit(new Helper.PriorityRunnable(key.getPriority(), key.getOrder()) {
                                                         @Override
                                                         public void run() {
                                                             super.run();

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

@@ -48,7 +48,7 @@ public class TupleOperationEx extends EntityOperation {
     PartitionKey getPartitionKey(boolean offline) {
         PartitionKey key = new PartitionKey();
 
-        key.time = this.created;
+        key.order = this.id;
 
         if (offline) {
             // open/close folder is expensive
@@ -75,13 +75,13 @@ public class TupleOperationEx extends EntityOperation {
     }
 
     class PartitionKey {
-        public long time;
+        private long order;
         private int priority;
         private String id;
         private String operation;
 
-        long getTime() {
-            return time;
+        long getOrder() {
+            return this.order;
         }
 
         int getPriority() {