Pad NonceResyncableMessageBlock with GetStatusCommands to ensure > 1 packet in order to improve command verification

app/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/comm/OmnipodCommunicationService.java

@@ -148,7 +148,20 @@ public class OmnipodCommunicationService extends RileyLinkCommunicationManager {
         }
 
         boolean firstPacket = true;
-        byte[] encodedMessage = message.getEncoded();
+        byte[] encodedMessage;
+        if (message.isNonceResyncable()) {
+            OmnipodMessage paddedMessage = new OmnipodMessage(message);
+            // If messages are nonce resyncable, we want do distinguish between certain and uncertain failures for verification purposes
+            // However, some commands (e.g. cancel delivery) are single packet command by nature. When we get a timeout with a single packet,
+            // we are unsure whether or not the command was received by the pod
+            // However, if we send > 1 packet, we know that the command wasn't received if we never send the subsequent packets,
+            // because the last packet contains the CRC.
+            // So we pad the message with get status commands to make it > packet
+            paddedMessage.padWithGetStatusCommands(PacketType.PDM.getMaxBodyLength()); // First packet is of type PDM
+            encodedMessage = paddedMessage.getEncoded();
+        } else {
+            encodedMessage = message.getEncoded();
+        }
 
         OmnipodPacket response = null;
         while (encodedMessage.length > 0) {

app/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/comm/OmnipodManager.java

@@ -221,18 +221,6 @@ public class OmnipodManager {
 
         logStartingCommandExecution("cancelDelivery [deliveryTypes=" + deliveryTypes + ", acknowledgementBeep=" + acknowledgementBeep + "]");
 
-        try {
-            // As the cancel delivery command is a single packet command,
-            // first verify that the pod is reachable by obtaining a status response
-            // FIXME replace this with padding the CancelDelivery command message
-            //  with GetStatusResponse commands to ensure that the message > 1 packets
-            StatusResponse podStatus = getPodStatus();
-        } catch (OmnipodException ex) {
-            logCommandExecutionFinished("cancelDelivery");
-            ex.setCertainFailure(true);
-            throw ex;
-        }
-
         try {
             executeAndVerify(() -> communicationService.executeAction(new CancelDeliveryAction(podState, deliveryTypes, acknowledgementBeep)));
         } finally {

app/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/comm/message/OmnipodMessage.java

@@ -1,14 +1,12 @@
 package info.nightscout.androidaps.plugins.pump.omnipod.comm.message;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.util.ArrayList;
 import java.util.List;
 
 import info.nightscout.androidaps.plugins.pump.common.utils.ByteUtil;
-import info.nightscout.androidaps.plugins.pump.omnipod.comm.OmnipodCommunicationService;
+import info.nightscout.androidaps.plugins.pump.omnipod.comm.message.command.GetStatusCommand;
 import info.nightscout.androidaps.plugins.pump.omnipod.defs.MessageBlockType;
+import info.nightscout.androidaps.plugins.pump.omnipod.defs.PodInfoType;
 import info.nightscout.androidaps.plugins.pump.omnipod.exception.CrcMismatchException;
 import info.nightscout.androidaps.plugins.pump.omnipod.exception.MessageDecodingException;
 import info.nightscout.androidaps.plugins.pump.omnipod.exception.NotEnoughDataException;
@@ -16,11 +14,16 @@ import info.nightscout.androidaps.plugins.pump.omnipod.util.OmniCRC;
 
 public class OmnipodMessage {
 
-    private static final Logger LOG = LoggerFactory.getLogger(OmnipodCommunicationService.class);
     private final int address;
     private final List<MessageBlock> messageBlocks;
     private final int sequenceNumber;
 
+    public OmnipodMessage(OmnipodMessage other) {
+        address = other.address;
+        messageBlocks = new ArrayList<>(other.messageBlocks);
+        sequenceNumber = other.sequenceNumber;
+    }
+
     public OmnipodMessage(int address, List<MessageBlock> messageBlocks, int sequenceNumber) {
         this.address = address;
         this.messageBlocks = messageBlocks;
@@ -88,6 +91,12 @@ public class OmnipodMessage {
         return encodedData;
     }
 
+    public void padWithGetStatusCommands(int packetSize) {
+        while (getEncoded().length < packetSize) {
+            messageBlocks.add(new GetStatusCommand(PodInfoType.NORMAL));
+        }
+    }
+
     public List<MessageBlock> getMessageBlocks() {
         return messageBlocks;
     }
@@ -106,14 +115,21 @@ public class OmnipodMessage {
     }
 
     public boolean isNonceResyncable() {
-        return messageBlocks.size() > 0 && (messageBlocks.get(0) instanceof NonceResyncableMessageBlock);
+        for (MessageBlock messageBlock : messageBlocks) {
+            if (messageBlock instanceof NonceResyncableMessageBlock) {
+                return true;
+            }
+        }
+        return false;
     }
 
     public int getSentNonce() {
-        if (!isNonceResyncable()) {
+        for (MessageBlock messageBlock : messageBlocks) {
-            throw new UnsupportedOperationException("Message is not nonce resyncable");
+            if (messageBlock instanceof NonceResyncableMessageBlock) {
+                return ((NonceResyncableMessageBlock) messageBlock).getNonce();
+            }
         }
-        return ((NonceResyncableMessageBlock) messageBlocks.get(0)).getNonce();
+        throw new UnsupportedOperationException("Message is not nonce resyncable");
     }
 
     public void resyncNonce(int nonce) {