delivery ack added

client/helpers/bgPollHelper.go

@@ -2,6 +2,7 @@ package helpers
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -179,8 +180,15 @@ func ConsumeInboxFile(messageFilename string) ([]string, []string, string, error
 			}
 			filenames = []string{}
 
+		// Send delivery ack if the peer requested it
+		if peer.SendDeliveryAck && usermsg.Status != nil && usermsg.Status.Uuid != "" {
+			storagePath := filepath.Join(client.GetConfig().StoragePath, identity.Uuid)
+			if ackErr := sendDeliveryAck(storagePath, peer, usermsg.Status.Uuid); ackErr != nil {
+				logger.Warn().Err(ackErr).Str("peer", peer.Uid).Msg("ConsumeInboxFile: sendDeliveryAck")
+			}
 		}
 	}
+	}
 
 	err = os.Remove(messageFilename)
 	if err != nil {
@@ -240,3 +248,45 @@ func LongPollAllServerJobs(storage_path string, jobs []client.RequestsJob, timeo
 	}
 
 }
+
+// sendDeliveryAck builds a delivery acknowledgment for messageUuid and enqueues
+// it for sending to the peer's contact pull servers.
+func sendDeliveryAck(storagePath string, peer *client.Peer, messageUuid string) error {
+	packedMsg, _, err := BuildReceivedMessage(messageUuid, peer.Uid, time.Now().UTC().Unix())
+	if err != nil {
+		return fmt.Errorf("sendDeliveryAck: BuildReceivedMessage: %w", err)
+	}
+
+	data, err := proto.Marshal(packedMsg)
+	if err != nil {
+		return fmt.Errorf("sendDeliveryAck: proto.Marshal: %w", err)
+	}
+
+	outboxDir := filepath.Join(storagePath, "outbox")
+	if err := os.MkdirAll(outboxDir, 0700); err != nil {
+		return fmt.Errorf("sendDeliveryAck: MkdirAll: %w", err)
+	}
+
+	outboxFile := filepath.Join(outboxDir, "ack_"+uuid.New().String())
+	if err := os.WriteFile(outboxFile, data, 0600); err != nil {
+		return fmt.Errorf("sendDeliveryAck: WriteFile: %w", err)
+	}
+
+	var servers []client.Server
+	for _, srvUid := range peer.ContactPullServers {
+		srv, loadErr := client.GetConfig().GetIdentity().MessageServers.LoadServer(srvUid)
+		if loadErr == nil && srv != nil {
+			servers = append(servers, *srv)
+		}
+	}
+	if len(servers) == 0 {
+		os.Remove(outboxFile)
+		return errors.New("sendDeliveryAck: no contact servers found")
+	}
+
+	return client.PushSendJob(storagePath, &client.SendJob{
+		Queue:   peer.Uid,
+		File:    outboxFile,
+		Servers: servers,
+	})
+}