Outgoing Read Receipts

// FREEBIE

src/Devices/OWSReadReceiptObserver.h

@@ -0,0 +1,14 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class TSMessagesManager;
+
+@interface OWSReadReceiptObserver : NSObject
+
+- (instancetype)initWithMessagesManager:(TSMessagesManager *)messagesManager;
+- (void)startObserving;
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptObserver.m

@@ -0,0 +1,110 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+#import "OWSReadReceiptObserver.h"
+#import "OWSReadReceipt.h"
+#import "OWSReadReceiptsMessage.h"
+#import "TSContactThread.h"
+#import "TSIncomingMessage.h"
+#import "TSMessagesManager+sendMessages.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface OWSReadReceiptObserver ()
+
+@property (atomic) NSMutableArray<OWSReadReceipt *> *readReceiptsQueue;
+@property (nonatomic, readonly) TSMessagesManager *messagesManager;
+@property BOOL isObserving;
+
+@end
+
+@implementation OWSReadReceiptObserver
+
+- (instancetype)initWithMessagesManager:(TSMessagesManager *)messagesManager
+{
+    self = [super init];
+    if (!self) {
+        return self;
+    }
+
+    _readReceiptsQueue = [NSMutableArray new];
+    _messagesManager = messagesManager;
+    _isObserving = NO;
+
+    return self;
+}
+
+- (void)startObserving
+{
+    if (self.isObserving) {
+        return;
+    }
+
+    self.isObserving = true;
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(handleReadNotification:)
+                                                 name:TSIncomingMessageWasReadOnThisDeviceNotification
+                                               object:nil];
+}
+
+- (void)handleReadNotification:(NSNotification *)notification
+{
+    if (![notification.object isKindOfClass:[TSIncomingMessage class]]) {
+        DDLogError(@"Read receipt notifier got unexpected object: %@", notification.object);
+        return;
+    }
+
+    TSIncomingMessage *message = (TSIncomingMessage *)notification.object;
+
+    // Only groupthread sets authorId, thus this crappy code.
+    // TODO ALL incoming messages should have an authorId.
+    NSString *messageAuthorId;
+    if (message.authorId) { // Group Thread
+        messageAuthorId = message.authorId;
+    } else { // Contact Thread
+        messageAuthorId = [TSContactThread contactIdFromThreadId:message.uniqueThreadId];
+    }
+
+    OWSReadReceipt *readReceipt = [[OWSReadReceipt alloc] initWithSenderId:messageAuthorId timestamp:message.timestamp];
+    [self.readReceiptsQueue addObject:readReceipt];
+
+    // Wait a bit to bundle up read receipts into one request.
+    __weak typeof(self) weakSelf = self;
+    [weakSelf performSelector:@selector(sendAllReadReceiptsInQueue) withObject:nil afterDelay:2.0];
+}
+
+- (void)sendAllReadReceiptsInQueue
+{
+    // Synchronized so we don't lose any read receipts while replacing the queue
+    __block NSArray<OWSReadReceipt *> *receiptsToSend;
+    @synchronized(self)
+    {
+        if (self.readReceiptsQueue.count > 0) {
+            receiptsToSend = [self.readReceiptsQueue copy];
+            self.readReceiptsQueue = [NSMutableArray new];
+        }
+    }
+
+    if (receiptsToSend) {
+        [self sendReadReceipts:receiptsToSend];
+    } else {
+        DDLogVerbose(@"Read receipts queue already drained.");
+    }
+}
+
+- (void)sendReadReceipts:(NSArray<OWSReadReceipt *> *)readReceipts
+{
+    OWSReadReceiptsMessage *message = [[OWSReadReceiptsMessage alloc] initWithReadReceipts:readReceipts];
+
+    [self.messagesManager sendMessage:message
+        inThread:nil
+        success:^{
+            DDLogInfo(@"Successfully sent %ld read receipt", (unsigned long)readReceipts.count);
+        }
+        failure:^{
+            DDLogError(@"Failed to send read receipt");
+        }];
+}
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptsMessage.h

@@ -0,0 +1,15 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+#import "OWSOutgoingSyncMessage.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class OWSReadReceipt;
+
+@interface OWSReadReceiptsMessage : OWSOutgoingSyncMessage
+
+- (instancetype)initWithReadReceipts:(NSArray<OWSReadReceipt *> *)readReceipts;
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptsMessage.m

@@ -0,0 +1,45 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+#import "OWSReadReceiptsMessage.h"
+#import "OWSReadReceipt.h"
+#import "OWSSignalServiceProtos.pb.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface OWSReadReceiptsMessage ()
+
+@property (nonatomic, readonly) NSArray<OWSReadReceipt *> *readReceipts;
+
+@end
+
+@implementation OWSReadReceiptsMessage
+
+- (instancetype)initWithReadReceipts:(NSArray<OWSReadReceipt *> *)readReceipts
+{
+    self = [super init];
+    if (!self) {
+        return self;
+    }
+
+    _readReceipts = [readReceipts copy];
+
+    return self;
+}
+
+- (OWSSignalServiceProtosSyncMessage *)buildSyncMessage
+{
+    OWSSignalServiceProtosSyncMessageBuilder *syncMessageBuilder = [OWSSignalServiceProtosSyncMessageBuilder new];
+    for (OWSReadReceipt *readReceipt in self.readReceipts) {
+        OWSSignalServiceProtosSyncMessageReadBuilder *readProtoBuilder =
+            [OWSSignalServiceProtosSyncMessageReadBuilder new];
+        [readProtoBuilder setSender:readReceipt.senderId];
+        [readProtoBuilder setTimestamp:readReceipt.timestamp];
+        [syncMessageBuilder addRead:[readProtoBuilder build]];
+    }
+
+    return [syncMessageBuilder build];
+}
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptsProcessor.m

@@ -45,13 +45,15 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)process
 {
-    DDLogInfo(@"Processing %ld read receipts.", self.readReceipts.count);
+    DDLogInfo(@"Processing %ld read receipts.", (unsigned long)self.readReceipts.count);
     for (OWSReadReceipt *readReceipt in self.readReceipts) {
         TSIncomingMessage *message =
             [TSIncomingMessage findMessageWithAuthorId:readReceipt.senderId timestamp:readReceipt.timestamp];
         if (message) {
-            [message markAsRead];
+            [message markAsReadFromReadReceipt];
         } else {
+            // TODO keep read receipts around so that if we get the receipt before the message,
+            //      we can immediately mark the message as read once we get it.
             DDLogWarn(@"Couldn't find message for read receipt. Message not synced?");
         }
     }

src/Messages/DeviceSyncing/OWSOutgoingSyncMessage.m

@@ -7,6 +7,13 @@ NS_ASSUME_NONNULL_BEGIN
 
 @implementation OWSOutgoingSyncMessage
 
+- (void)saveWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
+{
+    // override superclass with no-op.
+    //
+    // There's no need to save this message, since it's not displayed to the user.
+}
+
 - (BOOL)shouldSyncTranscript
 {
     return NO;

src/Messages/DeviceSyncing/OWSSyncContactsMessage.h

@@ -10,7 +10,6 @@ NS_ASSUME_NONNULL_BEGIN
 @interface OWSSyncContactsMessage : OWSOutgoingSyncMessage
 
 - (instancetype)initWithContactsManager:(id<ContactsManagerProtocol>)contactsManager;
-- (void)saveWithTransaction:(YapDatabaseReadWriteTransaction *)transaction;
 - (NSData *)buildPlainTextAttachmentData;
 
 @end

src/Messages/DeviceSyncing/OWSSyncGroupsMessage.h

@@ -6,7 +6,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface OWSSyncGroupsMessage : OWSOutgoingSyncMessage
 
-- (void)saveWithTransaction:(YapDatabaseReadWriteTransaction *)transaction;
 - (NSData *)buildPlainTextAttachmentData;
 
 @end

src/Messages/DeviceSyncing/OWSSyncGroupsMessage.m

@@ -17,14 +17,6 @@ NS_ASSUME_NONNULL_BEGIN
     return [super initWithTimestamp:[NSDate ows_millisecondTimeStamp]];
 }
 
-- (void)saveWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
-{
-    // no-op
-
-    // There's no need to save this message, since it's not displayed to the user.
-    // Furthermore if we did save it, we probably don't want to save the conctactsManager property.
-}
-
 - (OWSSignalServiceProtosSyncMessage *)buildSyncMessage
 {
 

src/Messages/Interactions/TSIncomingMessage.h

@@ -8,6 +8,8 @@ NS_ASSUME_NONNULL_BEGIN
 @class TSContactThread;
 @class TSGroupThread;
 
+extern NSString *const TSIncomingMessageWasReadOnThisDeviceNotification;
+
 @interface TSIncomingMessage : TSMessage
 
 /**
@@ -104,11 +106,17 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, readonly) NSDate *receivedAt;
 
 /*
- * Marks a message as having been read and broadcasts a TSIncomingMessageWasReadNotification
+ * Marks a message as having been read on this device (as opposed to responding to a remote read receipt).
+ *
  */
-- (void)markAsRead;
 - (void)markAsReadWithTransaction:(YapDatabaseReadWriteTransaction *)transaction;
 
+/**
+ * Similar to markAsReadWithTransaction, but doesn't send out read receipts.
+ * Used for *responding* to a remote read receipt.
+ */
+- (void)markAsReadFromReadReceipt;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/Interactions/TSIncomingMessage.m

@@ -9,6 +9,8 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+NSString *const TSIncomingMessageWasReadOnThisDeviceNotification = @"TSIncomingMessageWasReadOnThisDeviceNotification";
+
 @implementation TSIncomingMessage
 
 - (instancetype)initWithTimestamp:(uint64_t)timestamp
@@ -98,14 +100,21 @@ NS_ASSUME_NONNULL_BEGIN
     return foundMessage;
 }
 
-- (void)markAsRead
+- (void)markAsReadFromReadReceipt
 {
     [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
-        [self markAsReadWithTransaction:transaction];
+        [self markAsReadWithoutNotificationWithTransaction:transaction];
     }];
 }
 
 - (void)markAsReadWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
+{
+    [self markAsReadWithoutNotificationWithTransaction:transaction];
+    [[NSNotificationCenter defaultCenter] postNotificationName:TSIncomingMessageWasReadOnThisDeviceNotification
+                                                        object:self];
+}
+
+- (void)markAsReadWithoutNotificationWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
 {
     _read = YES;
     [self saveWithTransaction:transaction];

src/Messages/TSMessagesManager.m

@@ -69,7 +69,7 @@
                 DDLogWarn(@"Received an unknown message type");
                 break;
             default:
-                DDLogWarn(@"Received unhandled envelope type: %d", envelope.type);
+                DDLogWarn(@"Received unhandled envelope type: %d", (int)envelope.type);
                 break;
         }
     } @catch (NSException *exception) {