Incoming Read Receipts

// FREEBIE

src/Contacts/TSThread.m

@@ -178,8 +178,7 @@ NS_ASSUME_NONNULL_BEGIN
                   }];
 
     for (TSIncomingMessage *message in array) {
-        message.read = YES;
-        [message saveWithTransaction:transaction];
+        [message markAsReadWithTransaction:transaction];
     }
 }
 

src/Contacts/Threads/TSContactThread.h

@@ -18,6 +18,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (NSString *)contactIdentifier;
 
++ (NSString *)contactIdFromThreadId:(NSString *)threadId;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceipt.h

@@ -0,0 +1,16 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface OWSReadReceipt : NSObject
+
+@property (nonatomic, readonly) NSString *senderId;
+@property (nonatomic, readonly) uint64_t timestamp;
+@property (nonatomic, readonly, getter=isValid) BOOL valid;
+@property (nonatomic, readonly) NSArray<NSString *> *validationErrorMessages;
+
+- (instancetype)initWithSenderId:(NSString *)senderId timestamp:(uint64_t)timestamp;
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceipt.m

@@ -0,0 +1,35 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+#import "OWSReadReceipt.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@implementation OWSReadReceipt
+
+- (instancetype)initWithSenderId:(NSString *)senderId timestamp:(uint64_t)timestamp;
+{
+    self = [super init];
+    if (!self) {
+        return self;
+    }
+
+    NSMutableArray<NSString *> *validationErrorMessage = [NSMutableArray new];
+    if (!senderId) {
+        [validationErrorMessage addObject:@"Must specify sender id"];
+    }
+    _senderId = senderId;
+
+    if (!timestamp) {
+        [validationErrorMessage addObject:@"Must specify timestamp"];
+    }
+    _timestamp = timestamp;
+
+    _valid = validationErrorMessage.count == 0;
+    _validationErrorMessages = [validationErrorMessage copy];
+
+    return self;
+}
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptsProcessor.h

@@ -0,0 +1,15 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class OWSSignalServiceProtosSyncMessageRead;
+
+@interface OWSReadReceiptsProcessor : NSObject
+
+- (instancetype)initWithReadReceiptProtos:(NSArray<OWSSignalServiceProtosSyncMessageRead *> *)readReceiptProtos
+    NS_DESIGNATED_INITIALIZER;
+- (void)process;
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Devices/OWSReadReceiptsProcessor.m

@@ -0,0 +1,62 @@
+//  Copyright © 2016 Open Whisper Systems. All rights reserved.
+
+#import "OWSReadReceiptsProcessor.h"
+#import "OWSReadReceipt.h"
+#import "OWSSignalServiceProtos.pb.h"
+#import "TSIncomingMessage.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface OWSReadReceiptsProcessor ()
+
+@property (nonatomic, readonly) NSArray<OWSReadReceipt *> *readReceipts;
+
+@end
+
+@implementation OWSReadReceiptsProcessor
+
+- (instancetype)init
+{
+    return [self initWithReadReceiptProtos:@[]];
+}
+
+- (instancetype)initWithReadReceiptProtos:(NSArray<OWSSignalServiceProtosSyncMessageRead *> *)readReceiptProtos
+{
+    self = [super init];
+    if (!self) {
+        return self;
+    }
+
+    NSMutableArray<OWSReadReceipt *> *readReceipts = [NSMutableArray new];
+    for (OWSSignalServiceProtosSyncMessageRead *readReceiptProto in readReceiptProtos) {
+        OWSReadReceipt *readReceipt =
+            [[OWSReadReceipt alloc] initWithSenderId:readReceiptProto.sender timestamp:readReceiptProto.timestamp];
+        if (readReceipt.isValid) {
+            [readReceipts addObject:readReceipt];
+        } else {
+            DDLogError(@"Received invalid read receipt: %@", readReceipt.validationErrorMessages);
+        }
+    }
+
+    _readReceipts = [readReceipts copy];
+
+    return self;
+}
+
+- (void)process
+{
+    DDLogInfo(@"Processing %ld read receipts.", self.readReceipts.count);
+    for (OWSReadReceipt *readReceipt in self.readReceipts) {
+        TSIncomingMessage *message =
+            [TSIncomingMessage findMessageWithAuthorId:readReceipt.senderId timestamp:readReceipt.timestamp];
+        if (message) {
+            [message markAsRead];
+        } else {
+            DDLogWarn(@"Couldn't find message for read receipt. Message not synced?");
+        }
+    }
+}
+
+@end
+
+NS_ASSUME_NONNULL_END

src/Messages/Interactions/TSIncomingMessage.h

@@ -88,10 +88,27 @@ NS_ASSUME_NONNULL_BEGIN
                       messageBody:(nullable NSString *)body
                     attachmentIds:(NSArray<NSString *> *)attachmentIds;
 
+/*
+ * Find a message matching the senderId and timestamp, if any.
+ *
+ * @param authorId
+ *   Signal ID (i.e. e164) of the user who sent the message
+ * @params timestamp
+ *   When the message was created in milliseconds since epoch
+ *
+ */
++ (nullable instancetype)findMessageWithAuthorId:(NSString *)authorId timestamp:(uint64_t)timestamp;
+
 @property (nonatomic, readonly) NSString *authorId;
-@property (nonatomic, getter=wasRead) BOOL read;
+@property (nonatomic, readonly, getter=wasRead) BOOL read;
 @property (nonatomic, readonly) NSDate *receivedAt;
 
+/*
+ * Marks a message as having been read and broadcasts a TSIncomingMessageWasReadNotification
+ */
+- (void)markAsRead;
+- (void)markAsReadWithTransaction:(YapDatabaseReadWriteTransaction *)transaction;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/Interactions/TSIncomingMessage.m

@@ -3,7 +3,9 @@
 
 #import "TSIncomingMessage.h"
 #import "TSContactThread.h"
+#import "TSDatabaseSecondaryIndexes.h"
 #import "TSGroupThread.h"
+#import <YapDatabase/YapDatabaseConnection.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -61,6 +63,55 @@ NS_ASSUME_NONNULL_BEGIN
     return self;
 }
 
++ (nullable instancetype)findMessageWithAuthorId:(NSString *)authorId timestamp:(uint64_t)timestamp
+{
+    __block TSIncomingMessage *foundMessage;
+    [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+        // In theory we could build a new secondaryIndex for (authorId,timestamp), but in practice there should
+        // be *very* few (millisecond) timestamps with multiple authors.
+        [TSDatabaseSecondaryIndexes
+            enumerateMessagesWithTimestamp:timestamp
+                                 withBlock:^(NSString *collection, NSString *key, BOOL *stop) {
+                                     TSInteraction *interaction =
+                                         [TSInteraction fetchObjectWithUniqueID:key transaction:transaction];
+                                     if ([interaction isKindOfClass:[TSIncomingMessage class]]) {
+                                         TSIncomingMessage *message = (TSIncomingMessage *)interaction;
+
+                                         // 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];
+                                         }
+
+                                         if ([messageAuthorId isEqualToString:authorId]) {
+                                             foundMessage = message;
+                                         }
+                                     }
+                                 }
+                          usingTransaction:transaction];
+    }];
+
+    return foundMessage;
+}
+
+- (void)markAsRead
+{
+    [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+        [self markAsReadWithTransaction:transaction];
+    }];
+}
+
+- (void)markAsReadWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
+{
+    _read = YES;
+    [self saveWithTransaction:transaction];
+    [transaction touchObjectForKey:self.uniqueThreadId inCollection:[TSThread collection]];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/TSMessagesManager.m

@@ -6,6 +6,7 @@
 #import "MimeTypeUtil.h"
 #import "NSData+messagePadding.h"
 #import "OWSIncomingSentMessageTranscript.h"
+#import "OWSReadReceiptsProcessor.h"
 #import "OWSSyncContactsMessage.h"
 #import "OWSSyncGroupsMessage.h"
 #import "TSAccountManager.h"
@@ -235,8 +236,7 @@
         OWSIncomingSentMessageTranscript *transcript =
             [[OWSIncomingSentMessageTranscript alloc] initWithProto:syncMessage.sent relay:messageEnvelope.relay];
         [transcript record];
-    }
-    if (syncMessage.hasRequest) {
+    } else if (syncMessage.hasRequest) {
         if (syncMessage.request.type == OWSSignalServiceProtosSyncMessageRequestTypeContacts) {
             DDLogInfo(@"Received request `Contacts` syncMessage.");
 
@@ -270,6 +270,12 @@
                     DDLogError(@"Failed to send Groups response syncMessage.");
                 }];
         }
+    } else if (syncMessage.read.count > 0) {
+        DDLogInfo(@"Received %ld read receipt(s)", (u_long)syncMessage.read.count);
+
+        OWSReadReceiptsProcessor *readReceiptsProcessor =
+            [[OWSReadReceiptsProcessor alloc] initWithReadReceiptProtos:syncMessage.read];
+        [readReceiptsProcessor process];
     } else {
         DDLogWarn(@"Ignoring unsupported sync message.");
     }