Fix disappearing messages don't become consistent after reinstall (#52)

Fixes the bug wherein:

Given the sender had disappearing messages enabled
And the receiver thinks it's disabled (this can happen due to re-install)
When we receive a disappearing message
The message does start expiring timer and disappear
But you see a notice "<sender> disabled disappearing messages"
Rather than the expected "<Sender> set disappearing messages timer to X".

// FREEBIE

src/Contacts/OWSDisappearingMessagesConfiguration.h

@@ -20,7 +20,10 @@ extern const uint32_t OWSDisappearingMessagesConfigurationDefaultExpirationDurat
 @property (nonatomic, readonly) BOOL dictionaryValueDidChange;
 @property (readonly, getter=isNewRecord) BOOL newRecord;
 
++ (instancetype)fetchOrCreateDefaultWithThreadId:(NSString *)threadId;
+
 + (NSArray<NSNumber *> *)validDurationsSeconds;
+
 + (NSString *)stringForDurationSeconds:(uint32_t)durationSeconds;
 
 @end

src/Contacts/OWSDisappearingMessagesConfiguration.m

@@ -49,6 +49,16 @@ const uint32_t OWSDisappearingMessagesConfigurationDefaultExpirationDuration = 6
     return self;
 }
 
++ (instancetype)fetchOrCreateDefaultWithThreadId:(NSString *)threadId
+{
+    OWSDisappearingMessagesConfiguration *savedConfiguration = [self fetchObjectWithUniqueID:threadId];
+    if (savedConfiguration) {
+        return savedConfiguration;
+    } else {
+        return [[self alloc] initDefaultWithThreadId:threadId];
+    }
+}
+
 + (NSString *)stringForDurationSeconds:(uint32_t)durationSeconds
 {
     NSString *amountFormat;

src/Messages/OWSDisappearingMessagesJob.m

@@ -164,7 +164,7 @@ NS_ASSUME_NONNULL_BEGIN
     // Become eventually consistent in the case that the remote changed their settings at the same time.
     // Also in case remote doesn't support expiring messages
     OWSDisappearingMessagesConfiguration *disappearingMessagesConfiguration =
-        [OWSDisappearingMessagesConfiguration fetchObjectWithUniqueID:message.uniqueThreadId];
+        [OWSDisappearingMessagesConfiguration fetchOrCreateDefaultWithThreadId:message.uniqueThreadId];
 
     BOOL changed = NO;
     if (message.expiresInSeconds == 0) {

tests/Messages/OWSDisappearingMessagesJobTest.m

@@ -2,8 +2,10 @@
 //  Copyright © 2016 Open Whisper Systems. All rights reserved.
 
 #import "NSDate+millisecondTimeStamp.h"
+#import "OWSDisappearingMessagesConfiguration.h"
 #import "OWSDisappearingMessagesFinder.h"
 #import "OWSDisappearingMessagesJob.h"
+#import "OWSFakeContactsManager.h"
 #import "TSMessage.h"
 #import "TSStorageManager.h"
 #import "TSThread.h"
@@ -68,6 +70,59 @@ NS_ASSUME_NONNULL_BEGIN
     XCTAssertEqual(2, [TSMessage numberOfKeysInCollection]);
 }
 
+- (void)testBecomeConsistentWithMessageConfiguration
+{
+    TSThread *thread = [[TSThread alloc] initWithUniqueId:@"fake-thread-id"];
+    [thread save];
+
+    OWSDisappearingMessagesJob *job =
+        [[OWSDisappearingMessagesJob alloc] initWithStorageManager:[TSStorageManager sharedManager]];
+
+    OWSDisappearingMessagesConfiguration *configuration =
+        [OWSDisappearingMessagesConfiguration fetchObjectWithUniqueID:thread.uniqueId];
+    [configuration remove];
+
+    TSMessage *expiringMessage = [[TSMessage alloc] initWithTimestamp:1
+                                                             inThread:thread
+                                                          messageBody:@"notYetExpiredMessage"
+                                                        attachmentIds:@[]
+                                                     expiresInSeconds:20
+                                                      expireStartedAt:0];
+    [expiringMessage save];
+
+
+    [job becomeConsistentWithConfigurationForMessage:expiringMessage contactsManager:[OWSFakeContactsManager new]];
+    configuration = [OWSDisappearingMessagesConfiguration fetchObjectWithUniqueID:thread.uniqueId];
+
+    XCTAssertNotNil(configuration);
+    XCTAssert(configuration.isEnabled);
+    XCTAssertEqual(20, configuration.durationSeconds);
+}
+
+- (void)testBecomeConsistentWithUnexpiringMessageConfiguration
+{
+    TSThread *thread = [[TSThread alloc] initWithUniqueId:@"fake-thread-id"];
+    [thread save];
+
+    OWSDisappearingMessagesJob *job =
+        [[OWSDisappearingMessagesJob alloc] initWithStorageManager:[TSStorageManager sharedManager]];
+
+    OWSDisappearingMessagesConfiguration *configuration =
+        [OWSDisappearingMessagesConfiguration fetchObjectWithUniqueID:thread.uniqueId];
+    [configuration remove];
+
+
+    TSMessage *unExpiringMessage = [[TSMessage alloc] initWithTimestamp:1
+                                                               inThread:thread
+                                                            messageBody:@"unexpiringMessage"
+                                                          attachmentIds:@[]
+                                                       expiresInSeconds:0
+                                                        expireStartedAt:0];
+    [unExpiringMessage save];
+    [job becomeConsistentWithConfigurationForMessage:unExpiringMessage contactsManager:[OWSFakeContactsManager new]];
+    XCTAssertNil([OWSDisappearingMessagesConfiguration fetchObjectWithUniqueID:thread.uniqueId]);
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

tests/Messages/OWSMessageSenderTest.m

@@ -2,6 +2,7 @@
 //  Copyright © 2016 Open Whisper Systems. All rights reserved.
 
 #import "Cryptography.h"
+#import "OWSDisappearingMessagesConfiguration.h"
 #import "OWSError.h"
 #import "OWSFakeContactsManager.h"
 #import "OWSFakeContactsUpdater.h"
@@ -173,6 +174,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 @property (nonatomic) TSThread *thread;
 @property (nonatomic) TSOutgoingMessage *expiringMessage;
+@property (nonatomic) TSOutgoingMessage *unexpiringMessage;
 @property (nonatomic) OWSMessageSenderFakeNetworkManager *networkManager;
 @property (nonatomic) OWSMessageSender *successfulMessageSender;
 @property (nonatomic) OWSMessageSender *unsuccessfulMessageSender;
@@ -191,6 +193,13 @@ NS_ASSUME_NONNULL_BEGIN
     self.thread = [[TSContactThread alloc] initWithUniqueId:@"fake-thread-id"];
     [self.thread save];
 
+    self.unexpiringMessage = [[TSOutgoingMessage alloc] initWithTimestamp:1
+                                                                 inThread:self.thread
+                                                              messageBody:@"outgoing message"
+                                                            attachmentIds:[NSMutableArray new]
+                                                         expiresInSeconds:0];
+    [self.unexpiringMessage save];
+
     self.expiringMessage = [[TSOutgoingMessage alloc] initWithTimestamp:1
                                                                inThread:self.thread
                                                             messageBody:@"outgoing message"
@@ -217,8 +226,11 @@ NS_ASSUME_NONNULL_BEGIN
                                                                       contactsUpdater:contactsUpdater];
 }
 
-- (void)testExpiringMessageTimerStartsOnSuccess
+- (void)testExpiringMessageTimerStartsOnSuccessWhenDisappearingMessagesEnabled
 {
+    [[[OWSDisappearingMessagesConfiguration alloc] initWithThreadId:self.thread.uniqueId enabled:YES durationSeconds:10]
+        save];
+
     OWSMessageSender *messageSender = self.successfulMessageSender;
 
     // Sanity Check
@@ -243,6 +255,32 @@ NS_ASSUME_NONNULL_BEGIN
                                  }];
 }
 
+- (void)testExpiringMessageTimerDoesNotStartsWhenDisabled
+{
+    [[[OWSDisappearingMessagesConfiguration alloc] initWithThreadId:self.thread.uniqueId enabled:NO durationSeconds:10]
+        save];
+
+    OWSMessageSender *messageSender = self.successfulMessageSender;
+
+    XCTestExpectation *messageDidNotStartExpiration = [self expectationWithDescription:@"messageDidNotStartExpiration"];
+    [messageSender sendMessage:self.unexpiringMessage
+        success:^() {
+            if (self.unexpiringMessage.isExpiringMessage || self.unexpiringMessage.expiresAt > 0) {
+                XCTFail(@"Message expiration was not supposed to start.");
+            } else {
+                [messageDidNotStartExpiration fulfill];
+            }
+        }
+        failure:^(NSError *error) {
+            XCTFail(@"Message failed to send");
+        }];
+
+    [self waitForExpectationsWithTimeout:5
+                                 handler:^(NSError *error) {
+                                     NSLog(@"Expiration timer not set in time.");
+                                 }];
+}
+
 - (void)testExpiringMessageTimerDoesNotStartsOnFailure
 {
     OWSMessageSender *messageSender = self.unsuccessfulMessageSender;