Error handling messages and Info Messages

Signal/src/textsecure/Messages/TSErrorMessage.m

@@ -12,7 +12,7 @@
 @implementation TSErrorMessage
 
 - (instancetype)initWithTimestamp:(uint64_t)timestamp inThread:(TSThread *)thread failedMessageType:(TSErrorMessageType)errorMessageType{
-    self = [super initWithTimestamp:timestamp inThread:thread messageBody:@"Placeholder for error message." attachements:nil];
+    self = [super initWithTimestamp:timestamp inThread:thread messageBody:nil attachements:nil];
     
     if (self) {
         _errorType = errorMessageType;
@@ -21,6 +21,28 @@
     return self;
 }
 
+- (NSString*)description{
+    switch (_errorType) {
+        case TSErrorMessageNoSession:
+            return @"No available session for contact";
+        case TSErrorMessageMissingKeyId:
+            return @"Received a message with unknown PreKey";
+        case TSErrorMessageInvalidMessage:
+            return @"Received a corrupted message";
+        case TSErrorMessageInvalidVersion:
+            return @"Received a message not compatible with this version";
+        case TSErrorMessageDuplicateMessage:
+            return @"Received a duplicated message";
+        case TSErrorMessageInvalidKeyException:
+            return @"The recipient's key is not valid.";
+        case TSErrorMessageWrongTrustedIdentityKey:
+            return @"Your contact's identity key changed. Tap to verify and accept new key";
+        default:
+            return @"An unknown error occured";
+            break;
+    }
+}
+
 + (instancetype)userNotRegisteredErrorMessageInThread:(TSThread*)thread{
     return [[self alloc] initWithTimestamp:[NSDate ows_millisecondTimeStamp] inThread:thread];
 }

Signal/src/textsecure/Messages/TSInfoMessage.h

@@ -11,7 +11,8 @@
 @interface TSInfoMessage : TSMessage
 
 typedef NS_ENUM(NSInteger, TSInfoMessageType){
-    TSInfoMessageTypeSessionDidEnd
+    TSInfoMessageTypeSessionDidEnd,
+    TSInfoMessageTypeUnsupportedMessage
 };
 
 @property TSInfoMessageType messageType;

Signal/src/textsecure/Messages/TSInfoMessage.m

@@ -20,4 +20,17 @@
     return self;
 }
 
+- (NSString *)description{
+    switch (_messageType) {
+        case TSInfoMessageTypeSessionDidEnd:
+            return @"Secure session ended.";
+        case TSInfoMessageTypeUnsupportedMessage:
+            return @"Media messages are currently not supported.";
+        default:
+            break;
+    }
+    
+    return @"Unknown Info Message Type";
+}
+
 @end

Signal/src/textsecure/Messages/TSMessagesManager.m

@@ -180,6 +180,13 @@
     } else if (content.attachments.count > 0) {
         DDLogVerbose(@"Received push media message (attachement) ...");
         [self handleReceivedMediaMessage:incomingMessage withContent:content];
+        [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+            TSInfoMessage *message = [[TSInfoMessage alloc] initWithTimestamp:incomingMessage.timestamp
+                                                                     inThread:[TSContactThread threadWithContactId:incomingMessage.source transaction:transaction]
+                                                                  messageType:TSInfoMessageTypeUnsupportedMessage];
+            [message saveWithTransaction:transaction];
+        }];
+        
     } else {
         DDLogVerbose(@"Received push text message...");
         [self handleReceivedTextMessage:incomingMessage withContent:content];
@@ -231,7 +238,7 @@
 }
 
 - (void)processException:(NSException*)exception pushSignal:(IncomingPushMessageSignal*)signal{
-    NSLog(@"Got exception: %@", exception.description);
+    DDLogError(@"Got exception: %@", exception.description);
     [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
         TSErrorMessage *errorMessage = [[TSErrorMessage alloc] initWithTimestamp:signal.timestamp inThread:[TSContactThread threadWithContactId:signal.source transaction:transaction] failedMessageType:TSErrorMessageNoSession];
         [errorMessage saveWithTransaction:transaction];

Signal/src/view controllers/MessagesViewController.m

@@ -165,16 +165,17 @@ typedef enum : NSUInteger {
 
 -(void)initializeCollectionViewLayout
 {
-    [self.collectionView.collectionViewLayout setMessageBubbleFont:[UIFont ows_lightFontWithSize:16.0f]];
+    if (self.collectionView){
+        [self.collectionView.collectionViewLayout setMessageBubbleFont:[UIFont ows_lightFontWithSize:16.0f]];
         
-    self.collectionView.showsVerticalScrollIndicator = NO;
-    self.collectionView.showsHorizontalScrollIndicator = NO;
+        self.collectionView.showsVerticalScrollIndicator = NO;
+        self.collectionView.showsHorizontalScrollIndicator = NO;
         
-    self.automaticallyScrollsToMostRecentMessage = YES;
-    
-    self.collectionView.collectionViewLayout.incomingAvatarViewSize = CGSizeZero;
-    self.collectionView.collectionViewLayout.outgoingAvatarViewSize = CGSizeZero;
+        self.automaticallyScrollsToMostRecentMessage = YES;
         
+        self.collectionView.collectionViewLayout.incomingAvatarViewSize = CGSizeZero;
+        self.collectionView.collectionViewLayout.outgoingAvatarViewSize = CGSizeZero;
+    }
 }
 
 #pragma mark - Fingerprints
@@ -190,7 +191,7 @@ typedef enum : NSUInteger {
 
 -(BOOL)isRedPhoneReachable
 {
-   return [[Environment getCurrent].contactsManager isPhoneNumberRegisteredWithRedPhone:[self phoneNumberForThread]];
+    return [[Environment getCurrent].contactsManager isPhoneNumberRegisteredWithRedPhone:[self phoneNumberForThread]];
 }
 
 -(PhoneNumber*)phoneNumberForThread