Mention by display name rather than hex encoded public key

Signal.xcodeproj/project.pbxproj

@@ -567,6 +567,7 @@
 		B82584A02315024B001B41CB /* RSSFeedPoller.swift in Sources */ = {isa = PBXBuildFile; fileRef = B825849F2315024B001B41CB /* RSSFeedPoller.swift */; };
 		B845B4D4230CD09100D759F0 /* GroupChatPoller.swift in Sources */ = {isa = PBXBuildFile; fileRef = B845B4D3230CD09000D759F0 /* GroupChatPoller.swift */; };
 		B846365B22B7418B00AF1514 /* Identicon+ObjC.swift in Sources */ = {isa = PBXBuildFile; fileRef = B846365A22B7418B00AF1514 /* Identicon+ObjC.swift */; };
+		B84664F3234FE4540083A1CD /* Mention.swift in Sources */ = {isa = PBXBuildFile; fileRef = B84664F2234FE4530083A1CD /* Mention.swift */; };
 		B86BD08123399883000F5AE3 /* QRCodeModal.swift in Sources */ = {isa = PBXBuildFile; fileRef = B86BD08023399883000F5AE3 /* QRCodeModal.swift */; };
 		B86BD08423399ACF000F5AE3 /* Modal.swift in Sources */ = {isa = PBXBuildFile; fileRef = B86BD08323399ACF000F5AE3 /* Modal.swift */; };
 		B86BD08623399CEF000F5AE3 /* SeedModal.swift in Sources */ = {isa = PBXBuildFile; fileRef = B86BD08523399CEF000F5AE3 /* SeedModal.swift */; };
@@ -1378,6 +1379,7 @@
 		B825849F2315024B001B41CB /* RSSFeedPoller.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RSSFeedPoller.swift; sourceTree = "<group>"; };
 		B845B4D3230CD09000D759F0 /* GroupChatPoller.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GroupChatPoller.swift; sourceTree = "<group>"; };
 		B846365A22B7418B00AF1514 /* Identicon+ObjC.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Identicon+ObjC.swift"; sourceTree = "<group>"; };
+		B84664F2234FE4530083A1CD /* Mention.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Mention.swift; sourceTree = "<group>"; };
 		B86BD08023399883000F5AE3 /* QRCodeModal.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = QRCodeModal.swift; sourceTree = "<group>"; };
 		B86BD08323399ACF000F5AE3 /* Modal.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Modal.swift; sourceTree = "<group>"; };
 		B86BD08523399CEF000F5AE3 /* SeedModal.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SeedModal.swift; sourceTree = "<group>"; };
@@ -2652,6 +2654,7 @@
 				B8162F0222891AD600D46544 /* FriendRequestView.swift */,
 				B8162F0422892C5F00D46544 /* FriendRequestViewDelegate.swift */,
 				24A830A12293CD0100F4CAC0 /* LokiP2PServer.swift */,
+				B84664F2234FE4530083A1CD /* Mention.swift */,
 				B89841E222B7579F00B1BDC6 /* NewConversationVC.swift */,
 				B8258491230FA5DA001B41CB /* ScanQRCodeVC.h */,
 				B8258492230FA5E9001B41CB /* ScanQRCodeVC.m */,
@@ -3879,6 +3882,7 @@
 				345BC30C2047030700257B7C /* OWS2FASettingsViewController.m in Sources */,
 				340FC8B7204DAC8D007AEB0F /* OWSConversationSettingsViewController.m in Sources */,
 				34BECE2E1F7ABCE000D7438D /* GifPickerViewController.swift in Sources */,
+				B84664F3234FE4540083A1CD /* Mention.swift in Sources */,
 				34D1F0C01F8EC1760066283D /* MessageRecipientStatusUtils.swift in Sources */,
 				45F659731E1BD99C00444429 /* CallKitCallUIAdaptee.swift in Sources */,
 				34277A5E20751BDC006049F2 /* OWSQuotedMessageView.m in Sources */,

Signal/src/Loki/Mention.swift

@@ -0,0 +1,13 @@
+
+@objc(LKMention)
+public final class Mention : NSObject {
+    @objc public let locationInString: UInt
+    @objc public let hexEncodedPublicKey: String
+    @objc public let displayName: String
+    
+    @objc public init(locationInString: UInt, hexEncodedPublicKey: String, displayName: String) {
+        self.locationInString = locationInString
+        self.hexEncodedPublicKey = hexEncodedPublicKey
+        self.displayName = displayName
+    }
+}

Signal/src/Loki/UserSelectionView.swift

@@ -3,7 +3,7 @@
 
 @objc(LKUserSelectionView)
 final class UserSelectionView : UIView, UITableViewDataSource, UITableViewDelegate {
-    @objc var users: [String] = [] { didSet { tableView.reloadData(); tableView.contentOffset = CGPoint.zero } }
+    @objc var users: [String] = [] { didSet { tableView.reloadData() } }
     @objc var hasGroupContext = false
     @objc var delegate: UserSelectionViewDelegate?
     

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -213,7 +213,10 @@ typedef enum : NSUInteger {
 @property (nonatomic) CGFloat extraContentInsetPadding;
 @property (nonatomic) CGFloat contentInsetBottom;
 
-@property (nonatomic) NSInteger mentionStartIndex;
+// Mentions
+@property (nonatomic) NSInteger currentMentionStartIndex;
+@property (nonatomic) NSMutableArray<LKMention *> *mentions;
+@property (nonatomic) NSString *oldText;
 
 @end
 
@@ -259,7 +262,8 @@ typedef enum : NSUInteger {
 
     self.scrollContinuity = kScrollContinuityBottom;
     
-    _mentionStartIndex = -1;
+    _currentMentionStartIndex = -1;
+    _mentions = [NSMutableArray new];
 }
 
 #pragma mark - Dependencies
@@ -3018,6 +3022,9 @@ typedef enum : NSUInteger {
 {
     [self tryToSendAttachments:attachments messageText:messageText];
     [self.inputToolbar clearTextMessageAnimated:NO];
+    self.oldText = @"";
+    self.currentMentionStartIndex = -1;
+    self.mentions = @[].mutableCopy;
 
     // we want to already be at the bottom when the user returns, rather than have to watch
     // the new message scroll into view.
@@ -3769,32 +3776,74 @@ typedef enum : NSUInteger {
 
 - (void)textViewDidChange:(UITextView *)textView
 {
-    if (textView.text.length == 0) { return; }
+    // Prepare
+    NSString *newText = textView.text;
+    // Typing indicators
+    if (newText.length > 0) {
         [self.typingIndicators didStartTypingOutgoingInputInThread:self.thread];
-    NSUInteger currentEndIndex = textView.text.length - 1;
+    }
-    unichar lastCharacter = [textView.text characterAtIndex:currentEndIndex];
+    // Mentions
+    BOOL isBackspace = newText.length < self.oldText.length;
+    if (isBackspace) {
+        self.currentMentionStartIndex = -1;
+        for (LKMention *mention in self.mentions) {
+            BOOL isValid;
+            if (mention.locationInString > (NSUInteger)MAX((NSInteger)newText.length - 1, 0)) {
+                isValid = NO;
+            } else {
+                isValid = [[newText substringFromIndex:mention.locationInString] hasPrefix:[NSString stringWithFormat:@"@%@", mention.displayName]];
+            }
+            if (!isValid) {
+                [self.mentions removeObject:mention];
+            }
+        }
+    } else if (newText.length > 0) {
+        NSUInteger currentEndIndex = newText.length - 1;
+        unichar lastCharacter = [newText characterAtIndex:currentEndIndex];
         if (lastCharacter == '@') {
             NSArray<NSString *> *userIDs = [LKAPI getUserIDsFor:@"" in:self.thread.uniqueId];
-        self.mentionStartIndex = (NSInteger)currentEndIndex + 1;
+            self.currentMentionStartIndex = (NSInteger)currentEndIndex;
             [self.inputToolbar showUserSelectionViewFor:userIDs in:self.thread];
         } else if ([NSCharacterSet.whitespaceAndNewlineCharacterSet characterIsMember:lastCharacter]) {
-        self.mentionStartIndex = -1;
+            self.currentMentionStartIndex = -1;
             [self.inputToolbar hideUserSelectionView];
         } else {
-        if (self.mentionStartIndex != -1) {
+            if (self.currentMentionStartIndex != -1) {
-            NSString *query = [textView.text substringFromIndex:(NSUInteger)self.mentionStartIndex];
+                NSString *query = [newText substringFromIndex:(NSUInteger)self.currentMentionStartIndex + 1]; // + 1 to get rid of the @
                 NSArray<NSString *> *userIDs = [LKAPI getUserIDsFor:query in:self.thread.uniqueId];
                 [self.inputToolbar showUserSelectionViewFor:userIDs in:self.thread];
             }
         }
+    }
+    self.oldText = newText;
 }
 
-- (void)handleUserSelected:(NSString *)user from:(LKUserSelectionView *)userSelectionView
+- (void)handleUserSelected:(NSString *)hexEncodedPublicKey from:(LKUserSelectionView *)userSelectionView
 {
+    NSUInteger mentionStartIndex = (NSUInteger)self.currentMentionStartIndex;
+    __block NSString *displayName;
+    [OWSPrimaryStorage.sharedManager.dbReadConnection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
+        NSString *collection = [NSString stringWithFormat:@"%@.%llu", LKGroupChatAPI.publicChatServer, LKGroupChatAPI.publicChatServerID];
+        displayName = [transaction objectForKey:hexEncodedPublicKey inCollection:collection];
+    }];
+    LKMention *mention = [[LKMention alloc] initWithLocationInString:mentionStartIndex hexEncodedPublicKey:hexEncodedPublicKey displayName:displayName];
+    [self.mentions addObject:mention];
     NSString *oldText = self.inputToolbar.messageText;
-    NSUInteger mentionStartIndex = (NSUInteger)self.mentionStartIndex;
+    NSString *newText = [oldText stringByReplacingCharactersInRange:NSMakeRange(mentionStartIndex, oldText.length - mentionStartIndex) withString:[NSString stringWithFormat:@"@%@", displayName]];
-    NSString *newText = [oldText stringByReplacingCharactersInRange:NSMakeRange(mentionStartIndex, oldText.length - mentionStartIndex) withString:user];
     [self.inputToolbar setMessageText:newText animated:NO];
+    [self.inputToolbar hideUserSelectionView];
+}
+
+- (NSString *)getMessageBody
+{
+    NSString *result = self.inputToolbar.messageText;
+    NSUInteger shift = 0;
+    for (LKMention *mention in self.mentions) {
+        NSRange range = NSMakeRange(mention.locationInString + shift, mention.displayName.length + 1); // + 1 to include the @
+        shift = shift + mention.hexEncodedPublicKey.length - mention.displayName.length;
+        result = [result stringByReplacingCharactersInRange:range withString:[[NSString alloc] initWithFormat:@"@%@", mention.hexEncodedPublicKey]];
+    }
+    return result;
 }
 
 - (void)inputTextViewSendMessagePressed
@@ -4045,6 +4094,9 @@ typedef enum : NSUInteger {
 {
     [self tryToSendAttachments:attachments messageText:messageText];
     [self.inputToolbar clearTextMessageAnimated:NO];
+    self.oldText = @"";
+    self.currentMentionStartIndex = -1;
+    self.mentions = @[].mutableCopy;
     [self dismissViewControllerAnimated:YES completion:nil];
 
     // We always want to scroll to the bottom of the conversation after the local user
@@ -4415,7 +4467,7 @@ typedef enum : NSUInteger {
     [BenchManager startEventWithTitle:@"Send Message milestone: toggleDefaultKeyboard completed"
                               eventId:@"fromSendUntil_toggleDefaultKeyboard"];
 
-    [self tryToSendTextMessage:self.inputToolbar.messageText updateKeyboardState:YES];
+    [self tryToSendTextMessage:[self getMessageBody] updateKeyboardState:YES];
 }
 
 - (void)tryToSendTextMessage:(NSString *)text updateKeyboardState:(BOOL)updateKeyboardState
@@ -4473,6 +4525,9 @@ typedef enum : NSUInteger {
     [BenchManager benchWithTitle:@"clearTextMessageAnimated"
                            block:^{
                                [self.inputToolbar clearTextMessageAnimated:YES];
+                               self.oldText = @"";
+                               self.currentMentionStartIndex = -1;
+                               self.mentions = @[].mutableCopy;
                            }];
     [BenchManager completeEventWithEventId:@"fromSendUntil_clearTextMessageAnimated"];