Merge branch 'mkirk/sharp-corners'

Signal/src/ViewControllers/ConversationView/Cells/OWSBubbleView.h

@@ -9,6 +9,14 @@ NS_ASSUME_NONNULL_BEGIN
 extern const CGFloat kOWSMessageCellCornerRadius_Large;
 extern const CGFloat kOWSMessageCellCornerRadius_Small;
 
+typedef NS_OPTIONS(NSUInteger, OWSDirectionalRectCorner) {
+    OWSDirectionalRectCornerTopLeading = 1 << 0,
+    OWSDirectionalRectCornerTopTrailing = 1 << 1,
+    OWSDirectionalRectCornerBottomLeading = 1 << 2,
+    OWSDirectionalRectCornerBottomTrailing = 1 << 3,
+    OWSDirectionalRectCornerAllCorners = ~0UL
+};
+
 @class OWSBubbleView;
 
 @protocol OWSBubbleViewPartner <NSObject>
@@ -23,10 +31,17 @@ extern const CGFloat kOWSMessageCellCornerRadius_Small;
 
 @interface OWSBubbleView : UIView
 
++ (UIBezierPath *)roundedBezierRectWithBubbleTop:(CGFloat)bubbleTop
+                                      bubbleLeft:(CGFloat)bubbleLeft
+                                    bubbleBottom:(CGFloat)bubbleBottom
+                                     bubbleRight:(CGFloat)bubbleRight
+                               sharpCornerRadius:(CGFloat)sharpCornerRadius
+                                wideCornerRadius:(CGFloat)wideCornerRadius
+                                    sharpCorners:(OWSDirectionalRectCorner)sharpCorners;
+
 @property (nonatomic, nullable) UIColor *bubbleColor;
 
-@property (nonatomic) BOOL useSmallCorners_Top;
-@property (nonatomic) BOOL useSmallCorners_Bottom;
+@property (nonatomic) OWSDirectionalRectCorner sharpCorners;
 
 - (UIBezierPath *)maskPath;
 

Signal/src/ViewControllers/ConversationView/Cells/OWSBubbleView.m

@@ -3,12 +3,42 @@
 //
 
 #import "OWSBubbleView.h"
+#import "MainAppContext.h"
 #import <SignalMessaging/UIView+OWS.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
+UIRectCorner UIRectCornerForOWSDirectionalRectCorner(OWSDirectionalRectCorner corner);
+UIRectCorner UIRectCornerForOWSDirectionalRectCorner(OWSDirectionalRectCorner corner)
+{
+    if (corner == OWSDirectionalRectCornerAllCorners) {
+        return UIRectCornerAllCorners;
+    }
+
+    UIRectCorner rectCorner = 0;
+    BOOL isRTL = CurrentAppContext().isRTL;
+
+    if (corner & OWSDirectionalRectCornerTopLeading) {
+        rectCorner = rectCorner | (isRTL ? UIRectCornerTopRight : UIRectCornerTopLeft);
+    }
+
+    if (corner & OWSDirectionalRectCornerTopTrailing) {
+        rectCorner = rectCorner | (isRTL ? UIRectCornerTopLeft : UIRectCornerTopRight);
+    }
+
+    if (corner & OWSDirectionalRectCornerBottomTrailing) {
+        rectCorner = rectCorner | (isRTL ? UIRectCornerBottomLeft : UIRectCornerBottomRight);
+    }
+
+    if (corner & OWSDirectionalRectCornerBottomLeading) {
+        rectCorner = rectCorner | (isRTL ? UIRectCornerBottomRight : UIRectCornerBottomLeft);
+    }
+
+    return rectCorner;
+}
+
 const CGFloat kOWSMessageCellCornerRadius_Large = 18;
-const CGFloat kOWSMessageCellCornerRadius_Small = 2;
+const CGFloat kOWSMessageCellCornerRadius_Small = 4;
 
 @interface OWSBubbleView ()
 
@@ -101,16 +131,9 @@ const CGFloat kOWSMessageCellCornerRadius_Small = 2;
     [CATransaction commit];
 }
 
-- (void)setUseSmallCorners_Top:(BOOL)useSmallCorners_Top
+- (void)setSharpCorners:(OWSDirectionalRectCorner)sharpCorners
 {
-    _useSmallCorners_Top = useSmallCorners_Top;
-
-    [self updateLayers];
-}
-
-- (void)setUseSmallCorners_Bottom:(BOOL)useSmallCorners_Bottom
-{
-    _useSmallCorners_Bottom = useSmallCorners_Bottom;
+    _sharpCorners = sharpCorners;
 
     [self updateLayers];
 }
@@ -139,63 +162,82 @@ const CGFloat kOWSMessageCellCornerRadius_Small = 2;
 
 - (UIBezierPath *)maskPath
 {
-    return [self.class maskPathForSize:self.bounds.size
-                   useSmallCorners_Top:self.useSmallCorners_Top
-                useSmallCorners_Bottom:self.useSmallCorners_Bottom];
+    return [self.class maskPathForSize:self.bounds.size sharpCorners:self.sharpCorners];
 }
 
-+ (UIBezierPath *)maskPathForSize:(CGSize)size
-              useSmallCorners_Top:(BOOL)useSmallCorners_Top
-           useSmallCorners_Bottom:(BOOL)useSmallCorners_Bottom
++ (UIBezierPath *)maskPathForSize:(CGSize)size sharpCorners:(OWSDirectionalRectCorner)sharpCorners
 {
     CGRect bounds = CGRectZero;
     bounds.size = size;
 
-    UIBezierPath *bezierPath = [UIBezierPath new];
-
-    CGFloat bubbleLeft = 0.f;
-    CGFloat bubbleRight = size.width;
     CGFloat bubbleTop = 0.f;
+    CGFloat bubbleLeft = 0.f;
     CGFloat bubbleBottom = size.height;
-    CGFloat topRounding = (useSmallCorners_Top ? kOWSMessageCellCornerRadius_Small : kOWSMessageCellCornerRadius_Large);
-    CGFloat bottomRounding
-        = (useSmallCorners_Bottom ? kOWSMessageCellCornerRadius_Small : kOWSMessageCellCornerRadius_Large);
+    CGFloat bubbleRight = size.width;
+
+    return [OWSBubbleView roundedBezierRectWithBubbleTop:bubbleTop
+                                              bubbleLeft:bubbleLeft
+                                            bubbleBottom:bubbleBottom
+                                             bubbleRight:bubbleRight
+                                       sharpCornerRadius:kOWSMessageCellCornerRadius_Small
+                                        wideCornerRadius:kOWSMessageCellCornerRadius_Large
+                                            sharpCorners:sharpCorners];
+}
+
++ (UIBezierPath *)roundedBezierRectWithBubbleTop:(CGFloat)bubbleTop
+                                      bubbleLeft:(CGFloat)bubbleLeft
+                                    bubbleBottom:(CGFloat)bubbleBottom
+                                     bubbleRight:(CGFloat)bubbleRight
+                               sharpCornerRadius:(CGFloat)sharpCornerRadius
+                                wideCornerRadius:(CGFloat)wideCornerRadius
+                                    sharpCorners:(OWSDirectionalRectCorner)sharpCorners
+{
+    UIBezierPath *bezierPath = [UIBezierPath new];
+
+    UIRectCorner uiSharpCorners = UIRectCornerForOWSDirectionalRectCorner(sharpCorners);
+
+    const CGFloat topLeftRounding = (uiSharpCorners & UIRectCornerTopLeft) ? sharpCornerRadius : wideCornerRadius;
+    const CGFloat topRightRounding = (uiSharpCorners & UIRectCornerTopRight) ? sharpCornerRadius : wideCornerRadius;
+
+    const CGFloat bottomRightRounding
+        = (uiSharpCorners & UIRectCornerBottomRight) ? sharpCornerRadius : wideCornerRadius;
+    const CGFloat bottomLeftRounding = (uiSharpCorners & UIRectCornerBottomLeft) ? sharpCornerRadius : wideCornerRadius;
 
     const CGFloat topAngle = 3.0f * M_PI_2;
     const CGFloat rightAngle = 0.0f;
     const CGFloat bottomAngle = M_PI_2;
     const CGFloat leftAngle = M_PI;
 
-    [bezierPath moveToPoint:CGPointMake(bubbleLeft + topRounding, bubbleTop)];
+    // starting just to the right of the top left corner and working clockwise
+    [bezierPath moveToPoint:CGPointMake(bubbleLeft + topLeftRounding, bubbleTop)];
 
     // top right corner
-    [bezierPath addArcWithCenter:CGPointMake(bubbleRight - topRounding, bubbleTop + topRounding)
-                          radius:topRounding
+    [bezierPath addArcWithCenter:CGPointMake(bubbleRight - topRightRounding, bubbleTop + topRightRounding)
+                          radius:topRightRounding
                       startAngle:topAngle
                         endAngle:rightAngle
                        clockwise:true];
 
     // bottom right corner
-    [bezierPath addArcWithCenter:CGPointMake(bubbleRight - bottomRounding, bubbleBottom - bottomRounding)
-                          radius:bottomRounding
+    [bezierPath addArcWithCenter:CGPointMake(bubbleRight - bottomRightRounding, bubbleBottom - bottomRightRounding)
+                          radius:bottomRightRounding
                       startAngle:rightAngle
                         endAngle:bottomAngle
                        clockwise:true];
 
     // bottom left corner
-    [bezierPath addArcWithCenter:CGPointMake(bubbleLeft + bottomRounding, bubbleBottom - bottomRounding)
-                          radius:bottomRounding
+    [bezierPath addArcWithCenter:CGPointMake(bubbleLeft + bottomLeftRounding, bubbleBottom - bottomLeftRounding)
+                          radius:bottomLeftRounding
                       startAngle:bottomAngle
                         endAngle:leftAngle
                        clockwise:true];
 
     // top left corner
-    [bezierPath addArcWithCenter:CGPointMake(bubbleLeft + topRounding, bubbleTop + topRounding)
-                          radius:topRounding
+    [bezierPath addArcWithCenter:CGPointMake(bubbleLeft + topLeftRounding, bubbleTop + topLeftRounding)
+                          radius:topLeftRounding
                       startAngle:leftAngle
                         endAngle:topAngle
                        clockwise:true];
-
     return bezierPath;
 }
 
@@ -228,11 +270,7 @@ const CGFloat kOWSMessageCellCornerRadius_Small = 2;
 
 - (CGFloat)minWidth
 {
-    if (self.useSmallCorners_Top && self.useSmallCorners_Bottom) {
-        return (kOWSMessageCellCornerRadius_Small * 2);
-    } else {
-        return (kOWSMessageCellCornerRadius_Large * 2);
-    }
+    return (kOWSMessageCellCornerRadius_Large * 2);
 }
 
 @end

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageBubbleView.m

@@ -268,7 +268,6 @@ NS_ASSUME_NONNULL_BEGIN
             [self.stackView addArrangedSubview:spacerView];
         }
 
-        BOOL isOutgoing = [self.viewItem.interaction isKindOfClass:TSOutgoingMessage.class];
         DisplayableText *_Nullable displayableQuotedText
             = (self.viewItem.hasQuotedText ? self.viewItem.displayableQuotedText : nil);
 
@@ -276,8 +275,8 @@ NS_ASSUME_NONNULL_BEGIN
             [OWSQuotedMessageView quotedMessageViewForConversation:self.viewItem.quotedReply
                                              displayableQuotedText:displayableQuotedText
                                                  conversationStyle:self.conversationStyle
-                                                        isOutgoing:isOutgoing
-                                  sharesTopBorderWithMessageBubble:!self.shouldShowSenderName];
+                                                        isOutgoing:self.isOutgoing
+                                                      sharpCorners:self.sharpCornersForQuotedMessage];
         quotedMessageView.delegate = self;
 
         self.quotedMessageView = quotedMessageView;
@@ -559,12 +558,35 @@ NS_ASSUME_NONNULL_BEGIN
     return 12.f;
 }
 
+- (OWSDirectionalRectCorner)sharpCorners
+{
+    OWSDirectionalRectCorner sharpCorners = 0;
+
+    if (!self.viewItem.isFirstInCluster) {
+        sharpCorners = sharpCorners
+            | (self.isIncoming ? OWSDirectionalRectCornerTopLeading : OWSDirectionalRectCornerTopTrailing);
+    }
+
+    if (!self.viewItem.isLastInCluster) {
+        sharpCorners = sharpCorners
+            | (self.isIncoming ? OWSDirectionalRectCornerBottomLeading : OWSDirectionalRectCornerBottomTrailing);
+    }
+
+    return sharpCorners;
+}
+
+- (OWSDirectionalRectCorner)sharpCornersForQuotedMessage
+{
+    if (self.viewItem.senderName) {
+        return OWSDirectionalRectCornerAllCorners;
+    } else {
+        return self.sharpCorners | OWSDirectionalRectCornerBottomLeading | OWSDirectionalRectCornerBottomTrailing;
+    }
+}
+
 - (void)configureBubbleRounding
 {
-    self.bubbleView.useSmallCorners_Top
-        = (self.hasBodyMediaWithThumbnail && !self.shouldShowSenderName && !self.isQuotedReply);
-    self.bubbleView.useSmallCorners_Bottom
-        = (self.hasBodyMediaWithThumbnail && !self.hasBodyText && !self.hasBottomFooter);
+    self.bubbleView.sharpCorners = self.sharpCorners;
 }
 
 - (void)updateBubbleColor
@@ -1199,7 +1221,6 @@ NS_ASSUME_NONNULL_BEGIN
         return nil;
     }
 
-    BOOL isOutgoing = [self.viewItem.interaction isKindOfClass:TSOutgoingMessage.class];
     DisplayableText *_Nullable displayableQuotedText
         = (self.viewItem.hasQuotedText ? self.viewItem.displayableQuotedText : nil);
 
@@ -1207,8 +1228,8 @@ NS_ASSUME_NONNULL_BEGIN
         [OWSQuotedMessageView quotedMessageViewForConversation:self.viewItem.quotedReply
                                          displayableQuotedText:displayableQuotedText
                                              conversationStyle:self.conversationStyle
-                                                    isOutgoing:isOutgoing
-                              sharesTopBorderWithMessageBubble:NO];
+                                                    isOutgoing:self.isOutgoing
+                                                  sharpCorners:self.sharpCornersForQuotedMessage];
     CGSize result = [quotedMessageView sizeForMaxWidth:self.conversationStyle.maxMessageWidth];
     return [NSValue valueWithCGSize:CGSizeCeil(result)];
 }

Signal/src/ViewControllers/ConversationView/Cells/OWSQuotedMessageView.h

@@ -2,6 +2,8 @@
 //  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
+#import "OWSBubbleView.h"
+
 NS_ASSUME_NONNULL_BEGIN
 
 @class ConversationStyle;
@@ -35,7 +37,7 @@ NS_ASSUME_NONNULL_BEGIN
                                      displayableQuotedText:(nullable DisplayableText *)displayableQuotedText
                                          conversationStyle:(ConversationStyle *)conversationStyle
                                                 isOutgoing:(BOOL)isOutgoing
-                          sharesTopBorderWithMessageBubble:(BOOL)sharesTopBorderWithMessageBubble;
+                                              sharpCorners:(OWSDirectionalRectCorner)sharpCorners;
 
 // Factory method for "message compose" views.
 + (OWSQuotedMessageView *)quotedMessageViewForPreview:(OWSQuotedReplyModel *)quotedMessage

Signal/src/ViewControllers/ConversationView/Cells/OWSQuotedMessageView.m

@@ -5,7 +5,7 @@
 #import "OWSQuotedMessageView.h"
 #import "ConversationViewItem.h"
 #import "Environment.h"
-#import "OWSBubbleShapeView.h"
+#import "OWSBubbleView.h"
 #import "Signal-Swift.h"
 #import <SignalMessaging/OWSContactsManager.h>
 #import <SignalMessaging/SignalMessaging-Swift.h>
@@ -25,7 +25,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 @property (nonatomic, readonly) BOOL isForPreview;
 @property (nonatomic, readonly) BOOL isOutgoing;
-@property (nonatomic, readonly) BOOL sharesTopBorderWithMessageBubble;
+@property (nonatomic, readonly) OWSDirectionalRectCorner sharpCorners;
 
 @property (nonatomic, readonly) UILabel *quotedAuthorLabel;
 @property (nonatomic, readonly) UILabel *quotedTextLabel;
@@ -40,7 +40,7 @@ NS_ASSUME_NONNULL_BEGIN
                                      displayableQuotedText:(nullable DisplayableText *)displayableQuotedText
                                          conversationStyle:(ConversationStyle *)conversationStyle
                                                 isOutgoing:(BOOL)isOutgoing
-                          sharesTopBorderWithMessageBubble:(BOOL)sharesTopBorderWithMessageBubble
+                                              sharpCorners:(OWSDirectionalRectCorner)sharpCorners
 {
     OWSAssert(quotedMessage);
 
@@ -49,7 +49,7 @@ NS_ASSUME_NONNULL_BEGIN
                                              conversationStyle:conversationStyle
                                                   isForPreview:NO
                                                     isOutgoing:isOutgoing
-                              sharesTopBorderWithMessageBubble:sharesTopBorderWithMessageBubble];
+                                                  sharpCorners:sharpCorners];
 }
 
 + (OWSQuotedMessageView *)quotedMessageViewForPreview:(OWSQuotedReplyModel *)quotedMessage
@@ -62,12 +62,13 @@ NS_ASSUME_NONNULL_BEGIN
         displayableQuotedText = [DisplayableText displayableText:quotedMessage.body];
     }
 
-    OWSQuotedMessageView *instance = [[OWSQuotedMessageView alloc] initWithQuotedMessage:quotedMessage
-                                                                   displayableQuotedText:displayableQuotedText
-                                                                       conversationStyle:conversationStyle
-                                                                            isForPreview:YES
-                                                                              isOutgoing:YES
-                                                        sharesTopBorderWithMessageBubble:NO];
+    OWSQuotedMessageView *instance =
+        [[OWSQuotedMessageView alloc] initWithQuotedMessage:quotedMessage
+                                      displayableQuotedText:displayableQuotedText
+                                          conversationStyle:conversationStyle
+                                               isForPreview:YES
+                                                 isOutgoing:YES
+                                               sharpCorners:OWSDirectionalRectCornerAllCorners];
     [instance createContents];
     return instance;
 }
@@ -77,7 +78,7 @@ NS_ASSUME_NONNULL_BEGIN
                     conversationStyle:(ConversationStyle *)conversationStyle
                          isForPreview:(BOOL)isForPreview
                            isOutgoing:(BOOL)isOutgoing
-     sharesTopBorderWithMessageBubble:(BOOL)sharesTopBorderWithMessageBubble
+                         sharpCorners:(OWSDirectionalRectCorner)sharpCorners
 {
     self = [super init];
 
@@ -92,7 +93,7 @@ NS_ASSUME_NONNULL_BEGIN
     _isForPreview = isForPreview;
     _conversationStyle = conversationStyle;
     _isOutgoing = isOutgoing;
-    _sharesTopBorderWithMessageBubble = sharesTopBorderWithMessageBubble;
+    _sharpCorners = sharpCorners;
 
     _quotedAuthorLabel = [UILabel new];
     _quotedTextLabel = [UILabel new];
@@ -151,34 +152,28 @@ NS_ASSUME_NONNULL_BEGIN
     self.clipsToBounds = YES;
 
     CAShapeLayer *maskLayer = [CAShapeLayer new];
-    BOOL sharesTopBorderWithMessageBubble = self.sharesTopBorderWithMessageBubble;
+    OWSDirectionalRectCorner sharpCorners = self.sharpCorners;
+
     OWSLayerView *innerBubbleView = [[OWSLayerView alloc]
          initWithFrame:CGRectZero
         layoutCallback:^(UIView *layerView) {
             CGRect layerFrame = layerView.bounds;
 
-            UIBezierPath *bezierPath = [UIBezierPath new];
-
-            CGFloat bubbleLeft = 0.f;
-            CGFloat bubbleRight = layerFrame.size.width;
-            CGFloat bubbleTop = 0.f;
-            CGFloat bubbleBottom = layerFrame.size.height;
-            CGFloat bubbleTopRounding = (sharesTopBorderWithMessageBubble ? 10.f : 4.f);
-            CGFloat bubbleBottomRounding = 4.f;
-
-            [bezierPath moveToPoint:CGPointMake(bubbleLeft + bubbleTopRounding, bubbleTop)];
-            [bezierPath addLineToPoint:CGPointMake(bubbleRight - bubbleTopRounding, bubbleTop)];
-            [bezierPath addQuadCurveToPoint:CGPointMake(bubbleRight, bubbleTop + bubbleTopRounding)
-                               controlPoint:CGPointMake(bubbleRight, bubbleTop)];
-            [bezierPath addLineToPoint:CGPointMake(bubbleRight, bubbleBottom - bubbleBottomRounding)];
-            [bezierPath addQuadCurveToPoint:CGPointMake(bubbleRight - bubbleBottomRounding, bubbleBottom)
-                               controlPoint:CGPointMake(bubbleRight, bubbleBottom)];
-            [bezierPath addLineToPoint:CGPointMake(bubbleLeft + bubbleBottomRounding, bubbleBottom)];
-            [bezierPath addQuadCurveToPoint:CGPointMake(bubbleLeft, bubbleBottom - bubbleBottomRounding)
-                               controlPoint:CGPointMake(bubbleLeft, bubbleBottom)];
-            [bezierPath addLineToPoint:CGPointMake(bubbleLeft, bubbleTop + bubbleTopRounding)];
-            [bezierPath addQuadCurveToPoint:CGPointMake(bubbleLeft + bubbleTopRounding, bubbleTop)
-                               controlPoint:CGPointMake(bubbleLeft, bubbleTop)];
+            const CGFloat bubbleLeft = 0.f;
+            const CGFloat bubbleRight = layerFrame.size.width;
+            const CGFloat bubbleTop = 0.f;
+            const CGFloat bubbleBottom = layerFrame.size.height;
+
+            const CGFloat sharpCornerRadius = 4;
+            const CGFloat wideCornerRadius = 10;
+
+            UIBezierPath *bezierPath = [OWSBubbleView roundedBezierRectWithBubbleTop:bubbleTop
+                                                                          bubbleLeft:bubbleLeft
+                                                                        bubbleBottom:bubbleBottom
+                                                                         bubbleRight:bubbleRight
+                                                                   sharpCornerRadius:sharpCornerRadius
+                                                                    wideCornerRadius:wideCornerRadius
+                                                                        sharpCorners:sharpCorners];
 
             maskLayer.path = bezierPath.CGPath;
         }];

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -4865,6 +4865,8 @@ typedef enum : NSUInteger {
         ConversationViewItem *_Nullable nextViewItem = (i + 1 < viewItems.count ? viewItems[i + 1] : nil);
         BOOL shouldShowSenderAvatar = NO;
         BOOL shouldHideFooter = NO;
+        BOOL isFirstInCluster = YES;
+        BOOL isLastInCluster = YES;
         NSAttributedString *_Nullable senderName = nil;
 
         OWSInteractionType interactionType = viewItem.interaction.interactionType;
@@ -4888,6 +4890,21 @@ typedef enum : NSUInteger {
                     && receiptStatus == nextReceiptStatus
                     && outgoingMessage.messageState != TSOutgoingMessageStateFailed && !nextViewItem.shouldShowDate);
             }
+
+            // clustering
+            if (previousViewItem == nil) {
+                isFirstInCluster = YES;
+            } else {
+                isFirstInCluster = previousViewItem.interaction.interactionType != OWSInteractionType_OutgoingMessage;
+            }
+
+            if (nextViewItem == nil) {
+                isLastInCluster = YES;
+            } else if (nextViewItem.shouldShowDate) {
+                isLastInCluster = YES;
+            } else {
+                isLastInCluster = nextViewItem.interaction.interactionType != OWSInteractionType_OutgoingMessage;
+            }
         } else if (interactionType == OWSInteractionType_IncomingMessage) {
 
             TSIncomingMessage *incomingMessage = (TSIncomingMessage *)viewItem.interaction;
@@ -4909,6 +4926,27 @@ typedef enum : NSUInteger {
                     [NSObject isNullableObject:nextIncomingSenderId equalTo:incomingSenderId];
             }
 
+            // clustering
+            if (previousViewItem == nil) {
+                isFirstInCluster = YES;
+            } else if (previousViewItem.interaction.interactionType != OWSInteractionType_IncomingMessage) {
+                isFirstInCluster = YES;
+            } else {
+                TSIncomingMessage *previousIncomingMessage = (TSIncomingMessage *)previousViewItem.interaction;
+                isFirstInCluster = ![incomingSenderId isEqual:previousIncomingMessage.authorId];
+            }
+
+            if (nextViewItem == nil) {
+                isLastInCluster = YES;
+            } else if (nextViewItem.interaction.interactionType != OWSInteractionType_IncomingMessage) {
+                isLastInCluster = YES;
+            } else if (nextViewItem.shouldShowDate) {
+                isLastInCluster = YES;
+            } else {
+                TSIncomingMessage *nextIncomingMessage = (TSIncomingMessage *)nextViewItem.interaction;
+                isLastInCluster = ![incomingSenderId isEqual:nextIncomingMessage.authorId];
+            }
+
             if (viewItem.isGroupThread) {
                 // Show the sender name for incoming group messages unless
                 // the previous message has the same sender name and
@@ -4944,6 +4982,8 @@ typedef enum : NSUInteger {
             }
         }
 
+        viewItem.isFirstInCluster = isFirstInCluster;
+        viewItem.isLastInCluster = isLastInCluster;
         viewItem.shouldShowSenderAvatar = shouldShowSenderAvatar;
         viewItem.shouldHideFooter = shouldHideFooter;
         viewItem.senderName = senderName;

Signal/src/ViewControllers/ConversationView/ConversationViewItem.h

@@ -58,6 +58,8 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType);
 @property (nonatomic) BOOL shouldShowSenderAvatar;
 @property (nonatomic, nullable) NSAttributedString *senderName;
 @property (nonatomic) BOOL shouldHideFooter;
+@property (nonatomic) BOOL isFirstInCluster;
+@property (nonatomic) BOOL isLastInCluster;
 
 @property (nonatomic, readonly) ConversationStyle *conversationStyle;