chore(ui): minor changes and assertion.

Signed-off-by: xsahil03x <[email protected]>

packages/stream_chat_flutter/lib/src/message_widget/message_widget.dart

@@ -618,6 +618,11 @@ class StreamMessageWidget extends StatefulWidget {
     String? imageAttachmentThumbnailResizeType,
     String? imageAttachmentThumbnailCropType,
   }) {
+    assert(
+      bottomRowBuilder == null || bottomRowBuilderWithDefaultWidget == null,
+      'You can only use one of the two bottom row builders',
+    );
+
     var _bottomRowBuilderWithDefaultWidget =
         bottomRowBuilderWithDefaultWidget ??
             this.bottomRowBuilderWithDefaultWidget;
@@ -629,9 +634,10 @@ class StreamMessageWidget extends StatefulWidget {
       }
 
       return defaultWidget.copyWith(
-        onThreadTap: onThreadTap,
-        usernameBuilder: usernameBuilder,
-        deletedBottomRowBuilder: deletedBottomRowBuilder,
+        onThreadTap: onThreadTap ?? this.onThreadTap,
+        usernameBuilder: usernameBuilder ?? this.usernameBuilder,
+        deletedBottomRowBuilder:
+            deletedBottomRowBuilder ?? this.deletedBottomRowBuilder,
       );
     };
 
@@ -883,7 +889,25 @@ class _StreamMessageWidgetState extends State<StreamMessageWidget>
                       ? Alignment.centerRight
                       : Alignment.centerLeft,
                   widthFactor: widget.widthFactor,
-                  child: MessageWidgetContent(
+                  child: Builder(builder: (context) {
+                    var _bottomRowBuilderWithDefaultWidget =
+                        widget.bottomRowBuilderWithDefaultWidget;
+
+                    _bottomRowBuilderWithDefaultWidget ??=
+                        (context, message, defaultWidget) {
+                      final _bottomRowBuilder = widget.bottomRowBuilder;
+                      if (_bottomRowBuilder != null) {
+                        return _bottomRowBuilder(context, message);
+                      }
+
+                      return defaultWidget.copyWith(
+                        onThreadTap: widget.onThreadTap,
+                        usernameBuilder: widget.usernameBuilder,
+                        deletedBottomRowBuilder: widget.deletedBottomRowBuilder,
+                      );
+                    };
+
+                    return MessageWidgetContent(
                       streamChatTheme: _streamChatTheme,
                       showUsername: showUsername,
                       showTimeStamp: showTimeStamp,
@@ -923,10 +947,11 @@ class _StreamMessageWidgetState extends State<StreamMessageWidget>
                       onMentionTap: widget.onMentionTap,
                       onQuotedMessageTap: widget.onQuotedMessageTap,
                       bottomRowBuilderWithDefaultWidget:
-                        widget.bottomRowBuilderWithDefaultWidget,
+                          _bottomRowBuilderWithDefaultWidget,
                       onUserAvatarTap: widget.onUserAvatarTap,
                       userAvatarBuilder: widget.userAvatarBuilder,
-                  ),
+                    );
+                  }),
                 ),
               ),
             ),