Refine message composer layout

lib/screens/messages_tab.dart

@@ -49,6 +49,7 @@ class MessagesTab extends StatefulWidget {
 class _MessagesTabState extends State<MessagesTab> {
   static const int _maxContactMessageBytes = 156;
   static const int _maxChannelMessageBytes = 127;
+  static const double _composerOverlayHeight = 148;
 
   final TextEditingController _textController = TextEditingController();
   final FocusNode _focusNode = FocusNode();
@@ -1546,19 +1547,25 @@ class _MessagesTabState extends State<MessagesTab> {
         return GestureDetector(
           behavior: HitTestBehavior.translucent,
           onTap: () => FocusScope.of(context).unfocus(),
-          child: Column(
+          child: Stack(
             children: [
-              Expanded(
+              Positioned.fill(
                 child: MessagesContent(
                   messages: messages,
                   scrollController: _scrollController,
                   highlightedMessageId: _highlightedMessageId,
+                  bottomContentPadding:
+                      _composerOverlayHeight + composerBottomPadding,
                   onRefresh: _handleRefresh,
                   onNavigateToMap: widget.onNavigateToMap,
                   onMessageTap: _handleMessageTap,
                 ),
               ),
-              MessagesComposer(
+              Positioned(
+                left: 0,
+                right: 0,
+                bottom: 0,
+                child: MessagesComposer(
                   textController: _textController,
                   focusNode: _focusNode,
                   messageByteLimiter: _messageByteLimiter,
@@ -1576,6 +1583,7 @@ class _MessagesTabState extends State<MessagesTab> {
                   onStopAndSendVoice: _stopAndSendVoice,
                   onSendMessage: _sendMessage,
                 ),
+              ),
             ],
           ),
         );

lib/widgets/messages/messages_composer.dart

@@ -44,7 +44,7 @@ class MessagesComposer extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return Container(
-      decoration: BoxDecoration(color: Theme.of(context).colorScheme.surface),
+      decoration: const BoxDecoration(color: Colors.transparent),
       child: Column(
         mainAxisSize: MainAxisSize.min,
         children: [

lib/widgets/messages/messages_content.dart

@@ -5,9 +5,12 @@ import '../../models/message.dart';
 import '../../widgets/messages/message_bubble.dart';
 
 class MessagesContent extends StatelessWidget {
+  static const double defaultPadding = 8;
+
   final List<Message> messages;
   final ScrollController scrollController;
   final String? highlightedMessageId;
+  final double bottomContentPadding;
   final Future<void> Function() onRefresh;
   final VoidCallback? onNavigateToMap;
   final ValueChanged<Message>? onMessageTap;
@@ -17,6 +20,7 @@ class MessagesContent extends StatelessWidget {
     required this.messages,
     required this.scrollController,
     required this.highlightedMessageId,
+    this.bottomContentPadding = 0,
     required this.onRefresh,
     this.onNavigateToMap,
     this.onMessageTap,
@@ -64,7 +68,12 @@ class MessagesContent extends StatelessWidget {
               controller: scrollController,
               keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
               reverse: true,
-              padding: const EdgeInsets.all(8),
+              padding: EdgeInsets.fromLTRB(
+                defaultPadding,
+                defaultPadding,
+                defaultPadding,
+                defaultPadding + bottomContentPadding,
+              ),
               itemCount: messages.length,
               itemBuilder: (context, index) {
                 final message = messages[index];