feat: enhance voice call functionality and response handling

- Introduced a new boolean flag `_isSpeaking` in VoiceCallService to manage speaking state during voice interactions.
- Improved response handling by extracting incremental content from socket events and updating the accumulated response accordingly.
- Updated the chat page to include a voice call button, allowing users to initiate voice calls directly from the chat interface.
- Enhanced the modern chat input widget to support voice call functionality, providing a seamless user experience for initiating calls.

lib/features/chat/services/voice_call_service.dart

@@ -190,6 +190,7 @@ class VoiceCallService {
   }
 
   String _accumulatedResponse = '';
+  bool _isSpeaking = false;
 
   void _handleSocketEvent(
     Map<String, dynamic> event,
@@ -204,7 +205,7 @@ class VoiceCallService {
       final innerData = outerData['data'];
 
       if (eventType == 'chat:completion' && innerData is Map<String, dynamic>) {
-        // Handle streaming content chunks
+        // Handle full content replacement (used by some models/backends)
         if (innerData.containsKey('content')) {
           final content = innerData['content']?.toString() ?? '';
           if (content.isNotEmpty) {
@@ -213,18 +214,29 @@ class VoiceCallService {
           }
         }
 
-        // Check for completion using choices[0].finish_reason
+        // Handle streaming delta chunks (incremental updates)
         if (innerData.containsKey('choices')) {
           final choices = innerData['choices'] as List?;
           if (choices != null && choices.isNotEmpty) {
             final firstChoice = choices[0] as Map<String, dynamic>?;
+            final delta = firstChoice?['delta'];
             final finishReason = firstChoice?['finish_reason'];
 
+            // Extract incremental content from delta
+            if (delta is Map<String, dynamic>) {
+              final deltaContent = delta['content']?.toString() ?? '';
+              if (deltaContent.isNotEmpty) {
+                _accumulatedResponse += deltaContent;
+                _responseController.add(_accumulatedResponse);
+              }
+            }
+
+            // Check for completion
             if (finishReason == 'stop') {
-              if (_accumulatedResponse.isNotEmpty) {
+              if (_accumulatedResponse.isNotEmpty && !_isSpeaking) {
                 _speakResponse(_accumulatedResponse);
                 _accumulatedResponse = '';
-              } else {
+              } else if (_accumulatedResponse.isEmpty) {
                 // No response, restart listening
                 _startListening();
               }
@@ -236,9 +248,11 @@ class VoiceCallService {
   }
 
   Future<void> _speakResponse(String response) async {
-    if (_isDisposed) return;
+    if (_isDisposed || _isSpeaking) return;
 
     try {
+      _isSpeaking = true;
+
       // Stop listening before speaking
       await _voiceInput.stopListening();
       await _transcriptSubscription?.cancel();
@@ -248,6 +262,7 @@ class VoiceCallService {
       await _tts.speak(response);
       // After speaking completes, _handleTtsComplete will restart listening
     } catch (e) {
+      _isSpeaking = false;
       _updateState(VoiceCallState.error);
       // Restart listening even if TTS fails
       await _startListening();
@@ -261,6 +276,7 @@ class VoiceCallService {
 
   void _handleTtsComplete() {
     if (_isDisposed) return;
+    _isSpeaking = false;
     // After assistant finishes speaking, start listening for user again
     _startListening();
   }

lib/features/chat/views/chat_page.dart

@@ -1445,16 +1445,6 @@ class _ChatPageState extends ConsumerState<ChatPage> {
                   ),
             actions: [
               if (!_isSelectionMode) ...[
-                // Voice call button
-                IconButton(
-                  icon: Icon(
-                    CupertinoIcons.phone,
-                    color: context.conduitTheme.textPrimary,
-                    size: IconSize.appBar,
-                  ),
-                  onPressed: _handleVoiceCall,
-                  tooltip: 'Voice Call',
-                ),
                 Padding(
                   padding: const EdgeInsets.only(right: Spacing.inputPadding),
                   child: IconButton(
@@ -1566,6 +1556,7 @@ class _ChatPageState extends ConsumerState<ChatPage> {
                           onSendMessage: (text) =>
                               _handleMessageSend(text, selectedModel),
                           onVoiceInput: null,
+                          onVoiceCall: _handleVoiceCall,
                           onFileAttachment: _handleFileAttachment,
                           onImageAttachment: _handleImageAttachment,
                           onCameraCapture: () =>

lib/features/chat/widgets/modern_chat_input.dart

@@ -60,6 +60,7 @@ class ModernChatInput extends ConsumerStatefulWidget {
   final Function(String) onSendMessage;
   final bool enabled;
   final Function()? onVoiceInput;
+  final Function()? onVoiceCall;
   final Function()? onFileAttachment;
   final Function()? onImageAttachment;
   final Function()? onCameraCapture;
@@ -69,6 +70,7 @@ class ModernChatInput extends ConsumerStatefulWidget {
     required this.onSendMessage,
     this.enabled = true,
     this.onVoiceInput,
+    this.onVoiceCall,
     this.onFileAttachment,
     this.onImageAttachment,
     this.onCameraCapture,
@@ -831,6 +833,10 @@ class _ModernChatInputState extends ConsumerState<ModernChatInput>
                 ),
               ),
               const SizedBox(width: Spacing.sm),
+              if (!_hasText && voiceAvailable && !isGenerating)
+                _buildMicButton(voiceAvailable),
+              if (!_hasText && voiceAvailable && !isGenerating)
+                const SizedBox(width: Spacing.sm),
               _buildPrimaryButton(
                 _hasText,
                 isGenerating,
@@ -911,6 +917,10 @@ class _ModernChatInputState extends ConsumerState<ModernChatInput>
               Row(
                 mainAxisSize: MainAxisSize.min,
                 children: [
+                  if (!_hasText && voiceAvailable && !isGenerating) ...[
+                    _buildMicButton(voiceAvailable),
+                    const SizedBox(width: Spacing.sm),
+                  ],
                   _buildPrimaryButton(
                     _hasText,
                     isGenerating,
@@ -1242,6 +1252,45 @@ class _ModernChatInputState extends ConsumerState<ModernChatInput>
     );
   }
 
+  Widget _buildMicButton(bool voiceAvailable) {
+    final bool enabledMic = widget.enabled && voiceAvailable;
+    return Tooltip(
+      message: AppLocalizations.of(context)!.voiceInput,
+      child: Opacity(
+        opacity: enabledMic ? Alpha.primary : Alpha.disabled,
+        child: Material(
+          color: Colors.transparent,
+          child: InkWell(
+            borderRadius: BorderRadius.circular(AppBorderRadius.circular),
+            onTap: enabledMic
+                ? () {
+                    HapticFeedback.selectionClick();
+                    _toggleVoice();
+                  }
+                : null,
+            child: SizedBox(
+              width: TouchTarget.minimum,
+              height: TouchTarget.minimum,
+              child: Icon(
+                Platform.isIOS ? CupertinoIcons.mic : Icons.mic,
+                size: IconSize.large,
+                color: _isRecording
+                    ? context.conduitTheme.buttonPrimary
+                    : (enabledMic
+                          ? context.conduitTheme.textPrimary.withValues(
+                              alpha: Alpha.strong,
+                            )
+                          : context.conduitTheme.textPrimary.withValues(
+                              alpha: Alpha.disabled,
+                            )),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
   Widget _buildPrimaryButton(
     bool hasText,
     bool isGenerating,
@@ -1296,7 +1345,7 @@ class _ModernChatInputState extends ConsumerState<ModernChatInput>
       );
     }
 
-    // If there's text, render SEND variant; otherwise render MIC variant
+    // If there's text, render SEND variant; otherwise render VOICE CALL variant
     if (hasText) {
       return Tooltip(
         message: enabled
@@ -1374,37 +1423,74 @@ class _ModernChatInputState extends ConsumerState<ModernChatInput>
       );
     }
 
-    // MIC variant when no text is present
+    // VOICE CALL variant when no text is present
-    final bool enabledMic = widget.enabled && voiceAvailable;
+    final bool enabledVoiceCall = widget.enabled && widget.onVoiceCall != null;
     return Tooltip(
-      message: AppLocalizations.of(context)!.voiceInput,
+      message: 'Voice Call',
       child: Opacity(
-        opacity: enabledMic ? Alpha.primary : Alpha.disabled,
+        opacity: enabledVoiceCall ? Alpha.primary : Alpha.disabled,
+        child: IgnorePointer(
+          ignoring: !enabledVoiceCall,
           child: Material(
             color: Colors.transparent,
             child: InkWell(
-            borderRadius: BorderRadius.circular(AppBorderRadius.circular),
+              borderRadius: BorderRadius.circular(radius),
-            onTap: enabledMic
+              onTap: enabledVoiceCall
                   ? () {
-                    HapticFeedback.selectionClick();
+                      PlatformUtils.lightHaptic();
-                    _toggleVoice();
+                      widget.onVoiceCall!();
                     }
                   : null,
-            child: SizedBox(
+              child: AnimatedContainer(
-              width: TouchTarget.minimum,
+                duration: const Duration(milliseconds: 160),
-              height: TouchTarget.minimum,
+                curve: Curves.easeOutCubic,
-              child: Icon(
+                width: buttonSize,
-                Platform.isIOS ? CupertinoIcons.mic : Icons.mic,
+                height: buttonSize,
-                size: IconSize.large,
+                decoration: BoxDecoration(
-                color: _isRecording
+                  color: enabledVoiceCall
                       ? context.conduitTheme.buttonPrimary
-                    : (enabledMic
+                      : context.conduitTheme.surfaceContainerHighest,
-                          ? context.conduitTheme.textPrimary.withValues(
+                  borderRadius: BorderRadius.circular(radius),
-                              alpha: Alpha.strong,
+                  border: Border.all(
+                    color: enabledVoiceCall
+                        ? context.conduitTheme.buttonPrimary.withValues(
+                            alpha: 0.8,
                           )
+                        : context.conduitTheme.cardBorder.withValues(
+                            alpha: 0.45,
+                          ),
+                    width: BorderWidth.thin,
+                  ),
+                  boxShadow: enabledVoiceCall
+                      ? <BoxShadow>[
+                          BoxShadow(
+                            color: context.conduitTheme.cardShadow.withValues(
+                              alpha:
+                                  Theme.of(context).brightness ==
+                                      Brightness.dark
+                                  ? 0.36
+                                  : 0.18,
+                            ),
+                            blurRadius: 18,
+                            spreadRadius: -6,
+                            offset: const Offset(0, 8),
+                          ),
+                        ]
+                      : const [],
+                ),
+                child: Center(
+                  child: Icon(
+                    Platform.isIOS
+                        ? CupertinoIcons.waveform
+                        : Icons.graphic_eq,
+                    size: IconSize.large,
+                    color: enabledVoiceCall
+                        ? context.conduitTheme.buttonPrimaryText
                         : context.conduitTheme.textPrimary.withValues(
                             alpha: Alpha.disabled,
-                            )),
+                          ),
+                  ),
+                ),
               ),
             ),
           ),