Add a setting to flash the pane when BEL is emitted

src/cascadia/TerminalApp/Pane.cpp

@@ -378,8 +378,17 @@ void Pane::_ControlWarningBellHandler(const winrt::Windows::Foundation::IInspect
                 PlaySound(soundAlias, NULL, SND_ALIAS_ID | SND_ASYNC | SND_SENTRY);
             }
 
-            // raise the event with the bool value corresponding to the visual flag
-            _PaneRaiseBellHandlers(nullptr, WI_IsFlagSet(paneProfile.BellStyle(), winrt::Microsoft::Terminal::Settings::Model::BellStyle::Visual));
+            if (WI_IsFlagSet(paneProfile.BellStyle(), winrt::Microsoft::Terminal::Settings::Model::BellStyle::Visual) ||
+                WI_IsFlagSet(paneProfile.BellStyle(), winrt::Microsoft::Terminal::Settings::Model::BellStyle::Window))
+            {
+                _control.InvertScreenColors();
+            }
+
+            const auto flashTaskbar = WI_IsFlagSet(paneProfile.BellStyle(), winrt::Microsoft::Terminal::Settings::Model::BellStyle::Visual) ||
+                                      WI_IsFlagSet(paneProfile.BellStyle(), winrt::Microsoft::Terminal::Settings::Model::BellStyle::Taskbar);
+
+            // raise the event with the bool value corresponding to the taskbar or visual flag
+            _PaneRaiseBellHandlers(nullptr, flashTaskbar);
         }
     }
 }

src/cascadia/TerminalControl/TermControl.cpp

@@ -77,6 +77,7 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
         _touchAnchor{ std::nullopt },
         _cursorTimer{},
         _blinkTimer{},
+        _invertTimer{},
         _lastMouseClickTimestamp{},
         _lastMouseClickPos{},
         _selectionNeedsToBeCopied{ false },
@@ -3254,6 +3255,32 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
         return _terminal->GetTaskbarProgress();
     }
 
+    winrt::fire_and_forget TermControl::InvertScreenColors()
+    {
+        if (!_invertTimer)
+        {
+            co_await winrt::resume_foreground(Dispatcher());
+
+            DispatcherTimer invertTimer;
+            invertTimer.Interval(std::chrono::milliseconds(2000));
+            invertTimer.Tick({ get_weak(), &TermControl::_InvertTimerTick });
+            invertTimer.Start();
+            _invertTimer.emplace(std::move(invertTimer));
+            _terminal->SetScreenMode(true);
+        }
+    }
+
+    void TermControl::_InvertTimerTick(Windows::Foundation::IInspectable const& /* sender */,
+                                       Windows::Foundation::IInspectable const& /* e */)
+    {
+        if (_invertTimer)
+        {
+            _terminal->SetScreenMode(false);
+            _invertTimer.value().Stop();
+            _invertTimer = std::nullopt;
+        }
+    }
+
     // Method Description:
     // - Checks whether the control is in a read-only mode (in this mode node input is sent to connection).
     // Return Value:

src/cascadia/TerminalControl/TermControl.h

@@ -166,6 +166,8 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
         const size_t TaskbarState() const noexcept;
         const size_t TaskbarProgress() const noexcept;
 
+        winrt::fire_and_forget InvertScreenColors();
+
         bool ReadOnly() const noexcept;
         void ToggleReadOnly();
 
@@ -241,6 +243,7 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
 
         std::optional<Windows::UI::Xaml::DispatcherTimer> _cursorTimer;
         std::optional<Windows::UI::Xaml::DispatcherTimer> _blinkTimer;
+        std::optional<Windows::UI::Xaml::DispatcherTimer> _invertTimer;
 
         // If this is set, then we assume we are in the middle of panning the
         //      viewport via touch input.
@@ -297,6 +300,7 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
 
         void _CursorTimerTick(Windows::Foundation::IInspectable const& sender, Windows::Foundation::IInspectable const& e);
         void _BlinkTimerTick(Windows::Foundation::IInspectable const& sender, Windows::Foundation::IInspectable const& e);
+        void _InvertTimerTick(Windows::Foundation::IInspectable const& sender, Windows::Foundation::IInspectable const& e);
         void _SetEndSelectionPointAtCursor(Windows::Foundation::Point const& cursorPosition);
         void _SendInputToConnection(const winrt::hstring& wstr);
         void _SendInputToConnection(std::wstring_view wstr);

src/cascadia/TerminalControl/TermControl.idl

@@ -114,6 +114,8 @@ namespace Microsoft.Terminal.TerminalControl
         UInt64 TaskbarState { get; };
         UInt64 TaskbarProgress { get; };
 
+        void InvertScreenColors();
+
         String WorkingDirectory { get; };
 
         Windows.Foundation.IReference<Windows.UI.Color> TabColor { get; };

src/cascadia/TerminalSettingsModel/Profile.idl

@@ -15,6 +15,8 @@ namespace Microsoft.Terminal.Settings.Model
     {
         Audible = 0x1,
         Visual = 0x2,
+        Window = 0x4,
+        Taskbar = 0x8,
         All = 0xffffffff
     };
 

src/cascadia/TerminalSettingsModel/TerminalSettingsSerializationHelpers.h

@@ -50,10 +50,12 @@ JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::TerminalControl::ScrollbarState)
 
 JSON_FLAG_MAPPER(::winrt::Microsoft::Terminal::Settings::Model::BellStyle)
 {
-    static constexpr std::array<pair_type, 4> mappings = {
+    static constexpr std::array<pair_type, 6> mappings = {
         pair_type{ "none", AllClear },
         pair_type{ "audible", ValueType::Audible },
         pair_type{ "visual", ValueType::Visual },
+        pair_type{ "window", ValueType::Window },
+        pair_type{ "taskbar", ValueType::Taskbar },
         pair_type{ "all", AllSet },
     };