Display connection state in tab and add context menu entry for restarting connection (#15760)

## Summary of the Pull Request
When a connection is Closed, show an indicator in the respective tab.
When the active pane's connection is Closed, show a "Restart Connection"
action in the right-click context menu and in the tab context menu.

## Validation Steps Performed
- Force close a connection, check the indicator is shown in the tab.
- Right-click on pane shows the Restart Connection action if its
connection is closed
- Right-click on tab shows the Restart Connection action if the active
pane's connection is closed
- Indicator is cleared after connection is restarted (no panes in closed
state)

## PR Checklist
- [x] Closes #14909 
- [x] Tests added/passed
- [ ] Documentation updated
- [ ] Schema updated (if necessary)

src/cascadia/TerminalApp/Pane.cpp

@@ -1384,6 +1384,18 @@ Profile Pane::GetFocusedProfile()
     return lastFocused ? lastFocused->_profile : nullptr;
 }
 
+// Method Description:
+// - Returns true if the connection state of this pane is closed. If this Pane is not a leaf this will
+//   return false.
+// Arguments:
+// - <none>
+// Return Value:
+// - true if the connection state of this Pane is closed.
+bool Pane::IsConnectionClosed() const
+{
+    return _control && _control.ConnectionState() >= ConnectionState::Closed;
+}
+
 // Method Description:
 // - Returns true if this pane was the last pane to be focused in a tree of panes.
 // Arguments:

src/cascadia/TerminalApp/Pane.h

@@ -75,6 +75,7 @@ public:
     winrt::Microsoft::Terminal::Control::TermControl GetLastFocusedTerminalControl();
     winrt::Microsoft::Terminal::Control::TermControl GetTerminalControl();
     winrt::Microsoft::Terminal::Settings::Model::Profile GetFocusedProfile();
+    bool IsConnectionClosed() const;
 
     // Method Description:
     // - If this is a leaf pane, return its profile.

src/cascadia/TerminalApp/Resources/en-US/Resources.resw

@@ -891,4 +891,10 @@
   <data name="CmdAppendCommandLineDesc" xml:space="preserve">
     <value>If set, the command will be appended to the profile's default command instead of replacing it.</value>
   </data>
+  <data name="RestartConnectionText" xml:space="preserve">
+    <value>Restart Connection</value>
+  </data>
+  <data name="RestartConnectionToolTip" xml:space="preserve">
+    <value>Restart the active pane connection</value>
+  </data>
 </root>

src/cascadia/TerminalApp/TabHeaderControl.xaml

@@ -43,6 +43,12 @@
                   FontSize="12"
                   Glyph=""
                   Visibility="{x:Bind TabStatus.IsReadOnlyActive, Mode=OneWay}" />
+        <FontIcon x:Name="HeaderClosedIcon"
+                  Margin="0,0,8,0"
+                  FontFamily="{ThemeResource SymbolThemeFontFamily}"
+                  FontSize="12"
+                  Glyph="&#xEA39;"
+                  Visibility="{x:Bind TabStatus.IsConnectionClosed, Mode=OneWay}" />
         <FontIcon x:Name="HeaderBroadcastIcon"
                   Margin="0,0,8,0"
                   FontFamily="{ThemeResource SymbolThemeFontFamily}"

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -4810,8 +4810,7 @@ namespace winrt::TerminalApp::implementation
                                             const bool withSelection)
     {
         // withSelection can be used to add actions that only appear if there's
-        // selected text, like "search the web". In this initial draft, it's not
-        // actually augmented by the TerminalPage, so it's left commented out.
+        // selected text, like "search the web"
 
         const auto& menu{ sender.try_as<MUX::Controls::CommandBarFlyout>() };
         if (!menu)
@@ -4864,6 +4863,14 @@ namespace winrt::TerminalApp::implementation
             makeItem(RS_(L"PaneClose"), L"\xE89F", ActionAndArgs{ ShortcutAction::ClosePane, nullptr });
         }
 
+        if (const auto pane{ _GetFocusedTabImpl()->GetActivePane() })
+        {
+            if (pane->IsConnectionClosed())
+            {
+                makeItem(RS_(L"RestartConnectionText"), L"\xE72C", ActionAndArgs{ ShortcutAction::RestartConnection, nullptr });
+            }
+        }
+
         if (withSelection)
         {
             makeItem(RS_(L"SearchWebText"), L"\xF6FA", ActionAndArgs{ ShortcutAction::SearchForText, nullptr });

src/cascadia/TerminalApp/TerminalTab.cpp

@@ -15,6 +15,7 @@ using namespace winrt;
 using namespace winrt::Windows::UI::Xaml;
 using namespace winrt::Windows::UI::Core;
 using namespace winrt::Microsoft::Terminal::Control;
+using namespace winrt::Microsoft::Terminal::TerminalConnection;
 using namespace winrt::Microsoft::Terminal::Settings::Model;
 using namespace winrt::Microsoft::UI::Xaml::Controls;
 using namespace winrt::Windows::System;
@@ -35,6 +36,7 @@ namespace winrt::TerminalApp::implementation
         _activePane = nullptr;
 
         _closePaneMenuItem.Visibility(WUX::Visibility::Collapsed);
+        _restartConnectionMenuItem.Visibility(WUX::Visibility::Collapsed);
 
         auto firstId = _nextPaneId;
 
@@ -890,6 +892,7 @@ namespace winrt::TerminalApp::implementation
             control.TitleChanged(events.titleToken);
             control.TabColorChanged(events.colorToken);
             control.SetTaskbarProgress(events.taskbarToken);
+            control.ConnectionStateChanged(events.stateToken);
             control.ReadOnlyChanged(events.readOnlyToken);
             control.FocusFollowMouseRequested(events.focusToken);
 
@@ -949,6 +952,14 @@ namespace winrt::TerminalApp::implementation
             }
         });
 
+        events.stateToken = control.ConnectionStateChanged([dispatcher, weakThis](auto&&, auto&&) -> winrt::fire_and_forget {
+            co_await wil::resume_foreground(dispatcher);
+            if (auto tab{ weakThis.get() })
+            {
+                tab->_UpdateConnectionClosedState();
+            }
+        });
+
         events.readOnlyToken = control.ReadOnlyChanged([dispatcher, weakThis](auto&&, auto&&) -> winrt::fire_and_forget {
             co_await wil::resume_foreground(dispatcher);
             if (auto tab{ weakThis.get() })
@@ -1054,6 +1065,40 @@ namespace winrt::TerminalApp::implementation
         _TaskbarProgressChangedHandlers(nullptr, nullptr);
     }
 
+    // Method Description:
+    // - Set an indicator on the tab if any pane is in a closed connection state.
+    // - Show/hide the Restart Connection context menu entry depending on active pane's state.
+    // Arguments:
+    // - <none>
+    // Return Value:
+    // - <none>
+    void TerminalTab::_UpdateConnectionClosedState()
+    {
+        ASSERT_UI_THREAD();
+
+        if (_rootPane)
+        {
+            const bool isClosed = _rootPane->WalkTree([&](const auto& p) {
+                return p->IsConnectionClosed();
+            });
+
+            _tabStatus.IsConnectionClosed(isClosed);
+        }
+
+        if (_activePane)
+        {
+            _restartConnectionMenuItem.Visibility(_activePane->IsConnectionClosed() ?
+                                                      WUX::Visibility::Visible :
+                                                      WUX::Visibility::Collapsed);
+        }
+    }
+
+    void TerminalTab::_RestartActivePaneConnection()
+    {
+        ActionAndArgs restartConnection{ ShortcutAction::RestartConnection, nullptr };
+        _dispatch.DoAction(*this, restartConnection);
+    }
+
     // Method Description:
     // - Mark the given pane as the active pane in this tab. All other panes
     //   will be marked as inactive. We'll also update our own UI state to
@@ -1072,6 +1117,7 @@ namespace winrt::TerminalApp::implementation
         // Update our own title text to match the newly-active pane.
         UpdateTitle();
         _UpdateProgressState();
+        _UpdateConnectionClosedState();
 
         // We need to move the pane to the top of our mru list
         // If its already somewhere in the list, remove it first
@@ -1393,6 +1439,28 @@ namespace winrt::TerminalApp::implementation
             Automation::AutomationProperties::SetHelpText(findMenuItem, findToolTip);
         }
 
+        Controls::MenuFlyoutItem restartConnectionMenuItem = _restartConnectionMenuItem;
+        {
+            // "Restart Connection"
+            Controls::FontIcon restartConnectionSymbol;
+            restartConnectionSymbol.FontFamily(Media::FontFamily{ L"Segoe Fluent Icons, Segoe MDL2 Assets" });
+            restartConnectionSymbol.Glyph(L"\xE72C");
+
+            restartConnectionMenuItem.Click([weakThis](auto&&, auto&&) {
+                if (auto tab{ weakThis.get() })
+                {
+                    tab->_RestartActivePaneConnection();
+                }
+            });
+            restartConnectionMenuItem.Text(RS_(L"RestartConnectionText"));
+            restartConnectionMenuItem.Icon(restartConnectionSymbol);
+
+            const auto restartConnectionToolTip = RS_(L"RestartConnectionToolTip");
+
+            WUX::Controls::ToolTipService::SetToolTip(restartConnectionMenuItem, box_value(restartConnectionToolTip));
+            Automation::AutomationProperties::SetHelpText(restartConnectionMenuItem, restartConnectionToolTip);
+        }
+
         // Build the menu
         Controls::MenuFlyout contextMenuFlyout;
         Controls::MenuFlyoutSeparator menuSeparator;
@@ -1403,6 +1471,7 @@ namespace winrt::TerminalApp::implementation
         contextMenuFlyout.Items().Append(moveTabToNewWindowMenuItem);
         contextMenuFlyout.Items().Append(exportTabMenuItem);
         contextMenuFlyout.Items().Append(findMenuItem);
+        contextMenuFlyout.Items().Append(restartConnectionMenuItem);
         contextMenuFlyout.Items().Append(menuSeparator);
 
         // GH#5750 - When the context menu is dismissed with ESC, toss the focus

src/cascadia/TerminalApp/TerminalTab.h

@@ -109,6 +109,7 @@ namespace winrt::TerminalApp::implementation
         std::shared_ptr<Pane> _zoomedPane{ nullptr };
 
         Windows::UI::Xaml::Controls::MenuFlyoutItem _closePaneMenuItem;
+        Windows::UI::Xaml::Controls::MenuFlyoutItem _restartConnectionMenuItem;
 
         winrt::hstring _lastIconPath{};
         std::optional<winrt::Windows::UI::Color> _runtimeTabColor{};
@@ -125,6 +126,7 @@ namespace winrt::TerminalApp::implementation
             winrt::event_token titleToken;
             winrt::event_token colorToken;
             winrt::event_token taskbarToken;
+            winrt::event_token stateToken;
             winrt::event_token readOnlyToken;
             winrt::event_token focusToken;
 
@@ -171,6 +173,9 @@ namespace winrt::TerminalApp::implementation
 
         void _UpdateProgressState();
 
+        void _UpdateConnectionClosedState();
+        void _RestartActivePaneConnection();
+
         void _DuplicateTab();
 
         virtual winrt::Windows::UI::Xaml::Media::Brush _BackgroundBrush() override;

src/cascadia/TerminalApp/TerminalTabStatus.h

@@ -12,6 +12,7 @@ namespace winrt::TerminalApp::implementation
         TerminalTabStatus() = default;
 
         WINRT_CALLBACK(PropertyChanged, Windows::UI::Xaml::Data::PropertyChangedEventHandler);
+        WINRT_OBSERVABLE_PROPERTY(bool, IsConnectionClosed, _PropertyChangedHandlers);
         WINRT_OBSERVABLE_PROPERTY(bool, IsPaneZoomed, _PropertyChangedHandlers);
         WINRT_OBSERVABLE_PROPERTY(bool, IsProgressRingActive, _PropertyChangedHandlers);
         WINRT_OBSERVABLE_PROPERTY(bool, IsProgressRingIndeterminate, _PropertyChangedHandlers);

src/cascadia/TerminalApp/TerminalTabStatus.idl

@@ -7,6 +7,7 @@ namespace TerminalApp
     {
         TerminalTabStatus();
 
+        Boolean IsConnectionClosed { get; set; };
         Boolean IsPaneZoomed { get; set; };
         Boolean IsProgressRingActive { get; set; };
         Boolean IsProgressRingIndeterminate { get; set; };