comments comments comments

src/cascadia/TerminalControl/ControlCore.cpp

@@ -1683,11 +1683,22 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         }
     }
 
+    // Method Description:
+    // - When the control gains focus, it needs to tell ConPTY about this.
+    //   Usually, these sequences are reserved for applications that
+    //   specifically request SET_FOCUS_EVENT_MOUSE, ?1004h. ConPTY uses this
+    //   sequence REGARDLESS to communicate if the control was focused or not.
+    // - Even if a client application disables this mode, the Terminal & conpty
+    //   should always request this from the hostind terminal (and just ignore
+    //   internally to ConPTY).
+    // - Full support for this sequence is tracked in GH#11682.
+    // - This is related to work done for GH#2988.
     void ControlCore::GotFocus()
     {
         _connection.WriteInput(L"\x1b[I");
     }
 
+    // See GotFocus.
     void ControlCore::LostFocus()
     {
         _connection.WriteInput(L"\x1b[O");

src/host/CursorBlinker.cpp

@@ -82,8 +82,10 @@ void CursorBlinker::TimerRoutine(SCREEN_INFORMATION& ScreenInfo) const noexcept
     auto& cursor = buffer.GetCursor();
     auto& gci = ServiceLocator::LocateGlobals().getConsoleInformation();
     auto* const pAccessibilityNotifier = ServiceLocator::LocateAccessibilityNotifier();
+    const bool inConpty{ gci.IsInVtIoMode() };
 
-    if (!WI_IsFlagSet(gci.Flags, CONSOLE_HAS_FOCUS))
+    // GH#2988: ConPTY can now be focused, but it doesn't need to do any of this work either.
+    if (inConpty || !WI_IsFlagSet(gci.Flags, CONSOLE_HAS_FOCUS))
     {
         goto DoScroll;
     }

src/host/outputStream.cpp

@@ -893,9 +893,26 @@ void ConhostInternalGetSet::UpdateSoftFont(const gsl::span<const uint16_t> bitPa
     }
 }
 
+// Method Description:
+// - Inform the console that the window is focused. This is used by ConPTY.
+//   Terminals can send ConPTY a FocusIn/FocusOut sequence on the input pipe,
+//   which will end up here. This will update the console's internal tracker if
+//   it's focused or not, as to match the end-terminal's state.
+// - Used to call ConsoleControl(ConsoleSetForeground,...).
+// - Full support for this sequence is tracked in GH#11682.
+// Arguments:
+// - bitPattern - An array of scanlines representing all the glyphs in the font.
+// - cellSize - The cell size for an individual glyph.
+// - centeringHint - The horizontal extent that glyphs are offset from center.
+// Return Value:
+// - <none>
 void ConhostInternalGetSet::FocusChanged(const bool focused)
 {
     auto& g = ServiceLocator::LocateGlobals();
     auto& gci = g.getConsoleInformation();
+    WI_UpdateFlag(gci.Flags, CONSOLE_HAS_FOCUS, focused);
     gci.ProcessHandleList.ModifyConsoleProcessFocus(focused);
+
+    // Theoretically, this could be propogated as a focus event as well, to the
+    // input buffer. That should be considered when implementing GH#11682.
 }

src/server/IoDispatchers.cpp

@@ -456,9 +456,22 @@ PCONSOLE_API_MSG IoDispatchers::ConsoleHandleConnectionRequest(_In_ PCONSOLE_API
         return pReceiveMsg;
     }
 
+    // For future code archeologists: GH#2988
+    //
+    // Here, the console calls ConsoleControl(ConsoleSetForeground,...) with a
+    // flag depending on if the console is focused or not. This is surprisingly
+    // load bearing. This allows windows spawned by console processes to bring
+    // themselves to the foreground _when the console is focused_.
+    // (Historically, this is also called in the WndProc, when focus changes).
+    //
+    // Notably, before 2022, ConPTY was _never_ focused, so windows could never
+    // bring themselves to the foreground when run from a ConPTY console. We're
+    // not blanket granting the SetForeground right to all console apps when run
+    // in ConPTY. It's the responsibility of the hosting terminal emulator to
+    // always tell ConPTY when a particular instance is focused.
     const bool hasFocus{ WI_IsFlagSet(gci.Flags, CONSOLE_HAS_FOCUS) };
-    const auto grantFG{ hasFocus };
-    gci.ProcessHandleList.ModifyConsoleProcessFocus(grantFG);
+    const auto grantSetForeground{ hasFocus };
+    gci.ProcessHandleList.ModifyConsoleProcessFocus(grantSetForeground);
 
     // Create the handles.