From e5d850d76c87a3e77f5c8cb0db9a0e2ff4b95e66 Mon Sep 17 00:00:00 2001
From: PB <pbfordev@gmail.com>
Date: Tue, 9 Apr 2019 16:13:39 +0200
Subject: [PATCH] Improve returning wxSYS_CARET_* metrics in wxMSW

The documentation stated that (a) wxSYS_CARET_{ON|OFF}_MSEC  settings
were not supported on MSW and (b) if a setting was not supported a
negative value was returned. However, when calling
wxSystemSettings::GetMetric(wxSYS_CARET_{ON|OFF}_MSEC), not only the
method asserted but 0 was returned instead of a negative value.

Fix this by using the value returned by ::GetCaretBlinkTime() for
wxSYS_CARET_{ON|OFF}_MSEC.

The documentation for wxSYS_CARET_TIMEOUT_MSEC does not list any
platform limitations; however, attempting to obtain this value resulted
in an assert and 0 returned. Fix this by returning -1. Returning -1 may
not the be the ideal solution, but there is no value reserved for the
setting not being supported and the caret on MSW usually blinks.

Closes https://github.com/wxWidgets/wxWidgets/pull/1285
---
 interface/wx/settings.h |  5 ++---
 src/msw/settings.cpp    | 24 +++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/interface/wx/settings.h b/interface/wx/settings.h
index 925c6aa9c4..9a6d8621e3 100644
--- a/interface/wx/settings.h
+++ b/interface/wx/settings.h
@@ -197,7 +197,7 @@ enum wxSystemMetric
         Time, in milliseconds, for how long a blinking caret should
         stay visible during a single blink cycle before it disappears.
         If this value is negative, the platform does not support the
-        user setting.  Implemented only on GTK+ and MacOS X.
+        user setting.
 
         @since 3.1.1
     */
@@ -208,8 +208,7 @@ enum wxSystemMetric
         stay invisible during a single blink cycle before it reappears.
         If this value is zero, carets should be visible all the time
         instead of blinking.  If the value is negative, the platform
-        does not support the user setting.  Implemented only on GTK+
-        and MacOS X.
+        does not support the user setting.
 
         @since 3.1.1
     */
diff --git a/src/msw/settings.cpp b/src/msw/settings.cpp
index 4b8534f18b..3377b5b080 100644
--- a/src/msw/settings.cpp
+++ b/src/msw/settings.cpp
@@ -253,7 +253,10 @@ static const int gs_metricsMap[] =
     SM_PENWINDOWS,
     SM_SHOWSOUNDS,
     SM_SWAPBUTTON,
-    -1   // wxSYS_DCLICK_MSEC - not available as system metric
+    -1,   // wxSYS_DCLICK_MSEC - not available as system metric
+    -1,   // wxSYS_CARET_ON_MSEC - not available as system metric
+    -1,   // wxSYS_CARET_OFF_MSEC - not available as system metric
+    -1    // wxSYS_CARET_TIMEOUT_MSEC - not available as system metric
 };
 
 // Get a system metric, e.g. scrollbar size
@@ -268,6 +271,25 @@ int wxSystemSettingsNative::GetMetric(wxSystemMetric index, wxWindow* WXUNUSED(w
         return ::GetDoubleClickTime();
     }
 
+    // return the caret blink time for both
+    // wxSYS_CARET_ON_MSEC and wxSYS_CARET_OFF_MSEC
+    if ( index == wxSYS_CARET_ON_MSEC || index == wxSYS_CARET_OFF_MSEC )
+    {
+        const UINT blinkTime = ::GetCaretBlinkTime();
+
+        if ( blinkTime == 0 ) // error
+        {
+            return -1;
+        }
+        
+        if ( blinkTime == INFINITE ) // caret does not blink
+        {
+            return 0;
+        }
+
+        return blinkTime;
+    }
+
     int indexMSW = gs_metricsMap[index];
     if ( indexMSW == -1 )
     {