lite-xl · sprainbrains · Sep 2, 2021 · Sep 2, 2021 · Sep 2, 2021 · Sep 7, 2021
diff --git a/meson.build b/meson.build
@@ -160,7 +160,13 @@ if not get_option('source-only')
         default_options: default_fallback_options + sdl_options
     )
 
-    lite_deps = [lua_dep, sdl_dep, freetype_dep, pcre2_dep, libm, libdl]
+    if host_machine.system() == 'windows'
+        win_dep = cc.find_library('dwmapi', required : true)
+    else
+        win_dep = cc.find_library('dwmapi', required : false)
+    endif
+
+    lite_deps = [lua_dep, sdl_dep, freetype_dep, pcre2_dep, libm, libdl, win_dep]
 endif
 #===============================================================================
 # Install Configuration

diff --git a/src/api/api.c b/src/api/api.c
@@ -23,3 +23,22 @@ void api_load_libs(lua_State *L) {
     luaL_requiref(L, libs[i].name, libs[i].func, 1);
 }
 
+#ifdef _WIN32
+int api_windows_dark_theme_activated()
+ {
+     DWORD   type;
+     DWORD   value;
+     DWORD   count = 4;
+     LSTATUS st = RegGetValue(
+         HKEY_CURRENT_USER,
+         TEXT("Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize"),
+         TEXT("AppsUseLightTheme"),
+         RRF_RT_REG_DWORD,
+         &type,
+         &value,
+         &count );
+     if ( st == ERROR_SUCCESS && type == REG_DWORD )
+         return value == 0? 1 : 0;
+     return 0;
+ }
+ #endif
diff --git a/src/api/api.h b/src/api/api.h
@@ -14,4 +14,11 @@
 
 void api_load_libs(lua_State *L);
 
+#ifdef _WIN32
+  #define WINDOWS_DARK_MODE_BEFORE_20H1 19
+  #define WINDOWS_DARK_MODE 20
+  #include <windows.h>
+  int api_windows_dark_theme_activated();
+#endif
+
 #endif
diff --git a/src/api/system.c b/src/api/system.c
@@ -12,6 +12,8 @@
   #include <direct.h>
   #include <windows.h>
   #include <fileapi.h>
+  #include "SDL_syswm.h"
+  #include <dwmapi.h>
   #include "../utfconv.h"
 
   // Windows does not define the S_ISREG and S_ISDIR macros in stat.h, so we do.
@@ -174,6 +176,11 @@ static int f_poll_event(lua_State *L) {
   SDL_Event e;
   SDL_Event event_plus;
 
+#ifdef _WIN32
+  if (SDL_GetEventState(SDL_SYSWMEVENT) == SDL_DISABLE)
+    SDL_EventState(SDL_SYSWMEVENT, SDL_ENABLE);
+#endif
+
 top:
   if ( !SDL_PollEvent(&e) ) {
     return 0;
@@ -183,7 +190,30 @@ static int f_poll_event(lua_State *L) {
     case SDL_QUIT:
       lua_pushstring(L, "quit");
       return 1;
+
+#ifdef _WIN32
+     case SDL_SYSWMEVENT:      
+       if (e.syswm.msg->msg.win.msg == WM_SETTINGCHANGE) {
+         HWND hwnd = e.syswm.msg->msg.win.hwnd;
+         LPARAM lParam = e.syswm.msg->msg.win.lParam;
+         if (lParam) {
+           int current_immersive_mode = 0;
+           if(DwmGetWindowAttribute(hwnd, WINDOWS_DARK_MODE_BEFORE_20H1, &current_immersive_mode, 4) != FACILITY_NULL)
+             DwmGetWindowAttribute(hwnd, WINDOWS_DARK_MODE, &current_immersive_mode, 4);
+
+           int current_dark_mode = api_windows_dark_theme_activated();
+
+           if (current_dark_mode != current_immersive_mode) {
+             if (DwmSetWindowAttribute(hwnd, WINDOWS_DARK_MODE_BEFORE_20H1, &current_dark_mode, 4) != 0)
+               DwmSetWindowAttribute(hwnd, WINDOWS_DARK_MODE, &current_dark_mode, 4);
+
+           }
+
+         }
+       }
+       return 0;
 
+ #endif
     case SDL_WINDOWEVENT:
       if (e.window.event == SDL_WINDOWEVENT_RESIZED) {
         ren_resize_window(&window_renderer);

diff --git a/src/main.c b/src/main.c
@@ -9,6 +9,8 @@
 
 #ifdef _WIN32
   #include <windows.h>
+  #include "SDL_syswm.h"
+  #include <dwmapi.h>
 #elif defined(__linux__)
   #include <unistd.h>
 #elif defined(__APPLE__)
@@ -29,6 +31,16 @@ static double get_scale(void) {
   return 1.0;
 }
 
+#ifdef _WIN32
+static HWND GetWindowHandle(SDL_Window* window){
+    SDL_SysWMinfo sysInfo;
+
+    SDL_VERSION(&sysInfo.version);
+    SDL_GetWindowWMInfo(window, &sysInfo);
+    return sysInfo.info.win.window;
+}
+#endif
+
 
 static void get_exe_filename(char *buf, int sz) {
 #if _WIN32
@@ -176,6 +188,13 @@ int main(int argc, char **argv) {
   window = SDL_CreateWindow(
     "", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, dm.w * 0.8, dm.h * 0.8,
     SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI | SDL_WINDOW_HIDDEN);
+#ifdef _WIN32
+   HWND handle = GetWindowHandle(window);
+   int mode = api_windows_dark_theme_activated();
+
+   if (DwmSetWindowAttribute(handle, WINDOWS_DARK_MODE_BEFORE_20H1, &mode, 4) != 0)
+     DwmSetWindowAttribute(handle, WINDOWS_DARK_MODE, &mode, 4);
+#endif
   init_window_icon();
   if (!window) {
     fprintf(stderr, "Error creating lite-xl window: %s", SDL_GetError());