libadwaita theme support

libadwaita-theming.patch

diff --git a/src/adw-style-manager.c b/src/adw-style-manager.c
index ae1a858d..c5b5ac73 100644
--- a/src/adw-style-manager.c
+++ b/src/adw-style-manager.c
@@ -14,6 +14,8 @@
 #include "adw-settings-private.h"
 #include <gtk/gtk.h>
 
+int file_exists(const char *fname);
+
 #define SWITCH_DURATION 250
 
 /**
@@ -165,7 +167,6 @@ update_stylesheet (AdwStyleManager *self)
       gtk_css_provider_load_from_resource (self->provider,
                                            "/org/gnome/Adwaita/styles/base.css");
   }
-
   if (self->colors_provider) {
     if (self->dark)
       gtk_css_provider_load_from_resource (self->colors_provider,
@@ -175,12 +176,41 @@ update_stylesheet (AdwStyleManager *self)
                                            "/org/gnome/Adwaita/styles/defaults-light.css");
   }
 
+  /* Theming support */
+  gchar *thm;
+  GSettings *settings;
+  settings = g_settings_new ("org.gnome.desktop.interface");
+  g_settings_get (settings, "gtk-theme", "s", &thm);
+  char theme_path[1024];
+  sprintf(theme_path,"/usr/share/themes/%s/gtk-4.0/gtk.css",(char*)thm);
+  GFile *file = NULL;
+  if (file_exists(theme_path)){
+      file=g_file_new_for_path(theme_path);
+  }
+  sprintf(theme_path,"%s/.themes/%s/gtk-4.0/gtk.css",getenv("HOME"),(char*)thm);
+  if (file_exists(theme_path)){
+      file=g_file_new_for_path(theme_path);
+  }
+  if (G_IS_FILE(file)){
+      gtk_css_provider_load_from_file(self->colors_provider,file);
+  }
+  
+  
   self->animation_timeout_id =
     g_timeout_add (SWITCH_DURATION,
                    G_SOURCE_FUNC (enable_animations_cb),
                    self);
 }
-
+int file_exists(const char *fname)
+{
+    FILE *file;
+    if ((file = fopen(fname, "r")))
+    {
+        fclose(file);
+        return 1;
+    }
+    return 0;
+}
 static gboolean
 get_is_dark (AdwStyleManager *self)
 {