Dark mode theme only for Windows

src/qt/qt_main.cpp

@@ -30,6 +30,8 @@
 #include <QFont>
 #include <QDialog>
 #include <QMessageBox>
+#include <QFile>
+#include <QTextStream>
 
 #ifdef QT_STATIC
 /* Static builds need plugin imports */
@@ -154,6 +156,10 @@ main_thread_fn()
 
 static std::thread *main_thread;
 
+#ifdef Q_OS_WINDOWS
+extern bool windows_is_light_theme();
+#endif
+
 int
 main(int argc, char *argv[])
 {
@@ -168,6 +174,22 @@ main(int argc, char *argv[])
     QApplication app(argc, argv);
     QLocale::setDefault(QLocale::C);
 
+#ifdef Q_OS_WINDOWS
+    Q_INIT_RESOURCE(darkstyle);
+
+    if (!windows_is_light_theme()) {
+        QFile f(":qdarkstyle/dark/darkstyle.qss");
+
+        if (!f.exists())   {
+            printf("Unable to set stylesheet, file not found\n");
+        } else   {
+            f.open(QFile::ReadOnly | QFile::Text);
+            QTextStream ts(&f);
+            qApp->setStyleSheet(ts.readAll());
+        }
+    }
+#endif
+
     qt_set_sequence_auto_mnemonic(false);
     Q_INIT_RESOURCE(qt_resources);
     Q_INIT_RESOURCE(qt_translations);