moved sleep prevention code for further abstraction, implemented macOS

app/widget/viewer/viewer.cpp

@@ -30,10 +30,6 @@
 #include <QtMath>
 #include <QVBoxLayout>
 
-#ifdef _WIN32
-#include "winbase.h"
-#endif
-
 #include "audio/audiomanager.h"
 #include "common/clamp.h"
 #include "common/power.h"
@@ -44,6 +40,7 @@
 #include "node/project/project.h"
 #include "render/rendermanager.h"
 #include "task/taskmanager.h"
+#include "viewerpreventsleep.h"
 #include "widget/menu/menu.h"
 #include "window/mainwindow/mainwindow.h"
 
@@ -707,9 +704,7 @@ void ViewerWidget::PlayInternal(int speed, bool in_to_out_only)
     }
   }
   // Force screen to stay awake
-#ifdef _WIN32
-  SetThreadExecutionState(ES_DISPLAY_REQUIRED | ES_CONTINUOUS);
-#endif
+  PreventSleep(true);
 }
 
 void ViewerWidget::PauseInternal()
@@ -752,9 +747,7 @@ void ViewerWidget::PauseInternal()
   prequeuing_audio_ = 0;
 
   // Reset screen timeout timer
-#ifdef _WIN32
-  SetThreadExecutionState(ES_CONTINUOUS);
-#endif
+  PreventSleep(false);
 }
 
 void ViewerWidget::PushScrubbedAudio()