--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Deprecated/Platforms/Wasm/Defaults.h	Wed Apr 29 20:45:14 2020 +0200
@@ -0,0 +1,82 @@
+#pragma once
+
+#include <emscripten/emscripten.h>
+
+#include "../../Framework/Deprecated/Viewport/WidgetViewport.h"
+#include "../../Framework/Deprecated/Widgets/LayoutWidget.h"
+#include <Applications/IStoneApplication.h>
+#include <Platforms/Wasm/WasmPlatformApplicationAdapter.h>
+
+typedef Deprecated::WidgetViewport* ViewportHandle; // the objects exchanged between JS and C++
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+  
+  // JS methods accessible from C++
+  extern void ScheduleWebViewportRedrawFromCpp(ViewportHandle cppViewportHandle);
+  extern void UpdateStoneApplicationStatusFromCppWithString(const char* statusUpdateMessage);
+  extern void UpdateStoneApplicationStatusFromCppWithSerializedMessage(const char* statusUpdateMessage);
+  extern void stone_console_error(const char*);
+  extern void stone_console_warning(const char*);
+  extern void stone_console_info(const char*);
+  extern void stone_console_trace(const char*);
+
+  // C++ methods accessible from JS
+  extern void EMSCRIPTEN_KEEPALIVE CreateWasmApplication(ViewportHandle cppViewportHandle);
+  extern void EMSCRIPTEN_KEEPALIVE SetStartupParameter(const char* keyc, const char* value);
+  
+
+#ifdef __cplusplus
+}
+#endif
+
+// these methods must be implemented in the custom app "mainWasm.cpp"
+extern OrthancStone::IStoneApplication* CreateUserApplication(OrthancStone::MessageBroker& broker);
+extern OrthancStone::WasmPlatformApplicationAdapter* CreateWasmApplicationAdapter(OrthancStone::MessageBroker& broker, OrthancStone::IStoneApplication* application);
+
+namespace OrthancStone {
+
+  // default Observer to trigger Viewport redraw when something changes in the Viewport
+  class ViewportContentChangedObserver : public IObserver
+  {
+  private:
+    // Flag to avoid flooding JavaScript with redundant Redraw requests
+    bool isScheduled_; 
+
+  public:
+    ViewportContentChangedObserver(MessageBroker& broker) :
+      IObserver(broker),
+      isScheduled_(false)
+    {
+    }
+
+    void Reset()
+    {
+      isScheduled_ = false;
+    }
+
+    void OnViewportChanged(const Deprecated::IViewport::ViewportChangedMessage& message)
+    {
+      if (!isScheduled_)
+      {
+        ScheduleWebViewportRedrawFromCpp((ViewportHandle)&message.GetOrigin());  // loosing constness when transmitted to Web
+        isScheduled_ = true;
+      }
+    }
+  };
+
+  // default status bar to log messages on the console/stdout
+  class StatusBar : public Deprecated::IStatusBar
+  {
+  public:
+    virtual void ClearMessage()
+    {
+    }
+
+    virtual void SetMessage(const std::string& message)
+    {
+      printf("%s\n", message.c_str());
+    }
+  };
+}