1 files changed, 232 insertions, 0 deletions

diff --git a/libraries/ecore/src/lib/ecore_win32/ecore_win32_dnd_drop_target.cpp b/libraries/ecore/src/lib/ecore_win32/ecore_win32_dnd_drop_target.cpp
new file mode 100644
index 0000000..e19fb5d
--- /dev/null
+++ b/libraries/ecore/src/lib/ecore_win32/ecore_win32_dnd_drop_target.cpp
@@ -0,0 +1,232 @@
+/*
+ * vim:ts=8:sw=3:sts=8:noexpandtab:cino=>5n-3f0^-2{2
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "ecore_win32_dnd_drop_target.h"
+
+#include "ecore_win32_private.h"
+
+
+// structors
+
+DropTarget::DropTarget(HWND window, Ecore_Win32_Dnd_DropTarget_Callback callback, void *window_obj_ptr)
+  : ref_count_(1)
+  , window_(window)
+  , allow_drop_(false)
+  , drop_callback_(callback)
+  ,drop_callback_ptr_(window_obj_ptr)
+{ }
+
+
+// IUnknown
+
+HRESULT DropTarget::QueryInterface(REFIID iid, void **ppvObject)
+{
+   // check to see what interface has been requested
+   if (iid == IID_IDropTarget || iid == IID_IUnknown)
+   {
+      AddRef();
+      *ppvObject = this;
+      return S_OK;
+   }
+   *ppvObject = 0;
+
+   return E_NOINTERFACE;
+}
+
+ULONG DropTarget::AddRef()
+{
+   return InterlockedIncrement(&ref_count_);
+}
+
+ULONG DropTarget::Release()
+{
+   LONG count = InterlockedDecrement(&ref_count_);
+   if (count == 0)
+   {
+      delete this;
+      return 0;
+   }
+
+   return count;
+}
+
+
+// IDropTarget
+
+HRESULT DropTarget::DragEnter(IDataObject *pDataObject, DWORD grfKeyState, POINTL pt, DWORD *pdwEffect)
+{
+   // does the dataobject contain data we want?
+   allow_drop_ = QueryDataObject(pDataObject) &&
+      (drop_callback_ == NULL ||
+      (drop_callback_(drop_callback_ptr_, ECORE_WIN32_DND_EVENT_DRAG_ENTER, pt.x, pt.y, NULL, 0) != 0));
+
+   if (allow_drop_)
+   {
+      // get the dropeffect based on keyboard state
+      *pdwEffect = DropEffect(grfKeyState, pt, *pdwEffect);
+      SetFocus(window_);
+      //PositionCursor(_hwnd, pt);
+   }
+   else
+      *pdwEffect = DROPEFFECT_NONE;
+   return S_OK;
+}
+
+HRESULT DropTarget::DragOver(DWORD grfKeyState, POINTL pt, DWORD * pdwEffect)
+{
+   allow_drop_ =
+     (drop_callback_ == NULL) ||
+     (drop_callback_(drop_callback_ptr_, ECORE_WIN32_DND_EVENT_DRAG_OVER, pt.x, pt.y, NULL, 0) != 0);
+
+   if (allow_drop_)
+   {
+      *pdwEffect = DropEffect(grfKeyState, pt, *pdwEffect);
+      //PositionCursor(m_hWnd, pt);
+   }
+   else
+   {
+      *pdwEffect = DROPEFFECT_NONE;
+   }
+
+   return S_OK;
+}
+
+HRESULT DropTarget::DragLeave()
+{
+   POINT pt;
+
+   GetCursorPos(&pt);
+   if (drop_callback_ != NULL)
+     drop_callback_(drop_callback_ptr_, ECORE_WIN32_DND_EVENT_DRAG_LEAVE, pt.x, pt.y, NULL, 0);
+
+   return S_OK;
+}
+
+HRESULT DropTarget::Drop(IDataObject *pDataObject, DWORD grfKeyState, POINTL pt, DWORD *pdwEffect)
+{
+   if (allow_drop_)
+   {
+      // construct a FORMATETC object
+      FORMATETC fmtetc = { CF_TEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
+      STGMEDIUM stgmed;
+
+      // See if the dataobject contains any TEXT stored as a HGLOBAL
+      if (pDataObject->QueryGetData(&fmtetc) == S_OK)
+      {
+         // Yippie! the data is there, so go get it!
+         if (pDataObject->GetData(&fmtetc, &stgmed) == S_OK)
+         {
+            // we asked for the data as a HGLOBAL, so access it appropriately
+            PVOID data = GlobalLock(stgmed.hGlobal);
+            UINT size = GlobalSize(stgmed.hGlobal);
+
+            if (drop_callback_ != NULL)
+            {
+               drop_callback_(drop_callback_ptr_,
+                              ECORE_WIN32_DND_EVENT_DROP,
+                              pt.x, pt.y,
+                              data, size);
+            }
+
+            GlobalUnlock(stgmed.hGlobal);
+
+            // release the data using the COM API
+            ReleaseStgMedium(&stgmed);
+         }
+      }
+      *pdwEffect = DropEffect(grfKeyState, pt, *pdwEffect);
+   }
+   else
+   {
+      *pdwEffect = DROPEFFECT_NONE;
+   }
+
+   return S_OK;
+}
+
+
+// internal helper function
+
+DWORD DropTarget::DropEffect(DWORD grfKeyState, POINTL pt __UNUSED__, DWORD dwAllowed)
+{
+   DWORD dwEffect = 0;
+
+   // 1. check "pt" -> do we allow a drop at the specified coordinates?
+
+   // 2. work out that the drop-effect should be based on grfKeyState
+   if (grfKeyState & MK_CONTROL)
+   {
+           dwEffect = dwAllowed & DROPEFFECT_COPY;
+   }
+   else if (grfKeyState & MK_SHIFT)
+   {
+           dwEffect = dwAllowed & DROPEFFECT_MOVE;
+   }
+
+   // 3. no key-modifiers were specified (or drop effect not allowed), so
+   //    base the effect on those allowed by the dropsource
+   if (dwEffect == 0)
+   {
+           if (dwAllowed & DROPEFFECT_COPY) dwEffect = DROPEFFECT_COPY;
+           if (dwAllowed & DROPEFFECT_MOVE) dwEffect = DROPEFFECT_MOVE;
+   }
+
+   return dwEffect;
+}
+
+bool DropTarget::QueryDataObject(IDataObject *pDataObject)
+{
+    FORMATETC fmtetc = { CF_TEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
+
+    // does the data object support CF_TEXT using a HGLOBAL?
+    return pDataObject->QueryGetData(&fmtetc) == S_OK;
+}
+
+
+// ecore_win32 private functions
+
+void *_ecore_win32_dnd_register_drop_window(HWND hwnd,  Ecore_Win32_Dnd_DropTarget_Callback callback, void *ptr)
+{
+   DropTarget *pDropTarget = new DropTarget(hwnd, callback, ptr);
+
+   if (pDropTarget == NULL)
+     return NULL;
+
+   // acquire a strong lock
+   if (FAILED(CoLockObjectExternal(pDropTarget, TRUE, FALSE)))
+     {
+        delete pDropTarget;
+        return NULL;
+     }
+
+   // tell OLE that the window is a drop target
+   if (FAILED(RegisterDragDrop(hwnd, pDropTarget)))
+     {
+        delete pDropTarget;
+        return NULL;
+     }
+
+   return pDropTarget;
+}
+
+void _ecore_win32_dnd_unregister_drop_window(HWND hwnd, void *drop_target)
+{
+   IDropTarget *pDropTarget = (IDropTarget *)drop_target;
+
+   if (drop_target == NULL)
+     return;
+
+   // remove drag+drop
+   RevokeDragDrop(hwnd);
+
+   // remove the strong lock
+   CoLockObjectExternal(pDropTarget, FALSE, TRUE);
+
+   // release our own reference
+   pDropTarget->Release();
+}