Outlook add-in integrating Skype

#ifndef IRibbonCallback_H
#define IRibbonCallback_H

    typedef enum RibbonElementType {
        RibbonElementType_Tab, 
        RibbonElementType_Group, 
        RibbonElementType_Button, 
        RibbonElementType_Label, 
        //  add more element types as needed
    } RibbonElementType;

    typedef enum RibbonControlSize
    {
	    RibbonControlSize_Regular   = 0,
	    RibbonControlSize_Large     = 1
    } RibbonControlSize;

    //  IRibbonCallback DISPIDs
    #define DISPID_RIBBONCALLBACK_ONLOAD            (0x00000001)
    #define DISPID_RIBBONCALLBACK_ONGETVISIBLE      (0x00000002)
    #define DISPID_RIBBONCALLBACK_ONGETLABEL        (0x00000003)
    #define DISPID_RIBBONCALLBACK_ONGETSIZE         (0x00000004)
    #define DISPID_RIBBONCALLBACK_ONGETSCREENTIP    (0x00000005)
    #define DISPID_RIBBONCALLBACK_ONGETSUPERTIP     (0x00000006)
    #define DISPID_RIBBONCALLBACK_ONGETIMAGEMSO     (0x00000007)
    #define DISPID_RIBBONCALLBACK_ONGETIMAGE        (0x00000008)
    #define DISPID_RIBBONCALLBACK_ONGETENABLED      (0x00000009)
    #define DISPID_RIBBONCALLBACK_ONACTION          (0x0000000A)


    typedef struct IRibbonCallback IRibbonCallback;

    typedef struct IRibbonCallbackVtbl {
        HRESULT (NDAPI *QueryInterface)(
            IRibbonCallback     *This,
            REFIID              riid,
            void                **ppvObject
            );
        ULONG (NDAPI *AddRef)( 
            IRibbonCallback     *This
            );
        ULONG (NDAPI *Release)( 
            IRibbonCallback     *This
            );
        HRESULT (NDAPI *GetTypeInfoCount)( 
            IRibbonCallback     *This,
            UINT                *pctinfo
            );
        HRESULT (NDAPI *GetTypeInfo)( 
            IRibbonCallback     *This,
            UINT                iTInfo,
            LCID                lcid,
            ITypeInfo           **ppTInfo
            );
        HRESULT (NDAPI *GetIDsOfNames)( 
            IRibbonCallback     *This,
            REFIID              riid,
            LPOLESTR            *rgszNames,
            UINT                cNames,
            LCID                lcid,
            DISPID              *rgDispId
            );
        HRESULT (NDAPI *Invoke)( 
            IRibbonCallback     *This,
            DISPID              dispIdMember,
            REFIID              riid,
            LCID                lcid,
            WORD                wFlags,
            DISPPARAMS          *pDispParams,
            VARIANT             *pVarResult,
            EXCEPINFO           *pExcepInfo,
            UINT                *puArgErr
            );
        HRESULT (NDAPI *OnLoad)(
            IRibbonCallback     *This, 
            IDispatch           *RibbonUI
            );
        HRESULT (NDAPI *OnAction)(
            IRibbonCallback     *This,
            IDispatch           *RibbonControl
            );
	    HRESULT (NDAPI *OnGetVisible)(
            IRibbonCallback     *This,
		    IDispatch           *RibbonControl, 
		    VARIANT_BOOL        *Visible
            );
	    HRESULT (NDAPI *OnGetLabel)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    BSTR                *Label
            );
	    HRESULT (NDAPI *OnGetSize)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    RibbonControlSize   *Size
            );
	    HRESULT (NDAPI *OnGetScreentip)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    BSTR                *Screentip
            );
	    HRESULT (NDAPI *OnGetSupertip)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    BSTR                *Supertip
            );
	    HRESULT (NDAPI *OnGetImageMso)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    BSTR                *ImageMso
            );
	    HRESULT (NDAPI *OnGetImage)(
            IRibbonCallback     *This,
		    IDispatch           *Control, 
		    IPictureDisp        **PictureDisp
            );
	    HRESULT (NDAPI *OnGetEnabled)(
            IRibbonCallback     *This,
		    IDispatch           *RibbonControl, 
		    VARIANT_BOOL        *Enabled
            );

    } IRibbonCallbackVtbl;

    typedef struct IRibbonCallback
    {
        const struct IRibbonCallbackVtbl *lpVtbl;
    } IRibbonCallback;

    const IID*
    IRibbonCallback_GetIID(
        VOID
    );


    //  macros
    #define RibbonCallback_QueryInterface(This, riid, ppv) \
        ((((This)->lpVtbl)->QueryInterface)((This), (riid), (ppv)))
    #define RibbonCallback_AddRef(This) \
        ((((This)->lpVtbl)->AddRef)(This))
    #define RibbonCallback_Release(This) \
        ((((This)->lpVtbl)->Release)(This))
    #define RibbonCallback_GetTypeInfoCount(This, pctinfo) \
        ((((This)->lpVtbl)->GetTypeInfoCount)((This), (pctinfo)))
    #define RibbonCallback_GetTypeInfo(This, iTInfo, lcid, ppTInfo) \
        ((((This)->lpVtbl)->GetTypeInfo)((This), (iTInfo), (lcid), (pctinfo)))
    #define RibbonCallback_GetIDsOfNames(This, riid, rgszNames, cNames, lcid, rgDispId) \
        ((((This)->lpVtbl)->GetIDsOfNames)((This), (riid), (rgszNames), (cNames), (lcid), (rgDispId)))
    #define RibbonCallback_Invoke(This, dispIdMember, riid, lcid, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr) \
        ((((This)->lpVtbl)->Invoke)((This), (riid), (lcid), (wFlags), (pDispParams), (pVarResult), (pExcepInfo), (puArgErr)))

    #define RibbonCallback_OnLoad(This, RibbonUI) \
        ((((This)->lpVtbl)->OnLoad)((This), (RibbonUI)))
    #define RibbonCallback_OnAction(This, RibbonControl) \
        ((((This)->lpVtbl)->OnAction)((This), (RibbonControl)))
    #define RibbonCallback_OnGetVisible(This, RibbonControl, Visible) \
        ((((This)->lpVtbl)->OnGetVisible)((This), (RibbonControl), (Visible)))
    #define RibbonCallback_OnGetLabel(This, RibbonControl, Label) \
        ((((This)->lpVtbl)->OnGetLabel)((This), (RibbonControl), (Label)))
    #define RibbonCallback_OnGetSize(This, RibbonControl, Size) \
        ((((This)->lpVtbl)->OnGetSize)((This), (RibbonControl), (Size)))
    #define RibbonCallback_OnGetScreentip(This, RibbonControl, Screentip) \
        ((((This)->lpVtbl)->OnGetScreentip)((This), (RibbonControl), (Screentip)))
    #define RibbonCallback_OnGetSupertip(This, RibbonControl, Supertip) \
        ((((This)->lpVtbl)->OnGetSupertip)((This), (RibbonControl), (Supertip)))
    #define RibbonCallback_OnGetImageMso(This, RibbonControl, ImageMso) \
        ((((This)->lpVtbl)->OnGetImageMso)((This), (RibbonControl), (ImageMso)))
    #define RibbonCallback_OnGetImage(This, RibbonControl, Image) \
        ((((This)->lpVtbl)->OnGetImage)((This), (RibbonControl), (Image)))
    #define RibbonCallback_OnGetEnabled(This, RibbonControl, Enabled) \
        ((((This)->lpVtbl)->OnGetEnabled)((This), (RibbonControl), (Enabled)))

#endif  //  IRibbonCallback_H