// ole32.c - Win32 COM / OLE stubs
// No COM infrastructure at this stage; all functions fail gracefully.
#include <stdint.h>
#include <stddef.h>

// ---------------------------------------------------------------------------
// Types
// ---------------------------------------------------------------------------
typedef long   HRESULT;
typedef void*  IUnknown;

#define S_OK              ((HRESULT)0x00000000L)
#define E_NOTIMPL         ((HRESULT)0x80004001L)
#define E_OUTOFMEMORY     ((HRESULT)0x8007000EL)
#define COINIT_MULTITHREADED 0x0

// GUID - 16-byte COM interface identifier.
typedef struct {
    unsigned int   Data1;
    unsigned short Data2;
    unsigned short Data3;
    unsigned char  Data4[8];
} GUID;

// PROPVARIANT - variant type used by shell / media APIs.
typedef struct {
    unsigned short vt;
    unsigned short wReserved1, wReserved2, wReserved3;
    union {
        long long     hVal;
        double        dblVal;
        void*         punkVal;
        unsigned char bVal;
        unsigned int  ulVal;
        // ... (only common fields; full union is ~16 bytes)
        unsigned char padding[16];
    };
} PROPVARIANT;

extern void SysFree(void* ptr, size_t size);

// ---------------------------------------------------------------------------
// COM initialisation
// ---------------------------------------------------------------------------
__declspec(dllexport) HRESULT CoInitializeEx(void* reserved, unsigned long coInit) {
    (void)reserved; (void)coInit;
    return S_OK; // Pretend success; no actual apartment is created.
}

__declspec(dllexport) void CoUninitialize(void) {
    // No-op.
}

// ---------------------------------------------------------------------------
// Object creation
// ---------------------------------------------------------------------------
__declspec(dllexport) HRESULT CoCreateInstance(const GUID* clsid, IUnknown* outer,
                                                unsigned long ctx, const GUID* iid,
                                                void** ppv) {
    (void)clsid; (void)outer; (void)ctx; (void)iid;
    if (ppv) *ppv = (void*)0;
    return E_NOTIMPL;
}

// ---------------------------------------------------------------------------
// Memory
// ---------------------------------------------------------------------------
__declspec(dllexport) void CoTaskMemFree(void* pv) {
    if (pv) SysFree(pv, 0);
}

// ---------------------------------------------------------------------------
// PROPVARIANT
// ---------------------------------------------------------------------------
__declspec(dllexport) HRESULT PropVariantClear(PROPVARIANT* pvar) {
    if (!pvar) return E_NOTIMPL;
    // Zero the entire structure; no deep release needed for stub types.
    unsigned char* p = (unsigned char*)pvar;
    for (size_t i = 0; i < sizeof(*pvar); i++) p[i] = 0;
    return S_OK;
}