michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include <stdio.h>
michael@0: #include "nsIDragService.h"
michael@0: #include "nsWidgetsCID.h"
michael@0: #include "nsNativeDragTarget.h"
michael@0: #include "nsDragService.h"
michael@0: #include "nsIServiceManager.h"
michael@0: #include "nsIDOMNode.h"
michael@0: #include "nsCOMPtr.h"
michael@0: 
michael@0: #include "nsIWidget.h"
michael@0: #include "nsWindow.h"
michael@0: #include "nsClipboard.h"
michael@0: #include "KeyboardLayout.h"
michael@0: 
michael@0: #include "mozilla/MouseEvents.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: using namespace mozilla::widget;
michael@0: 
michael@0: /* Define Interface IDs */
michael@0: static NS_DEFINE_IID(kIDragServiceIID, NS_IDRAGSERVICE_IID);
michael@0: 
michael@0: // This is cached for Leave notification
michael@0: static POINTL gDragLastPoint;
michael@0: 
michael@0: /*
michael@0:  * class nsNativeDragTarget
michael@0:  */
michael@0: nsNativeDragTarget::nsNativeDragTarget(nsIWidget * aWidget)
michael@0:   : m_cRef(0), 
michael@0:     mEffectsAllowed(DROPEFFECT_MOVE | DROPEFFECT_COPY | DROPEFFECT_LINK),
michael@0:     mEffectsPreferred(DROPEFFECT_NONE),
michael@0:     mTookOwnRef(false), mWidget(aWidget), mDropTargetHelper(nullptr)
michael@0: {
michael@0:   static NS_DEFINE_IID(kCDragServiceCID,  NS_DRAGSERVICE_CID);
michael@0: 
michael@0:   mHWnd = (HWND)mWidget->GetNativeData(NS_NATIVE_WINDOW);
michael@0: 
michael@0:   /*
michael@0:    * Create/Get the DragService that we have implemented
michael@0:    */
michael@0:   CallGetService(kCDragServiceCID, &mDragService);
michael@0: }
michael@0: 
michael@0: nsNativeDragTarget::~nsNativeDragTarget()
michael@0: {
michael@0:   NS_RELEASE(mDragService);
michael@0: 
michael@0:   if (mDropTargetHelper) {
michael@0:     mDropTargetHelper->Release();
michael@0:     mDropTargetHelper = nullptr;
michael@0:   }
michael@0: }
michael@0: 
michael@0: // IUnknown methods - see iunknown.h for documentation
michael@0: STDMETHODIMP
michael@0: nsNativeDragTarget::QueryInterface(REFIID riid, void** ppv)
michael@0: {
michael@0:   *ppv=nullptr;
michael@0: 
michael@0:   if (IID_IUnknown == riid || IID_IDropTarget == riid)
michael@0:     *ppv=this;
michael@0: 
michael@0:   if (nullptr!=*ppv) {
michael@0:     ((LPUNKNOWN)*ppv)->AddRef();
michael@0:     return S_OK;
michael@0:   }
michael@0: 
michael@0:   return E_NOINTERFACE;
michael@0: }
michael@0: 
michael@0: STDMETHODIMP_(ULONG)
michael@0: nsNativeDragTarget::AddRef(void)
michael@0: {
michael@0:   ++m_cRef;
michael@0:   NS_LOG_ADDREF(this, m_cRef, "nsNativeDragTarget", sizeof(*this));
michael@0:   return m_cRef;
michael@0: }
michael@0: 
michael@0: STDMETHODIMP_(ULONG) nsNativeDragTarget::Release(void)
michael@0: {
michael@0:   --m_cRef;
michael@0:   NS_LOG_RELEASE(this, m_cRef, "nsNativeDragTarget");
michael@0:   if (0 != m_cRef)
michael@0:     return m_cRef;
michael@0: 
michael@0:   delete this;
michael@0:   return 0;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsNativeDragTarget::GetGeckoDragAction(DWORD grfKeyState, LPDWORD pdwEffect,
michael@0:                                        uint32_t * aGeckoAction)
michael@0: {
michael@0:   // If a window is disabled or a modal window is on top of it
michael@0:   // (which implies it is disabled), then we should not allow dropping.
michael@0:   if (!mWidget->IsEnabled()) {
michael@0:     *pdwEffect = DROPEFFECT_NONE;
michael@0:     *aGeckoAction = nsIDragService::DRAGDROP_ACTION_NONE;
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // If the user explicitly uses a modifier key, they want the associated action
michael@0:   // Shift + Control -> LINK, Shift -> MOVE, Ctrl -> COPY
michael@0:   DWORD desiredEffect = DROPEFFECT_NONE;
michael@0:   if ((grfKeyState & MK_CONTROL) && (grfKeyState & MK_SHIFT)) {
michael@0:     desiredEffect = DROPEFFECT_LINK;
michael@0:   } else if (grfKeyState & MK_SHIFT) {
michael@0:     desiredEffect = DROPEFFECT_MOVE;
michael@0:   } else if (grfKeyState & MK_CONTROL) {
michael@0:     desiredEffect = DROPEFFECT_COPY;
michael@0:   }
michael@0: 
michael@0:   // Determine the desired effect from what is allowed and preferred.
michael@0:   if (!(desiredEffect &= mEffectsAllowed)) {
michael@0:     // No modifier key effect is set which is also allowed, check
michael@0:     // the preference of the data.
michael@0:     desiredEffect = mEffectsPreferred & mEffectsAllowed;
michael@0:     if (!desiredEffect) {
michael@0:       // No preference is set, so just fall back to the allowed effect itself
michael@0:       desiredEffect = mEffectsAllowed;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Otherwise we should specify the first available effect 
michael@0:   // from MOVE, COPY, or LINK.
michael@0:   if (desiredEffect & DROPEFFECT_MOVE) {
michael@0:     *pdwEffect = DROPEFFECT_MOVE;
michael@0:     *aGeckoAction = nsIDragService::DRAGDROP_ACTION_MOVE;
michael@0:   } else if (desiredEffect & DROPEFFECT_COPY) {
michael@0:     *pdwEffect = DROPEFFECT_COPY;
michael@0:     *aGeckoAction = nsIDragService::DRAGDROP_ACTION_COPY;
michael@0:   } else if (desiredEffect & DROPEFFECT_LINK) {
michael@0:     *pdwEffect = DROPEFFECT_LINK;
michael@0:     *aGeckoAction = nsIDragService::DRAGDROP_ACTION_LINK;
michael@0:   } else {
michael@0:     *pdwEffect = DROPEFFECT_NONE;
michael@0:     *aGeckoAction = nsIDragService::DRAGDROP_ACTION_NONE;
michael@0:   } 
michael@0: }
michael@0: 
michael@0: inline
michael@0: bool
michael@0: IsKeyDown(char key)
michael@0: {
michael@0:   return GetKeyState(key) < 0;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsNativeDragTarget::DispatchDragDropEvent(uint32_t aEventType, POINTL aPT)
michael@0: {
michael@0:   nsEventStatus status;
michael@0:   WidgetDragEvent event(true, aEventType, mWidget);
michael@0: 
michael@0:   nsWindow * win = static_cast<nsWindow *>(mWidget);
michael@0:   win->InitEvent(event);
michael@0:   POINT cpos;
michael@0: 
michael@0:   cpos.x = aPT.x;
michael@0:   cpos.y = aPT.y;
michael@0: 
michael@0:   if (mHWnd != nullptr) {
michael@0:     ::ScreenToClient(mHWnd, &cpos);
michael@0:     event.refPoint.x = cpos.x;
michael@0:     event.refPoint.y = cpos.y;
michael@0:   } else {
michael@0:     event.refPoint.x = 0;
michael@0:     event.refPoint.y = 0;
michael@0:   }
michael@0: 
michael@0:   ModifierKeyState modifierKeyState;
michael@0:   modifierKeyState.InitInputEvent(event);
michael@0: 
michael@0:   event.inputSource = static_cast<nsBaseDragService*>(mDragService)->GetInputSource();
michael@0: 
michael@0:   mWidget->DispatchEvent(&event, status);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsNativeDragTarget::ProcessDrag(uint32_t     aEventType,
michael@0:                                 DWORD        grfKeyState,
michael@0:                                 POINTL       ptl,
michael@0:                                 DWORD*       pdwEffect)
michael@0: {
michael@0:   // Before dispatching the event make sure we have the correct drop action set
michael@0:   uint32_t geckoAction;
michael@0:   GetGeckoDragAction(grfKeyState, pdwEffect, &geckoAction);
michael@0: 
michael@0:   // Set the current action into the Gecko specific type
michael@0:   nsCOMPtr<nsIDragSession> currSession;
michael@0:   mDragService->GetCurrentSession(getter_AddRefs(currSession));
michael@0:   if (!currSession) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   currSession->SetDragAction(geckoAction);
michael@0: 
michael@0:   // Dispatch the event into Gecko
michael@0:   DispatchDragDropEvent(aEventType, ptl);
michael@0: 
michael@0:   if (aEventType != NS_DRAGDROP_DROP) {
michael@0:     // Get the cached drag effect from the drag service, the data member should
michael@0:     // have been set by whoever handled the WidgetGUIEvent or nsIDOMEvent on
michael@0:     // drags.
michael@0:     bool canDrop;
michael@0:     currSession->GetCanDrop(&canDrop);
michael@0:     if (!canDrop) {
michael@0:       *pdwEffect = DROPEFFECT_NONE;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Clear the cached value
michael@0:   currSession->SetCanDrop(false);
michael@0: }
michael@0: 
michael@0: // IDropTarget methods
michael@0: STDMETHODIMP
michael@0: nsNativeDragTarget::DragEnter(LPDATAOBJECT pIDataSource,
michael@0:                               DWORD        grfKeyState,
michael@0:                               POINTL       ptl,
michael@0:                               DWORD*       pdwEffect)
michael@0: {
michael@0:   if (!mDragService) {
michael@0:     return E_FAIL;
michael@0:   }
michael@0: 
michael@0:   mEffectsAllowed = *pdwEffect;
michael@0:   AddLinkSupportIfCanBeGenerated(pIDataSource);
michael@0: 
michael@0:   // Drag and drop image helper
michael@0:   if (GetDropTargetHelper()) {
michael@0:     POINT pt = { ptl.x, ptl.y };
michael@0:     GetDropTargetHelper()->DragEnter(mHWnd, pIDataSource, &pt, *pdwEffect);
michael@0:   }
michael@0: 
michael@0:   // save a ref to this, in case the window is destroyed underneath us
michael@0:   NS_ASSERTION(!mTookOwnRef, "own ref already taken!");
michael@0:   this->AddRef();
michael@0:   mTookOwnRef = true;
michael@0: 
michael@0:   // tell the drag service about this drag (it may have come from an
michael@0:   // outside app).
michael@0:   mDragService->StartDragSession();
michael@0: 
michael@0:   void* tempOutData = nullptr;
michael@0:   uint32_t tempDataLen = 0;
michael@0:   nsresult loadResult = nsClipboard::GetNativeDataOffClipboard(
michael@0:       pIDataSource, 0, ::RegisterClipboardFormat(CFSTR_PREFERREDDROPEFFECT), nullptr, &tempOutData, &tempDataLen);
michael@0:   if (NS_SUCCEEDED(loadResult) && tempOutData) {
michael@0:     mEffectsPreferred = *((DWORD*)tempOutData);
michael@0:     nsMemory::Free(tempOutData);
michael@0:   } else {
michael@0:     // We have no preference if we can't obtain it
michael@0:     mEffectsPreferred = DROPEFFECT_NONE;
michael@0:   }
michael@0: 
michael@0:   // Set the native data object into drag service
michael@0:   //
michael@0:   // This cast is ok because in the constructor we created a
michael@0:   // the actual implementation we wanted, so we know this is
michael@0:   // a nsDragService. It should be a private interface, though.
michael@0:   nsDragService * winDragService =
michael@0:     static_cast<nsDragService *>(mDragService);
michael@0:   winDragService->SetIDataObject(pIDataSource);
michael@0: 
michael@0:   // Now process the native drag state and then dispatch the event
michael@0:   ProcessDrag(NS_DRAGDROP_ENTER, grfKeyState, ptl, pdwEffect);
michael@0: 
michael@0:   return S_OK;
michael@0: }
michael@0: 
michael@0: void 
michael@0: nsNativeDragTarget::AddLinkSupportIfCanBeGenerated(LPDATAOBJECT aIDataSource) 
michael@0: {
michael@0:   // If we don't have a link effect, but we can generate one, fix the 
michael@0:   // drop effect to include it.
michael@0:   if (!(mEffectsAllowed & DROPEFFECT_LINK) && aIDataSource) {
michael@0:     if (S_OK == ::OleQueryLinkFromData(aIDataSource)) {
michael@0:       mEffectsAllowed |= DROPEFFECT_LINK;
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: STDMETHODIMP
michael@0: nsNativeDragTarget::DragOver(DWORD   grfKeyState,
michael@0:                              POINTL  ptl,
michael@0:                              LPDWORD pdwEffect)
michael@0: {
michael@0:   if (!mDragService) {
michael@0:     return E_FAIL;
michael@0:   }
michael@0: 
michael@0:   // If a LINK effect could be generated previously from a DragEnter(),
michael@0:   // then we should include it as an allowed effect.
michael@0:   mEffectsAllowed = (*pdwEffect) | (mEffectsAllowed & DROPEFFECT_LINK);
michael@0: 
michael@0:   nsCOMPtr<nsIDragSession> currentDragSession;
michael@0:   mDragService->GetCurrentSession(getter_AddRefs(currentDragSession));
michael@0:   if (!currentDragSession) {
michael@0:     return S_OK;  // Drag was canceled.
michael@0:   }
michael@0: 
michael@0:   // without the AddRef() |this| can get destroyed in an event handler
michael@0:   this->AddRef();
michael@0: 
michael@0:   // Drag and drop image helper
michael@0:   if (GetDropTargetHelper()) {
michael@0:     POINT pt = { ptl.x, ptl.y };
michael@0:     GetDropTargetHelper()->DragOver(&pt, *pdwEffect);
michael@0:   }
michael@0: 
michael@0:   mDragService->FireDragEventAtSource(NS_DRAGDROP_DRAG);
michael@0:   // Now process the native drag state and then dispatch the event
michael@0:   ProcessDrag(NS_DRAGDROP_OVER, grfKeyState, ptl, pdwEffect);
michael@0: 
michael@0:   this->Release();
michael@0: 
michael@0:   return S_OK;
michael@0: }
michael@0: 
michael@0: STDMETHODIMP
michael@0: nsNativeDragTarget::DragLeave()
michael@0: {
michael@0:   if (!mDragService) {
michael@0:     return E_FAIL;
michael@0:   }
michael@0: 
michael@0:   // Drag and drop image helper
michael@0:   if (GetDropTargetHelper()) {
michael@0:     GetDropTargetHelper()->DragLeave();
michael@0:   }
michael@0: 
michael@0:   // dispatch the event into Gecko
michael@0:   DispatchDragDropEvent(NS_DRAGDROP_EXIT, gDragLastPoint);
michael@0: 
michael@0:   nsCOMPtr<nsIDragSession> currentDragSession;
michael@0:   mDragService->GetCurrentSession(getter_AddRefs(currentDragSession));
michael@0: 
michael@0:   if (currentDragSession) {
michael@0:     nsCOMPtr<nsIDOMNode> sourceNode;
michael@0:     currentDragSession->GetSourceNode(getter_AddRefs(sourceNode));
michael@0: 
michael@0:     if (!sourceNode) {
michael@0:       // We're leaving a window while doing a drag that was
michael@0:       // initiated in a different app. End the drag session, since
michael@0:       // we're done with it for now (until the user drags back into
michael@0:       // mozilla).
michael@0:       mDragService->EndDragSession(false);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // release the ref that was taken in DragEnter
michael@0:   NS_ASSERTION(mTookOwnRef, "want to release own ref, but not taken!");
michael@0:   if (mTookOwnRef) {
michael@0:     this->Release();
michael@0:     mTookOwnRef = false;
michael@0:   }
michael@0: 
michael@0:   return S_OK;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsNativeDragTarget::DragCancel()
michael@0: {
michael@0:   // Cancel the drag session if we did DragEnter.
michael@0:   if (mTookOwnRef) {
michael@0:     if (GetDropTargetHelper()) {
michael@0:       GetDropTargetHelper()->DragLeave();
michael@0:     }
michael@0:     if (mDragService) {
michael@0:       mDragService->EndDragSession(false);
michael@0:     }
michael@0:     this->Release(); // matching the AddRef in DragEnter
michael@0:     mTookOwnRef = false;
michael@0:   }
michael@0: }
michael@0: 
michael@0: STDMETHODIMP
michael@0: nsNativeDragTarget::Drop(LPDATAOBJECT pData,
michael@0:                          DWORD        grfKeyState,
michael@0:                          POINTL       aPT,
michael@0:                          LPDWORD      pdwEffect)
michael@0: {
michael@0:   if (!mDragService) {
michael@0:     return E_FAIL;
michael@0:   }
michael@0: 
michael@0:   mEffectsAllowed = *pdwEffect;
michael@0:   AddLinkSupportIfCanBeGenerated(pData);
michael@0: 
michael@0:   // Drag and drop image helper
michael@0:   if (GetDropTargetHelper()) {
michael@0:     POINT pt = { aPT.x, aPT.y };
michael@0:     GetDropTargetHelper()->Drop(pData, &pt, *pdwEffect);
michael@0:   }
michael@0: 
michael@0:   // Set the native data object into the drag service
michael@0:   //
michael@0:   // This cast is ok because in the constructor we created a
michael@0:   // the actual implementation we wanted, so we know this is
michael@0:   // a nsDragService (but it should still be a private interface)
michael@0:   nsDragService* winDragService = static_cast<nsDragService*>(mDragService);
michael@0:   winDragService->SetIDataObject(pData);
michael@0: 
michael@0:   // NOTE: ProcessDrag spins the event loop which may destroy arbitrary objects.
michael@0:   // We use strong refs to prevent it from destroying these:
michael@0:   nsRefPtr<nsNativeDragTarget> kungFuDeathGrip = this;
michael@0:   nsCOMPtr<nsIDragService> serv = mDragService;
michael@0: 
michael@0:   // Now process the native drag state and then dispatch the event
michael@0:   ProcessDrag(NS_DRAGDROP_DROP, grfKeyState, aPT, pdwEffect);
michael@0: 
michael@0:   nsCOMPtr<nsIDragSession> currentDragSession;
michael@0:   serv->GetCurrentSession(getter_AddRefs(currentDragSession));
michael@0:   if (!currentDragSession) {
michael@0:     return S_OK;  // DragCancel() was called.
michael@0:   }
michael@0: 
michael@0:   // Let the win drag service know whether this session experienced 
michael@0:   // a drop event within the application. Drop will not oocur if the
michael@0:   // drop landed outside the app. (used in tab tear off, bug 455884)
michael@0:   winDragService->SetDroppedLocal();
michael@0: 
michael@0:   // tell the drag service we're done with the session
michael@0:   // Use GetMessagePos to get the position of the mouse at the last message
michael@0:   // seen by the event loop. (Bug 489729)
michael@0:   DWORD pos = ::GetMessagePos();
michael@0:   POINT cpos;
michael@0:   cpos.x = GET_X_LPARAM(pos);
michael@0:   cpos.y = GET_Y_LPARAM(pos);
michael@0:   winDragService->SetDragEndPoint(nsIntPoint(cpos.x, cpos.y));
michael@0:   serv->EndDragSession(true);
michael@0: 
michael@0:   // release the ref that was taken in DragEnter
michael@0:   NS_ASSERTION(mTookOwnRef, "want to release own ref, but not taken!");
michael@0:   if (mTookOwnRef) {
michael@0:     this->Release();
michael@0:     mTookOwnRef = false;
michael@0:   }
michael@0: 
michael@0:   return S_OK;
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * By lazy loading mDropTargetHelper we save 50-70ms of startup time
michael@0:  * which is ~5% of startup time.
michael@0: */
michael@0: IDropTargetHelper*
michael@0: nsNativeDragTarget::GetDropTargetHelper()
michael@0: {
michael@0:   if (!mDropTargetHelper) { 
michael@0:     CoCreateInstance(CLSID_DragDropHelper, nullptr, CLSCTX_INPROC_SERVER,
michael@0:                      IID_IDropTargetHelper, (LPVOID*)&mDropTargetHelper);
michael@0:   }
michael@0: 
michael@0:   return mDropTargetHelper;
michael@0: }