Add webkit to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 771 insertions, 0 deletions

diff --git a/webkit/pending/DragController.cpp b/webkit/pending/DragController.cpp
new file mode 100644
index 0000000..57ebd2a
--- /dev/null
+++ b/webkit/pending/DragController.cpp
@@ -0,0 +1,771 @@
+/*
+ * Copyright (C) 2007 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "DragController.h"
+
+#include "CSSStyleDeclaration.h"
+#include "Clipboard.h"
+#include "ClipboardAccessPolicy.h"
+#include "DocLoader.h"
+#include "Document.h"
+#include "DocumentFragment.h"
+#include "DragActions.h"
+#include "DragClient.h"
+#include "DragData.h"
+#include "Editor.h"
+#include "EditorClient.h"
+#include "Element.h"
+#include "EventHandler.h"
+#include "FloatRect.h"
+#include "Frame.h"
+#include "FrameLoader.h"
+#include "FrameView.h"
+#include "HTMLAnchorElement.h"
+#include "HTMLInputElement.h"
+#include "HTMLNames.h"
+#include "HitTestResult.h"
+#include "Image.h"
+#include "MoveSelectionCommand.h"
+#include "Node.h"
+#include "Page.h"
+#include "PluginInfoStore.h"
+#include "RenderFileUploadControl.h"
+#include "RenderImage.h"
+#include "ReplaceSelectionCommand.h"
+#include "ResourceRequest.h"
+#include "SelectionController.h"
+#include "Settings.h"
+#include "SystemTime.h"
+#include "Text.h"
+#include "markup.h"
+#include <wtf/RefPtr.h>
+
+namespace WebCore {
+
+static PlatformMouseEvent createMouseEvent(DragData* dragData)
+{
+    // FIXME: We should fake modifier keys here.
+    return PlatformMouseEvent(dragData->clientPosition(), dragData->globalPosition(),
+                              LeftButton, MouseEventMoved, 0, false, false, false, false, currentTime());
+
+}
+    
+DragController::DragController(Page* page, DragClient* client)
+    : m_page(page)
+    , m_client(client)
+    , m_document(0)
+    , m_dragInitiator(0)
+    , m_dragDestinationAction(DragDestinationActionNone)
+    , m_dragSourceAction(DragSourceActionNone)
+    , m_didInitiateDrag(false)
+    , m_isHandlingDrag(false)
+    , m_dragOperation(DragOperationNone)
+{
+}
+    
+DragController::~DragController()
+{   
+    m_client->dragControllerDestroyed();
+}
+    
+static PassRefPtr<DocumentFragment> documentFragmentFromDragData(DragData* dragData, RefPtr<Range> context,
+                                          bool allowPlainText, bool& chosePlainText)
+{
+    ASSERT(dragData);
+    chosePlainText = false;
+
+    Document* document = context->ownerDocument();
+    ASSERT(document);
+    if (document && dragData->containsCompatibleContent()) {
+        if (PassRefPtr<DocumentFragment> fragment = dragData->asFragment(document))
+            return fragment;
+
+        if (dragData->containsURL()) {
+            String title;
+            String url = dragData->asURL(&title);
+            if (!url.isEmpty()) {
+                ExceptionCode ec;
+                RefPtr<HTMLAnchorElement> anchor = static_cast<HTMLAnchorElement*>(document->createElement("a", ec).get());
+                anchor->setHref(url);
+                RefPtr<Node> anchorText = document->createTextNode(title);
+                anchor->appendChild(anchorText, ec);
+                RefPtr<DocumentFragment> fragment = document->createDocumentFragment();
+                fragment->appendChild(anchor, ec);
+                return fragment.get();
+            }
+        }
+    }
+    if (allowPlainText && dragData->containsPlainText()) {
+        chosePlainText = true;
+        return createFragmentFromText(context.get(), dragData->asPlainText()).get();
+    }
+    
+    return 0;
+}
+
+bool DragController::dragIsMove(SelectionController* selectionController, DragData* dragData) 
+{
+    return m_document == m_dragInitiator
+        && selectionController->isContentEditable()
+        && !isCopyKeyDown();
+}
+
+void DragController::cancelDrag()
+{
+    m_page->dragCaretController()->clear();
+}
+
+void DragController::dragEnded()
+{
+    m_dragInitiator = 0;
+    m_didInitiateDrag = false; 
+    m_page->dragCaretController()->clear(); 
+}    
+
+DragOperation DragController::dragEntered(DragData* dragData) 
+{
+    return dragEnteredOrUpdated(dragData);
+}
+    
+void DragController::dragExited(DragData* dragData) 
+{   
+    ASSERT(dragData);
+    Frame* mainFrame = m_page->mainFrame();
+    
+    if (RefPtr<FrameView> v = mainFrame->view()) {
+        ClipboardAccessPolicy policy = mainFrame->loader()->baseURL().isLocalFile() ? ClipboardReadable : ClipboardTypesReadable;
+        RefPtr<Clipboard> clipboard = dragData->createClipboard(policy);
+        clipboard->setSourceOperation(dragData->draggingSourceOperationMask());
+        mainFrame->eventHandler()->cancelDragAndDrop(createMouseEvent(dragData), clipboard.get());
+        clipboard->setAccessPolicy(ClipboardNumb);    // invalidate clipboard here for security
+    }
+
+    cancelDrag();
+    m_document = 0;
+}
+    
+DragOperation DragController::dragUpdated(DragData* dragData) 
+{
+    return dragEnteredOrUpdated(dragData);
+}
+    
+bool DragController::performDrag(DragData* dragData)
+{   
+    ASSERT(dragData);
+    m_document = m_page->mainFrame()->documentAtPoint(dragData->clientPosition());
+    if (m_isHandlingDrag) {
+        ASSERT(m_dragDestinationAction & DragDestinationActionDHTML);
+        m_client->willPerformDragDestinationAction(DragDestinationActionDHTML, dragData);
+        RefPtr<Frame> mainFrame = m_page->mainFrame();
+        if (mainFrame->view()) {
+            // Sending an event can result in the destruction of the view and part.
+            RefPtr<Clipboard> clipboard = dragData->createClipboard(ClipboardReadable);
+            clipboard->setSourceOperation(dragData->draggingSourceOperationMask());
+            mainFrame->eventHandler()->performDragAndDrop(createMouseEvent(dragData), clipboard.get());
+            clipboard->setAccessPolicy(ClipboardNumb);    // invalidate clipboard here for security
+        }
+        m_document = 0;
+        return true;
+    } 
+    
+    if ((m_dragDestinationAction & DragDestinationActionEdit) && concludeDrag(dragData, m_dragDestinationAction)) {
+        m_document = 0;
+        return true;
+    }
+    
+    m_document = 0;
+
+    if (operationForLoad(dragData) == DragOperationNone)
+        return false;
+
+    m_client->willPerformDragDestinationAction(DragDestinationActionLoad, dragData);
+    m_page->mainFrame()->loader()->load(ResourceRequest(dragData->asURL()));
+    return true;
+}
+    
+DragOperation DragController::dragEnteredOrUpdated(DragData* dragData)
+{
+    ASSERT(dragData);
+    IntPoint windowPoint = dragData->clientPosition();
+    
+    Document* newDraggingDoc = 0;
+    if (Frame* frame = m_page->mainFrame())
+        newDraggingDoc = frame->documentAtPoint(windowPoint);
+    if (m_document != newDraggingDoc) {
+        if (m_document)
+            cancelDrag();
+        m_document = newDraggingDoc;
+    }
+    
+    m_dragDestinationAction = m_client->actionMaskForDrag(dragData);
+    
+    DragOperation operation = DragOperationNone;
+    
+    if (m_dragDestinationAction == DragDestinationActionNone)
+        cancelDrag();
+    else {
+        operation = tryDocumentDrag(dragData, m_dragDestinationAction);
+        if (operation == DragOperationNone && (m_dragDestinationAction & DragDestinationActionLoad))
+            return operationForLoad(dragData);
+    }
+    
+    return operation;
+}
+
+static HTMLInputElement* asFileInput(Node* node)
+{
+    ASSERT(node);
+    
+    // The button for a FILE input is a sub element with no set input type
+    // In order to get around this problem we assume any non-FILE input element
+    // is this internal button, and try querying the shadow parent node.
+    if (node->hasTagName(HTMLNames::inputTag) && node->isShadowNode() && static_cast<HTMLInputElement*>(node)->inputType() != HTMLInputElement::FILE)
+      node = node->shadowParentNode();
+    
+    if (!node || !node->hasTagName(HTMLNames::inputTag))
+        return 0;
+    
+    HTMLInputElement* inputElem = static_cast<HTMLInputElement*>(node);
+    if (inputElem->inputType() == HTMLInputElement::FILE)
+        return inputElem;
+    
+    return 0;
+}
+    
+DragOperation DragController::tryDocumentDrag(DragData* dragData, DragDestinationAction actionMask)
+{
+    ASSERT(dragData);
+    
+    if (!m_document)
+        return DragOperationNone;
+    
+    DragOperation operation = DragOperationNone;
+    if (actionMask & DragDestinationActionDHTML)
+        operation = tryDHTMLDrag(dragData);
+    m_isHandlingDrag = operation != DragOperationNone; 
+
+    RefPtr<FrameView> frameView = m_document->view();
+    if (!frameView)
+        return operation;
+    
+    if ((actionMask & DragDestinationActionEdit) && !m_isHandlingDrag && canProcessDrag(dragData)) {
+        if (dragData->containsColor()) 
+            return DragOperationGeneric;
+        
+        IntPoint dragPos = dragData->clientPosition();
+        IntPoint point = frameView->windowToContents(dragPos);
+        Element* element = m_document->elementFromPoint(point.x(), point.y());
+        ASSERT(element);
+        Frame* innerFrame = element->document()->frame();
+        ASSERT(innerFrame);
+        if (!asFileInput(element)) {
+            Selection dragCaret;
+            if (Frame* frame = m_document->frame())
+                dragCaret = frame->visiblePositionForPoint(point);
+            m_page->dragCaretController()->setSelection(dragCaret);
+        }
+        
+        return dragIsMove(innerFrame->selectionController(), dragData) ? DragOperationMove : DragOperationCopy;
+    } 
+    
+    m_page->dragCaretController()->clear();
+    return operation;
+}
+
+DragSourceAction DragController::delegateDragSourceAction(const IntPoint& windowPoint)
+{  
+    m_dragSourceAction = m_client->dragSourceActionMaskForPoint(windowPoint);
+    return m_dragSourceAction;
+}
+    
+DragOperation DragController::operationForLoad(DragData* dragData)
+{
+    ASSERT(dragData);
+    Document* doc = 0;
+    doc = m_page->mainFrame()->documentAtPoint(dragData->clientPosition());
+    if (doc && (m_didInitiateDrag || doc->isPluginDocument() || (doc->frame() && doc->frame()->editor()->clientIsEditable())))
+        return DragOperationNone;
+    return dragOperation(dragData);
+}
+
+static bool setSelectionToDragCaret(Frame* frame, Selection& dragCaret, RefPtr<Range>& range, const IntPoint& point)
+{
+    frame->selectionController()->setSelection(dragCaret);
+    if (frame->selectionController()->isNone()) {
+        dragCaret = frame->visiblePositionForPoint(point);
+        frame->selectionController()->setSelection(dragCaret);
+        range = dragCaret.toRange();
+    }
+    return !frame->selectionController()->isNone() && frame->selectionController()->isContentEditable();
+}
+
+bool DragController::concludeDrag(DragData* dragData, DragDestinationAction actionMask)
+{
+    ASSERT(dragData);
+    ASSERT(!m_isHandlingDrag);
+    ASSERT(actionMask & DragDestinationActionEdit);
+    
+    if (!m_document)
+        return false;
+    
+    IntPoint point = m_document->view()->windowToContents(dragData->clientPosition());
+    Element* element =  m_document->elementFromPoint(point.x(), point.y());
+    ASSERT(element);
+    Frame* innerFrame = element->ownerDocument()->frame();
+    ASSERT(innerFrame);    
+
+    if (dragData->containsColor()) {
+        Color color = dragData->asColor();
+        if (!color.isValid())
+            return false;
+        if (!innerFrame)
+            return false;
+        RefPtr<Range> innerRange = innerFrame->selectionController()->toRange();
+        RefPtr<CSSStyleDeclaration> style = m_document->createCSSStyleDeclaration();
+        ExceptionCode ec;
+        style->setProperty("color", color.name(), ec);
+        if (!innerFrame->editor()->shouldApplyStyle(style.get(), innerRange.get()))
+            return false;
+        m_client->willPerformDragDestinationAction(DragDestinationActionEdit, dragData);
+        innerFrame->editor()->applyStyle(style.get(), EditActionSetColor);
+        return true;
+    }
+    
+    if (!m_page->dragController()->canProcessDrag(dragData)) {
+        m_page->dragCaretController()->clear();
+        return false;
+    }
+    
+    if (HTMLInputElement* fileInput = asFileInput(element)) {
+        if (!dragData->containsFiles())
+            return false;
+        
+        Vector<String> filenames;
+        dragData->asFilenames(filenames);
+        if (filenames.isEmpty())
+            return false;
+        
+        // Ugly.  For security none of the API's available to us to set the input value 
+        // on file inputs.  Even forcing a change in HTMLInputElement doesn't work as
+        // RenderFileUploadControl clears the file when doing updateFromElement()
+        RenderFileUploadControl* renderer = static_cast<RenderFileUploadControl*>(fileInput->renderer());
+        
+        if (!renderer)
+            return false;
+        
+        // Only take the first filename as <input type="file" /> can only accept one
+        renderer->receiveDroppedFile(filenames[0]);
+        return true;
+    }
+
+    Selection dragCaret(m_page->dragCaretController()->selection());
+    m_page->dragCaretController()->clear();
+    RefPtr<Range> range = dragCaret.toRange();
+    
+    // For range to be null a WebKit client must have done something bad while
+    // manually controlling drag behaviour
+    if (!range)  
+        return false;
+    DocLoader* loader = range->ownerDocument()->docLoader();
+    loader->setAllowStaleResources(true);
+    if (dragIsMove(innerFrame->selectionController(), dragData) || dragCaret.isContentRichlyEditable()) { 
+        bool chosePlainText = false;
+        RefPtr<DocumentFragment> fragment = documentFragmentFromDragData(dragData, range, true, chosePlainText);
+        if (!fragment || !innerFrame->editor()->shouldInsertFragment(fragment, range, EditorInsertActionDropped)) {
+            loader->setAllowStaleResources(false);
+            return false;
+        }
+        
+        m_client->willPerformDragDestinationAction(DragDestinationActionEdit, dragData);
+        if (dragIsMove(innerFrame->selectionController(), dragData)) {
+            bool smartMove = innerFrame->selectionGranularity() == WordGranularity 
+                          && innerFrame->editor()->smartInsertDeleteEnabled() 
+                          && dragData->canSmartReplace();
+            applyCommand(new MoveSelectionCommand(fragment, dragCaret.base(), smartMove));
+        } else {
+            if (setSelectionToDragCaret(innerFrame, dragCaret, range, point))
+                applyCommand(new ReplaceSelectionCommand(m_document, fragment, true, dragData->canSmartReplace(), chosePlainText)); 
+        }    
+    } else {
+        String text = dragData->asPlainText();
+        if (text.isEmpty() || !innerFrame->editor()->shouldInsertText(text, range.get(), EditorInsertActionDropped)) {
+            loader->setAllowStaleResources(false);
+            return false;
+        }
+        
+        m_client->willPerformDragDestinationAction(DragDestinationActionEdit, dragData);
+        if (setSelectionToDragCaret(innerFrame, dragCaret, range, point))
+            applyCommand(new ReplaceSelectionCommand(m_document, createFragmentFromText(range.get(), text), true, false, true)); 
+    }
+    loader->setAllowStaleResources(false);
+
+    return true;
+}
+    
+    
+bool DragController::canProcessDrag(DragData* dragData) 
+{
+    ASSERT(dragData);
+
+    if (!dragData->containsCompatibleContent())
+        return false;
+    
+    IntPoint point = m_page->mainFrame()->view()->windowToContents(dragData->clientPosition());
+    HitTestResult result = HitTestResult(point);
+    if (!m_page->mainFrame()->renderer())
+        return false;
+
+    result = m_page->mainFrame()->eventHandler()->hitTestResultAtPoint(point, true);
+    
+    if (!result.innerNonSharedNode()) 
+        return false;
+    
+    if (dragData->containsFiles() && asFileInput(result.innerNonSharedNode()))
+        return true;
+        
+    if (!result.innerNonSharedNode()->isContentEditable())
+        return false;
+        
+    if (m_didInitiateDrag && m_document == m_dragInitiator && result.isSelected())
+        return false;
+
+    return true;
+}
+
+DragOperation DragController::tryDHTMLDrag(DragData* dragData)
+{   
+    ASSERT(dragData);
+    ASSERT(m_document);
+    DragOperation op = DragOperationNone;
+    RefPtr<Frame> frame = m_page->mainFrame();
+    RefPtr<FrameView> viewProtector = frame->view();
+    if (!viewProtector)
+        return DragOperationNone;
+    
+    ClipboardAccessPolicy policy = frame->loader()->baseURL().isLocalFile() ? ClipboardReadable : ClipboardTypesReadable;
+    RefPtr<Clipboard> clipboard = dragData->createClipboard(policy);
+    DragOperation srcOp = dragData->draggingSourceOperationMask();
+    clipboard->setSourceOperation(srcOp);
+    
+    PlatformMouseEvent event = createMouseEvent(dragData);
+    if (frame->eventHandler()->updateDragAndDrop(event, clipboard.get())) {
+        // *op unchanged if no source op was set
+        if (!clipboard->destinationOperation(op)) {
+            // The element accepted but they didn't pick an operation, so we pick one for them
+            // (as does WinIE).
+            if (srcOp & DragOperationCopy)
+                op = DragOperationCopy;
+            else if (srcOp & DragOperationMove || srcOp & DragOperationGeneric)
+                op = DragOperationMove;
+            else if (srcOp & DragOperationLink)
+                op = DragOperationLink;
+            else
+                op = DragOperationGeneric;
+        } else if (!(op & srcOp)) {
+            op = DragOperationNone;
+        }
+
+        clipboard->setAccessPolicy(ClipboardNumb);    // invalidate clipboard here for security
+        return op;
+    }
+    return op;
+}
+
+bool DragController::mayStartDragAtEventLocation(const Frame* frame, const IntPoint& framePos)
+{
+    ASSERT(frame);
+    ASSERT(frame->settings());
+
+    if (!frame->view() || !frame->renderer())
+        return false;
+
+    HitTestResult mouseDownTarget = HitTestResult(framePos);
+
+    mouseDownTarget = frame->eventHandler()->hitTestResultAtPoint(framePos, true);
+
+    if (mouseDownTarget.image() 
+        && !mouseDownTarget.absoluteImageURL().isEmpty()
+        && frame->settings()->loadsImagesAutomatically()
+        && m_dragSourceAction & DragSourceActionImage)
+        return true;
+
+    if (!mouseDownTarget.absoluteLinkURL().isEmpty()
+        && m_dragSourceAction & DragSourceActionLink
+        && mouseDownTarget.isLiveLink())
+        return true;
+
+    if (mouseDownTarget.isSelected()
+        && m_dragSourceAction & DragSourceActionSelection)
+        return true;
+
+    return false;
+
+}
+    
+static CachedImage* getCachedImage(Element* element)
+{
+    ASSERT(element);
+    RenderObject* renderer = element->renderer();
+    if (!renderer || !renderer->isImage()) 
+        return 0;
+    RenderImage* image = static_cast<RenderImage*>(renderer);
+    return image->cachedImage();
+}
+    
+static Image* getImage(Element* element)
+{
+    ASSERT(element);
+    RenderObject* renderer = element->renderer();
+    if (!renderer || !renderer->isImage()) 
+        return 0;
+    
+    RenderImage* image = static_cast<RenderImage*>(renderer);
+    if (image->cachedImage() && !image->cachedImage()->errorOccurred())
+        return image->cachedImage()->image();
+    return 0;
+}
+    
+static void prepareClipboardForImageDrag(Frame* src, Clipboard* clipboard, Element* node, const KURL& linkURL, const KURL& imageURL, const String& label)
+{
+    RefPtr<Range> range = src->document()->createRange();
+    ExceptionCode ec = 0;
+    range->selectNode(node, ec);
+    ASSERT(ec == 0);
+    src->selectionController()->setSelection(Selection(range.get(), DOWNSTREAM));           
+    clipboard->declareAndWriteDragImage(node, !linkURL.isEmpty() ? linkURL : imageURL, label, src);
+}
+    
+static IntPoint dragLocForDHTMLDrag(const IntPoint& mouseDraggedPoint, const IntPoint& dragOrigin, const IntPoint& dragImageOffset, bool isLinkImage)
+{
+    // dragImageOffset is the cursor position relative to the lower-left corner of the image.
+#if PLATFORM(MAC) 
+    // We add in the Y dimension because we are a flipped view, so adding moves the image down. 
+    const int yOffset = dragImageOffset.y();
+#else
+    const int yOffset = -dragImageOffset.y();
+#endif
+    
+    if (isLinkImage)
+        return IntPoint(mouseDraggedPoint.x() - dragImageOffset.x(), mouseDraggedPoint.y() + yOffset);
+    
+    return IntPoint(dragOrigin.x() - dragImageOffset.x(), dragOrigin.y() + yOffset);
+}
+    
+static IntPoint dragLocForSelectionDrag(Frame* src)
+{
+    IntRect draggingRect = enclosingIntRect(src->selectionRect());
+    int xpos = draggingRect.right();
+    xpos = draggingRect.x() < xpos ? draggingRect.x() : xpos;
+    int ypos = draggingRect.bottom();
+#if PLATFORM(MAC)
+    // Deal with flipped coordinates on Mac
+    ypos = draggingRect.y() > ypos ? draggingRect.y() : ypos;
+#else
+    ypos = draggingRect.y() < ypos ? draggingRect.y() : ypos;
+#endif
+    return IntPoint(xpos, ypos);
+}
+    
+bool DragController::startDrag(Frame* src, Clipboard* clipboard, DragOperation srcOp, const PlatformMouseEvent& dragEvent, const IntPoint& dragOrigin, bool isDHTMLDrag)
+{    
+    ASSERT(src);
+    ASSERT(clipboard);
+    
+    if (!src->view() || !src->renderer())
+        return false;
+    
+    HitTestResult dragSource = HitTestResult(dragOrigin);
+    dragSource = src->eventHandler()->hitTestResultAtPoint(dragOrigin, true);
+    KURL linkURL = dragSource.absoluteLinkURL();
+    KURL imageURL = dragSource.absoluteImageURL();
+    bool isSelected = dragSource.isSelected();
+    
+    IntPoint mouseDraggedPoint = src->view()->windowToContents(dragEvent.pos());
+    
+    m_draggingImageURL = KURL();
+    m_dragOperation = srcOp;
+    
+    DragImageRef dragImage = 0;
+    IntPoint dragLoc(0, 0);
+    IntPoint dragImageOffset(0, 0);
+    
+    if (isDHTMLDrag) 
+        dragImage = clipboard->createDragImage(dragImageOffset);
+    
+    // We allow DHTML/JS to set the drag image, even if its a link, image or text we're dragging.
+    // This is in the spirit of the IE API, which allows overriding of pasteboard data and DragOp.
+    if (dragImage) {
+        dragLoc = dragLocForDHTMLDrag(mouseDraggedPoint, dragOrigin, dragImageOffset, !linkURL.isEmpty());
+        m_dragOffset = dragImageOffset;
+    }
+    
+    bool startedDrag = true; // optimism - we almost always manage to start the drag
+    
+    Node* node = dragSource.innerNonSharedNode();
+    
+    if (!imageURL.isEmpty() && node && node->isElementNode()
+            && getImage(static_cast<Element*>(node)) 
+            && (m_dragSourceAction & DragSourceActionImage)) {
+        Element* element = static_cast<Element*>(node);
+        if (!clipboard->hasData()) {
+            m_draggingImageURL = imageURL; 
+            prepareClipboardForImageDrag(src, clipboard, element, linkURL, imageURL, dragSource.altDisplayString());
+        }
+        
+        m_client->willPerformDragSourceAction(DragSourceActionImage, dragOrigin, clipboard);
+        
+        if (!dragImage) {
+            IntRect imageRect = dragSource.imageRect();
+            imageRect.setLocation(m_page->mainFrame()->view()->windowToContents(src->view()->contentsToWindow(imageRect.location())));
+            doImageDrag(element, dragOrigin, dragSource.imageRect(), clipboard, src, m_dragOffset);
+        } else 
+            // DHTML defined drag image
+            doSystemDrag(dragImage, dragLoc, dragOrigin, clipboard, src, false);
+
+    } else if (!linkURL.isEmpty() && (m_dragSourceAction & DragSourceActionLink)) {
+        if (!clipboard->hasData())
+            // Simplify whitespace so the title put on the clipboard resembles what the user sees
+            // on the web page. This includes replacing newlines with spaces.
+            clipboard->writeURL(linkURL, dragSource.textContent().simplifyWhiteSpace(), src);
+        
+        m_client->willPerformDragSourceAction(DragSourceActionLink, dragOrigin, clipboard);
+        if (!dragImage) {
+            dragImage = m_client->createDragImageForLink(linkURL, dragSource.textContent(), src);
+            IntSize size = dragImageSize(dragImage);
+            m_dragOffset = IntPoint(-size.width() / 2, -LinkDragBorderInset);
+            dragLoc = IntPoint(mouseDraggedPoint.x() + m_dragOffset.x(), mouseDraggedPoint.y() + m_dragOffset.y());
+        } 
+        doSystemDrag(dragImage, dragLoc, mouseDraggedPoint, clipboard, src, true);
+    } else if (isSelected && (m_dragSourceAction & DragSourceActionSelection)) {
+        RefPtr<Range> selectionRange = src->selectionController()->toRange();
+        ASSERT(selectionRange);
+        if (!clipboard->hasData()) 
+            clipboard->writeRange(selectionRange.get(), src);
+        m_client->willPerformDragSourceAction(DragSourceActionSelection, dragOrigin, clipboard);
+        if (!dragImage) {
+            dragImage = createDragImageForSelection(src);
+            dragLoc = dragLocForSelectionDrag(src);
+            m_dragOffset = IntPoint((int)(dragOrigin.x() - dragLoc.x()), (int)(dragOrigin.y() - dragLoc.y()));
+        }
+        doSystemDrag(dragImage, dragLoc, dragOrigin, clipboard, src, false);
+    } else if (isDHTMLDrag) {
+        ASSERT(m_dragSourceAction & DragSourceActionDHTML);
+        m_client->willPerformDragSourceAction(DragSourceActionDHTML, dragOrigin, clipboard);
+        doSystemDrag(dragImage, dragLoc, dragOrigin, clipboard, src, false);
+    } else {
+        // Only way I know to get here is if to get here is if the original element clicked on in the mousedown is no longer
+        // under the mousedown point, so linkURL, imageURL and isSelected are all false/empty.
+        startedDrag = false;
+    }
+    
+    if (dragImage)
+        deleteDragImage(dragImage);
+    return startedDrag;
+}
+    
+void DragController::doImageDrag(Element* element, const IntPoint& dragOrigin, const IntRect& rect, Clipboard* clipboard, Frame* frame, IntPoint& dragImageOffset)
+{
+    IntPoint mouseDownPoint = dragOrigin;
+    DragImageRef dragImage;
+    IntPoint origin;
+    
+    Image* image = getImage(element);
+    if (image && image->size().height() * image->size().width() <= MaxOriginalImageArea
+        && (dragImage = createDragImageFromImage(image))) {
+        IntSize originalSize = rect.size();
+        origin = rect.location();
+        
+        dragImage = fitDragImageToMaxSize(dragImage, rect.size(), maxDragImageSize());
+        dragImage = dissolveDragImageToFraction(dragImage, DragImageAlpha);
+        IntSize newSize = dragImageSize(dragImage);
+        
+        // Properly orient the drag image and orient it differently if it's smaller than the original
+        float scale = newSize.width() / (float)originalSize.width();
+        float dx = origin.x() - mouseDownPoint.x();
+        dx *= scale;
+        origin.setX((int)(dx + 0.5));
+#if PLATFORM(MAC)
+        //Compensate for accursed flipped coordinates in cocoa
+        origin.setY(origin.y() + originalSize.height());
+#endif
+        float dy = origin.y() - mouseDownPoint.y();
+        dy *= scale;
+        origin.setY((int)(dy + 0.5));
+    } else {
+        dragImage = createDragImageIconForCachedImage(getCachedImage(element));
+        if (dragImage)
+            origin = IntPoint(DragIconRightInset - dragImageSize(dragImage).width(), DragIconBottomInset);
+    }
+    
+    dragImageOffset.setX(mouseDownPoint.x() + origin.x());
+    dragImageOffset.setY(mouseDownPoint.y() + origin.y());
+    doSystemDrag(dragImage, dragImageOffset, dragOrigin, clipboard, frame, false);
+    
+    deleteDragImage(dragImage);
+}
+    
+void DragController::doSystemDrag(DragImageRef image, const IntPoint& dragLoc, const IntPoint& eventPos, Clipboard* clipboard, Frame* frame, bool forLink)
+{
+    m_didInitiateDrag = true;
+    m_dragInitiator = frame->document();
+    // Protect this frame and view, as a load may occur mid drag and attempt to unload this frame
+    RefPtr<Frame> frameProtector = m_page->mainFrame();
+    RefPtr<FrameView> viewProtector = frameProtector->view();
+    m_client->startDrag(image, viewProtector->windowToContents(frame->view()->contentsToWindow(dragLoc)),
+        viewProtector->windowToContents(frame->view()->contentsToWindow(eventPos)), clipboard, frameProtector.get(), forLink);
+    
+    // Drag has ended, dragEnded *should* have been called, however it is possible  
+    // for the UIDelegate to take over the drag, and fail to send the appropriate
+    // drag termination event.  As dragEnded just resets drag variables, we just 
+    // call it anyway to be on the safe side
+    // Except if drag and drop happens asynchronously, in which case dragging
+    // has not ended.
+    //dragEnded();
+}
+    
+// Manual drag caret manipulation
+void DragController::placeDragCaret(const IntPoint& windowPoint)
+{
+    Frame* mainFrame = m_page->mainFrame();    
+    Document* newDraggingDoc = mainFrame->documentAtPoint(windowPoint);
+    if (m_document != newDraggingDoc) {
+        if (m_document)
+            cancelDrag();
+        m_document = newDraggingDoc;
+    }
+    if (!m_document)
+        return;
+    Frame* frame = m_document->frame();
+    ASSERT(frame);
+    FrameView* frameView = frame->view();
+    if (!frameView)
+        return;
+    IntPoint framePoint = frameView->windowToContents(windowPoint);
+    Selection dragCaret(frame->visiblePositionForPoint(framePoint));  
+    m_page->dragCaretController()->setSelection(dragCaret);
+}
+    
+}