/*
* Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies)
* Copyright (C) 2009 Antonio Gomes <tonikitoo@webkit.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef SpatialNavigation_h
#define SpatialNavigation_h
#include "core/dom/Node.h"
#include "core/html/HTMLFrameOwnerElement.h"
#include "core/page/FocusType.h"
#include "platform/geometry/LayoutRect.h"
#include <limits>
namespace WebCore {
class Element;
class LocalFrame;
class HTMLAreaElement;
class IntRect;
class RenderObject;
inline long long maxDistance()
{
return std::numeric_limits<long long>::max();
}
inline int fudgeFactor()
{
return 2;
}
bool isSpatialNavigationEnabled(const LocalFrame*);
// Spatially speaking, two given elements in a web page can be:
// 1) Fully aligned: There is a full intersection between the rects, either
// vertically or horizontally.
//
// * Horizontally * Vertically
// _
// |_| _ _ _ _ _ _
// |_|...... _ |_|_|_|_|_|_|
// |_| |_| . .
// |_|......|_| OR . .
// |_| |_| . .
// |_|......|_| _ _ _ _
// |_| |_|_|_|_|
//
//
// 2) Partially aligned: There is a partial intersection between the rects, either
// vertically or horizontally.
//
// * Horizontally * Vertically
// _ _ _ _ _ _
// |_| |_|_|_|_|_|
// |_|.... _ OR . .
// |_| |_| . .
// |_|....|_| ._._ _
// |_| |_|_|_|
// |_|
//
// 3) Or, otherwise, not aligned at all.
//
// * Horizontally * Vertically
// _ _ _ _ _
// |_| |_|_|_|_|
// |_| .
// |_| .
// . OR .
// _ . ._ _ _ _ _
// |_| |_|_|_|_|_|
// |_|
// |_|
//
// "Totally Aligned" elements are preferable candidates to move
// focus to over "Partially Aligned" ones, that on its turns are
// more preferable than "Not Aligned".
enum RectsAlignment {
None = 0,
Partial,
Full
};
struct FocusCandidate {
FocusCandidate()
: visibleNode(0)
, focusableNode(0)
, enclosingScrollableBox(0)
, distance(maxDistance())
, parentDistance(maxDistance())
, alignment(None)
, parentAlignment(None)
, isOffscreen(true)
, isOffscreenAfterScrolling(true)
{
}
FocusCandidate(Node*, FocusType);
explicit FocusCandidate(HTMLAreaElement*, FocusType);
bool isNull() const { return !visibleNode; }
bool inScrollableContainer() const { return visibleNode && enclosingScrollableBox; }
bool isFrameOwnerElement() const { return visibleNode && visibleNode->isFrameOwnerElement(); }
Document* document() const { return visibleNode ? &visibleNode->document() : 0; }
// We handle differently visibleNode and FocusableNode to properly handle the areas of imagemaps,
// where visibleNode would represent the image element and focusableNode would represent the area element.
// In all other cases, visibleNode and focusableNode are one and the same.
Node* visibleNode;
Node* focusableNode;
Node* enclosingScrollableBox;
long long distance;
long long parentDistance;
RectsAlignment alignment;
RectsAlignment parentAlignment;
LayoutRect rect;
bool isOffscreen;
bool isOffscreenAfterScrolling;
};
bool hasOffscreenRect(Node*, FocusType = FocusTypeNone);
bool scrollInDirection(LocalFrame*, FocusType);
bool scrollInDirection(Node* container, FocusType);
bool canScrollInDirection(const Node* container, FocusType);
bool canScrollInDirection(const LocalFrame*, FocusType);
bool canBeScrolledIntoView(FocusType, const FocusCandidate&);
bool areElementsOnSameLine(const FocusCandidate& firstCandidate, const FocusCandidate& secondCandidate);
void distanceDataForNode(FocusType, const FocusCandidate& current, FocusCandidate&);
Node* scrollableEnclosingBoxOrParentFrameForNodeInDirection(FocusType, Node*);
LayoutRect nodeRectInAbsoluteCoordinates(Node*, bool ignoreBorder = false);
LayoutRect frameRectInAbsoluteCoordinates(LocalFrame*);
LayoutRect virtualRectForDirection(FocusType, const LayoutRect& startingRect, LayoutUnit width = 0);
LayoutRect virtualRectForAreaElementAndDirection(HTMLAreaElement&, FocusType);
HTMLFrameOwnerElement* frameOwnerElement(FocusCandidate&);
} // namspace WebCore
#endif // SpatialNavigation_h