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/*
* Copyright (C) 2004, 2008 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
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* 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.
*/
#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_EDITING_VISIBLE_POSITION_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_EDITING_VISIBLE_POSITION_H_
#include <iosfwd>
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/editing/position_with_affinity.h"
#include "third_party/blink/renderer/core/editing/text_affinity.h"
#include "third_party/blink/renderer/platform/heap/handle.h"
namespace blink {
// |VisiblePosition| is an immutable object representing "canonical position"
// with affinity.
//
// "canonical position" is roughly equivalent to a position where we can place
// caret, see |canonicalPosition()| for actual definition.
//
// "affinity" represents a place of caret at wrapped line. UPSTREAM affinity
// means caret is placed at end of line. DOWNSTREAM affinity means caret is
// placed at start of line.
//
// Example of affinity:
// abc^def where "^" represent |Position|
// When above text line wrapped after "abc"
// abc| UPSTREAM |VisiblePosition|
// |def DOWNSTREAM |VisiblePosition|
//
// NOTE: UPSTREAM affinity will be used only if pos is at end of a wrapped line,
// otherwise it will be converted to DOWNSTREAM.
template <typename Strategy>
class VisiblePositionTemplate final {
DISALLOW_NEW();
public:
VisiblePositionTemplate();
// Node: Other than |createVisiblePosition()| and
// |createVisiblePositionDeprecated()|, we should not use |create()|.
static VisiblePositionTemplate Create(
const PositionWithAffinityTemplate<Strategy>&);
// Intentionally delete |operator==()| and |operator!=()| for reducing
// compilation error message.
// TODO(yosin) We'll have |equals()| when we have use cases of checking
// equality of both position and affinity.
bool operator==(const VisiblePositionTemplate&) const = delete;
bool operator!=(const VisiblePositionTemplate&) const = delete;
bool IsValid() const;
bool IsValidFor(const Document&) const;
// TODO(editing-dev): We should have |DCHECK(isValid())| in the following
// functions. However, there are some clients storing a VisiblePosition and
// inspecting its properties after mutation. This should be fixed.
// See crbug.com/648949 for details.
bool IsNull() const { return position_with_affinity_.IsNull(); }
bool IsNotNull() const { return position_with_affinity_.IsNotNull(); }
bool IsOrphan() const { return DeepEquivalent().IsOrphan(); }
PositionTemplate<Strategy> DeepEquivalent() const {
return position_with_affinity_.GetPosition();
}
PositionTemplate<Strategy> ToParentAnchoredPosition() const {
return DeepEquivalent().ParentAnchoredEquivalent();
}
PositionWithAffinityTemplate<Strategy> ToPositionWithAffinity() const {
return position_with_affinity_;
}
TextAffinity Affinity() const { return position_with_affinity_.Affinity(); }
static VisiblePositionTemplate<Strategy> AfterNode(const Node&);
static VisiblePositionTemplate<Strategy> BeforeNode(const Node&);
static VisiblePositionTemplate<Strategy> FirstPositionInNode(const Node&);
static VisiblePositionTemplate<Strategy> InParentAfterNode(const Node&);
static VisiblePositionTemplate<Strategy> InParentBeforeNode(const Node&);
static VisiblePositionTemplate<Strategy> LastPositionInNode(const Node&);
void Trace(blink::Visitor*);
#ifndef NDEBUG
void ShowTreeForThis() const;
#endif
private:
explicit VisiblePositionTemplate(
const PositionWithAffinityTemplate<Strategy>&);
PositionWithAffinityTemplate<Strategy> position_with_affinity_;
#if DCHECK_IS_ON()
uint64_t dom_tree_version_;
uint64_t style_version_;
#endif
};
extern template class CORE_EXTERN_TEMPLATE_EXPORT
VisiblePositionTemplate<EditingStrategy>;
extern template class CORE_EXTERN_TEMPLATE_EXPORT
VisiblePositionTemplate<EditingInFlatTreeStrategy>;
using VisiblePosition = VisiblePositionTemplate<EditingStrategy>;
using VisiblePositionInFlatTree =
VisiblePositionTemplate<EditingInFlatTreeStrategy>;
CORE_EXPORT VisiblePosition
CreateVisiblePosition(const Position&, TextAffinity = TextAffinity::kDefault);
CORE_EXPORT VisiblePosition CreateVisiblePosition(const PositionWithAffinity&);
CORE_EXPORT VisiblePositionInFlatTree
CreateVisiblePosition(const PositionInFlatTree&,
TextAffinity = TextAffinity::kDefault);
CORE_EXPORT VisiblePositionInFlatTree
CreateVisiblePosition(const PositionInFlatTreeWithAffinity&);
CORE_EXPORT std::ostream& operator<<(std::ostream&, const VisiblePosition&);
CORE_EXPORT std::ostream& operator<<(std::ostream&,
const VisiblePositionInFlatTree&);
} // namespace blink
#ifndef NDEBUG
// Outside the WebCore namespace for ease of invocation from gdb.
void showTree(const blink::VisiblePosition*);
void showTree(const blink::VisiblePosition&);
#endif
#endif // THIRD_PARTY_BLINK_RENDERER_CORE_EDITING_VISIBLE_POSITION_H_