/*

 * Copyright (C) 2004 Apple Computer, 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. 

 */

#ifndef VisibleSelection_h

#define VisibleSelection_h

#include "TextGranularity.h"

#include "VisiblePosition.h"

namespace WebCore {

class Position;

const EAffinity SEL_DEFAULT_AFFINITY = DOWNSTREAM;

class VisibleSelection {

public:

    enum SelectionType { NoSelection, CaretSelection, RangeSelection };

    VisibleSelection();

    VisibleSelection(const Position&, EAffinity);

    VisibleSelection(const Position&, const Position&, EAffinity = SEL_DEFAULT_AFFINITY);

    VisibleSelection(const Range*, EAffinity = SEL_DEFAULT_AFFINITY);

    VisibleSelection(const VisiblePosition&);

    VisibleSelection(const VisiblePosition&, const VisiblePosition&);

    static VisibleSelection selectionFromContentsOfNode(Node*);

    SelectionType selectionType() const { return m_selectionType; }

    void setAffinity(EAffinity affinity) { m_affinity = affinity; }

    EAffinity affinity() const { return m_affinity; }

    void setBase(const Position&);

    void setBase(const VisiblePosition&);

    void setExtent(const Position&);

    void setExtent(const VisiblePosition&);

    Position base() const { return m_base; }

    Position extent() const { return m_extent; }

    Position start() const { return m_start; }

    Position end() const { return m_end; }

    VisiblePosition visibleStart() const { return VisiblePosition(m_start, isRange() ? DOWNSTREAM : affinity()); }

    VisiblePosition visibleEnd() const { return VisiblePosition(m_end, isRange() ? UPSTREAM : affinity()); }

    bool isNone() const { return selectionType() == NoSelection; }

    bool isCaret() const { return selectionType() == CaretSelection; }

    bool isRange() const { return selectionType() == RangeSelection; }

    bool isCaretOrRange() const { return selectionType() != NoSelection; }

    bool isBaseFirst() const { return m_baseIsFirst; }

    bool isAll(StayInEditableContent) const;

    void appendTrailingWhitespace();

    bool expandUsingGranularity(TextGranularity granularity);

    // We don't yet support multi-range selections, so we only ever have one range to return.

    PassRefPtr<Range> firstRange() const;

    // FIXME: Most callers probably don't want this function, but are using it

    // for historical reasons.  toNormalizedRange contracts the range around

    // text, and moves the caret upstream before returning the range.

    PassRefPtr<Range> toNormalizedRange() const;

    Element* rootEditableElement() const;

    bool isContentEditable() const;

    bool isContentRichlyEditable() const;

    Node* shadowTreeRootNode() const;

    void debugPosition() const;

#ifndef NDEBUG

    void formatForDebugger(char* buffer, unsigned length) const;

    void showTreeForThis() const;

#endif

    void setWithoutValidation(const Position&, const Position&);

private:

    void validate(TextGranularity = CharacterGranularity);

    // Support methods for validate()

    void setBaseAndExtentToDeepEquivalents();

    void setStartAndEndFromBaseAndExtentRespectingGranularity(TextGranularity);

    void adjustSelectionToAvoidCrossingEditingBoundaries();

    void updateSelectionType();

    // We need to store these as Positions because VisibleSelection is

    // used to store values in editing commands for use when

    // undoing the command. We need to be able to create a selection that, while currently

    // invalid, will be valid once the changes are undone.

    Position m_base;   // Where the first click happened

    Position m_extent; // Where the end click happened

    Position m_start;  // Leftmost position when expanded to respect granularity

    Position m_end;    // Rightmost position when expanded to respect granularity

    EAffinity m_affinity;           // the upstream/downstream affinity of the caret

    // these are cached, can be recalculated by validate()

    SelectionType m_selectionType;    // None, Caret, Range

    bool m_baseIsFirst;               // true if base is before the extent

};

inline bool operator==(const VisibleSelection& a, const VisibleSelection& b)

{

    return a.start() == b.start() && a.end() == b.end() && a.affinity() == b.affinity() && a.isBaseFirst() == b.isBaseFirst();

}

inline bool operator!=(const VisibleSelection& a, const VisibleSelection& b)

{

    return !(a == b);

}

} // namespace WebCore

#ifndef NDEBUG

// Outside the WebCore namespace for ease of invocation from gdb.

void showTree(const WebCore::VisibleSelection&);

void showTree(const WebCore::VisibleSelection*);

#endif

#endif // VisibleSelection_h