/*

 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.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 SVGCharacterLayoutInfo_h

#define SVGCharacterLayoutInfo_h

#if ENABLE(SVG)

#include "Path.h"

#include <wtf/Assertions.h>

#include <wtf/Vector.h>

namespace WebCore {

class InlineFlowBox;

class SVGElement;

class SVGLengthList;

class SVGNumberList;

class SVGTextPositioningElement;

template<class Type>

class PositionedVector : public Vector<Type> {

public:

    PositionedVector<Type>()

        : m_position(0)

    {

    }

    unsigned position() const

    {

        return m_position;

    }

    void advance(unsigned position)

    {

        m_position += position;

        ASSERT(m_position < Vector<Type>::size());

    }

    Type valueAtCurrentPosition() const

    {

        ASSERT(m_position < Vector<Type>::size());

        return Vector<Type>::at(m_position);

    }

private:

    unsigned m_position;

};

class PositionedFloatVector : public PositionedVector<float> { };

struct SVGChar;

struct SVGCharacterLayoutInfo {

    SVGCharacterLayoutInfo();

    enum StackType { XStack, YStack, DxStack, DyStack, AngleStack, BaselineShiftStack };

    bool xValueAvailable() const;

    bool yValueAvailable() const;

    bool dxValueAvailable() const;

    bool dyValueAvailable() const;

    bool angleValueAvailable() const;

    bool baselineShiftValueAvailable() const;

    float xValueNext() const;

    float yValueNext() const;

    float dxValueNext() const;

    float dyValueNext() const;

    float angleValueNext() const;

    float baselineShiftValueNext() const;

    void processedChunk(float savedShiftX, float savedShiftY);

    void processedSingleCharacter();

    bool nextPathLayoutPointAndAngle(float glyphAdvance, float extraAdvance, float newOffset);

    // Used for text-on-path.

    void addLayoutInformation(InlineFlowBox*, float textAnchorOffset = 0.0f);

    bool inPathLayout() const;

    void setInPathLayout(bool value);

    // Used for anything else.

    void addLayoutInformation(SVGTextPositioningElement*);

    // Global position

    float curx;

    float cury;

    // Global rotation

    float angle;

    // Accumulated dx/dy values

    float dx;

    float dy;

    // Accumulated baseline-shift values

    float shiftx;

    float shifty;

    // Path specific advance values to handle lengthAdjust

    float pathExtraAdvance;

    float pathTextLength;

    float pathChunkLength;

    // Result vector

    Vector<SVGChar> svgChars;

    bool nextDrawnSeperated : 1;

private:

    // Used for baseline-shift.

    void addStackContent(StackType, float);

    // Used for angle.

    void addStackContent(StackType, SVGNumberList*);

    // Used for x/y/dx/dy.    

    void addStackContent(StackType, SVGLengthList*, const SVGElement*);

    void addStackContent(StackType, const PositionedFloatVector&);

    void xStackWalk();

    void yStackWalk();

    void dxStackWalk();

    void dyStackWalk();

    void angleStackWalk();

    void baselineShiftStackWalk();

    bool isInitialLayout() const;

private:

    bool xStackChanged : 1;

    bool yStackChanged : 1;

    bool dxStackChanged : 1;

    bool dyStackChanged : 1;

    bool angleStackChanged : 1;

    bool baselineShiftStackChanged : 1;

    // text on path layout

    bool pathLayout : 1;

    float currentOffset;

    float startOffset;

    float layoutPathLength;

    Path layoutPath;

    Vector<PositionedFloatVector> xStack;

    Vector<PositionedFloatVector> yStack;

    Vector<PositionedFloatVector> dxStack;

    Vector<PositionedFloatVector> dyStack;

    Vector<PositionedFloatVector> angleStack;

    Vector<float> baselineShiftStack;

};

} // namespace WebCore

#endif // ENABLE(SVG)

#endif // SVGCharacterLayoutInfo_h