/*
 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
 * Copyright (C) 2009 Apple Inc. All rights reserved.
 *
 * 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 LayoutSVGTextPath_h
#define LayoutSVGTextPath_h

#include "core/layout/svg/LayoutSVGInline.h"

namespace blink {

// This class maps a 1D location in the "path space"; [0, path length] to a
// (2D) point on the path and provides the normal (angle from the x-axis) for
// said point.
class PathPositionMapper {
    USING_FAST_MALLOC(PathPositionMapper);
public:
    static PassOwnPtr<PathPositionMapper> create(const Path& path)
    {
        return adoptPtr(new PathPositionMapper(path));
    }

    enum PositionType {
        OnPath,
        BeforePath,
        AfterPath,
    };
    PositionType pointAndNormalAtLength(float length, FloatPoint&, float& angle);
    float length() const { return m_pathLength; }

private:
    explicit PathPositionMapper(const Path&);

    Path::PositionCalculator m_positionCalculator;
    float m_pathLength;
};

class LayoutSVGTextPath final : public LayoutSVGInline {
public:
    explicit LayoutSVGTextPath(Element*);

    PassOwnPtr<PathPositionMapper> layoutPath() const;
    float calculateStartOffset(float) const;

    bool isChildAllowed(LayoutObject*, const ComputedStyle&) const override;

    bool isOfType(LayoutObjectType type) const override { return type == LayoutObjectSVGTextPath || LayoutSVGInline::isOfType(type); }

    const char* name() const override { return "LayoutSVGTextPath"; }
};

DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutSVGTextPath, isSVGTextPath());

} // namespace blink

#endif // LayoutSVGTextPath_h