/*
 * Copyright (C) Research In Motion Limited 2009-2010. 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 LayoutSVGResourcePaintServer_h
#define LayoutSVGResourcePaintServer_h

#include "core/layout/svg/LayoutSVGResourceContainer.h"
#include "platform/graphics/Color.h"
#include "platform/graphics/Gradient.h"
#include "platform/graphics/Pattern.h"
#include "wtf/Allocator.h"

class SkPaint;

namespace blink {

enum LayoutSVGResourceMode {
    ApplyToFillMode,
    ApplyToStrokeMode,
};

class LayoutObject;
class LayoutSVGResourcePaintServer;
class ComputedStyle;

class SVGPaintServer {
    STACK_ALLOCATED();
public:
    explicit SVGPaintServer(Color);
    explicit SVGPaintServer(PassRefPtr<Gradient>);
    explicit SVGPaintServer(PassRefPtr<Pattern>);

    static SVGPaintServer requestForLayoutObject(const LayoutObject&, const ComputedStyle&, LayoutSVGResourceMode);
    static bool existsForLayoutObject(const LayoutObject&, const ComputedStyle&, LayoutSVGResourceMode);

    void applyToSkPaint(SkPaint&, float paintAlpha);

    static SVGPaintServer invalid() { return SVGPaintServer(Color(Color::transparent)); }
    bool isValid() const { return m_color != Color::transparent; }

    bool isTransformDependent() const { return m_gradient || m_pattern; }
    void prependTransform(const AffineTransform&);

private:
    RefPtr<Gradient> m_gradient;
    RefPtr<Pattern> m_pattern;
    Color m_color;
};

// If |SVGPaintDescription::hasFallback| is true, |SVGPaintDescription::color| is set to a fallback color.
struct SVGPaintDescription {
    STACK_ALLOCATED();
    SVGPaintDescription() : resource(nullptr), isValid(false), hasFallback(false) { }
    SVGPaintDescription(Color color) : resource(nullptr), color(color), isValid(true), hasFallback(false) { }
    SVGPaintDescription(LayoutSVGResourcePaintServer* resource) : resource(resource), isValid(true), hasFallback(false) { ASSERT(resource); }
    SVGPaintDescription(LayoutSVGResourcePaintServer* resource, Color fallbackColor) : resource(resource), color(fallbackColor), isValid(true), hasFallback(true) { ASSERT(resource); }

    LayoutSVGResourcePaintServer* resource;
    Color color;
    bool isValid;
    bool hasFallback;
};

class LayoutSVGResourcePaintServer : public LayoutSVGResourceContainer {
public:
    LayoutSVGResourcePaintServer(SVGElement*);
    ~LayoutSVGResourcePaintServer() override;

    virtual SVGPaintServer preparePaintServer(const LayoutObject&) = 0;

    // Helper utilities used in to access the underlying resources for DRT.
    static SVGPaintDescription requestPaintDescription(const LayoutObject&, const ComputedStyle&, LayoutSVGResourceMode);
};

DEFINE_TYPE_CASTS(LayoutSVGResourcePaintServer, LayoutSVGResourceContainer, resource, resource->isSVGPaintServer(), resource.isSVGPaintServer());

} // namespace blink

#endif