Source/core/css/resolver/StyleBuilderCustom.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
 *
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 * notice, this list of conditions and the following disclaimer.
 *     * 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.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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 THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 */

#ifndef StyleBuilderCustom_h
#define StyleBuilderCustom_h

#include "core/css/CSSValue.h"
#include "core/css/resolver/StyleResolverState.h"
#include "core/rendering/RenderView.h"
#include "core/svg/SVGLength.h"
#include "platform/LengthSize.h"

namespace WebCore {

// Note that we assume the parser only allows valid CSSValue types.

class StyleBuilderConverter {
public:
    template <typename T> static T convertComputedLength(StyleResolverState&, CSSValue*);
    template <typename T> static T convertLineWidth(StyleResolverState&, CSSValue*);
    static Length convertLength(StyleResolverState&, CSSValue*);
    static Length convertLengthOrAuto(StyleResolverState&, CSSValue*);
    static Length convertLengthSizing(StyleResolverState&, CSSValue*);
    static Length convertLengthMaxSizing(StyleResolverState&, CSSValue*);
    static LengthPoint convertLengthPoint(StyleResolverState&, CSSValue*);
    static LengthSize convertRadius(StyleResolverState&, CSSValue*);
    static float convertSpacing(StyleResolverState&, CSSValue*);
    template <CSSValueID IdForNone> static AtomicString convertString(StyleResolverState&, CSSValue*);
};

template <typename T>
T StyleBuilderConverter::convertComputedLength(StyleResolverState& state, CSSValue* value)
{
    float zoom = state.style()->effectiveZoom();
    return toCSSPrimitiveValue(value)->computeLength<T>(state.style(), state.rootElementStyle(), zoom);
}

template <typename T>
T StyleBuilderConverter::convertLineWidth(StyleResolverState& state, CSSValue* value)
{
    CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);
    CSSValueID valueID = primitiveValue->getValueID();
    if (valueID == CSSValueThin)
        return 1;
    if (valueID == CSSValueMedium)
        return 3;
    if (valueID == CSSValueThick)
        return 5;
    if (primitiveValue->isViewportPercentageLength())
        return intValueForLength(primitiveValue->viewportPercentageLength(), 0, state.document().renderView());
    if (valueID == CSSValueInvalid) {
        float zoom = state.style()->effectiveZoom();
        // Any original result that was >= 1 should not be allowed to fall below 1.
        // This keeps border lines from vanishing.
        T result = primitiveValue->computeLength<T>(state.style(), state.rootElementStyle(), zoom);
        if (zoom < 1.0f && result < 1.0) {
            T originalLength = primitiveValue->computeLength<T>(state.style(), state.rootElementStyle(), 1.0);
            if (originalLength >= 1.0)
                return 1.0;
        }
        return result;
    }
    ASSERT_NOT_REACHED();
    return 0;
}

template <CSSValueID IdForNone>
AtomicString StyleBuilderConverter::convertString(StyleResolverState&, CSSValue* value)
{
    CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);
    if (primitiveValue->getValueID() == IdForNone)
        return nullAtom;
    return primitiveValue->getStringValue();
}

} // namespace WebCore

#endif