mediaqueryevaluator.cpp

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    return colorMediaFeatureEval(value, style, frame, op);
}

static bool device_aspect_ratioMediaFeatureEval(CSSValue* value, RenderStyle*, Frame* frame, MediaFeaturePrefix op)
{
    if (value) {
        FloatRect sg = screenRect(frame->page()->mainFrame()->view());
        int h = 0;
        int v = 0;
        if (parseAspectRatio(value, h, v))
            return v != 0  && compareValue(static_cast<int>(sg.width()) * v, static_cast<int>(sg.height()) * h, op);
        return false;
    }

    // ({,min-,max-}device-aspect-ratio)
    // assume if we have a device, its aspect ratio is non-zero
    return true;
}

static bool device_pixel_ratioMediaFeatureEval(CSSValue *value, RenderStyle*, Frame* frame, MediaFeaturePrefix op)
{
    if (value)
        return value->isPrimitiveValue() && compareValue(frame->page()->chrome()->scaleFactor(), static_cast<CSSPrimitiveValue*>(value)->getFloatValue(), op);

    return frame->page()->chrome()->scaleFactor() != 0;
}

static bool gridMediaFeatureEval(CSSValue* value, RenderStyle*, Frame*, MediaFeaturePrefix op)
{
    // if output device is bitmap, grid: 0 == true
    // assume we have bitmap device
    float number;
    if (value && numberValue(value, number))
        return compareValue(static_cast<int>(number), 0, op);
    return false;
}

static bool device_heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix op)
{
    if (value) {
        FloatRect sg = screenRect(frame->page()->mainFrame()->view());
        return value->isPrimitiveValue() && compareValue(static_cast<int>(sg.height()), static_cast<CSSPrimitiveValue*>(value)->computeLengthInt(style), op);
    }
    // ({,min-,max-}device-height)
    // assume if we have a device, assume non-zero
    return true;
}

static bool device_widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix op)
{
    if (value) {
        FloatRect sg = screenRect(frame->page()->mainFrame()->view());
        return value->isPrimitiveValue() && compareValue(static_cast<int>(sg.width()), static_cast<CSSPrimitiveValue*>(value)->computeLengthInt(style), op);
    }
    // ({,min-,max-}device-width)
    // assume if we have a device, assume non-zero
    return true;
}

static bool heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix op)
{
    FrameView* view = frame->view();
    
    if (value)
        return value->isPrimitiveValue() && compareValue(view->layoutHeight(), static_cast<CSSPrimitiveValue*>(value)->computeLengthInt(style), op);

    return view->layoutHeight() != 0;
}

static bool widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix op)
{
    FrameView* view = frame->view();
    
    if (value)
        return value->isPrimitiveValue() && compareValue(view->layoutWidth(), static_cast<CSSPrimitiveValue*>(value)->computeLengthInt(style), op);

    return view->layoutWidth() != 0;
}

// rest of the functions are trampolines which set the prefix according to the media feature expression used

static bool min_colorMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return colorMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_colorMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return colorMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_monochromeMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return monochromeMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_monochromeMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return monochromeMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_device_aspect_ratioMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_aspect_ratioMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_device_aspect_ratioMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_aspect_ratioMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_device_pixel_ratioMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_pixel_ratioMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_device_pixel_ratioMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_pixel_ratioMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return heightMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return heightMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return widthMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return widthMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_device_heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_heightMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_device_heightMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_heightMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool min_device_widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_widthMediaFeatureEval(value, style, frame, MinPrefix);
}

static bool max_device_widthMediaFeatureEval(CSSValue* value, RenderStyle* style, Frame* frame, MediaFeaturePrefix)
{
    return device_widthMediaFeatureEval(value, style, frame, MaxPrefix);
}

static bool animationMediaFeatureEval(CSSValue* value, RenderStyle*, Frame*, MediaFeaturePrefix op)
{
    if (value) {
        float number;
        return numberValue(value, number) && compareValue(1, static_cast<int>(number), op);
    }
    return true;
}

static bool transitionMediaFeatureEval(CSSValue* value, RenderStyle*, Frame*, MediaFeaturePrefix op)
{
    if (value) {
        float number;
        return numberValue(value, number) && compareValue(1, static_cast<int>(number), op);
    }
    return true;
}

static bool transform_2dMediaFeatureEval(CSSValue* value, RenderStyle*, Frame*, MediaFeaturePrefix op)
{
    if (value) {
        float number;
        return numberValue(value, number) && compareValue(1, static_cast<int>(number), op);
    }
    return true;
}

static bool transform_3dMediaFeatureEval(CSSValue* value, RenderStyle*, Frame*, MediaFeaturePrefix op)
{
    if (value) {
        float number;
        return numberValue(value, number) && compareValue(0, static_cast<int>(number), op);
    }
    return false;
}

static void createFunctionMap()
{
    // Create the table.
    gFunctionMap = new FunctionMap;
#define ADD_TO_FUNCTIONMAP(name, str)  \
    gFunctionMap->set(name##MediaFeature.impl(), name##MediaFeatureEval);
    CSS_MEDIAQUERY_NAMES_FOR_EACH_MEDIAFEATURE(ADD_TO_FUNCTIONMAP);
#undef ADD_TO_FUNCTIONMAP
}

bool MediaQueryEvaluator::eval(const MediaQueryExp* expr) const
{
    if (!m_frame || !m_style)
        return m_expResult;

    if (!gFunctionMap)
        createFunctionMap();

    // call the media feature evaluation function. Assume no prefix
    // and let trampoline functions override the prefix if prefix is
    // used
    EvalFunc func = gFunctionMap->get(expr->mediaFeature().impl());
    if (func)
        return func(expr->value(), m_style, m_frame, NoPrefix);

    return false;
}

} // namespace