/*
* Copyright (c) 2006 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description:
*
*/
#ifndef MediaQueryEvaluator_h
#define MediaQueryEvaluator_h
#include "PlatformString.h"
namespace WebCore {
class Page;
class RenderStyle;
class MediaList;
class MediaQueryExp;
/**
* Class that evaluates css media queries as defined in
* CSS3 Module "Media Queries" (http://www.w3.org/TR/css3-mediaqueries/)
* Special constructors are needed, if simple media queries are to be
* evaluated without knowledge of the medium features. This can happen
* for example when parsing UA stylesheets, if evaluation is done
* right after parsing.
*
* the boolean parameter is used to approximate results of evaluation, if
* the device characteristics are not known. This can be used to prune the loading
* of stylesheets to only those which are probable to match.
*/
class MediaQueryEvaluator
{
public:
/** Creates evaluator which evaluates only simple media queries
* Evaluator returns true for "all", and returns value of \mediaFeatureResult
* for any media features
*/
MediaQueryEvaluator(bool mediaFeatureResult = false);
/** Creates evaluator which evaluates only simple media queries
* Evaluator returns true for acceptedMediaType and returns value of \mediafeatureResult
* for any media features
*/
MediaQueryEvaluator(const String& acceptedMediaType, bool mediaFeatureResult = false);
MediaQueryEvaluator(const char* acceptedMediaType, bool mediaFeatureResult = false);
/** Creates evaluator which evaluates full media queries
*/
MediaQueryEvaluator(const String& acceptedMediaType, Page* page, RenderStyle* style);
~MediaQueryEvaluator();
bool mediaTypeMatch(const String& mediaTypeToMatch) const;
bool mediaTypeMatchSpecific(const char* mediaTypeToMatch) const;
/** Evaluates a list of media queries */
bool eval(const MediaList* query) const;
/** Evaluates media query subexpression, ie "and (media-feature: value)" part */
bool eval(const MediaQueryExp* expr) const;
private:
String m_mediaType;
Page* m_page; // not owned
RenderStyle* m_style; // not owned
bool m_expResult;
};
} // namespace
#endif