File indexing completed on 2024-04-28 15:22:39

 /*
  * CSS Media Query
  *
  * Copyright (C) 2006 Kimmo Kinnunen <kimmo.t.kinnunen@nokia.com>.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. 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.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef css_mediaquery_h
 #define css_mediaquery_h
 
 #include "dom/dom_string.h"
 #include "css/css_valueimpl.h"
 
 class KHTMLPart;
 
 namespace DOM
 {
 class MediaListImpl;
 class ValueList;
 }
 
 namespace khtml
 {
 
 class MediaQueryExp;
 
 class MediaQuery
 {
 public:
     enum Restrictor {
         Only, Not, None
     };
 
     MediaQuery(Restrictor r, const DOM::DOMString &mediaType, QList<MediaQueryExp *> *exprs);
     ~MediaQuery();
 
     Restrictor restrictor() const
     {
         return m_restrictor;
     }
     const QList<MediaQueryExp *> *expressions() const
     {
         return m_expressions;
     }
     DOM::DOMString mediaType() const
     {
         return m_mediaType;
     }
     bool operator==(const MediaQuery &other) const;
     void append(MediaQueryExp *newExp)
     {
         m_expressions->append(newExp);
     }
     DOM::DOMString cssText() const;
 
 private:
     Restrictor m_restrictor;
     DOM::DOMString m_mediaType;
     QList<MediaQueryExp *> *m_expressions;
 };
 
 class CSSStyleSelector;
 class RenderStyle;
 class MediaQueryExp;
 
 /**
  * Class that evaluates css media queries as defined in
  * CSS3 Module "Media Queries" (https://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 DOM::DOMString &acceptedMediaType, bool mediaFeatureResult = false);
     MediaQueryEvaluator(const char *acceptedMediaType, bool mediaFeatureResult = false);
 
     /** Creates evaluator which evaluates full media queries
      */
     MediaQueryEvaluator(const DOM::DOMString &acceptedMediaType, KHTMLPart *, RenderStyle *);
 
     ~MediaQueryEvaluator();
 
     bool mediaTypeMatch(const DOM::DOMString &mediaTypeToMatch) const;
     bool mediaTypeMatchSpecific(const char *mediaTypeToMatch) const;
 
     /** Evaluates a list of media queries */
     bool eval(const DOM::MediaListImpl *, CSSStyleSelector * = nullptr) const;
 
     /** Evaluates media query subexpression, ie "and (media-feature: value)" part */
     bool eval(const MediaQueryExp *) const;
 
     static void cleanup();
 
 private:
     DOM::DOMString m_mediaType;
     KHTMLPart *m_part; // not owned
     RenderStyle *m_style; // not owned
     bool m_expResult;
 };
 
 class MediaQueryExp
 {
 public:
     MediaQueryExp(const DOM::DOMString &mediaFeature, DOM::ValueList *values);
     ~MediaQueryExp();
 
     DOM::DOMString mediaFeature() const
     {
         return m_mediaFeature;
     }
 
     DOM::CSSValueImpl *value() const
     {
         return m_value;
     }
 
     bool operator==(const MediaQueryExp &other) const
     {
         return (other.m_mediaFeature == m_mediaFeature)
                && ((!other.m_value && !m_value)
                    || (other.m_value && m_value && other.m_value->cssText() == m_value->cssText()));
     }
 
     bool isViewportDependent() const
     {
         return m_viewportDependent;
     }
 
 private:
     bool m_viewportDependent;
     DOM::DOMString m_mediaFeature;
     DOM::CSSValueImpl *m_value;
 };
 
 } // namespace
 
 #endif