kworship/css/KwCssScope.cpp

   1 /***************************************************************************
   2  *   This file is part of KWorship.                                        *
   3  *   Copyright 2008 James Hogan <james@albanarts.com>                      *
   4  *                                                                         *
   5  *   KWorship is free software: you can redistribute it and/or modify      *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation, either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   KWorship is distributed in the hope that it will be useful,           *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with KWorship.  If not, write to the Free Software Foundation,  *
  17  *   Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.   *
  18  ***************************************************************************/
  19
  20 /**
  21  * @file KwCssScope.cpp
  22  * @brief Cascading style scope.
  23  * @author James Hogan <james@albanarts.com>
  24  */
  25
  26 #include "KwCssScope.h"
  27 #include "KwCssStyleRule.h"
  28 #include "KwCssStyleSheet.h"
  29
  30 #include <QDomDocument>
  31 #include <QDomElement>
  32
  33 /*
  34  * Constructors + destructors
  35  */
  36
  37 /// Primary constructor.
  38 KwCssScope::KwCssScope(KwCssScope* parent)
  39 : m_parentScope(parent)
  40 , m_childScopes()
  41 , m_name()
  42 , m_classes()
  43 , m_styleSheets()
  44 , m_styles()
  45 {
  46   if (0 != m_parentScope)
  47   {
  48     parent->m_childScopes.insert(this);
  49   }
  50 }
  51
  52 /// Destructor.
  53 KwCssScope::~KwCssScope()
  54 {
  55   // Remove from parent's child list.
  56   if (0 != m_parentScope)
  57   {
  58     m_parentScope->m_childScopes.remove(this);
  59   }
  60
  61   // Remove from children and recalculate styles.
  62   {
  63     ScopeSet::iterator it;
  64     for (it = m_childScopes.begin(); it != m_childScopes.end(); ++it)
  65     {
  66       (*it)->m_parentScope = 0;
  67       (*it)->recalculateStyles();
  68     }
  69   }
  70
  71   // Clean style sheets
  72   {
  73     foreach (KwCssStyleSheet* stylesheet, m_styleSheets)
  74     {
  75       /// @todo reference count
  76       delete stylesheet;
  77     }
  78   }
  79 }
  80
  81 /*
  82  * DOM filters
  83  */
  84
  85 /// Import the style information from a DOM.
  86 void KwCssScope::importStylesFromDom(const QDomElement& element, KwResourceManager* resourceManager)
  87 {
  88   // Classes
  89   QDomNodeList elems = element.elementsByTagName("class");
  90   for (int i = 0; i < elems.count(); ++i)
  91   {
  92     m_classes += elems.at(i).toElement().text();
  93   }
  94
  95   // Stylesheets
  96   elems = element.elementsByTagName("sheet");
  97   for (int i = 0; i < elems.count(); ++i)
  98   {
  99     KwCssStyleSheet* newSheet = new KwCssStyleSheet;
 100     newSheet->import(elems.at(i).toElement().text());
 101     m_styleSheets.push_back(newSheet);
 102   }
 103   if (elems.count() > 0)
 104   {
 105     recalculateStyles();
 106   }
 107
 108   // Explicit styles
 109   elems = element.elementsByTagName("explicit");
 110   for (int i = 0; i < elems.count(); ++i)
 111   {
 112     m_styles.import(elems.at(i).toElement().text());
 113   }
 114 }
 115
 116 /// Export the style information to a DOM.
 117 void KwCssScope::exportStylesToDom(QDomDocument& document, QDomElement& element, KwResourceManager* resourceManager) const
 118 {
 119   // Start with the classes
 120   foreach (QString className, m_classes)
 121   {
 122     QDomElement classElem = document.createElement("class");
 123     element.appendChild(classElem);
 124     classElem.appendChild(document.createTextNode(className));
 125   }
 126
 127   // Now for the stylesheets
 128   foreach (KwCssStyleSheet* stylesheet, m_styleSheets)
 129   {
 130     QDomElement sheetElem = document.createElement("sheet");
 131     element.appendChild(sheetElem);
 132     sheetElem.appendChild(document.createTextNode(stylesheet->toString()));
 133   }
 134
 135   // And finally the explicit styles
 136   if (!m_styles.isEmpty())
 137   {
 138     QDomElement explicitElem = document.createElement("explicit");
 139     element.appendChild(explicitElem);
 140     explicitElem.appendChild(document.createTextNode(m_styles.toString()));
 141   }
 142 }
 143
 144 /*
 145  * Main interface
 146  */
 147
 148 /// Add a stylesheet for this scope.
 149 void KwCssScope::addStyleSheet(KwCssStyleSheet* styleSheet)
 150 {
 151   m_styleSheets.push_back(styleSheet);
 152   recalculateStyles();
 153 }
 154
 155 /// Add a class to this scope.
 156 void KwCssScope::addClass(QString className)
 157 {
 158   m_classes += className;
 159   recalculateStyles();
 160 }
 161
 162 /// Get all the styles included in this scope.
 163 const KwCssStyleStates& KwCssScope::getStyles() const
 164 {
 165   return m_cachedStyles;
 166 }
 167
 168 /// Recalculate all styles.
 169 void KwCssScope::recalculateStyles()
 170 {
 171   /*
 172    * cached styles
 173    * unmatched rules stylesheet
 174    *
 175    * get parent styles
 176    * add classes
 177    * get parent unmatched style rules
 178    * go through stylesheets
 179    *  apply any rules that match in order, removing as we go from local list
 180    * apply explicit styles
 181    */
 182   // Get the base styles from the parent
 183   if (0 != m_parentScope)
 184   {
 185     m_cachedStyles = m_parentScope->getStyles();
 186     m_cachedStyleSheet = m_parentScope->m_cachedStyleSheet;
 187     m_cachedClasses = m_parentScope->m_cachedClasses;
 188   }
 189   else
 190   {
 191     m_cachedStyles.clear();
 192     m_cachedStyleSheet.clear();
 193   }
 194   // Add local stylesheets
 195   {
 196     StyleSheetList::iterator it;
 197     for (it = m_styleSheets.begin(); it != m_styleSheets.end(); ++it)
 198     {
 199       m_cachedStyleSheet.importStyleSheet(*it);
 200     }
 201   }
 202   // Add local classes
 203   m_cachedClasses += m_classes;
 204
 205   // process rules
 206   bool processRules;
 207   do
 208   {
 209     processRules = false;
 210     QSet<QString> triggerableClasses;
 211     KwCssStyleSheet::Iterator it;
 212     for (it = m_cachedStyleSheet.getRules().begin(); it != m_cachedStyleSheet.getRules().end();)
 213     {
 214       // Match the keys
 215       KwCssStyleRule::KeyList& keys = (*it).getCriteriaKeys();
 216       if (!keys.empty() && isKeyMatching(keys.first()))
 217       {
 218         keys.pop_front();
 219       }
 220       // Match the classes
 221       KwCssStyleRule::StringSet& classes = (*it).getCriteriaClasses();
 222       classes -= m_cachedClasses;
 223
 224       if (!classes.empty())
 225       {
 226         triggerableClasses += classes;
 227         ++it;
 228       }
 229       else if (keys.empty())
 230       {
 231         // Nothing left to match, we can apply this style and remove it from the list
 232         m_cachedStyles << *(*it).getStyles();
 233         QSet<QString> classesToApply = (*it).getIncludedStyles() - m_cachedClasses;
 234         if (!classesToApply.empty())
 235         {
 236           m_cachedClasses += classesToApply;
 237           QSet<QString> classesToTrigger = triggerableClasses & classesToApply;
 238           if (!classesToTrigger.empty())
 239           {
 240             triggerableClasses -= classesToTrigger;
 241             processRules = true;
 242           }
 243         }
 244         // Remove from stylesheet since it's now applied
 245         KwCssStyleSheet::Iterator cur = it;
 246         ++it;
 247         m_cachedStyleSheet.getRules().erase(cur);
 248       }
 249       else
 250       {
 251         ++it;
 252       }
 253     }
 254   }
 255   while (processRules);
 256
 257   // Apply each style
 258   m_cachedStyles << m_styles;
 259
 260   // Recurse to children
 261   {
 262     ScopeSet::iterator it;
 263     for (it = m_childScopes.begin(); it != m_childScopes.end(); ++it)
 264     {
 265       (*it)->recalculateStyles();
 266     }
 267   }
 268 }
 269
 270 /*
 271  * Accessors
 272  */
 273
 274 /// Find whether the scope is effectively empty.
 275 bool KwCssScope::isScopeEmpty() const
 276 {
 277   return m_classes.isEmpty() && m_styleSheets.isEmpty() && m_styles.isEmpty();
 278 }
 279
 280 /// Get explicit styles.
 281 const KwCssStyles& KwCssScope::getExplicitStyles() const
 282 {
 283   return m_styles;
 284 }
 285
 286 /// Get the scope's key.
 287 KwCssScopeKey KwCssScope::getKey() const
 288 {
 289   return KwCssScopeKey(getTypeId(), m_name);
 290 }
 291
 292 /// Find whether a scope key matches this scope.
 293 bool KwCssScope::isKeyMatching(KwCssScopeKey key) const
 294 {
 295   return (!key.isTypeSpecified() || key.getTypeId() == getTypeId())
 296       && (!key.isNameSpecified() || key.getName()   == m_name);
 297 }
 298
 299 /*
 300  * Mutators
 301  */
 302
 303 /// Set the parent scope.
 304 void KwCssScope::setParentScope(KwCssScope* parent)
 305 {
 306   if (0 != m_parentScope)
 307   {
 308     m_parentScope->m_childScopes.remove(this);
 309   }
 310   m_parentScope = parent;
 311   if (0 != parent)
 312   {
 313     m_parentScope->m_childScopes.insert(this);
 314   }
 315   recalculateStyles();
 316 }
 317