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(KwCssSchema* schema, KwCssScope* parent)
  39 : m_schema(schema)
  40 , m_parentScope(parent)
  41 , m_childScopes()
  42 , m_name()
  43 , m_classes()
  44 , m_styleSheets()
  45 , m_styles()
  46 {
  47   if (0 != m_parentScope)
  48   {
  49     parent->m_childScopes.insert(this);
  50   }
  51 }
  52
  53 /// Destructor.
  54 KwCssScope::~KwCssScope()
  55 {
  56   // Remove from parent's child list.
  57   if (0 != m_parentScope)
  58   {
  59     m_parentScope->m_childScopes.remove(this);
  60   }
  61
  62   // Remove from children and recalculate styles.
  63   {
  64     ScopeSet::iterator it;
  65     for (it = m_childScopes.begin(); it != m_childScopes.end(); ++it)
  66     {
  67       (*it)->m_parentScope = 0;
  68       (*it)->recalculateStyles();
  69     }
  70   }
  71
  72   // Clean style sheets
  73   {
  74     foreach (KwCssStyleSheet* stylesheet, m_styleSheets)
  75     {
  76       /// @todo reference count
  77       delete stylesheet;
  78     }
  79   }
  80 }
  81
  82 /*
  83  * DOM filters
  84  */
  85
  86 /// Import the style information from a DOM.
  87 void KwCssScope::importStylesFromDom(const QDomElement& element, KwResourceManager* resourceManager)
  88 {
  89   Q_UNUSED(resourceManager);
  90   // Classes
  91   QDomNodeList elems = element.elementsByTagName("class");
  92   for (int i = 0; i < elems.count(); ++i)
  93   {
  94     m_classes += elems.at(i).toElement().text();
  95   }
  96
  97   // Stylesheets
  98   elems = element.elementsByTagName("sheet");
  99   for (int i = 0; i < elems.count(); ++i)
 100   {
 101     KwCssStyleSheet* newSheet = new KwCssStyleSheet;
 102     newSheet->import(m_schema, elems.at(i).toElement().text());
 103     m_styleSheets.push_back(newSheet);
 104   }
 105   if (elems.count() > 0)
 106   {
 107     recalculateStyles();
 108   }
 109
 110   // Explicit styles
 111   elems = element.elementsByTagName("explicit");
 112   for (int i = 0; i < elems.count(); ++i)
 113   {
 114     QString styles = elems.at(i).toElement().text();
 115     int last = m_styles.import(m_schema, styles);
 116     /// @todo Check it got to the end of the styles
 117   }
 118 }
 119
 120 /// Export the style information to a DOM.
 121 void KwCssScope::exportStylesToDom(QDomDocument& document, QDomElement& element, KwResourceManager* resourceManager) const
 122 {
 123   Q_UNUSED(resourceManager);
 124   // Start with the classes
 125   foreach (QString className, m_classes)
 126   {
 127     QDomElement classElem = document.createElement("class");
 128     element.appendChild(classElem);
 129     classElem.appendChild(document.createTextNode(className));
 130   }
 131
 132   // Now for the stylesheets
 133   foreach (KwCssStyleSheet* stylesheet, m_styleSheets)
 134   {
 135     QDomElement sheetElem = document.createElement("sheet");
 136     element.appendChild(sheetElem);
 137     sheetElem.appendChild(document.createTextNode(stylesheet->toString()));
 138   }
 139
 140   // And finally the explicit styles
 141   if (!m_styles.isEmpty())
 142   {
 143     QDomElement explicitElem = document.createElement("explicit");
 144     element.appendChild(explicitElem);
 145     explicitElem.appendChild(document.createTextNode(m_styles.toString()));
 146   }
 147 }
 148
 149 /*
 150  * Main interface
 151  */
 152
 153 /// Add a stylesheet for this scope.
 154 void KwCssScope::addStyleSheet(KwCssStyleSheet* styleSheet)
 155 {
 156   m_styleSheets.push_back(styleSheet);
 157   recalculateStyles();
 158 }
 159
 160 /// Add a class to this scope.
 161 void KwCssScope::addClass(QString className)
 162 {
 163   m_classes += className;
 164   recalculateStyles();
 165 }
 166
 167 /// Get all the styles included in this scope.
 168 const KwCssStyleStates& KwCssScope::getStyles() const
 169 {
 170   return m_cachedStyles;
 171 }
 172
 173 /// Recalculate all styles.
 174 void KwCssScope::recalculateStyles()
 175 {
 176   /*
 177    * cached styles
 178    * unmatched rules stylesheet
 179    *
 180    * get parent styles
 181    * add classes
 182    * get parent unmatched style rules
 183    * go through stylesheets
 184    *  apply any rules that match in order, removing as we go from local list
 185    * apply explicit styles
 186    */
 187   // Get the base styles from the parent
 188   if (0 != m_parentScope)
 189   {
 190     m_cachedStyles = m_parentScope->getStyles();
 191     m_cachedStyleSheet = m_parentScope->m_cachedStyleSheet;
 192     m_cachedClasses = m_parentScope->m_cachedClasses;
 193   }
 194   else
 195   {
 196     m_cachedStyles.clear();
 197     m_cachedStyleSheet.clear();
 198   }
 199   // Add local stylesheets
 200   {
 201     StyleSheetList::iterator it;
 202     for (it = m_styleSheets.begin(); it != m_styleSheets.end(); ++it)
 203     {
 204       m_cachedStyleSheet.importStyleSheet(*it);
 205     }
 206   }
 207   // Add local classes
 208   m_cachedClasses += m_classes;
 209
 210   // process rules
 211   bool processRules;
 212   do
 213   {
 214     processRules = false;
 215     QSet<QString> triggerableClasses;
 216     KwCssStyleSheet::Iterator it;
 217     for (it = m_cachedStyleSheet.getRules().begin(); it != m_cachedStyleSheet.getRules().end();)
 218     {
 219       // Match the keys
 220       KwCssStyleRule::KeyList& keys = (*it).getCriteriaKeys();
 221       if (!keys.empty() && isKeyMatching(keys.first()))
 222       {
 223         keys.pop_front();
 224       }
 225       // Match the classes
 226       KwCssStyleRule::StringSet& classes = (*it).getCriteriaClasses();
 227       classes -= m_cachedClasses;
 228
 229       if (!classes.empty())
 230       {
 231         triggerableClasses += classes;
 232         ++it;
 233       }
 234       else if (keys.empty())
 235       {
 236         // Nothing left to match, we can apply this style and remove it from the list
 237         m_cachedStyles << *(*it).getStyles();
 238         QSet<QString> classesToApply = (*it).getIncludedStyles() - m_cachedClasses;
 239         if (!classesToApply.empty())
 240         {
 241           m_cachedClasses += classesToApply;
 242           QSet<QString> classesToTrigger = triggerableClasses & classesToApply;
 243           if (!classesToTrigger.empty())
 244           {
 245             triggerableClasses -= classesToTrigger;
 246             processRules = true;
 247           }
 248         }
 249         // Remove from stylesheet since it's now applied
 250         KwCssStyleSheet::Iterator cur = it;
 251         ++it;
 252         m_cachedStyleSheet.getRules().erase(cur);
 253       }
 254       else
 255       {
 256         ++it;
 257       }
 258     }
 259   }
 260   while (processRules);
 261
 262   // Apply each style
 263   m_cachedStyles << m_styles;
 264
 265   // Recurse to children
 266   {
 267     ScopeSet::iterator it;
 268     for (it = m_childScopes.begin(); it != m_childScopes.end(); ++it)
 269     {
 270       (*it)->recalculateStyles();
 271     }
 272   }
 273 }
 274
 275 /*
 276  * Accessors
 277  */
 278
 279 /// Find whether the scope is effectively empty.
 280 bool KwCssScope::isScopeEmpty() const
 281 {
 282   return m_classes.isEmpty() && m_styleSheets.isEmpty() && m_styles.isEmpty();
 283 }
 284
 285 /// Get explicit styles.
 286 const KwCssStyles& KwCssScope::getExplicitStyles() const
 287 {
 288   return m_styles;
 289 }
 290
 291 /// Get the scope's key.
 292 KwCssScopeKey KwCssScope::getKey() const
 293 {
 294   return KwCssScopeKey(getTypeId(), m_name);
 295 }
 296
 297 /// Find whether a scope key matches this scope.
 298 bool KwCssScope::isKeyMatching(KwCssScopeKey key) const
 299 {
 300   return (!key.isTypeSpecified() || key.getTypeId() == getTypeId())
 301       && (!key.isNameSpecified() || key.getName()   == m_name);
 302 }
 303
 304 /*
 305  * Mutators
 306  */
 307
 308 /// Set the parent scope.
 309 void KwCssScope::setParentScope(KwCssScope* parent)
 310 {
 311   if (0 != m_parentScope)
 312   {
 313     m_parentScope->m_childScopes.remove(this);
 314   }
 315   m_parentScope = parent;
 316   if (0 != parent)
 317   {
 318     m_parentScope->m_childScopes.insert(this);
 319   }
 320   recalculateStyles();
 321 }
 322