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  #define Q_TEST_QPIXMAPCACHE
  #include "qpixmapcache.h"
  #include "qobject.h"
  #include "qdebug.h"
  #include "qpixmapcache_p.h"
  
  QT_BEGIN_NAMESPACE
  
  /*!
      \class QPixmapCache
      \inmodule QtGui
  
      \brief The QPixmapCache class provides an application-wide cache for pixmaps.
  
      This class is a tool for optimized drawing with QPixmap. You can
      use it to store temporary pixmaps that are expensive to generate
      without using more storage space than cacheLimit(). Use insert()
      to insert pixmaps, find() to find them, and clear() to empty the
      cache.
  
      QPixmapCache contains no member data, only static functions to
      access the global pixmap cache. It creates an internal QCache
      object for caching the pixmaps.
  
      The cache associates a pixmap with a user-provided string as a key,
      or with a QPixmapCache::Key that the cache generates.
      Using QPixmapCache::Key for keys is faster than using strings. The string API is
      very convenient for complex keys but the QPixmapCache::Key API will be very
      efficient and convenient for a one-to-one object-to-pixmap mapping - in
      this case, you can store the keys as members of an object.
  
      If two pixmaps are inserted into the cache using equal keys then the
      last pixmap will replace the first pixmap in the cache. This follows the
      behavior of the QHash and QCache classes.
  
      The cache becomes full when the total size of all pixmaps in the
      cache exceeds cacheLimit(). The initial cache limit is 10240 KB (10 MB);
      you can change this by calling setCacheLimit() with the required value.
      A pixmap takes roughly (\e{width} * \e{height} * \e{depth})/8 bytes of
      memory.
  
      The \e{Qt Quarterly} article
      \l{http://doc.qt.io/archives/qq/qq12-qpixmapcache.html}{Optimizing
      with QPixmapCache} explains how to use QPixmapCache to speed up
      applications by caching the results of painting.
  
      \sa QCache, QPixmap
  */
  
  static int cache_limit = 10240; // 10 MB cache limit
  
  /*!
      \class QPixmapCache::Key
      \brief The QPixmapCache::Key class can be used for efficient access
      to the QPixmapCache.
      \inmodule QtGui
      \since 4.6
  
      Use QPixmapCache::insert() to receive an instance of Key generated
      by the pixmap cache. You can store the key in your own objects for
      a very efficient one-to-one object-to-pixmap mapping.
  */
  
  /*!
      Constructs an empty Key object.
  */
  QPixmapCache::Key::Key() : d(0)
  {
  }
  
  /*!
     \internal
      Constructs a copy of \a other.
  */
  QPixmapCache::Key::Key(const Key &other)
  {
      if (other.d)
          ++(other.d->ref);
      d = other.d;
  }
  
  /*!
      Destroys the key.
  */
  QPixmapCache::Key::~Key()
  {
      if (d && --(d->ref) == 0)
          delete d;
  }
  
  /*!
      \internal
  
      Returns \c true if this key is the same as the given \a key; otherwise returns
      false.
  */
  bool QPixmapCache::Key::operator ==(const Key &key) const
  {
      return (d == key.d);
  }
  
  /*!
      \fn bool QPixmapCache::Key::operator !=(const Key &key) const
      \internal
  */
  
  /*!
      \fn QPixmapCache::Key::Key(Key &&)
      \internal
      \since 5.6
  */
  
  /*!
      \fn QPixmapCache::Key &QPixmapCache::Key::operator=(Key &&)
      \internal
      \since 5.6
  */
  
  /*!
      \fn void QPixmapCache::Key::swap(Key &)
      \internal
      \since 5.6
  */
  
  /*!
      \internal
  */
  QPixmapCache::Key &QPixmapCache::Key::operator =(const Key &other)
  {
      if (d != other.d) {
          if (other.d)
              ++(other.d->ref);
          if (d && --(d->ref) == 0)
              delete d;
          d = other.d;
      }
      return *this;
  }
  
  class QPMCache : public QObject, public QCache<QPixmapCache::Key, QPixmapCacheEntry>
  {
      Q_OBJECT
  public:
      QPMCache();
      ~QPMCache();
  
      void timerEvent(QTimerEvent *) Q_DECL_OVERRIDE;
      bool insert(const QString& key, const QPixmap &pixmap, int cost);
      QPixmapCache::Key insert(const QPixmap &pixmap, int cost);
      bool replace(const QPixmapCache::Key &key, const QPixmap &pixmap, int cost);
      bool remove(const QString &key);
      bool remove(const QPixmapCache::Key &key);
  
      void resizeKeyArray(int size);
      QPixmapCache::Key createKey();
      void releaseKey(const QPixmapCache::Key &key);
      void clear();
  
      QPixmap *object(const QString &key) const;
      QPixmap *object(const QPixmapCache::Key &key) const;
  
      static inline QPixmapCache::KeyData *get(const QPixmapCache::Key &key)
      {return key.d;}
  
      static QPixmapCache::KeyData* getKeyData(QPixmapCache::Key *key);
  
      bool flushDetachedPixmaps(bool nt);
  
  private:
      enum { soon_time = 10000, flush_time = 30000 };
      int *keyArray;
      int theid;
      int ps;
      int keyArraySize;
      int freeKey;
      QHash<QString, QPixmapCache::Key> cacheKeys;
      bool t;
  };
  
  QT_BEGIN_INCLUDE_NAMESPACE
  #include "qpixmapcache.moc"
  QT_END_INCLUDE_NAMESPACE
  
  uint qHash(const QPixmapCache::Key &k)
  {
      return qHash(QPMCache::get(k)->key);
  }
  
  QPMCache::QPMCache()
      : QObject(0),
        QCache<QPixmapCache::Key, QPixmapCacheEntry>(cache_limit * 1024),
        keyArray(0), theid(0), ps(0), keyArraySize(0), freeKey(0), t(false)
  {
  }
  QPMCache::~QPMCache()
  {
      clear();
      free(keyArray);
  }
  
  /*
    This is supposed to cut the cache size down by about 25% in a
    minute once the application becomes idle, to let any inserted pixmap
    remain in the cache for some time before it becomes a candidate for
    cleaning-up, and to not cut down the size of the cache while the
    cache is in active use.
  
    When the last detached pixmap has been deleted from the cache, kill the
    timer so Qt won't keep the CPU from going into sleep mode. Currently
    the timer is not restarted when the pixmap becomes unused, but it does
    restart once something else is added (i.e. the cache space is actually needed).
  
    Returns \c true if any were removed.
  */
  bool QPMCache::flushDetachedPixmaps(bool nt)
  {
      int mc = maxCost();
      setMaxCost(nt ? totalCost() * 3 / 4 : totalCost() -1);
      setMaxCost(mc);
      ps = totalCost();
  
      bool any = false;
      QHash<QString, QPixmapCache::Key>::iterator it = cacheKeys.begin();
      while (it != cacheKeys.end()) {
          if (!contains(it.value())) {
              releaseKey(it.value());
              it = cacheKeys.erase(it);
              any = true;
          } else {
              ++it;
          }
      }
  
      return any;
  }
  
  void QPMCache::timerEvent(QTimerEvent *)
  {
      bool nt = totalCost() == ps;
      if (!flushDetachedPixmaps(nt)) {
          killTimer(theid);
          theid = 0;
      } else if (nt != t) {
          killTimer(theid);
          theid = startTimer(nt ? soon_time : flush_time);
          t = nt;
      }
  }
  
  
  QPixmap *QPMCache::object(const QString &key) const
  {
      QPixmapCache::Key cacheKey = cacheKeys.value(key);
      if (!cacheKey.d || !cacheKey.d->isValid) {
          const_cast<QPMCache *>(this)->cacheKeys.remove(key);
          return 0;
      }
      QPixmap *ptr = QCache<QPixmapCache::Key, QPixmapCacheEntry>::object(cacheKey);
       //We didn't find the pixmap in the cache, the key is not valid anymore
      if (!ptr) {
          const_cast<QPMCache *>(this)->cacheKeys.remove(key);
      }
      return ptr;
  }
  
  QPixmap *QPMCache::object(const QPixmapCache::Key &key) const
  {
      Q_ASSERT(key.d->isValid);
      QPixmap *ptr = QCache<QPixmapCache::Key, QPixmapCacheEntry>::object(key);
      //We didn't find the pixmap in the cache, the key is not valid anymore
      if (!ptr)
          const_cast<QPMCache *>(this)->releaseKey(key);
      return ptr;
  }
  
  bool QPMCache::insert(const QString& key, const QPixmap &pixmap, int cost)
  {
      QPixmapCache::Key cacheKey;
      QPixmapCache::Key oldCacheKey = cacheKeys.value(key);
      //If for the same key we add already a pixmap we should delete it
      if (oldCacheKey.d) {
          QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(oldCacheKey);
          cacheKeys.remove(key);
      }
  
      //we create a new key the old one has been removed
      cacheKey = createKey();
  
      bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
      if (success) {
          cacheKeys.insert(key, cacheKey);
          if (!theid) {
              theid = startTimer(flush_time);
              t = false;
          }
      } else {
          //Insertion failed we released the new allocated key
          releaseKey(cacheKey);
      }
      return success;
  }
  
  QPixmapCache::Key QPMCache::insert(const QPixmap &pixmap, int cost)
  {
      QPixmapCache::Key cacheKey = createKey();
      bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
      if (success) {
          if (!theid) {
              theid = startTimer(flush_time);
              t = false;
          }
      } else {
          //Insertion failed we released the key and return an invalid one
          releaseKey(cacheKey);
      }
      return cacheKey;
  }
  
  bool QPMCache::replace(const QPixmapCache::Key &key, const QPixmap &pixmap, int cost)
  {
      Q_ASSERT(key.d->isValid);
      //If for the same key we had already an entry so we should delete the pixmap and use the new one
      QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(key);
  
      QPixmapCache::Key cacheKey = createKey();
  
      bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
      if (success) {
          if(!theid) {
              theid = startTimer(flush_time);
              t = false;
          }
          const_cast<QPixmapCache::Key&>(key) = cacheKey;
      } else {
          //Insertion failed we released the key
          releaseKey(cacheKey);
      }
      return success;
  }
  
  bool QPMCache::remove(const QString &key)
  {
      QPixmapCache::Key cacheKey = cacheKeys.value(key);
      //The key was not in the cache
      if (!cacheKey.d)
          return false;
      cacheKeys.remove(key);
      return QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(cacheKey);
  }
  
  bool QPMCache::remove(const QPixmapCache::Key &key)
  {
      return QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(key);
  }
  
  void QPMCache::resizeKeyArray(int size)
  {
      if (size <= keyArraySize || size == 0)
          return;
      keyArray = q_check_ptr(reinterpret_cast<int *>(realloc(keyArray,
                      size * sizeof(int))));
      for (int i = keyArraySize; i != size; ++i)
          keyArray[i] = i + 1;
      keyArraySize = size;
  }
  
  QPixmapCache::Key QPMCache::createKey()
  {
      if (freeKey == keyArraySize)
          resizeKeyArray(keyArraySize ? keyArraySize << 1 : 2);
      int id = freeKey;
      freeKey = keyArray[id];
      QPixmapCache::Key key;
      QPixmapCache::KeyData *d = QPMCache::getKeyData(&key);
      d->key = ++id;
      return key;
  }
  
  void QPMCache::releaseKey(const QPixmapCache::Key &key)
  {
      if (key.d->key > keyArraySize || key.d->key <= 0)
          return;
      key.d->key--;
      keyArray[key.d->key] = freeKey;
      freeKey = key.d->key;
      key.d->isValid = false;
      key.d->key = 0;
  }
  
  void QPMCache::clear()
  {
      free(keyArray);
      keyArray = 0;
      freeKey = 0;
      keyArraySize = 0;
      //Mark all keys as invalid
      QList<QPixmapCache::Key> keys = QCache<QPixmapCache::Key, QPixmapCacheEntry>::keys();
      for (int i = 0; i < keys.size(); ++i)
          keys.at(i).d->isValid = false;
      QCache<QPixmapCache::Key, QPixmapCacheEntry>::clear();
  }
  
  QPixmapCache::KeyData* QPMCache::getKeyData(QPixmapCache::Key *key)
  {
      if (!key->d)
          key->d = new QPixmapCache::KeyData;
      return key->d;
  }
  
  Q_GLOBAL_STATIC(QPMCache, pm_cache)
  
  int Q_AUTOTEST_EXPORT q_QPixmapCache_keyHashSize()
  {
      return pm_cache()->size();
  }
  
  QPixmapCacheEntry::~QPixmapCacheEntry()
  {
      pm_cache()->releaseKey(key);
  }
  
  /*!
      \obsolete
      \overload
  
      Returns the pixmap associated with the \a key in the cache, or
      null if there is no such pixmap.
  
      \warning If valid, you should copy the pixmap immediately (this is
      fast). Subsequent insertions into the cache could cause the
      pointer to become invalid. For this reason, we recommend you use
      bool find(const QString&, QPixmap*) instead.
  
      Example:
      \snippet code/src_gui_image_qpixmapcache.cpp 0
  */
  
  QPixmap *QPixmapCache::find(const QString &key)
  {
      return pm_cache()->object(key);
  }
  
  
  /*!
      \obsolete
  
      Use bool find(const QString&, QPixmap*) instead.
  */
  
  bool QPixmapCache::find(const QString &key, QPixmap& pixmap)
  {
      return find(key, &pixmap);
  }
  
  /*!
      Looks for a cached pixmap associated with the given \a key in the cache.
      If the pixmap is found, the function sets \a pixmap to that pixmap and
      returns \c true; otherwise it leaves \a pixmap alone and returns \c false.
  
      \since 4.6
  
      Example:
      \snippet code/src_gui_image_qpixmapcache.cpp 1
  */
  
  bool QPixmapCache::find(const QString &key, QPixmap* pixmap)
  {
      QPixmap *ptr = pm_cache()->object(key);
      if (ptr && pixmap)
          *pixmap = *ptr;
      return ptr != 0;
  }
  
  /*!
      Looks for a cached pixmap associated with the given \a key in the cache.
      If the pixmap is found, the function sets \a pixmap to that pixmap and
      returns \c true; otherwise it leaves \a pixmap alone and returns \c false. If
      the pixmap is not found, it means that the \a key is no longer valid,
      so it will be released for the next insertion.
  
      \since 4.6
  */
  bool QPixmapCache::find(const Key &key, QPixmap* pixmap)
  {
      //The key is not valid anymore, a flush happened before probably
      if (!key.d || !key.d->isValid)
          return false;
      QPixmap *ptr = pm_cache()->object(key);
      if (ptr && pixmap)
          *pixmap = *ptr;
      return ptr != 0;
  }
  
  /*!
      Inserts a copy of the pixmap \a pixmap associated with the \a key into
      the cache.
  
      All pixmaps inserted by the Qt library have a key starting with
      "$qt", so your own pixmap keys should never begin "$qt".
  
      When a pixmap is inserted and the cache is about to exceed its
      limit, it removes pixmaps until there is enough room for the
      pixmap to be inserted.
  
      The oldest pixmaps (least recently accessed in the cache) are
      deleted when more space is needed.
  
      The function returns \c true if the object was inserted into the
      cache; otherwise it returns \c false.
  
      \sa setCacheLimit()
  */
  
  bool QPixmapCache::insert(const QString &key, const QPixmap &pixmap)
  {
      return pm_cache()->insert(key, pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
  }
  
  /*!
      Inserts a copy of the given \a pixmap into the cache and returns a key
      that can be used to retrieve it.
  
      When a pixmap is inserted and the cache is about to exceed its
      limit, it removes pixmaps until there is enough room for the
      pixmap to be inserted.
  
      The oldest pixmaps (least recently accessed in the cache) are
      deleted when more space is needed.
  
      \sa setCacheLimit(), replace()
  
      \since 4.6
  */
  QPixmapCache::Key QPixmapCache::insert(const QPixmap &pixmap)
  {
      return pm_cache()->insert(pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
  }
  
  /*!
      Replaces the pixmap associated with the given \a key with the \a pixmap
      specified. Returns \c true if the \a pixmap has been correctly inserted into
      the cache; otherwise returns \c false.
  
      \sa setCacheLimit(), insert()
  
      \since 4.6
  */
  bool QPixmapCache::replace(const Key &key, const QPixmap &pixmap)
  {
      //The key is not valid anymore, a flush happened before probably
      if (!key.d || !key.d->isValid)
          return false;
      return pm_cache()->replace(key, pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
  }
  
  /*!
      Returns the cache limit (in kilobytes).
  
      The default cache limit is 10240 KB.
  
      \sa setCacheLimit()
  */
  
  int QPixmapCache::cacheLimit()
  {
      return cache_limit;
  }
  
  /*!
      Sets the cache limit to \a n kilobytes.
  
      The default setting is 10240 KB.
  
      \sa cacheLimit()
  */
  
  void QPixmapCache::setCacheLimit(int n)
  {
      cache_limit = n;
      pm_cache()->setMaxCost(1024 * cache_limit);
  }
  
  /*!
    Removes the pixmap associated with \a key from the cache.
  */
  void QPixmapCache::remove(const QString &key)
  {
      pm_cache()->remove(key);
  }
  
  /*!
    Removes the pixmap associated with \a key from the cache and releases
    the key for a future insertion.
  
    \since 4.6
  */
  void QPixmapCache::remove(const Key &key)
  {
      //The key is not valid anymore, a flush happened before probably
      if (!key.d || !key.d->isValid)
          return;
      pm_cache()->remove(key);
  }
  
  /*!
      Removes all pixmaps from the cache.
  */
  
  void QPixmapCache::clear()
  {
      QT_TRY {
          if (pm_cache.exists())
              pm_cache->clear();
      } QT_CATCH(const std::bad_alloc &) {
          // if we ran out of memory during pm_cache(), it's no leak,
          // so just ignore it.
      }
  }
  
  void QPixmapCache::flushDetachedPixmaps()
  {
      pm_cache()->flushDetachedPixmaps(true);
  }
  
  int QPixmapCache::totalUsed()
  {
      return (pm_cache()->totalCost()+1023) / 1024;
  }
  
  /*!
     \fn QPixmapCache::KeyData::KeyData()
  
     \internal
  */
  /*!
     \fn QPixmapCache::KeyData::KeyData(const KeyData &other)
     \internal
  */
  /*!
     \fn QPixmapCache::KeyData::~KeyData()
  
     \internal
  */
  QT_END_NAMESPACE
  