nsrpagescache.cpp

#include "nsrpagescache.h"

/* Maximum cache size in bytes by default (100 MB) */
#define NSR_CORE_PAGES_CACHE_MAX_STORAGE 104857600

NSRPagesCache::NSRPagesCache (QObject *parent) :
		QObject (parent),
		_usedMemory (0),
		_maxMemory (NSR_CORE_PAGES_CACHE_MAX_STORAGE)
{
}

NSRPagesCache::~NSRPagesCache ()
{
	_hash.clear ();
	_pages.clear ();
}

bool
NSRPagesCache::isPageExists (int number) const
{
	return _hash.contains (number);
}

NSRRenderedPage
NSRPagesCache::getPage (int number) const
{
	return _hash.value (number);
}

void NSRPagesCache::setMaxMemory (qint64 maxMemory)
{
	if (maxMemory < 0 || maxMemory == _maxMemory)
		return;

	while (_usedMemory > _maxMemory && !_pages.isEmpty ()) {
		int deqPage = _pages.takeFirst ();

		NSRRenderedPage rpage = _hash.take (deqPage);

		_usedMemory -= (rpage.getSize().width () * rpage.getSize().height () * 4 +
				rpage.getText().size () * 2);
	}
}

void
NSRPagesCache::addPage (const NSRRenderedPage& page)
{
	qint64		newSize;
	int		deqPage;

	if (!page.isValid ())
		return;

	newSize = page.getSize().width () * page.getSize().height () * 4 +
		  page.getText().size () * 2;

	if (newSize > _maxMemory)
		return;

	_hash.take (page.getNumber ());
	_pages.removeAll (page.getNumber ());

	while ((_usedMemory + newSize) > _maxMemory && !_pages.isEmpty ()) {
		if (qAbs (page.getNumber () - _pages.first ()) <
		    qAbs (page.getNumber () - _pages.last ()))
			deqPage = _pages.takeLast ();
		else
			deqPage = _pages.takeFirst ();

		NSRRenderedPage rpage = _hash.take (deqPage);

		_usedMemory -= (rpage.getSize().width () * rpage.getSize().height () * 4 +
				rpage.getText().size () * 2);
	}

	NSRRenderedPage newPage = page;
	newPage.setRenderReason (NSRRenderRequest::NSR_RENDER_REASON_NAVIGATION);
	newPage.setCached (true);

	_pages.append (newPage.getNumber ());
	qSort (_pages);

	_hash.insert (newPage.getNumber (), newPage);
	_usedMemory += newSize;
}

void
NSRPagesCache::removePage (int number)
{
	if (number <= 0)
		return;

	NSRRenderedPage page = _hash.take (number);

	_pages.removeAll (number);

	if (!page.isValid ())
		return;

	_usedMemory -= (page.getSize().width () * page.getSize().height () * 4 +
			page.getText().size () * 2);
}

void
NSRPagesCache::clearStorage ()
{
	_hash.clear ();
	_pages.clear ();
	_usedMemory = 0;
}

void
NSRPagesCache::updatePagePositions (int number,
				    const QPointF& pos,
				    const QPointF& textPos)
{
	NSRRenderedPage page = _hash.value (number);

	if (!page.isValid ())
		return;

	page.setLastPosition (pos);
	page.setLastTextPosition (textPos);

	_hash.insert (number, page);
}

void
NSRPagesCache::removePagesWithoutImages ()
{
	int count = _pages.count ();
	for (int i = count - 1; i >= 0; --i)
		if (!_hash.value(_pages.at (i)).isImageValid ())
			removePage (_pages.at (i));
}

void
NSRPagesCache::removePagesWithImages ()
{
	int count = _pages.count ();
	for (int i = count - 1; i >= 0; --i)
		if (_hash.value(_pages.at (i)).isImageValid ())
			removePage (_pages.at (i));
}