/*
 * This file is a part of CMSLU -- Content Management System like Unix
 * and is not publicly distributed
 * 
 * Copyright (c) 2008, Tomasz Sowa
 * All rights reserved.
 * 
 */
 
#include "patterncacher.h"


PatternCacher::PatternCacher()
{
	// !! tymczasowe wartosci dla testow
	when_delete_patterns = 3; // 130
	how_many_delete      = 2; // 30
}



void PatternCacher::CheckTableSize()
{
	if( pattern_tab.size() < when_delete_patterns )
		return;
		
	PatternTab::iterator i;	
	PatternErase pe;
	size_t erase_index;
	
	erase_tab.resize(pattern_tab.size());
	
	for( i=pattern_tab.begin(), erase_index=0 ; i!=pattern_tab.end() ; ++i, ++erase_index)
	{
		pe.used = i->second.used;
		pe.iter = i;
		
		erase_tab[erase_index] = pe;
	}

	// sorting through 'used'
	std::sort(erase_tab.begin(), erase_tab.end());	

	for(erase_index = 0 ; erase_index<how_many_delete && erase_index<erase_tab.size() ; ++erase_index)
	{
		log << log2 << "PC: deleting from cache, id: " << erase_tab[erase_index].iter->second.item_id << logend;

		pattern_tab.erase(erase_tab[erase_index].iter);
	}
}



void PatternCacher::CreatePattern(const Item & item, Ezc::Pattern & pattern)
{
	pattern.allow_include = false;
	pattern.ParseString(item.content);
}




Ezc::Pattern * PatternCacher::AddPattern(const Item & item)
{
	CheckTableSize();

	PatternUsed pu;
	
	CreatePattern(item, pu.pattern);
	pu.used    = 1;
	pu.item_id = item.id;

	std::pair<PatternTab::iterator, bool> res = pattern_tab.insert( std::make_pair(item.id, pu) );
	
	log << log2 << "PC: added an item, id: " << item.id << ", url: " << item.url << logend;

return &(res.first->second.pattern);
}




Ezc::Pattern * PatternCacher::GetPattern(const Item & item)
{
PatternTab::iterator i;
	
	i = pattern_tab.find(item.id);
		
	if( i == pattern_tab.end() )
		return AddPattern(item);	
	else
	{
		log << log2 << "PC: taking a pattern from the cache, id: " << item.id << ", url: " << item.url << logend;
		++(i->second.used);
		return &(i->second.pattern);
	}
}



void PatternCacher::UpdatePattern(const Item & item)
{
PatternTab::iterator i;
	
	i = pattern_tab.find(item.id);
		
	if( i == pattern_tab.end() )
	{
		log << log2 << "PC: there is no such an item to update, id: " << item.id << ", url: " << item.url << logend;
		return;
	}
		
	++(i->second.used);
	CreatePattern(item, i->second.pattern);
	
	log << log2 << "PC: updated pattern, id: " << item.id << ", url: " << item.url << logend;
}



void PatternCacher::DeletePattern(const Item & item)
{
PatternTab::iterator i;
	
	i = pattern_tab.find(item.id);
		
	if( i == pattern_tab.end() )
	{
		log << log2 << "PC: there is no such an item to delete, id: " << item.id << ", url: " << item.url << logend;
		return;
	}		

	log << log2 << "PC: deleted pattern, id: " << item.id << ", url: " << item.url << logend;

	pattern_tab.erase(i);
}