/*
 * This file is a part of Winix
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2012-2014, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <algorithm>
#include "ipbancontainer.h"
#include "log.h"
#include "date/date.h"


namespace Winix
{



IPBanContainer::IPBanContainer()
{
	is_ipban_tab_sorted	= true; // an empty list is sorted
	soft_max_size 		= 100;
	max_size 			= 110;
}


void IPBanContainer::SetMaxSize(size_t soft_size, size_t size)
{
	soft_max_size = soft_size;
	max_size      = size;

	if( max_size < soft_max_size )
		max_size = soft_max_size + 1;

	ipban_tab.reserve(max_size);
	sort_helper_tab.reserve(max_size);
}


// returning a reference to the added (or existed) record
IPBan & IPBanContainer::AddIP(int ip)
{
	IPBan * old_ip_ban = FindIP(ip);

	if( !old_ip_ban )
	{
		IPBan ip_ban;
		ip_ban.ip = ip;

		if( ipban_tab.size() >= max_size )
			RemoveOldRecords();

		ipban_tab.push_back(ip_ban);
		is_ipban_tab_sorted = false;
		return ipban_tab.back();
	}
	else
	{
		return *old_ip_ban;
	}
}


void IPBanContainer::RemoveIP(int ip)
{
	IPBan * ipban = FindIP(ip);

	if( ipban )
	{
		size_t index = ipban - &ipban_tab[0];
		ipban_tab.erase(ipban_tab.begin() + index);
	}
}


bool IPBanContainer::IsSorted()
{
	return is_ipban_tab_sorted;
}


void IPBanContainer::Clear()
{
	ipban_tab.clear();
	is_ipban_tab_sorted = true;
}


// we need to remove some old records for the size of the container
// to be less or equal to soft_max_size
void IPBanContainer::RemoveOldRecords()
{
	size_t to_remove = 0;

	if( ipban_tab.size() >= soft_max_size )
		to_remove = ipban_tab.size() - soft_max_size;

	if( to_remove > 0 )
	{
		sort_helper_tab.resize(ipban_tab.size());

		for(size_t i=0 ; i<ipban_tab.size() ; ++i)
			sort_helper_tab[i] = i;

		std::sort(sort_helper_tab.begin(), sort_helper_tab.end(), SortByLastUsedHelper(this));
		sort_helper_tab.resize(to_remove);
		std::sort(sort_helper_tab.begin(), sort_helper_tab.end());

		while( to_remove-- > 0 )
			ipban_tab.erase(ipban_tab.begin() + sort_helper_tab[to_remove]);
	}
}


// for debug purposes
void IPBanContainer::PrintTab()
{
	log << log4 << "ipban_tab (size: " << ipban_tab.size() << ")" << logend;

	for(size_t i=0 ; i<ipban_tab.size() ; ++i)
	{
		log << log4 << i << ": ip: " << ipban_tab[i].ip << ", flags: " << ipban_tab[i].flags << ", last_used: ";

		pt::Date date(ipban_tab[i].last_used);
		log << date << ", expires: ";

		date = ipban_tab[i].expires;
		log << date << logend;
	}
}


// for debug purposes
void IPBanContainer::PrintTab2()
{
	log << log4 << "sort_helper_tab (size: " << sort_helper_tab.size() << ")" << logend;

	for(size_t i=0 ; i<sort_helper_tab.size() ; ++i)
	{
		IPBan & ipban = ipban_tab[sort_helper_tab[i]];

		log << log4 << i << ": ip: " << ipban.ip << ", flags: " << ipban.flags << ", last_used: ";

		pt::Date date(ipban.last_used);
		log << date << ", expires: ";

		date = ipban.expires;
		log << date << logend;
	}
}


bool IPBanContainer::SortByLastUsedHelper::operator()(size_t index1, size_t index2)
{
	if( index1 < container->ipban_tab.size() &&
		index2 < container->ipban_tab.size() )
	{
		IPBan & ip1 = container->ipban_tab[index1];
		IPBan & ip2 = container->ipban_tab[index2];

		// prefer to select records which do not have WINIX_IPBAN_FLAG_ACTIVE
		if( ip1.HasFlag(WINIX_IPBAN_FLAG_ACTIVE) !=
			ip2.HasFlag(WINIX_IPBAN_FLAG_ACTIVE) )
		{
			return ip2.HasFlag(WINIX_IPBAN_FLAG_ACTIVE);
		}

		return ip1.last_used < ip2.last_used;
	}

return false;
}



IPBan * IPBanContainer::FindIP(int ip)
{
	// !! IMPROVE ME add binary search if is_ipban_tab_sorted is true

	for(size_t i=0 ; i<ipban_tab.size() ; ++i)
	{
		if( ipban_tab[i].ip == ip )
		{
			return &ipban_tab[i];
		}
	}

return 0;
}


IPBan & IPBanContainer::GetIPBan(size_t index)
{
	return ipban_tab[index];
}


void IPBanContainer::Sort()
{
	std::sort(ipban_tab.begin(), ipban_tab.end(), SortIPBansFunction);
	is_ipban_tab_sorted = true;
}



size_t IPBanContainer::Size()
{
	return ipban_tab.size();
}



bool IPBanContainer::SortIPBansFunction(const IPBan & ip1, const IPBan & ip2)
{
	return ip1.ip < ip2.ip;
}




} // namespace Winix