// Copyright © 2010-2012 b0ris
//.
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

#include <QTimer>
#include "UpdatedConfig.h"


UpdatedConfig* UpdatedConfig::self = NULL;

UpdatedConfig* UpdatedConfig::CurrentConfig()
{
	if (self == NULL)
		self = new UpdatedConfig();
	return self;
}

string UpdatedConfig::GetServerAddr()
{
	if (! configValid)
	{
		Logger::Error("No valid server records present!\n");
		return string("");
	}
	string ret = servers[activeSrvIndex].host;
	return ret;
}

UpdatedConfig::UpdatedConfig()
{
	activeSrvIndex = 0;
	time = 0;
	retryFailed = false;
	updateStatus = 0;
	
	if (servers.size() == 0)
	{
		Logger::Error("No server records present. Can't update configuration!\n");
		return;
	}
	
	client = new SslClient(QString::fromLocal8Bit(servers[0].host.c_str()));
	connect(client, SIGNAL(ReplyRecieved(SslClient::RequestType&, QByteArray&)),
			this, SLOT(gotServerReply(SslClient::RequestType&, QByteArray&)));
	connect(client, SIGNAL(ConnectionError()),
			this, SLOT(connectionError()));
	
	configUpdateTimer = new QTimer;
	configUpdateTimer->setInterval(servers[activeSrvIndex].retryTimeout * 1000);
	connect(configUpdateTimer, SIGNAL(timeout()),
			this, SLOT(update()));
	configUpdateTimer->stop();
	
	update();
}

void UpdatedConfig::update()
{
	Logger::Trace("Going to update configuration\n");
	configValid = false;
	
	if (retryFailed)
	{
		/* count retries and switch between server records */
		time += servers[activeSrvIndex].retryTimeout;
		Logger::Trace("Previous connection attempt failed or there were connection problems\n");
		if (time >= servers[activeSrvIndex].timeout)
		{
			time = 0;
			activeSrvIndex++;
			if (activeSrvIndex == servers.size())
			{
				activeSrvIndex = 0;
			}
			ServerEntry current = servers[activeSrvIndex];
			client->SetServerAddr(QString::fromLocal8Bit(current.host.c_str()));
			configUpdateTimer->stop();
			configUpdateTimer->setInterval(current.retryTimeout * 1000);
			configUpdateTimer->start();
		}
		retryFailed = false;
	}
	
	if (! (updateStatus & (1 << SslClient::Config)))
	{
		client->SendRequest(SslClient::Config);
	}
	else if (! (updateStatus & (1 << SslClient::GenericProxyList)))
	{
		client->SendRequest(SslClient::GenericProxyList);
	}
	else if (! (updateStatus & (1 << SslClient::StaticProxyList)))
	{
		client->SendRequest(SslClient::StaticProxyList);
	}
	else if (! (updateStatus & (1 << SslClient::FirewallList)))
	{
		client->SendRequest(SslClient::FirewallList);
	}
	else if (! (updateStatus & (1 << SslClient::DownloadList)))
	{
		client->SendRequest(SslClient::DownloadList);
	}
	else if (! (updateStatus & (1 << SslClient::DeleteList)))
	{
		client->SendRequest(SslClient::DeleteList);
	}
	else
	{
		Logger::Warn("Unknown config update status: %x\n", updateStatus);
	}
}

void UpdatedConfig::connectionError()
{
	retryFailed = true;
	Logger::Trace("Connection error. Starting reconnection timer\n");
	
	/* start update timer (the case if working server is no longer responding) */
	if (! configUpdateTimer->isActive())
	{
		time = 0;
		configUpdateTimer->start();
	}
}

void UpdatedConfig::gotServerReply(SslClient::RequestType &type, QByteArray &confdata)
{
	Logger::Trace("Got server reply w type: %x\n", type);
	if (confdata.size() == 0)
	{
		Logger::Warn("Empty server reply recieved\n");
		goto end;
	}
	
	//Logger::Debug("data: %s\n", confdata.constData());
	
	/* stop timer - working server found */
	configUpdateTimer->stop();
	
	switch (type)
	{
		case SslClient::Config:
			ParseConfig(confdata.constData());
			Logger::Debug("Config data:\n %s", confdata.constData());
			break;
		case SslClient::GenericProxyList:
			ParseGenericProxies(confdata.constData());
			break;
		case SslClient::StaticProxyList:
			ParseStaticProxies(confdata.constData());
			break;
		case SslClient::FirewallList:
			ParseFirewalls(confdata.constData());
			break;
		case SslClient::DownloadList:
			ParseDownloadList(confdata.constData());
			break;
		case SslClient::DeleteList:
			ParseDeleteList(confdata.constData());
			break;
		default:
			Logger::Warn("Unknown reply type: %x\n", type);
			break;
	}
	
end:
	updateStatus |= (1 << type);
	
	if (updateStatus != UPDATED_STATE_FULL)
	{
		Logger::Trace("Still need to update other config parts. Update status: %x\n", updateStatus);
		update();
	}
	else
	{
		Logger::Info("Config successfully updated!\n");
		client->Disconnect();
		configValid = true;
		
		// reset retry params and setup timer to fire on next planned update
		// but leave activeSrvIndex as it is, so we will reconnect to the same working serv next time
		time = 0;
		updateStatus = 0;
		retryFailed = false;
		
		configUpdateTimer->stop();
		configUpdateTimer->setInterval(updateInterval * 1000);
		if (! configUpdateTimer->isActive())
		{
			configUpdateTimer->start();
		}
		emit updated();
	}
}