/*
 * ZeroTier One - Network Virtualization Everywhere
 * Copyright (C) 2011-2015  ZeroTier, Inc.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 * --
 *
 * ZeroTier may be used and distributed under the terms of the GPLv3, which
 * are available at: http://www.gnu.org/licenses/gpl-3.0.html
 *
 * If you would like to embed ZeroTier into a commercial application or
 * redistribute it in a modified binary form, please contact ZeroTier Networks
 * LLC. Start here: http://www.zerotier.com/
 */

#ifndef ZT_NODE_HPP
#define ZT_NODE_HPP

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <map>

#include "Constants.hpp"

#include "../include/ZeroTierOne.h"

#include "InetAddress.hpp"
#include "Mutex.hpp"
#include "MAC.hpp"
#include "Network.hpp"

namespace ZeroTier {

class RuntimeEnvironment;

/**
 * Implementation of Node object as defined in CAPI
 *
 * The pointer returned by ZT1_Node_new() is an instance of this class.
 */
class Node
{
public:
	Node(
		ZT1_DataStoreGetFunction *dataStoreGetFunction,
		ZT1_DataStorePutFunction *dataStorePutFunction,
		ZT1_WirePacketSendFunction *wirePacketSendFunction,
		ZT1_VirtualNetworkFrameFunction *virtualNetworkFrameFunction,
		ZT1_VirtualNetworkConfigCallback *virtualNetworkConfigCallback,
		ZT1_StatusCallback *statusCallback);

	~Node();

	// Public API Functions ----------------------------------------------------

	ZT1_ResultCode processWirePacket(
		uint64_t now,
		const struct sockaddr_storage *remoteAddress,
		int linkDesperation,
		const void *packetData,
		unsigned int packetLength,
		uint64_t *nextCallDeadline);
	ZT1_ResultCode processVirtualNetworkFrame(
		uint64_t now,
		uint64_t nwid,
		uint64_t sourceMac,
		uint64_t destMac,
		unsigned int etherType,
		unsigned int vlanId,
		const void *frameData,
		unsigned int frameLength,
		uint64_t *nextCallDeadline);
	ZT1_Resultcode processNothing(uint64_t now,uint64_t *nextCallDeadline);
	ZT1_ResultCode join(uint64_t nwid);
	ZT1_ResultCode leave(uint64_t nwid);
	ZT1_ResultCode multicastSubscribe(ZT1_Node *node,uint64_t nwid,uint64_t multicastGroup,unsigned long multicastAdi = 0);
	ZT1_ResultCode multicastUnsubscribe(ZT1_Node *node,uint64_t nwid,uint64_t multicastGroup,unsigned long multicastAdi = 0);
	void status(ZT1_NodeStatus *status);
	ZT1_PeerList *peers();
	ZT1_VirtualNetworkConfig *networkConfig(uint64_t nwid);
	ZT1_VirtualNetworkList *listNetworks();
	void freeQueryResult(void *qr);
	void setNetconfMaster(void *networkConfigMasterInstance);

	// Internal functions ------------------------------------------------------

	/**
	 * @return Time as of last call to run()
	 */
	inline uint64_t now() const throw() { return _now; }

	/**
	 * @return Current level of desperation
	 */
	inline int desperation() const throw() { return (int)((_now - _timeOfLastPrivilgedPacket) / ZT_DESPERATION_INCREMENT); }

	/**
	 * Called to update last packet receive time whenever a packet is received
	 *
	 * @param fromPrivilegedPeer If true, peer is a supernode or federated hub (a.k.a. an upstream link)
	 */
	inline void packetReceived(bool fromPrivilegedPeer)
		throw()
	{
		const uint64_t n = _now;
		_timeOfLastPacketReceived = n;
		if (fromPrivilegedPeer)
			_timeOfLastPrivilgedPacket = n;
	}

	/**
	 * @return Most recent time of any packet receipt
	 */
	inline uint64_t timeOfLastPacketReceived() const throw() { return _timeOfLastPacketReceived; }

	/**
	 * @return Timestamp of last packet received from a supernode or hub (upstream link)
	 */
	inline uint64_t timeOfLastPrivilgedPacket() const throw() { return _timeOfLastPrivilgedPacket; }

	/**
	 * Enqueue a ZeroTier message to be sent
	 *
	 * @param addr Destination address
	 * @param data Packet data
	 * @param len Packet length
	 */
	inline void putPacket(const InetAddress &addr,const void *data,unsigned int len)
	{
		_wirePacketSendFunction(
			reinterpret_cast<ZT1_Node *>(this),
			reinterpret_cast<const struct sockaddr_storage *>(&addr),
			this->desperation(),
			(int)((++_spamCounter % ZT_DESPERATION_SPAM_EVERY) == 0),
			data,
			len);
	}

	/**
	 * Enqueue a frame to be injected into a tap device (port)
	 *
	 * @param nwid Network ID
	 * @param source Source MAC
	 * @param dest Destination MAC
	 * @param etherType 16-bit ethernet type
	 * @param vlanId VLAN ID or 0 if none
	 * @param data Frame data
	 * @param len Frame length
	 */
	inline void putFrame(uint64_t nwid,const MAC &source,const MAC &dest,unsigned int etherType,unsigned int vlanId,const void *data,unsigned int len)
	{
		_virtualNetworkFrameFunction(
			reinterpret_cast<ZT1_Node *>(this),
			nwid,
			source.toInt(),
			dest.toInt(),
			etherType,
			vlanId,
			data,
			len);
	}

	/**
	 * @param nwid Network ID
	 * @return Network instance
	 */
	inline SharedPtr<Network> network(uint64_t nwid)
	{
		Mutex::Lock _l(_networks_m);
		std::map< uint64_t,SharedPtr<Network> >::iterator nw(_networks.find(nwid));
		return ((nw == _networks.end()) ? SharedPtr<Network>() : nw->second);
	}

private:
	RuntimeEnvironment *RR;

	ZT1_DataStoreGetFunction *_dataStoreGetFunction;
	ZT1_DataStorePutFunction *_dataStorePutFunction;
	ZT1_WirePacketSendFunction *_wirePacketSendFunction;
	ZT1_VirtualNetworkFrameFunction *_virtualNetworkFrameFunction;
	ZT1_VirtualNetworkConfigCallback *_virtualNetworkConfigCallback;
	ZT1_StatusCallback *_statusCallback;

	//Dictionary _localConfig; // persisted as local.conf
	//Mutex _localConfig_m;

	std::map< uint64_t,SharedPtr<Network> > _networks;
	Mutex _networks_m;

	volatile uint64_t _now; // time of last run()
	volatile uint64_t _timeOfLastPacketReceived;
	volatile _timeOfLastPrivilgedPacket;
	volatile unsigned int _spamCounter; // used to "spam" every Nth packet
};

} // namespace ZeroTier

#endif