/*
 *  VWE fork: NE2000 backend that tunnels guest Ethernet frames over Steam
 *  (`backend=steam`), so a private group can fly missions over the internet.
 *
 *  Why L2 and not an ordinary L3 tunnel: the 1995 mesh (WATTCP + netnub +
 *  L4NetworkManager) dials peers by raw IP on one flat subnet and ARPs for
 *  them, so whole FRAMES have to cross the internet for the DOS binaries to
 *  see the same-switch world they were built for.
 *
 *  All of the transport lives in vwesteam:: (steamlink.h) and is shared
 *  VERBATIM with the host's steam<->pcap gateway; this class is only the
 *  EthernetConnection adapter -- config resolution, the receive-side
 *  acceptance policy, and the log lines. Steamworks is bound at runtime in
 *  there, exactly as the pcap backend binds WPCAP.DLL, so a build on a machine
 *  with no SDK still runs and just fails Initialize() with a readable reason.
 *
 *  Only REMOTE players run this. The session host's pod stays on
 *  backend=pcap and reaches the tunnel through the gateway, which is what
 *  keeps exactly one process per machine on ISteamNetworkingMessages.
 *
 *  Conf:  [ne2000] backend=steam, macaddr=<stable MAC, never "random">
 *         [ethernet, steam] peers= lobby= session= channel=
 *  Contracts: ../steam/SESSION-CONTRACT.md (session file, env, addressing).
 */

#ifndef DOSBOX_ETHERNET_STEAM_H
#define DOSBOX_ETHERNET_STEAM_H

#include "config.h"

#ifdef WIN32

#include "ethernet.h"

#include <stdint.h>

/** A Steam-P2P Ethernet connection
 * Carries raw Ethernet frames to the other pods in the session over
 * SteamNetworkingMessages instead of over a host NIC. Needs Steam running,
 * a stable [ne2000] macaddr, and a peer roster (session file, csv or lobby).
 */
class SteamEthernetConnection : public EthernetConnection {
	public:
		SteamEthernetConnection();
		~SteamEthernetConnection();
		bool Initialize(Section* config) override;
		void SendPacket(const uint8_t* packet, int len) override;
		void GetPackets(std::function<void(const uint8_t*, int)> callback) override;

	private:
		uint8_t mac[6] = {};  /*!< [ne2000] macaddr; the RX filter's "ether dst self" */
		bool up = false;      /*!< Init() took -- gates the refcounted Shutdown() */
};

#endif

#endif