/*
* Copyright(c) 1997-2001 Id Software, Inc.
* Copyright(c) 2002 The Quakeforge Project.
* Copyright(c) 2006 Quetoo.
*
* 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 "qcommon.h"

#include <unistd.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/uio.h>
#include <errno.h>

netadr_t net_local_adr;

#define LOOPBACK 0x7f000001

#define MAX_LOOPBACK 4

typedef struct {
	byte data[MAX_MSGLEN];
	int datalen;
} loopmsg_t;

typedef struct {
	loopmsg_t msgs[MAX_LOOPBACK];
	int get, send;
} loopback_t;

loopback_t loopbacks[2];
int ip_sockets[2];

int NET_Socket(char *net_interface, int port);
char *NET_ErrorString(void);


void NetadrToSockadr(netadr_t *a, struct sockaddr_in *s){
	memset(s, 0, sizeof(*s));
	
	if(a->type == NA_IP_BROADCAST){
		s->sin_family = AF_INET;
		
		s->sin_port = a->port;
		*(int *)&s->sin_addr = -1;
	} else if(a->type == NA_IP){
		s->sin_family = AF_INET;
		
		*(int *)&s->sin_addr = *(int *) & a->ip;
		s->sin_port = a->port;
	}
}


void SockadrToNetadr(struct sockaddr_in *s, netadr_t *a){
	*(int *)&a->ip = *(int *)&s->sin_addr;
	a->port = s->sin_port;
	a->type = NA_IP;
}


qboolean NET_CompareAdr(netadr_t a, netadr_t b){
	if(a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2]
			&& a.ip[3] == b.ip[3] && a.port == b.port)
		return true;
	return false;
}


/*
NET_CompareBaseAdr
 
Compares without the port
*/
qboolean NET_CompareBaseAdr(netadr_t a, netadr_t b){
	
	if(a.type != b.type)
		return false;
		
	if(a.type == NA_LOOPBACK)
		return true;
		
	if(a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2]
			&& a.ip[3] == b.ip[3])
		return true;
	
	return false;
}


char *NET_AdrToString(netadr_t a){
	static char s[64];
	
	Com_sprintf(s, sizeof(s), "%i.%i.%i.%i:%i", a.ip[0], a.ip[1],
			a.ip[2], a.ip[3], ntohs(a.port));
	return s;
}


char *NET_BaseAdrToString(netadr_t a){
	static char s[64];
	
	Com_sprintf(s, sizeof(s), "%i.%i.%i.%i", a.ip[0], a.ip[1],
			a.ip[2], a.ip[3]);
	return s;
}

/*
NET_StringToAdr
 
localhost
idnewt
idnewt:28000
192.246.40.70
192.246.40.70:28000
*/
qboolean NET_StringToSockaddr(char *s, struct sockaddr *sadr){
	struct hostent *h;
	char *colon;
	char copy[128];
	
	memset(sadr, 0, sizeof(*sadr));
	((struct sockaddr_in *)sadr)->sin_family = AF_INET;
	
	((struct sockaddr_in *)sadr)->sin_port = 0;
	
	strcpy(copy, s);
	// strip off a trailing :port if present
	for(colon = copy; *colon; colon++)
		if(*colon == ':'){
			*colon = 0;
			((struct sockaddr_in *)sadr)->sin_port = htons((short)atoi(colon + 1));
		}
		
	if(copy[0] >= '0' && copy[0] <= '9'){
		*(int *)&((struct sockaddr_in *)sadr)->sin_addr = inet_addr(copy);
	} else {
		if(!(h = gethostbyname(copy)))
			return 0;
		*(int *)&((struct sockaddr_in *)sadr)->sin_addr = *(int *)h->h_addr_list[0];
	}
	
	return true;
}

/*
NET_StringToAdr
 
localhost
idnewt
idnewt:28000
192.246.40.70
192.246.40.70:28000
*/
qboolean NET_StringToAdr(char *s, netadr_t *a){
	struct sockaddr_in sadr;
	
	if(!strcmp(s, "localhost")){
		memset(a, 0, sizeof(*a));
		a->type = NA_LOOPBACK;
		return true;
	}
	
	if(!NET_StringToSockaddr(s,(struct sockaddr *)&sadr))
		return false;
		
	SockadrToNetadr(&sadr, a);
	
	return true;
}


qboolean NET_IsLocalAddress(netadr_t adr){
	return NET_CompareAdr(adr, net_local_adr);
}

/*
 
LOOPBACK BUFFERS FOR LOCAL PLAYER
 
*/

qboolean NET_GetLoopPacket(netsrc_t sock, netadr_t *net_from, sizebuf_t *net_message){
	int i;
	loopback_t *loop;
	
	loop = &loopbacks[sock];
	
	if(loop->send - loop->get > MAX_LOOPBACK)
		loop->get = loop->send - MAX_LOOPBACK;
		
	if(loop->get >= loop->send)
		return false;
		
	i = loop->get & (MAX_LOOPBACK - 1);
	loop->get
	++;
	
	memcpy(net_message->data, loop->msgs[i].data, loop->msgs[i].datalen);
	net_message->cursize = loop->msgs[i].datalen;
	*net_from = net_local_adr;
	return true;
}


void NET_SendLoopPacket(netsrc_t sock, int length, void *data, netadr_t to){
	int i;
	loopback_t *loop;
	
	loop = &loopbacks[sock ^ 1];
	
	i = loop->send &(MAX_LOOPBACK - 1);
	loop->send++;
	
	memcpy(loop->msgs[i].data, data, length);
	loop->msgs[i].datalen = length;
}


qboolean NET_GetPacket(netsrc_t sock, netadr_t *net_from, sizebuf_t *net_message){
	int ret, err;
	struct sockaddr_in from;
	socklen_t fromlen;
	
	if(NET_GetLoopPacket(sock, net_from, net_message))
		return true;
	
	if(!ip_sockets[sock])
		return false;
	
	fromlen = sizeof(from);
	ret = recvfrom(ip_sockets[sock], net_message->data, 
		net_message->maxsize, 0, (struct sockaddr *)&from, &fromlen);
						
	SockadrToNetadr(&from, net_from);
		
	if(ret == -1){
		err = errno;
		
		if(err == EWOULDBLOCK || err == ECONNREFUSED)
			return false;  //not terribly abnormal
		
		Com_Printf("NET_GetPacket: %s from %s\n", NET_ErrorString(), NET_AdrToString(*net_from));
		return false;
	}
		
	if(ret == net_message->maxsize){
		Com_Printf("Oversize packet from %s\n", NET_AdrToString(*net_from));
		return false;
	}
		
	net_message->cursize = ret;
	return true;
}


void NET_SendPacket(netsrc_t sock, int length, void *data, netadr_t to){
	int ret;
	struct sockaddr_in addr;
	int net_socket;
	
	if(to.type == NA_LOOPBACK){
		NET_SendLoopPacket(sock, length, data, to);
		return;
	}
	
	if(to.type == NA_IP_BROADCAST){
		net_socket = ip_sockets[sock];
		if(!net_socket)
			return;
	} else if(to.type == NA_IP){
		net_socket = ip_sockets[sock];
		if(!net_socket)
			return;
	} else {
		Com_Error(ERR_FATAL, "NET_SendPacket: bad address type");
		return;
	}
	
	NetadrToSockadr(&to, &addr);
	
	ret = sendto(net_socket, data, length, 0, (struct sockaddr *)&addr, sizeof(addr));
	
	if(ret == -1){
		Com_Printf("NET_SendPacket ERROR: %s to %s\n",
			NET_ErrorString(), NET_AdrToString(to));
	}
}


/*
NET_OpenIP
*/
void NET_OpenIP(void){
	cvar_t *port, *ip;
	
	port = Cvar_Get("port", va("%i", PORT_SERVER), CVAR_NOSET);
	ip = Cvar_Get("ip", "localhost", CVAR_NOSET);
	
	if(!ip_sockets[NS_SERVER])
		ip_sockets[NS_SERVER] = NET_Socket(ip->string, port->value);
	if(!ip_sockets[NS_CLIENT])
		ip_sockets[NS_CLIENT] = NET_Socket(ip->string, PORT_ANY);
}


/*
NET_Config
 
A single player game will only use the loopback code
*/
void NET_Config(qboolean multiplayer){
	int i;
	
	if(!multiplayer){  // shut down any existing sockets
		for(i = 0; i < 2; i++){
			if(ip_sockets[i]){
				close(ip_sockets[i]);
				ip_sockets[i] = 0;
			}
		}
	} else {  // open sockets
		NET_OpenIP();
	}
}


/*
NET_Init
*/
void NET_Init(void){}


/*
NET_Socket
*/
int NET_Socket(char *net_interface, int port){
	int newsocket;
	struct sockaddr_in address;
	qboolean _true = true;
	int i = 1;
	
	if((newsocket = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1){
		Com_Printf("ERROR: UDP_OpenSocket: socket: %s", NET_ErrorString());
		return 0;
	}
	
	// make it non-blocking
	if(ioctl(newsocket, FIONBIO, &_true) == -1){
		Com_Printf("ERROR: UDP_OpenSocket: ioctl FIONBIO:%s\n", NET_ErrorString());
		return 0;
	}
	
	// make it broadcast capable
	if(setsockopt(newsocket, SOL_SOCKET, SO_BROADCAST,(char *)&i, sizeof(i)) == -1){
		Com_Printf("ERROR: UDP_OpenSocket: setsockopt SO_BROADCAST:%s\n", NET_ErrorString());
		return 0;
	}
	
	if(!net_interface || !net_interface[0] || !strcasecmp(net_interface, "localhost"))
		address.sin_addr.s_addr = INADDR_ANY;
	else
		NET_StringToSockaddr(net_interface, (struct sockaddr *)&address);
		
	if(port == PORT_ANY)
		address.sin_port = 0;
	else
		address.sin_port = htons((short)port);
		
	address.sin_family = AF_INET;
	
	if(bind(newsocket, (void *)&address, sizeof(address)) == -1){
		Com_Printf("ERROR: UDP_OpenSocket: bind: %s\n", NET_ErrorString());
		close(newsocket);
		return 0;
	}
	
	return newsocket;
}


/*
NET_Shutdown
*/
void NET_Shutdown(void){
	NET_Config(false);  // close sockets
}


/*
NET_ErrorString
*/
char *NET_ErrorString(void){
	int code;
	
	code = errno;
	return strerror(code);
}

// sleeps msec or until net socket is ready
void NET_Sleep(int msec){
	struct timeval timeout;
	fd_set fdset;
	extern cvar_t *dedicated;
	extern qboolean stdin_active;
	
	if(!ip_sockets[NS_SERVER] || !dedicated->value)
		return; // we're not a server, just run full speed
		
	FD_ZERO(&fdset);
	if(stdin_active)
		FD_SET(0, &fdset); // stdin is processed too
	FD_SET(ip_sockets[NS_SERVER], &fdset); // network socket
	timeout.tv_sec = msec / 1000;
	timeout.tv_usec = (msec % 1000) * 1000;
	select(ip_sockets[NS_SERVER] + 1, &fdset, NULL, NULL, &timeout);
}