/*
Copyright (C) 1996-1997 Id Software, 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 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

*/
// net_loop.c

#include "quakedef.h"
#include "net_loop.h"
#include "client.h"
#include "server.h"
#include "console.h"
#include "sys.h"

qboolean localconnectpending = false;
qsocket_t *loop_client = NULL;
qsocket_t *loop_server = NULL;

int
Loop_Init(void)
{
    if (cls.state == ca_dedicated)
	return -1;
    return 0;
}

void
Loop_AddCommands()
{
}

void
Loop_RegisterVariables()
{
}

void
Loop_Shutdown(void)
{
}


void
Loop_Listen(qboolean state)
{
}


void
Loop_SearchForHosts(qboolean xmit)
{
    if (!sv.active)
	return;

    hostCacheCount = 1;
    if (strcmp(hostname.string, "UNNAMED") == 0)
	strcpy(hostcache[0].name, "local");
    else
	strcpy(hostcache[0].name, hostname.string);
    strcpy(hostcache[0].map, sv.name);
    hostcache[0].users = net_activeconnections;
    hostcache[0].maxusers = svs.maxclients;
    hostcache[0].driver = net_driver;
    strcpy(hostcache[0].cname, "local");
}


qsocket_t *
Loop_Connect(const char *host)
{
    if (strcmp(host, "local") != 0)
	return NULL;

    localconnectpending = true;

    if (!loop_client) {
	if ((loop_client = NET_NewQSocket()) == NULL) {
	    Con_Printf("Loop_Connect: no qsocket available\n");
	    return NULL;
	}
	strcpy(loop_client->address, "localhost");
    }
    loop_client->receiveMessageLength = 0;
    loop_client->sendMessageLength = 0;
    loop_client->canSend = true;
    loop_client->mtu = Loop_GetDefaultMTU();

    if (!loop_server) {
	if ((loop_server = NET_NewQSocket()) == NULL) {
	    Con_Printf("Loop_Connect: no qsocket available\n");
	    return NULL;
	}
	strcpy(loop_server->address, "LOCAL");
    }
    loop_server->receiveMessageLength = 0;
    loop_server->sendMessageLength = 0;
    loop_server->canSend = true;
    loop_server->mtu = Loop_GetDefaultMTU();

    loop_client->driverdata = (void *)loop_server;
    loop_server->driverdata = (void *)loop_client;

    return loop_client;
}


qsocket_t *
Loop_CheckNewConnections(void)
{
    if (!localconnectpending)
	return NULL;

    localconnectpending = false;
    loop_server->sendMessageLength = 0;
    loop_server->receiveMessageLength = 0;
    loop_server->canSend = true;
    loop_client->sendMessageLength = 0;
    loop_client->receiveMessageLength = 0;
    loop_client->canSend = true;
    return loop_server;
}


static int
IntAlign(int value)
{
    return (value + (sizeof(int) - 1)) & (~(sizeof(int) - 1));
}


int
Loop_GetMessage(qsocket_t *sock)
{
    int ret;
    int length;

    if (sock->receiveMessageLength == 0)
	return 0;

    ret = sock->receiveMessage[0];
    length =
          ((int)sock->receiveMessage[1] <<  0)
        + ((int)sock->receiveMessage[2] <<  8)
        + ((int)sock->receiveMessage[3] << 16);

    SZ_Clear(&net_message);
    SZ_Write(&net_message, &sock->receiveMessage[4], length);

    length = IntAlign(length + 4);
    sock->receiveMessageLength -= length;

    if (sock->receiveMessageLength)
	memmove(sock->receiveMessage, &sock->receiveMessage[length],
	       sock->receiveMessageLength);

    if (sock->driverdata && ret == 1)
	((qsocket_t *)sock->driverdata)->canSend = true;

    return ret;
}


int
Loop_SendMessage(qsocket_t *sock, const sizebuf_t *data)
{
    byte *buffer;
    int *bufferLength;

    if (!sock->driverdata)
	return -1;

    bufferLength = &((qsocket_t *)sock->driverdata)->receiveMessageLength;

    if ((*bufferLength + data->cursize + 4) > NET_MAXMESSAGE)
	Sys_Error("%s: overflow", __func__);

    buffer = ((qsocket_t *)sock->driverdata)->receiveMessage + *bufferLength;

    // message type
    *buffer++ = 1;

    // length
    *buffer++ = (data->cursize >>  0) & 0xff;
    *buffer++ = (data->cursize >>  8) & 0xff;
    *buffer++ = (data->cursize >> 16) & 0xff;

    // message
    memcpy(buffer, data->data, data->cursize);
    *bufferLength = IntAlign(*bufferLength + data->cursize + 4);

    sock->canSend = false;
    return 1;
}


int
Loop_SendUnreliableMessage(qsocket_t *sock, const sizebuf_t *data)
{
    byte *buffer;
    int *bufferLength;

    if (!sock->driverdata)
	return -1;

    bufferLength = &((qsocket_t *)sock->driverdata)->receiveMessageLength;

    if ((*bufferLength + data->cursize + sizeof(byte) + sizeof(short)) > NET_MAXMESSAGE)
	return 0;

    buffer = ((qsocket_t *)sock->driverdata)->receiveMessage + *bufferLength;

    // message type
    *buffer++ = 2;

    // length
    *buffer++ = (data->cursize >>  0) & 0xff;
    *buffer++ = (data->cursize >>  8) & 0xff;
    *buffer++ = (data->cursize >> 16) & 0xff;

    // message
    memcpy(buffer, data->data, data->cursize);
    *bufferLength = IntAlign(*bufferLength + data->cursize + 4);
    return 1;
}


qboolean
Loop_CanSendMessage(qsocket_t *sock)
{
    if (!sock->driverdata)
	return false;
    return sock->canSend;
}


qboolean
Loop_CanSendUnreliableMessage(qsocket_t *sock)
{
    return true;
}


void
Loop_Close(qsocket_t *sock)
{
    if (sock->driverdata)
	((qsocket_t *)sock->driverdata)->driverdata = NULL;
    sock->receiveMessageLength = 0;
    sock->sendMessageLength = 0;
    sock->canSend = true;
    if (sock == loop_client)
	loop_client = NULL;
    else
	loop_server = NULL;
}

int
Loop_GetDefaultMTU(void)
{
    /*
     * The loop driver can send the maximum message size in one packet
     */
    return MAX_MSGLEN;
}
