#include <stdlib.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif
#include "SDL.h"
#include "SDL_net.h"
#include "tcptimesync.h"

#define DO_BUSY

int main(int argc, char **argv)
{
	IPaddress ip,*remoteip;
	TCPsocket server=NULL,client=NULL;
	Uint32 ipaddr,now,last;
	float lag;
	Uint16 port;
	SyncPacket sp;
	int done;
	int minoff=5; /*that's + or - */
	
	/* check our commandline */
	if(argc<2)
	{
		printf("%s port [minoff]\n",argv[0]);
		exit(0);
	}
	
	/* initialize SDL */
	if(SDL_Init(0)==-1)
	{
		printf("SDL_Init: %s\n",SDL_GetError());
		exit(1);
	}

	/* initialize SDL_net */
	if(SDLNet_Init()==-1)
	{
		printf("SDLNet_Init: %s\n",SDLNet_GetError());
		exit(2);
	}

	/* get the port from the commandline */
	port=(Uint16) strtol(argv[1],NULL,0);

	/* get the minoff from the commandline */
	if(argc>2)
		minoff=strtol(argv[2],NULL,0);

	/* Resolve the argument into an IPaddress type */
	if(SDLNet_ResolveHost(&ip,NULL,port)==-1)
	{
		printf("SDLNet_ResolveHost: %s\n",SDLNet_GetError());
		exit(3);
	}

	/* open the server socket */
	server=SDLNet_TCP_Open(&ip);
	if(!server)
	{
		printf("SDLNet_TCP_Open: %s\n",SDLNet_GetError());
		exit(4);
	}

	while(1)
	{
		client=NULL;
		while(!client)
		{ /* no connection accepted */
			client=SDLNet_TCP_Accept(server);
			if(!client)
				SDL_Delay(100); /*sleep 1/10th of a second */
		}
		
		/* get the clients IP and port number */
		remoteip=SDLNet_TCP_GetPeerAddress(client);
		if(!remoteip)
		{
			printf("SDLNet_TCP_GetPeerAddress: %s\n",SDLNet_GetError());
			SDLNet_TCP_Close(client);
			continue;
		}

		/* print out the clients IP and port number */
		ipaddr=SDL_SwapBE32(remoteip->host);
		printf("Accepted a connection from %d.%d.%d.%d port %hu\n",
				ipaddr>>24,
				(ipaddr>>16)&0xff,
				(ipaddr>>8)&0xff,
				ipaddr&0xff,
				remoteip->port);

		done=0;
		lag=0;
		sp.type=0;
		sp.data.u.s=SDL_GetTicks();
		sendSyncPacket(client,&sp);
		now=SDL_GetTicks();
		while(!done)
		{
			last=now;
			recvSyncPacket(client,&sp);
			now=SDL_GetTicks();
			lag=(now-last)/2.0f;
			
			printSyncPacket(&sp);
			switch(sp.type)
			{
				case 0:
					sp.type=1;
					sp.data.u.s=SDL_GetTicks()+(Uint32) lag;
					sendSyncPacket(client,&sp);
					break;
				case 1:
					sp.type=2;
				case 2:
					sp.data.s.c=now-(Uint32) lag-sp.data.u.c;
					if(sp.data.s.c<minoff && sp.data.s.c>-minoff)
						/* too strict!
							&& sp.data.s.s<minoff && sp.data.s.s>-minoff)
						*/
					{
						sp.type=3;
						sp.data.u.s=SDL_GetTicks()+(Uint32) lag+minoff*100;
					}
					else
						sp.data.u.s=SDL_GetTicks()+(Uint32) lag;
					sendSyncPacket(client,&sp);
					if(sp.type==3)
					{
						printf("wait until %u\n",sp.data.u.s);
#ifdef DO_BUSY
						while(SDL_GetTicks()<sp.data.u.s);
#else
						SDL_Delay(sp.data.u.s-SDL_GetTicks());
#endif
						printf("TIME = %u\n",SDL_GetTicks());
						done=1;
					}
					break;
				default:
					done=1;
					break;
			}
			printf("now=%u (lag=%.2f)\n",now,lag);
			sp.type=10;
		}

		SDLNet_TCP_Close(client);
	}

	SDLNet_TCP_Close(server);
	
	/* shutdown SDL_net */
	SDLNet_Quit();

	/* shutdown SDL */
	SDL_Quit();

	return(0);
}