#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "../port/error.h"

#include "ip.h"

enum {
	Qdir,
	Qstats,
	Qctl,
};

enum {
	GEMProtoIP4,
	GEMProtoIP6,
	GEMProtoTCP,
	GEMProtoUDP,
	GEMProtoICMP,
}

static void			 GEMparse(char *, long);
static char 		*GEMstats(void);
static void			 GEMgetip(uchar *, uchar *, uint *, uint *);

static ulong		GEMdb;
static ulong		GEMsize;
static char			*ruleset;



static Dirtab GEMtab[] = {
	".",		{ Qdir, 0, QTDIR },	0,	0555,
	"stats",	{ Qstats, 0 },		0,	0600,
	"ctl",		{ Qctl, 0 },		0,	0600,
};

static Chan *
GEMattach(char *spec)
{
	return devattach('ƒ', spec);
}

static Walkqid *
GEMwalk(Chan *c, Chan *nc, char **name, int nname)
{
	return devwalk(c, nc, name, nname, GEMtab, nelem(GEMtab), devgen);
}

static int
GEMstat(Chan *c, uchar *dp, int n)
{
	return devstat(c, dp, n, GEMtab, nelem(GEMtab), devgen);
}

static Chan *
GEMopen(Chan *c, int mode)
{
	return devopen(c, mode, GEMtab, nelem(GEMtab), devgen);
}

static long
GEMread(Chan *c, void *a, long n, vlong off)
{
	switch((ulong)c->qid.path) {
	case Qdir:
		return devdirread(c, a, n, GEMtab, nelem(GEMtab), devgen);
	case Qctl:
		return readstr(off, a, n, ruleset);
	case Qstats:
		return readstr(off, a, n, GEMstats());
	default:
		n = 0;
		break;
	}

	return n;
}

static long
GEMwrite(Chan *c, void *a, long n, vlong off)
{
	USED(off)

	switch((ulong)c->qid.path) {
	case Qctl:
		GEMparse((char *)a, n);
		break;
	default:
		error(Ebadusefd);
	}

	return n;
}

static char *
GEMstats(void)
{
	char *stats;
}

static void
GEMgetip(uchar addr1[4], uchar addr2[4], uint *l_item, uint *r_item)
{
	*l_item = nhgetl(addr1)&nhgetl(addr2);
	*r_item = *l_item + (!nhgetl(addr2));
}

/* XXX proto is always TCP on IPv4 for right now */
static int
GEMsearch(const void *iphdr, const void *protohdr, struct GEMlist *h, int ipver,
	int proto)
{
	uint arg1, arg2, i, start, end, packet[4], curlevel;
	ulong src, dst;
	GEMlevel *l, *l2;

	/*if (ipver == GEMProtoIP4) {*/
		packet[0] = nhgetl((Ip4hdr *)iphdr->src);
		packet[1] = nhgetl((Ip4hdr *)iphdr->dst);
		packet[2] = nhgets((Tcp4hdr *)protohdr->tcpsport);
		packet[3] = nhgets((Tcp4hdr *)protohdr->tcpdport);
	/*} else {
		packet[0] = nhgetl((Ip6hdr *)iphdr->src);
		packet[1] = nhgetl((Ip6hdr *)iphdr->dst);
		packet[2] = nhgetl((Tcp6hdr *)protohdr->tcpsport);
		packet[3] = nhgetl((Tcp6hdr *)protohdr->tcpdport);
	}*/

	l = l2 = h;

	for (curlevel = 0; curlevel <= GEMNumLevels; curlevel++, 
	     l2 = l + l->nextlevel) {
		start = 0;
		end = l->levelsize - 1;

		while (start != end) {
			i = (start + end) >> 1;
			arg1 = (l2)[i].lower_border;

			if (i + 1 < h->size)
				arg2 = (l2)[i + 1].lower_border
			else
				arg2 = h->levelmax[curlevel];

			if (packet[h->levels[curlevel]] < arg1)
				end = i - 1;
			else if (packet[h->levels[curlevel]] < arg2)
				start = end = i;
			else
				start = i+1;
		}

		l = &((l2->nextlevel)[start]);
	}

	return (l + l->nextlevel)[start].nextlevel;
}

Dev GEMdevtab = {
	'ƒ',
	"GEMfilter",

	devreset,
	devinit,
	GEMattach,
	GEMwalk,
	GEMstat,
	GEMopen,
	devcreate,
	GEMclose,
	GEMread,
	devbread,
	GEMwrite,
	devbwrite,	
	devremove,
	devwstat,
};