#include <stdio.h>
#include <limits.h>
#include <time.h>
#include <sys/time.h>
#include <nftables/libnftables.h>

void timespec_diff(struct timespec *a, const struct timespec *b)
{
	a->tv_sec -= b->tv_sec;
	if (a->tv_nsec < b->tv_nsec) {
		a->tv_nsec += 1e9 - b->tv_nsec;
		a->tv_sec--;
	} else {
		a->tv_nsec -= b->tv_nsec;
	}
}

static const char *create =
"add table inet slew {"
"       flags owner;"
"	map tunmap-pre { typeof ip daddr . @ih,32,32 : verdict; };"
"	map tunmap-post { typeof meta mark : verdict; };"
"	chain pre { type filter hook prerouting priority -300; policy accept;"
"	        udp dport 2152 ip daddr . @ih,32,32 vmap @tunmap-pre;"
"       };"
"	chain post { type filter hook postrouting priority 400; policy accept;"
"		meta mark vmap @tunmap-post;"
"	};"
"}"
;

static struct nft_ctx *nft_ctx;

int main(void) {
	nft_ctx = nft_ctx_new(NFT_CTX_DEFAULT);

	if (!nft_ctx) {
		printf("cannot create nft_ctx\n");
		return 1;
	}

	if (nft_run_cmd_from_buffer(nft_ctx, create)) {
		printf("cannot init table\n");
		return 1;
	}

	char cmd[1024];

	const unsigned int n = 5000;

	struct timespec last_start;
	struct timespec last_diff;

	struct timespec start;
	struct timespec now;

	clock_gettime(CLOCK_MONOTONIC, &last_start);
	int count_since_last = 0;

	for (unsigned int i = 1; i <= n; i++) {
		snprintf(cmd, sizeof(cmd),
			 "add chain inet slew tunmap-pre-%u;\n"
			 "add rule inet slew tunmap-pre-%u"
			 " ip daddr set 127.0.1.1"
			 " meta mark set %u counter accept;\n"
			 "add chain inet slew tunmap-post-%u;\n"
			 "add rule inet slew tunmap-post-%u"
			 " ip saddr set 127.0.2.1"
			 " udp sport set 2152"
			 " @ih,32,32 set 0x%x"
			 " counter accept;\n"
			 "add element inet slew tunmap-pre { "
			 "127.0.1.1 . 0x%x : jump tunmap-pre-%u };\n"
			 "add element inet slew tunmap-post { %u : jump tunmap-post-%u };\n",
			 i, i, i, i, i,
			 UINT_MAX - i,
			 i,
			 i, i, i);

		bool show_time = ((i & 0x7f) == 0) || (i == 1) || (i == n) || (i == n - 1);

		if (show_time)
			clock_gettime(CLOCK_MONOTONIC, &start);

		if (nft_run_cmd_from_buffer(nft_ctx, cmd)) {
			printf("failed on %u\n", i);
			return 1;
		}

		count_since_last++;
		if (show_time) {
			clock_gettime(CLOCK_MONOTONIC, &now);

			last_diff = now;
			timespec_diff(&last_diff, &last_start);
			last_start = now;

			timespec_diff(&now, &start);
			printf("created idx %4d in %8u ns   (%d in %u ms)\n",
			       i, now.tv_nsec,
			       count_since_last, last_diff.tv_nsec / 1000000 + last_diff.tv_sec * 1000);
			fflush(stdout);
			count_since_last = 0;
			clock_gettime(CLOCK_MONOTONIC, &last_start);
		}
	}

	for (unsigned int i = 1; i <= n; i++) {
		snprintf(cmd, sizeof(cmd),
			 "delete element inet slew tunmap-pre { 127.0.1.1 . 0x%x };\n"
			 "delete element inet slew tunmap-post { %u };\n"
			 "delete chain inet slew tunmap-pre-%u;\n"
			 "delete chain inet slew tunmap-post-%u;\n",
			 i, i, i, i);

		bool show_time = ((i & 0x7f) == 0) || (i == 1) || (i == n) || (i == n - 1);

		if (show_time)
			clock_gettime(CLOCK_MONOTONIC, &start);

		if (nft_run_cmd_from_buffer(nft_ctx, cmd)) {
			printf("failed on deleting %u\n", i);
			return 1;
		}

		count_since_last++;
		if (show_time) {
			clock_gettime(CLOCK_MONOTONIC, &now);

			last_diff = now;
			timespec_diff(&last_diff, &last_start);
			last_start = now;

			timespec_diff(&now, &start);
			printf("deleted idx %4d in %8u ns   (%d in %u ms)\n",
			       i, now.tv_nsec,
			       count_since_last, last_diff.tv_nsec / 1000000 + last_diff.tv_sec * 1000);
			fflush(stdout);
			count_since_last = 0;
			clock_gettime(CLOCK_MONOTONIC, &last_start);
		}
	}

	nft_ctx_free(nft_ctx);

	return 0;
}