#include <criterion/criterion.h>
#include <string.h>
#include "icmp.h"

static icmp_reply_t
make_echo_reply(uint8_t type, uint16_t id, uint16_t seq, uint8_t *buffer)
{
	icmp_reply_t reply;

	memset(&reply, 0, sizeof(reply));
	memset(buffer, 0, 8);
	reply.type = type;
	reply.code = 0;
	buffer[0] = type;
	buffer[1] = 0;
	buffer[2] = 0;
	buffer[3] = 0;
	buffer[4] = (id >> 8) & 0xFF;
	buffer[5] = id & 0xFF;
	buffer[6] = (seq >> 8) & 0xFF;
	buffer[7] = seq & 0xFF;
	reply.ip_payload = buffer;
	reply.ip_payload_len = 8;
	return reply;
}

Test(extract_echo, echo_reply_type_0)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(0, 0x1234, 0x5678, buffer);
	uint16_t id;
	uint16_t seq;
	int ret;

	ret = icmp_reply_id_seq(&reply, &id, &seq);
	cr_assert_eq(ret, 0);
	cr_assert_eq(id, 0x1234);
	cr_assert_eq(seq, 0x5678);
}

Test(extract_echo, echo_request_type_8)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(8, 0xABCD, 0xEF01, buffer);
	uint16_t id;
	uint16_t seq;
	int ret;

	ret = icmp_reply_id_seq(&reply, &id, &seq);
	cr_assert_eq(ret, 0);
	cr_assert_eq(id, 0xABCD);
	cr_assert_eq(seq, 0xEF01);
}

Test(extract_echo, non_echo_type_returns_error)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(3, 0x1234, 0x5678, buffer);
	uint16_t id = 0xFFFF;
	uint16_t seq = 0xFFFF;
	int ret;

	ret = icmp_reply_id_seq(&reply, &id, &seq);
	cr_assert_eq(ret, -1);
	cr_assert_eq(id, 0xFFFF, "id should be unchanged on error");
	cr_assert_eq(seq, 0xFFFF, "seq should be unchanged on error");
}

Test(extract_echo, null_reply_returns_error)
{
	uint16_t id;
	uint16_t seq;
	int ret;

	ret = icmp_reply_id_seq(NULL, &id, &seq);
	cr_assert_eq(ret, -1);
}

Test(extract_echo, null_id_allowed)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(0, 0x1234, 0x5678, buffer);
	uint16_t seq;
	int ret;

	ret = icmp_reply_id_seq(&reply, NULL, &seq);
	cr_assert_eq(ret, 0);
	cr_assert_eq(seq, 0x5678);
}

Test(extract_echo, null_seq_allowed)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(0, 0x1234, 0x5678, buffer);
	uint16_t id;
	int ret;

	ret = icmp_reply_id_seq(&reply, &id, NULL);
	cr_assert_eq(ret, 0);
	cr_assert_eq(id, 0x1234);
}

Test(extract_echo, both_null_allowed)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(0, 0x1234, 0x5678, buffer);
	int ret;

	ret = icmp_reply_id_seq(&reply, NULL, NULL);
	cr_assert_eq(ret, 0);
}

Test(extract_echo, payload_too_short_returns_error)
{
	uint8_t buffer[8];
	icmp_reply_t reply = make_echo_reply(0, 0x1234, 0x5678, buffer);
	uint16_t id;
	uint16_t seq;
	int ret;

	reply.ip_payload_len = 7;
	ret = icmp_reply_id_seq(&reply, &id, &seq);
	cr_assert_eq(ret, -1);
}

Test(extract_echo, null_ip_payload_returns_error)
{
	icmp_reply_t reply;
	uint16_t id;
	uint16_t seq;
	int ret;

	memset(&reply, 0, sizeof(reply));
	reply.type = 0;
	reply.ip_payload = NULL;
	reply.ip_payload_len = 8;
	ret = icmp_reply_id_seq(&reply, &id, &seq);
	cr_assert_eq(ret, -1);
}