#include <stdio.h>
#include <unistd.h>
#include <arpa/inet.h>

#include "compiler.h"

#include "icmp.h"
#include "icmp_types.h"
#include "internal/ping/output.h"

// TODO: CLEAN THIS FILE !
/* Forward declarations */
static void			output_frag_needed(const char *from, uint16_t seq,
						uint16_t next_mtu);
static const char	*error_msg_for(const icmp_reply_t *reply);
/* -------------------- */

void
ping_output_error(const icmp_reply_t *reply,
		const icmp_offending_packet_t *offending,
		uint16_t seq, __unused const struct ping_config *config)
{
	char	from_str[INET_ADDRSTRLEN];

	inet_ntop(AF_INET, &reply->from, from_str, sizeof(from_str));
	if (ICMP_TYPE_DEST_UNREACHABLE == reply->type
			&& ICMP_CODE_FRAG_NEEDED == reply->code)
		output_frag_needed(from_str, seq, offending->next_mtu);
	else
		dprintf(STDERR_FILENO, "From %s: icmp_seq=%u %s\n",
				from_str, (unsigned int)seq, error_msg_for(reply));
}

static void
output_frag_needed(const char *from, uint16_t seq, uint16_t next_mtu)
{
	if (next_mtu > 0)
		dprintf(STDERR_FILENO,
				"From %s: icmp_seq=%u Frag needed and DF set (mtu = %u)\n",
				from, (unsigned int)seq, (unsigned int)next_mtu);
	else
		dprintf(STDERR_FILENO,
				"From %s: icmp_seq=%u Frag needed and DF set (mtu unknown)\n",
				from, (unsigned int)seq);
}

static const char *
error_msg_for(const icmp_reply_t *reply)
{
	static const struct s_error_entry
	{
		uint8_t		type;
		uint8_t		code;
		const char	*msg;
	} error_table[] = {
		{
			ICMP_TYPE_TIME_EXCEEDED, ICMP_CODE_TTL_EXCEEDED,
			"Time to live exceeded"
		},
		{
			ICMP_TYPE_TIME_EXCEEDED, ICMP_CODE_FRAG_REASM_EXCEEDED,
			"Frag reassembly time exceeded"
		},
		{
			ICMP_TYPE_DEST_UNREACHABLE, ICMP_CODE_NET_UNREACHABLE,
			"Destination Net Unreachable"
		},
		{
			ICMP_TYPE_DEST_UNREACHABLE, ICMP_CODE_HOST_UNREACHABLE,
			"Destination Host Unreachable"
		},
		{
			ICMP_TYPE_DEST_UNREACHABLE, ICMP_CODE_PROTOCOL_UNREACHABLE,
			"Destination Protocol Unreachable"
		},
		{
			ICMP_TYPE_DEST_UNREACHABLE, ICMP_CODE_PORT_UNREACHABLE,
			"Destination Port Unreachable"
		},
	};
	const struct s_error_entry	*entry;

	STATIC_ARRAY_FOREACH(error_table, entry)
	{
		if (entry->type == reply->type && entry->code == reply->code)
			return (entry->msg);
	}
	return ("Unknown ICMP error");
}