#pragma once

#include <netinet/in.h>
#include <netinet/ip.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

struct icmphdr {
    uint8_t type;
    uint8_t code;
    uint16_t checksum;
    union {
        struct {
            uint16_t id;
            uint16_t sequence;
        } echo;
        uint32_t gateway;
        struct {
            uint16_t __unused;
            uint16_t mtu;
        } frag;
    } un;
};

#define ICMP_ECHOREPLY 0
#define ICMP_DEST_UNREACH 3
#define ICMP_SOURCE_QUENCH 4
#define ICMP_REDIRECT 5
#define ICMP_ECHO 8
#define ICMP_TIME_EXCEEDED 11
#define ICMP_PARAMETERPROB 12
#define ICMP_TIMESTAMP 13
#define ICMP_TIMESTAMPREPLY 14
#define ICMP_INFO_REQUEST 15
#define ICMP_INFO_REPLY 16
#define ICMP_ADDRESS 17
#define ICMP_ADDRESSREPLY 18
#define NR_ICMP_TYPES 18

#define ICMP_NET_UNREACH 0
#define ICMP_HOST_UNREACH 1
#define ICMP_PROT_UNREACH 2
#define ICMP_PORT_UNREACH 3
#define ICMP_FRAG_NEEDED 4
#define ICMP_SR_FAILED 5
#define ICMP_NET_UNKNOWN 6
#define ICMP_HOST_UNKNOWN 7
#define ICMP_HOST_ISOLATED 8
#define ICMP_NET_ANO 9
#define ICMP_HOST_ANO 10
#define ICMP_NET_UNR_TOS 11
#define ICMP_HOST_UNR_TOS 12
#define ICMP_PKT_FILTERED 13
#define ICMP_PREC_VIOLATION 14
#define ICMP_PREC_CUTOFF 15
#define NR_ICMP_UNREACH 15

#define ICMP_REDIR_NET 0
#define ICMP_REDIR_HOST 1
#define ICMP_REDIR_NETTOS 2
#define ICMP_REDIR_HOSTTOS 3

#define ICMP_EXC_TTL 0
#define ICMP_EXC_FRAGTIME 1

struct icmp_ra_addr {
    uint32_t ira_addr;
    uint32_t ira_preference;
};

struct icmp {
    uint8_t icmp_type;
    uint8_t icmp_code;
    uint16_t icmp_cksum;
    union {
        uint8_t ih_pptr;
        struct in_addr ih_gwaddr;
        struct ih_idseq {
            uint16_t icd_id;
            uint16_t icd_seq;
        } ih_idseq;
        uint32_t ih_void;

        struct ih_pmtu {
            uint16_t ipm_void;
            uint16_t ipm_nextmtu;
        } ih_pmtu;

        struct ih_rtradv {
            uint8_t irt_num_addrs;
            uint8_t irt_wpa;
            uint16_t irt_lifetime;
        } ih_rtradv;
    } icmp_hun;
    union {
        struct {
            uint32_t its_otime;
            uint32_t its_rtime;
            uint32_t its_ttime;
        } id_ts;
        struct {
            struct ip idi_ip;
        } id_ip;
        struct icmp_ra_addr id_radv;
        uint32_t id_mask;
        uint8_t id_data[1];
    } icmp_dun;
};

#define icmp_pptr icmp_hun.ih_pptr
#define icmp_gwaddr icmp_hun.ih_gwaddr
#define icmp_id icmp_hun.ih_idseq.icd_id
#define icmp_seq icmp_hun.ih_idseq.icd_seq
#define icmp_void icmp_hun.ih_void
#define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void
#define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu
#define icmp_num_addrs icmp_hun.ih_rtradv.irt_num_addrs
#define icmp_wpa icmp_hun.ih_rtradv.irt_wpa
#define icmp_lifetime icmp_hun.ih_rtradv.irt_lifetime
#define icmp_otime icmp_dun.id_ts.its_otime
#define icmp_rtime icmp_dun.id_ts.its_rtime
#define icmp_ttime icmp_dun.id_ts.its_ttime
#define icmp_ip icmp_dun.id_ip.idi_ip
#define icmp_radv icmp_dun.id_radv
#define icmp_mask icmp_dun.id_mask
#define icmp_data icmp_dun.id_data

#define ICMP_MINLEN 8
#define ICMP_TSLEN (8 + 3 * sizeof(n_time))
#define ICMP_MASKLEN 12
#define ICMP_ADVLENMIN (8 + sizeof(struct ip) + 8)
#define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8)

#define ICMP_UNREACH 3
#define ICMP_SOURCEQUENCH 4
#define ICMP_ROUTERADVERT 9
#define ICMP_ROUTERSOLICIT 10
#define ICMP_TIMXCEED 11
#define ICMP_PARAMPROB 12
#define ICMP_TSTAMP 13
#define ICMP_TSTAMPREPLY 14
#define ICMP_IREQ 15
#define ICMP_IREQREPLY 16
#define ICMP_MASKREQ 17
#define ICMP_MASKREPLY 18
#define ICMP_MAXTYPE 18

#define ICMP_UNREACH_NET 0
#define ICMP_UNREACH_HOST 1
#define ICMP_UNREACH_PROTOCOL 2
#define ICMP_UNREACH_PORT 3
#define ICMP_UNREACH_NEEDFRAG 4
#define ICMP_UNREACH_SRCFAIL 5
#define ICMP_UNREACH_NET_UNKNOWN 6
#define ICMP_UNREACH_HOST_UNKNOWN 7
#define ICMP_UNREACH_ISOLATED 8
#define ICMP_UNREACH_NET_PROHIB 9
#define ICMP_UNREACH_HOST_PROHIB 10
#define ICMP_UNREACH_TOSNET 11
#define ICMP_UNREACH_TOSHOST 12
#define ICMP_UNREACH_FILTER_PROHIB 13
#define ICMP_UNREACH_HOST_PRECEDENCE 14
#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15

#define ICMP_REDIRECT_NET 0
#define ICMP_REDIRECT_HOST 1
#define ICMP_REDIRECT_TOSNET 2
#define ICMP_REDIRECT_TOSHOST 3

#define ICMP_TIMXCEED_INTRANS 0
#define ICMP_TIMXCEED_REASS 1

#define ICMP_PARAMPROB_OPTABSENT 1

#define ICMP_INFOTYPE(type)                                                                 \
    ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || (type) == ICMP_ROUTERADVERT ||      \
     (type) == ICMP_ROUTERSOLICIT || (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
     (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || (type) == ICMP_MASKREQ ||           \
     (type) == ICMP_MASKREPLY)

#ifdef __cplusplus
}
#endif