-define(TABLE, 1).

%% sys/types.h
-define(U_CHAR, 8/little-unsigned-integer).
-define(U_SHORT, 16/little-unsigned-integer).
-define(U_LONG, 64/little-unsigned-integer).
-define(INT, 32/little-signed-integer).
-define(PID_T, ?INT).
-define(UINT8, 8/little-unsigned-integer).
-define(UINT16, 16/little-unsigned-integer).
-define(UINT32, 32/little-unsigned-integer).
-define(UINT64, 64/little-unsigned-integer).

%% usr/include/sys/socket.h
-define(AF_UNSPEC, 0).
-define(AF_INET, 2).
-define(AF_LINK, 18).
-define(AF_INET6, 30).
-define(SOCK_RAW, 3).
-define(PF_ROUTE, 17).

%% Constants and structs are mostly defined in `net/route.h`.
%% /Library/Developer/CommandLineTools/SDKs/MacOSX12.0.sdk/usr/include/net/route.h

-define(RTM_VERSION, 5).

%% PF_ROUTE messages types
-define(RTM_ADD, 1).
-define(RTM_DELETE, 2).
-define(RTM_CHANGE, 3).
-define(RTM_GET, 4).
-define(RTM_REDIRECT, 6).
-define(RTM_MISS, 7).
-define(RTM_RESOLVE, 16#b).
-define(RTM_NEWADDR, 16#c).
-define(RTM_DELADDR, 16#d).
-define(RTM_IFINFO, 16#e).
-define(RTM_NEWMADDR, 16#f).
-define(RTM_DELMADDR, 16#10).
-define(RTM_IFINFO2, 16#12).
-define(RTM_NEWMADDR2, 16#13).
-define(RTM_GET2, 16#14).
-define(RTM, #{
               ?RTM_ADD => add,
               ?RTM_DELETE => delete,
               ?RTM_CHANGE => change,
               ?RTM_GET => get,
               ?RTM_REDIRECT => redirect,
               ?RTM_MISS => miss,
               ?RTM_RESOLVE => resolve,
               ?RTM_NEWADDR => newaddr,
               ?RTM_DELADDR => deladdr,
               ?RTM_IFINFO => ifinfo,
               ?RTM_NEWMADDR => newmaddr,
               ?RTM_DELMADDR => delmaddr,
               ?RTM_IFINFO2 => ifinfo2,
               ?RTM_NEWMADDR2 => newmaddr2,
               ?RTM_GET2 => get2
              }).

%% Bitmask values for flags
-define(RTF_UP, 1).
-define(RTF_GATEWAY, 2).
-define(RTF_HOST, 4).
-define(RTF_REJECT, 8).
-define(RTF_DYNAMIC, 16#10).
-define(RTF_MODIFIED, 16#20).
-define(RTF_DONE, 16#40).
-define(RTF_DELCLONE, 16#80).
-define(RTF_CLONING, 16#100).
-define(RTF_XRESOLVE, 16#200).
-define(RTF_LLDATA, 16#400).
-define(RTF_STATIC, 16#800).
-define(RTF_BLACKHOLE, 16#1000).
-define(RTF_NOIFREF, 16#2000).
-define(RTF_PROTO2, 16#4000).
-define(RTF_PROTO1, 16#8000).
-define(RTF_PRCLONING, 16#10000).
-define(RTF_WASCLONED, 16#20000).
-define(RTF_PROTO3, 16#40000).
-define(RTF_PINNED, 16#100000).
-define(RTF_LOCAL, 16#200000).
-define(RTF_BROADCAST, 16#400000).
-define(RTF_MULTICAST, 16#800000).
-define(RTF_IFSCOPE, 16#1000000).
-define(RTF_CONDEMNED, 16#2000000).
-define(RTF_IFREF, 16#4000000).
-define(RTF_PROXY, 16#8000000).
-define(RTF_ROUTER, 16#10000000).
-define(RTF_DEAD, 16#20000000).
-define(RTF_GLOBAL, 16#40000000).
-define(RTF, [{?RTF_UP, up}, {?RTF_GATEWAY, gateway}, {?RTF_HOST, host}, {?RTF_REJECT, reject},
             {?RTF_DYNAMIC, dynamic}, {?RTF_MODIFIED, modified}, {?RTF_DONE, done}, {?RTF_DELCLONE, delclone},
              {?RTF_CLONING, cloning}, {?RTF_XRESOLVE, xresolve}, {?RTF_LLDATA, lldata}, {?RTF_STATIC, static},
              {?RTF_BLACKHOLE, blackhole}, {?RTF_NOIFREF, noifref}, {?RTF_PROTO2, proto2}, {?RTF_PROTO1, proto1},
              {?RTF_PRCLONING, prcloning}, {?RTF_WASCLONED, wascloned}, {?RTF_PROTO3, proto3}, {?RTF_PINNED, pinned},
              {?RTF_LOCAL, local}, {?RTF_BROADCAST, broadcast}, {?RTF_MULTICAST, multicast}, {?RTF_IFSCOPE, ifscope},
              {?RTF_CONDEMNED, condemned}, {?RTF_IFREF, ifref}, {?RTF_PROXY, proxy}, {?RTF_ROUTER, router},
              {?RTF_DEAD, dead}, {?RTF_GLOBAL, global}]).

%% Bitmask values, rtm_inits and rtm_locks
-define(RTV_MTU, 1).
-define(RTV_HOPCOUNT, 2).
-define(RTV_EXPIRE, 4).
-define(RTV_RPIPE, 8).
-define(RTV_SPIPE, 16#10).
-define(RTV_SSTHRESH, 16#20).
-define(RTV_RTT, 16#40).
-define(RTV_RTTVAR, 16#80).
-define(RTV, [{?RTV_MTU, mtu}, {?RTV_HOPCOUNT, hopcount}, {?RTV_EXPIRE, expire}, {?RTV_RPIPE, recvpipe}, {?RTV_SPIPE, sendpipe},
              {?RTV_SSTHRESH, ssthresh}, {?RTV_RTT, rtt}, {?RTV_RTTVAR, rttvar}]).

%% Bitmask values for rtm_addrs
-define(RTA_DST, 1). % destination sockaddr present
-define(RTA_GATEWAY, 2). % gateway sockaddr present
-define(RTA_NETMASK, 4). % netmask sockaddr present
-define(RTA_GENMASK, 8). % cloning mask sockaddr present
-define(RTA_IFP, 16#10). % interface name sockaddr present
-define(RTA_IFA, 16#20). % interface addr sockaddr present
-define(RTA_AUTHOR, 16#40). % sockaddr for addr of redirect
-define(RTA_BRD, 16#80). % for NEWADDR, broadcast or p-p dest addr
-define(RTA, [{?RTA_DST, destination}, {?RTA_GATEWAY, gateway}, {?RTA_NETMASK, netmask},
                          {?RTA_GENMASK, genmask}, {?RTA_IFP, ifp}, {?RTA_IFA, ifa},
                          {?RTA_AUTHOR, author}, {?RTA_BRD, brd}]).

-record(macos_rt, {type, % Message type, atom
                   flags, % Route flags
                   addrs, % Addresses list
                   pid, % Originating pid
                   seq, % user data
                   errno, % error number
                   refcount, % reference count (msghdr2)
                   parent_flags, % flags of the parent route (msghdr2)
                   use, % documented as: "from rentry"

                   % Metrics
                   metrics_init, % metrics that are initializing
                   metrics_lock, % metrics that are locked
                   mtu, % mtu
                   hopcount, % max hops expected
                   expire, % lifetime for route
                   recvpipe, % inbound delay-bandwith product
                   sendpipe, % outbound delay-bandwith product
                   ssthresh, % outbound gateway buffer limit
                   rtt, % estimated round trip time
                   rttvar, % estimated rtt variance
                   pksent, % packets sent using this route
                   state, % route state
                   filler, % "will be used for TCP's peer-MSS cache"

                   % Addresses
                   destination, % Destination
                   gateway, % Gateway
                   netmask, % netmask
                   clonemask, % (C: genmask) cloning mask
                   ifp, % interface name
                   ifp_index, % (C: index) Scope for associated ifp, if present
                   ifa, % interface address
                   author, % author of redirect
                   brd % (only for type=newaddr) broadcast or p-p destination address
}).

-record(macos_link, {index, % system index for interface
                     type, % interface type
                     name, % interface name
                     address, % link level address
                     selector % link layer selector,
                    }).

%% net/if.h

-define(IFF_UP, 16#1).
-define(IFF_BROADCAST, 16#2).
-define(IFF_DEBUG, 16#4).
-define(IFF_LOOPBACK, 16#8).
-define(IFF_POINTOPOINT, 16#10).
-define(IFF_NOTRAILERS, 16#20).
-define(IFF_RUNNING, 16#40).
-define(IFF_NOARP, 16#80).
-define(IFF_PROMISC, 16#100).
-define(IFF_ALLMULTI, 16#200).
-define(IFF_OACTIVE, 16#400).
-define(IFF_SIMPLEX, 16#800).
-define(IFF_LINK0, 16#1000).
-define(IFF_LINK1, 16#2000).
-define(IFF_LINK2, 16#4000).
-define(IFF_MULTICAST, 16#8000).
-define(IFF, [{?IFF_UP, up}, {?IFF_BROADCAST, broadcast}, {?IFF_DEBUG, debug}, {?IFF_LOOPBACK, loopback}, {?IFF_POINTOPOINT, pointopoint},
             {?IFF_NOTRAILERS, notrailers}, {?IFF_RUNNING, running}, {?IFF_NOARP, noarp}, {?IFF_PROMISC, promisc}, {?IFF_ALLMULTI, allmulti},
             {?IFF_OACTIVE, oactive}, {?IFF_SIMPLEX, simplex}, {?IFF_LINK0, link0}, {?IFF_LINK1, link1}, {?IFF_LINK2, link2}, {?IFF_MULTICAST, multicast}]).

-record(macos_if, {type, flags, addrs, index, typelen, physical, addrlen, hdrlen, recvquota, xmitquota, mtu, metric, baudrate,
                  ipackets, ierrors, opackets, oerrors, ibytes, obytes, imcasts, omcasts, iqdrops, noproto, recvtiming, xmittiming}).

-record(macos_ifa, {type, flags, addrs, index, metric, netmask, ifp, ifa}).

-record(macos_ifma, {type, flags, addrs, index, refcount, netmask, ifp, ifa}).