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use alienfile;

# Net-SNMP is built deliberately minimal and from a pinned source tarball; we never
# probe for / use a system copy. This forces a share (source) build, equivalent to
# the legacy alien_check_installed_version returning nothing.
probe sub { 'share' };

share {
  # Canonical raw URL serves the tarball directly (no GitHub blob-page redirects).
  # The netdisco mirror is byte-for-byte identical to the official Net-SNMP
  # release on SourceForge.
  start_url 'https://raw.githubusercontent.com/netdisco/upstream-sources/master/net-snmp/net-snmp-5.9.5.2.tar.gz';

  plugin 'Download';   # https fetch requires a TLS-capable fetcher (Net::SSLeay/IO::Socket::SSL or curl/wget)

  # Verify integrity independent of host. We pin SHA256 (SourceForge publishes only
  # SHA1, which is collision-broken and too weak to trust a third-party mirror against).
  # On every Net-SNMP version bump, regenerate this line with:
  #   maintainer/update-netsnmp-digest --version <x.y.z> --sha1 <sha1-from-sourceforge>
  # That verifies the tarball against SourceForge's published SHA1 (the human trust
  # anchor), computes this SHA256 from the verified file, and confirms the netdisco
  # mirror is byte-identical.
  digest 'SHA256', '16707719f833184a4b72835dac359ae188123b06b5e42817c00790d7dc1384bf';

  plugin 'Extract' => 'tar.gz';

  # Inject `use Alien::SNMP;` into the bundled Perl module before it is built, so the
  # installed SNMP.pm pulls in this Alien at use-time to locate the dynamic libnetsnmp.
  # (Was inc/My/AlienPatch.pm.)  cwd here is the extracted source root.
  patch sub {
    my $file = 'perl/SNMP/SNMP.pm';
    open my $in, '<', $file or die "can't read $file: $!";
    my @lines = <$in>;
    close $in;
    for my $line (@lines) {
      if ($line =~ /use warnings;/) {
        $line .= "\nuse Alien::SNMP;\n";
        last;
      }
    }
    open my $out, '>', $file or die "can't write $file: $!";
    print {$out} @lines;
    close $out;
  };

  # Provides %{configure} (adds --prefix and --with-pic) and %{make}.  We keep the
  # plugin's default DESTDIR staging (meta destdir=1) so %{configure} uses
  # --prefix=<final runtime share dir>.  That final prefix is what net-snmp bakes into
  # the bundled SNMP XS module's rpath, so the installed SNMP.so finds *our* libnetsnmp
  # in the installed share (not a system copy or the temporary build dir).
  plugin 'Build::Autoconf';

  build [
    # Same configure flags as the legacy $conf_cmd, minus --with-pic and --prefix
    # which the Autoconf plugin supplies via %{configure}.  --with-perl-modules builds
    # the bundled SNMP XS module against the just-built libnetsnmp.
    '%{configure}'
      . ' --disable-agent --disable-scripts --disable-mibs'
      . ' --enable-ipv6 --with-mibs=""'
      . ' --with-perl-modules --disable-embedded-perl'
      . ' --disable-manuals --enable-blumenthal-aes --with-defaults',
    '%{make}',
    # Net-SNMP ignores the DESTDIR *environment* variable Alien::Build sets, so pass it
    # explicitly (its Makefile honors $(DESTDIR)).  This stages everything -- the C
    # library/headers/bin AND the bundled Perl modules -- under $DESTDIR with the final
    # install paths baked in (SNMP.so's rpath points at the installed share).  Gather
    # then relocates $DESTDIR/<prefix> (the C library) into the share dir.
    '%{make} install DESTDIR=$DESTDIR',
    # The Perl modules need to live in the real perl site_lib (that is how downstream
    # `use SNMP;` works), but the line above staged them under $DESTDIR.  Copy the staged
    # files into the real filesystem, skipping the Alien share itself (Gather installs
    # that via blib, so copying it here would double-install / pollute).  We use a small
    # File::Find copier rather than `tar -C / -x` because tar aborts trying to chmod
    # pre-existing top-level dirs (/, /home, ...) it does not own; this creates parent