#compdef last lastb

local pattern arg args ttys
ttys=( /dev/tty*(N) /dev/pts/*(N) reboot )
ttys=( ${ttys#/dev/} )

for pattern arg in \
  '(solaris*|linux-gnu)' '-a[display hostname in last column]' \
  '((free|net|open)bsd*|darwin*|dragonfly*|linux-gnu)' '-h[limit sessions by hostname]:host:_hosts' \
  '((free|open)bsd*|linux-gnu)' '-s[report duration in seconds]' \
  '(freebsd*|openbsd*)' '-d[limit sessions to those active at snapshot time]:time ([[CC]YY][MMDD]hhmm[.SS])' \
  '((net|free|open)bsd*|darwin*|dragonfly*)' '-t[limit sessions by tty]:tty:compadd -a ttys' \
  'openbsd*' '-c[calculate total time]' \
  '^darwin*' '-f[specify account file]:file:_files' \
  '(solaris*|linux-gnu|freebsd*|openbsd*)' '-n[specify number of lines to show]:number' \
  '((open|net)bsd*|dragonfly*)' '-T[show more detailed time information including year and seconds]' \
  'netbsd*' '-x[assume file is in wtmpx(5) format]' \
  'netbsd*' '-n[show IP of remote hosts]' \
  'freebsd*' '-w[show seconds in durarion field]' \
  'freebsd*' '-y[show year in session start time]'
do
  [[ $OSTYPE = $~pattern ]] && args+=( $arg )
done

case $OSTYPE in
  netbsd*|dragonfly*)
    args+=(
      '-H[specify width for host field]:width'
      '-N[specify width for login name field]:width'
      '-L[specify width for tty field]:width'
    )
  ;;
  linux-gnu)
    args+=(
      '-R[suppress display of hostname field]'
      '-d[translate IP to hostname]'
      '-F[show full login and logout times and dates]'
      '-i[show IP of remote hosts]'
      '-o[read old-format wtmp]'
      '-t[limit sessions to those active at snapshot time]:time (YYYYMMDDhhmmss)'
      '-w[show full user and domain names]'
      '-x[display shutdown/runlevel entries]'
    )
  ;;
esac

if [[ $OSTYPE = (linux-gnu|solaris*) ]]; then
  args+=( '*:arg: _alternative "users:user:_users" "ttys:tty:compadd -a ttys"' )
else
  args+=( '*:user:_users' )
fi

_arguments -s $args