#compdef split gsplit

local curcontext="$curcontext" variant ret=1
local -A opt_args
local -a state line args

_pick_variant -r variant gnu=GNU $OSTYPE --version

args=(
  '-a+[generate suffixes of specified length]:length [2]' \
  '(-l -p -n)-b+[put specified size in bytes in each output file]:size (bytes)' \
  '(-b -p -n)-l+[put specified number of lines/records in each output file]:lines' \
  '1:file:_files' \
  '2: :_guard "^-*" "prefix [x]"'
)

case $variant in
  gnu)
    args=( -C
      '(H -a --suffix-length)'{-a+,--suffix-length=}'[generate suffixes of specified length]:length [2]'
      '(H)--additional-suffix=[append an additional suffix to file names]:suffix'
      '(H -b --bytes -C --line-bytes -l --lines -n --number)'{-b+,--bytes=}'[put specified size in bytes in each output file]:size (bytes)'
      '(H -b --bytes -C --line-bytes -l --lines -n --number)'{-C+,--line-bytes=}'[put whole lines/records up to size limit in each output file]:size (bytes)'
      '(H --numeric-suffixes -x --hex-suffixes)-d[use numeric suffixes starting at 0]'
      '(H -d -x --hex-suffixes)--numeric-suffixes=-[use numeric suffixes]::start value [0]'
      '(H -d --numeric-suffixes --hex-suffixes)-x[use hex suffixes starting at 0]'
      '(H -d --numeric-suffixes -x)--hex-suffixes=-[use hex suffixes]::start value [0]'
      '(H -e --elide-empty-files)'{-e,--elide-empty-files}"[don't generate empty output files with '-n']"
      '(H)--filter=[write to shell command; filename is in $FILE]:command:_cmdstring'
      '(H -b --bytes -C --line-bytes -l --lines -n --number)'{-l+,--lines=}'[put specified number of lines/records in each output file]:lines'
      '(H -b --bytes -C --line-bytes -l --lines -n --number)'{-n+,--number=}'[generate specified number of output files]:chunks:->chunks'
      '(H -t --separator)'{-t+,--separator=}'[use specified record separator instead of newline]:separator'
      '(H -u --unbuffered)'{-u,--unbuffered}"[immediately copy input to output with '-n r/...']"
      '(H)--verbose[print a diagnostic just before each output file is opened]'
      '(H)1:file:_files'
      '(H)2: :_guard "^-*" "prefix [x]"'
      + 'H'
      '(- 1 2)--help[display usage information]'
      '(- 1 2)--version[display version information]'
    )
  ;;
  (free|net)bsd*)
    args+=( '(-b -l -p)-n+[generate specified number of output files]:output files' )
  ;|
  darwin*|freebsd*)
    args+=(
      '(-b -l -n)-p+[split the file whenever a line matches specified pattern]:pattern'
    )
  ;|
  freebsd*) args+=( '-d[use numeric suffixes]' ) ;;
esac

_arguments -s -S $args && ret=0

if [[ $state = chunks ]]; then
  if [[ ! -prefix *[0-9/]* ]]; then
    _alternative 'modifiers: :_values -s/ "modifier" "l[don'\''t split lines/records]" "r[round robin distribution]"' \
      'lines: :_guard "[0-9/]#" lines' && ret=0
  else
    _message -e lines lines
  fi
fi

return ret