#compdef losetup

local cyphers
cyphers=( /proc/crypto/cipher/*(N:t) )
cyphers="${cyphers[@]%-*}"

_arguments -S \
  '(- 2)'{--delete,--detach,-d}'[detach from specified loop device]' \
  '(-d --delete --detach -e --encryption)'{-e,--encryption}"+[enable encryption]:cypher:( $cyphers )" \
  '(-d --delete --detach -o --offset)'{-o,--offset}'+[specify data start is offset]:offset (bytes)' \
  '(-d --delete --detach -p --pass-fd)'{-p,--pass-fd}'+[read passphrase from specified file descriptor]:file descriptor:_file_descriptors' \
  '(-d --delete --detach -k --keybits)'{-k,--keybits}'+[set the number of bits to use in key]:key size:(64 128 160 192 256)' \
  '1:device:_files -g "loop*(-.)"' \
  '(-d --delete --detach)2:file:_files'