#!/bin/sh
set -e

typ=ed25519
confd="$HOME/.ssh"
cmds="gen pub list ls"

gen() {
  name=${1:-$(date -u +%Y%m%d%H%M%S)}
  ssh-keygen -t "${typ}" -f "${confd}/$name"
}

pub() {
  name="${1:-id_ed25519}"
  test -e "${confd}/${name}.pub" || return 1
  cat "${confd}/${name}.pub"
}

list() {
  while read -r line; do
    line=${line##*/}
    echo "${line%.pub}"
  done <<EOF
$(ls -1 "${confd}"/*.pub)
EOF
}

# ---------------------- bash completion context ---------------------

# add `complete -S sshkey sshkey` to bashrc

if test -n "${COMP_LINE}"; then
  pre="${COMP_LINE##* }"
  for c in ${cmds:+${cmds} $(list)}; do
    test -z "${pre}" -o "${c}" != "${c#${pre}}" && echo "$c"
  done
  exit
fi

# ------------------------------- main -------------------------------

cmd="$1"
test $# -gt 0 && shift

case "$cmd" in
pub) pub "$@" ;;
gen) gen "$@" ;;
ls | list) list "$@" ;;
*) pub "$@" ;;
esac