# bash completion for duser
# shellcheck shell=bash
_duser_users() {
	local min max
	min=$(awk '$1 == "UID_MIN" { print $2 }' /etc/login.defs 2>/dev/null)
	max=$(awk '$1 == "UID_MAX" { print $2 }' /etc/login.defs 2>/dev/null)
	getent passwd | awk -F: -v min="${min:-1000}" -v max="${max:-60000}" '$3 >= min && $3 <= max { print $1 }'
}

_duser() {
	local cur=${COMP_WORDS[COMP_CWORD]} cmd=${COMP_WORDS[1]:-}
	if ((COMP_CWORD == 1)); then
		mapfile -t COMPREPLY < <(compgen -W "list add del passwd lock unlock key groups help" -- "$cur")
		return
	fi
	case $cmd in
	add)
		if [[ ${COMP_WORDS[COMP_CWORD - 1]} == --key ]]; then
			mapfile -t COMPREPLY < <(compgen -f -- "$cur")
		else
			mapfile -t COMPREPLY < <(compgen -W "--admin --key --no-password --password-stdin" -- "$cur")
		fi
		;;
	del | passwd | lock | unlock | key | groups)
		if ((COMP_CWORD == 2)); then
			mapfile -t COMPREPLY < <(compgen -W "$(_duser_users)" -- "$cur")
		elif [[ $cmd == del ]]; then
			mapfile -t COMPREPLY < <(compgen -W "--home" -- "$cur")
		elif [[ $cmd == key ]] && ((COMP_CWORD == 3)); then
			mapfile -t COMPREPLY < <(compgen -W "list add rm" -- "$cur")
		elif [[ $cmd == key && ${COMP_WORDS[3]} == add ]]; then
			mapfile -t COMPREPLY < <(compgen -f -- "$cur")
		elif [[ $cmd == groups ]]; then
			# +GROUP and -GROUP
			local sign=${cur:0:1}
			[[ $sign == [+-] ]] || sign=+
			mapfile -t COMPREPLY < <(compgen -P "$sign" -W "$(getent group | cut -d: -f1)" -- "${cur#[+-]}")
		fi
		;;
	esac
}
complete -F _duser duser