# -*-eselect-*-  vim: ft=eselect
# Copyright 2005-2020 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2 or later
# $

DESCRIPTION="Control which metaploit version is active"
MAINTAINER="zerochaos@pentoo.ch"

###WARNING: don't even think of using this insanity for a reference (but it works,mostly)
#base idea from kernel.eselect with --use-old from opencl.eselect
#all modified randomly until it worked, entropy is wonderful
###/WARNING

MSFPATH="/usr/lib/metasploit"

# find a list of metasploit symlink targets and sort them
find_targets() {
	local f
	for f in "${EROOT}${MSFPATH}"[[:digit:]]*; do
		[[ -d ${f} ]] && basename "${f}"
	done | LC_ALL=C sort
}

# remove the metasploit symlink
remove_symlink() {
	for i in $(qlist metasploit | grep $(canonicalise "${EROOT}${MSFPATH}")/msf)
	do
		if [ -L /usr/bin/$(echo ${i} | awk -F'/' '{print $5}') ]; then
			unlink /usr/bin/$(echo ${i} | awk -F'/' '{print $5}') || die -q "failed to unlink ${i}"
		fi
	done
	if [ -L ${EROOT}${MSFPATH} ]; then
		unlink "${EROOT}${MSFPATH}" || die -q "failed to unlink ${EROOT}${MSFPATH}"
	elif [ -e ${EROOT}${MSFPATH} ]; then
		die -q "${EROOT}${MSFPATH} exists but is not a symlink"
	fi
}

# set the metasploit symlink
set_symlink() {
	local target=$1

	if is_number "${target}"; then
		local targets=( $(find_targets) )
		target=${targets[target-1]}
	fi

	if [[ -z ${target} ]]; then
		die -q "Target \"$1\" doesn't appear to be valid!"
	elif [[ -d ${EROOT}/usr/lib/${target} ]]; then
		ln -sf "${target}" "${EROOT}${MSFPATH}"
		for i in $(qlist metasploit | grep "/usr/lib/${target}/msf")
		do
			ln -sf /usr/bin/msfloader /usr/bin/$(echo ${i} | awk -F'/' '{print $5}')
		done
	#this elif looks like it is trying to support setting by slot only,
	#but that isn't supported by the rest of the script... fix or remove?
	elif [[ -d ${EROOT}${MSFPATH}${target} ]]; then
		ln -sf "metasploit${target}" "${EROOT}${MSFPATH}"
		for i in $(qlist metasploit | grep "/usr/libdir/${target}/msf")
		do
			ln -sf /usr/bin/msfloader /usr/bin/$(echo ${i} | awk -F'/' '{print $5}')
		done
	else
		die -q "Target \"$1\" doesn't appear to be valid!"
	fi
}

# wrapper to safely set the symlink
set_symlink_safe() {
	if [[ -L ${EROOT}${MSFPATH} ]]; then
		# existing symlink
		remove_symlink || die -q "Couldn't remove existing symlink"
		set_symlink "$1" || die -q "Couldn't set a new symlink"
		#um, why is there an env-update here?
		env-update
	elif [[ -e ${EROOT}${MSFPATH} ]]; then
		# we have something strange
		die -q "${EROOT}${MSFPATH} exists but is not a symlink"
	else
		set_symlink "$1" || die -q "Couldn't set a new symlink"
	fi
}

### show action ###

describe_show() {
	echo "Show the current metasploit symlink"
}

do_show() {
	write_list_start "Current metasploit symlink:"
	if [[ -L ${EROOT}${MSFPATH} ]]; then
		local metasploit=$(canonicalise "${EROOT}${MSFPATH}")
		write_kv_list_entry "${metasploit%/}" ""
	else
		write_kv_list_entry "(unset)" ""
	fi
}

### list action ###

describe_list() {
	echo "List available metasploit symlink targets"
}

do_list() {
	local i targets=( $(find_targets) )

	write_list_start "Available metasploit symlink targets:"
	for (( i = 0; i < ${#targets[@]}; i++ )); do
		[[ ${targets[i]} = \
			$(basename "$(canonicalise "${EROOT}${MSFPATH}")") ]] \
			&& targets[i]=$(highlight_marker "${targets[i]}")
	done
	write_numbered_list -m "(none found)" "${targets[@]}"
}

### set action ###

describe_set() {
	echo "Set a new metasploit symlink target"
}

describe_set_parameters() {
	echo "<target>"
}

describe_set_options() {
	echo "<target> : Target name or number (from 'list' action)"
	echo "--use-old : If an implementation is already set, use that one instead"
}

do_set() {
	local action="error"
	local current=$(basename "$(canonicalise "${EROOT}${MSFPATH}")")
	local available=( $(find_targets) )
	local new
	local opt

	while [[ ${#@} -gt 0 ]] ; do
		opt=$1
		shift
		case ${opt} in
			--use-old)
				if [[ -n "${current}" ]] && has "${current}" "${available[@]}"; then
					action="old-implementation"
				fi
			;;
			metasploit*)
				if [[ "${action}" != "old-implementation" ]] ; then
					action="set-implementation"
				fi

				if has ${opt} ${available[@]}; then
					new="${opt}"
				else
					echo "You need to emerge ${opt} before you try to eselect it"
				fi
			;;
			*)
				if [[ "${action}" != "old-implementation" ]] ; then
					action="set-implementation"
				fi

				if is_number ${opt} ; then
					#targets=( $(get_implementations) )
					new=${available[opt - 1]}
					if [[ -z ${new} ]] ; then
						die -q "Unrecognized option: ${opt}"
					fi
				else
					die -q "Unrecognized option: ${opt}"
				fi
			;;
		esac
	done

	case ${action} in
		old-implementation)
			set_symlink_safe ${current}
			return $?
		;;
		set-implementation)
			if [[ -n ${new} ]] ; then
				set_symlink_safe ${new}
				return $?
			else
				die -q "Please specify an implementation to set"
			fi
		;;
		*)
			die -q "Invalid usage of set action."
		;;
	esac
}