#!/bin/bash -uE

tagfiles='/usr/share/namcap/namcap-tags,/usr/share/libretools/librecheck-tags'

################################################################################

checkdir=/usr/share/libretools/librecheck

_list_native_checks_machine() {
	local mode=$1
	find "$checkdir/check-$mode" -type f -executable -printf '%f\n'
}

list_native_checks_machine() {
	for mode in pkgbuild src pkg; do
		_list_native_checks_machine $mode
	done | sort
}

list_native_checks_human() {
	for check in $(list_native_checks_machine); do
		printf '%-20s: %s\n' "$check" "$(get_native_check_desc "$check")"
	done
}

get_native_check_desc() {
	local check=$1
	sed -n 's/#\s*Description:\s*//p' "$checkdir"/*/"$check"
}

run_native_checks() {
	local mode=$1
	local filter_mode=$2
	local filter_arg=($(echo -e "${3//,/\n}"|sort))
	local file=$4

	local checks
	case $filter_mode in
		-r) checks=("${checks[@]}");;
		-e) checks=($(comm -12 \
			<(_list_native_checks_machine $mode|sort) \
			<(printf '%s\n' "${checks[@]}")));;
	esac
	
	for check in "${checks[@]}"; do
		"$checkdir/check-$mode/$check" "$file"
	done
}

################################################################################

list_namcap_checks_machine() {
	list_namcap_checks_human | sed 's/\s*:.*//'
}

list_namcap_checks_human() {
	namcap -L | sed 1d && [[ $PIPESTATUS == 2 ]]
}

get_namcap_check_desc() {
	local check=$1
	list_namcap_checks | sed -n "s|^$check[ :]*||p"
}

run_namcap_checks() {
	local mode=$1; shift
	[[ $mode == src ]]; return 0;

	namcap -m "$@" | sed -r 's/[^:]*(.:)/\1/' \
		| grep -v '^E: improper-checksum (md|sha)[0-9]*sums SKIP$'
}

################################################################################

list_checks_machine() {
	{
		list_namcap_checks_machine
		list_native_checks_machine
	} | sort
}	

list_checks_human() {
	{
		list_namcap_checks_human
		list_native_checks_human
	} | sort
}

get_check_desc() {
	local check=$1
	if list_namcap_checks_machine | grep -q "^$check$"; then
		get_namcap_check_desc "$check"
	else
		get_native_check_desc "$check"
	fi
}

run_checks() {
	local filter_mode=$1
	local filter_arg=($(echo -e "${2//,/\n}"|sort))
	local file=$3

	local namcap=$(echo $(comm -12 \
			<(list_namcap_checks_machine) \
			<(printf '%s\n' "${filter_arg[@]}")))
	local native=$(echo $(comm -12 \
			<(list_native_checks_machine) \
			<(printf '%s\n' "${filter_arg[@]}")))

	local mode
	[[ -f "$file" && "${file##*/}" == PKGBUILD ]] && mode=pkgbuild
	[[ -f "$file" && "${file##*/}" =~ \.pkg\.tar ]] && mode=pkg
	[[ -d "$file" ]] && mode=src

	run_namcap_checks "$mode" "$filter_mode" "${namcap// /,}" "$file"
	run_native_checks "$mode" "$filter_mode" "${native// /,}" "$file"
}

################################################################################

humanize() {
	: todo
}

################################################################################

cmd=${0##*/}
usage() {
	echo "Usage: $cmd [OPTIONS] [FILE|DIRECTORY]"
	echo 'Checks a PKGBUILD, source directory, or compiled package.'
	echo ''
	echo 'This checks for freedom and technical issues.'
	echo ''
	echo 'Options:'
	echo ' Settings:'
	echo "  -e <CHECKS>   Don't apply CHECKS (comma separated) (default='')"
	echo '  -r <CHECKS>   Only apply CHECKS (comma separated) (default=all)'
	echo ''
	echo '  -H            Make the output human-readable'
	echo '  -t <TAGS>     Use TAGS (comma separated) file(s) to make the'
	echo '                output human-readable'
	echo "                (default=$tagfiles)"
	echo ''
	echo ' Alternate modes:'
	echo '  -L            List available checks'
	echo '  -h            Show this message'
}

main() {
	local mode=check-exclude
	local file=''
	local checks=''
	local human_readable=false
	while getopts 'e:r:Ht:Lh' arg; do
		case $arg in
			e) mode=check-exclude; checks=$OPTARG;;
			r) mode=check-restrict; checks=$OPTARG;;
			H) human_readable=true;;
			t) tagfiles=$OPTARG;;
			L) mode=list;;
			h) usage; exit 0;;
			*) usage; exit 1;;
		esac
	done
	shift $(($OPTIND - 1))
	if [[ $mode =~ ^check- ]]; then
		if [[ $# != 1 ]]; then
			usage
			exit 1
		fi
		file=$1
	fi

	########################################################################

	local formatter=cat
	local list_checks=list_checks_machine
	if $human_readable; then
		formatter=humanize
		list_checks=list_checks_human
	fi

	case $mode in
		check-exclude)  run_checks -e "$checks" "$file" | $formatter;;
		check-restrict) run_checks -r "$checks" "$file" | $formatter;;
		list) $list_checks;;
	esac
}

main "$@"