#!/bin/sh

volume_root='/run/angie'
tmp_dir="${volume_root}/tmp"
merged_root="${volume_root}/merged"
target_root="${volume_root}"
empty_dir='/var/lib/empty'

have_envvar() {
	[ -n "$1" ] || return 1
	grep -Ezq "^$1=" /proc/$$/environ || return
}

## unexporting variable in (POSIX) sh is PITA =/
unexport() {
	local ___k ___v
	for ___k ; do
		[ -n "${___k}" ] || continue
		have_envvar "${___k}" || continue

		___v=$(eval printf '%s' "\"\${${___k}}\"")
		eval "unset ${___k}"
		eval "${___k}=$(env printf '%s' \"\${___v}\")"
	done
}

## likely the same as in https://pkg.go.dev/strconv#ParseBool
gobool_to_int() {
	## local value=$1
	## local default=$2
	case "${1:-_}" in
	1 | [Tt] | [Tt][Rr][Uu][Ee] )     echo 1 ;;
	0 | [Ff] | [Ff][Aa][Ll][Ss][Ee] ) echo 0 ;;
	* ) echo "${2:-error}" ;;
	esac
}

[ -n "${__IEP_SRC:-}" ] || __IEP_SRC="$0"

log_always() {
	if [ "${IEP_DEBUG}" = 1 ] ; then
		echo "# $(date +'%Y-%m-%d %H:%M:%S.%03N %z'): ${__IEP_SRC}${*:+: $*}"
	else
		echo "# ${__IEP_SRC}${*:+: $*}"
	fi >&2
}

log() {
	[ "${IEP_VERBOSE}" = 0 ] || log_always "$@"
}

ln_s() {
	if [ "${IEP_VERBOSE}" = 0 ] ; then
		ln -s "$@" || return
	else
		ln -sv "$@" || return
	fi
}
cp_a() {
	if [ "${IEP_VERBOSE}" = 0 ] ; then
		cp -a "$@" || return
	else
		cp -av "$@" || return
	fi
}

ln_cp() {
	if [ -h "$1" ] ; then
		ln_s "$(readlink -e "$1")" "$2"
	else
		cp_a "$1" "$2"
	fi
}

have_cmd() { command -v "$1" >/dev/null 2>&1 || return ; }

strip_suffix() { printf '%s' "${1%"$2"}" | tr -s '/' ; }

install_userdir() {
	if [ "${IEP_ROOT}" = 1 ] ; then
		install -d -o "${NGX_USER}" -g "${NGX_GROUP}" "$@"
	else
		install -d "$@"
	fi
}

expand_file_envsubst() {
	local __ret __src __dst

	__ret=0
	for __src ; do
		[ -n "${__src}" ] || continue

		if ! [ -f "${__src}" ] ; then
			__ret=1
			log_always "file not found: ${__src}"
			continue
		fi

		case "${__src}" in
		*.in ) ;;
		* )
			__ret=1
			log "expand_file_envsubst: file name extension mismatch: ${__src}"
			continue
		;;
		esac

		__dst=$(strip_suffix "${__src}" '.in')
		if [ -e "${__dst}" ] ; then
			__ret=1
			log "expand_file_envsubst: destination file already exists: ${__dst}"
			continue
		fi

		log "Running envsubst: ${__src} -> ${__dst}"
		envsubst.sh < "${__src}" > "${__dst}" || __ret=1
	done
	return ${__ret}
}

expand_file_j2cfg() {
	j2cfg-single "$@" || return $?
}

expand_dir_envsubst() {
	local __template_list __have_args __ret __orig_file

	__template_list=$(mktemp) || return

	find "$@" -follow -name '*.in' -type f \
	| {
		if [ -n "${NGX_TEMPLATE_EXCLUDE_REGEX:-}" ] ; then
			grep -Ev -e "${NGX_TEMPLATE_EXCLUDE_REGEX}"
		elif [ -n "${NGX_TEMPLATE_INCLUDE_REGEX:-}" ] ; then
			grep -E -e "${NGX_TEMPLATE_INCLUDE_REGEX}"
		else
			cat
		fi
	} \
	| sort -uV > "${__template_list}"

	__ret=0
	if [ -s "${__template_list}" ] ; then
		__have_args="${ENVSUBST_ARGS:+1}"
		if [ -z "${__have_args}" ] ; then
			## optimize envsubst.sh invocation by caching argument list
			## ref: envsubst.sh
			ENVSUBST_ARGS=$(mktemp) || return
			envsubst-args.sh > "${ENVSUBST_ARGS}"
			export ENVSUBST_ARGS
		fi

		while read -r __orig_file ; do
			[ -n "${__orig_file}" ] || continue
			expand_file_envsubst "${__orig_file}" || __ret=1
		done < "${__template_list}"

		if [ -z "${__have_args}" ] ; then
			rm -f "${ENVSUBST_ARGS}" ; unset ENVSUBST_ARGS
		fi
		unset __have_args
	fi

	rm -f "${__template_list}" ; unset __template_list
	
	return ${__ret}
}

expand_dir_j2cfg() {
	local __template_list __ret

	__template_list=$(mktemp) || return

	find "$@" -follow -name '*.j2' -type f -printf '%p\0' \
	| {
		if [ -n "${NGX_TEMPLATE_EXCLUDE_REGEX:-}" ] ; then
			grep -zEv -e "${NGX_TEMPLATE_EXCLUDE_REGEX}"
		elif [ -n "${NGX_TEMPLATE_INCLUDE_REGEX:-}" ] ; then
			grep -zE -e "${NGX_TEMPLATE_INCLUDE_REGEX}"
		else
			cat
		fi
	} \
	| sort -zuV > "${__template_list}"

	__ret=0
	if [ -s "${__template_list}" ] ; then
		xargs -0r -n 1000 -a "${__template_list}" \
		j2cfg-multi < /dev/null || __ret=1
	fi

	rm -f "${__template_list}" ; unset __template_list

	return ${__ret}
}

is_builtin_module() {
	[ -n "${1:-}" ] || return 1
	[ -n "${2:-}" ] || return 1

	[ -f "/etc/angie/builtin.$1" ] || return 1
	[ -s "/etc/angie/builtin.$1" ] || return 1

	grep -Fxq -e "$2" "/etc/angie/builtin.$1" || return 1
}

append_list() {
	if [ -n "$2" ] ; then
		printf '%s' "${1:-}${1:+ }$2"
	else
		printf '%s' "$1"
	fi
}

prepend_list() {
	if [ -n "$2" ] ; then
		printf '%s' "$2${1:+ }${1:-}"
	else
		printf '%s' "$1"
	fi
}

list_have_item() {
	[ -n "$1" ] || return 1
	[ -n "$2" ] || return 1
	case " $1 " in
	*" $2 "* ) return 0 ;;
	* )        return 1 ;;
	esac
}

normalize_list() {
	[ -n "$1" ] || return 0

	printf '%s' "$1" \
	| sed -zE 's/[[:space:]]+/ /g;s/^ //;s/ $//'
}

sort_dedup_list() {
	[ -n "$1" ] || return 0

	printf '%s' "$1" \
	| tr -s '[:space:]' '\n' | sort -uV \
	| sed -zE 's/[[:space:]]+/ /g;s/^ //;s/ $//'
}

float_div() {
	mawk -v "a=$1" -v "b=$2" 'BEGIN{print a/b;exit;}' </dev/null
}

find_fast() {
	find "$@" -printf . -quit | grep -Fq .
}

randN() {
	od -v -A n -t x1 -N "$1" < /dev/urandom | tr -d '[:space:]'
}

re_ipv4_oct='[0-9]|[1-9][0-9]|[1-9][0-9][0-9]|2[0-4][0-9]|25[0-5]'
re_ipv4_addr="^${re_ipv4_oct}\.${re_ipv4_oct}\.${re_ipv4_oct}\.${re_ipv4_oct}\$"
is_ipv4_address() {
	[ -n "$1" ] || return 1
	printf '%s' "$1" | grep -zEq "${re_ipv4_addr}" || return 1
}