#!/bin/sh
set -eu

usage() {
	cat <<-'EOF'
		Usage:
		  lang-for FILE
		  lang-for -h
	EOF
}

help() {
	cat <<-'EOF'


		Options:
		  -h, --help    show this message

		  FILE          the path of the file to get the language for


		Say the language of the given file, using the path of FILE.


		Examples:

		  Get "en" for "src/en/some-pt.md":

		    $ lang-for src/en/some-pt.md
		    en
	EOF
}


for flag in "$@"; do
	case "$flag" in
		--)
			break
			;;
		--help)
			usage
			help
			exit
			;;
		*)
			;;
	esac
done

while getopts 'h' flag; do
	case "$flag" in
		h)
			usage
			help
			exit
			;;
		*)
			usage >&2
			exit 2
			;;
	esac
done
shift $((OPTIND - 1))

. src/lib.sh


FILE="${1:-}"
eval "$(assert_arg "$FILE" 'FILE')"


echo "${FILE#"$CONTENT_PREFIX"/}" |
	cut -d/ -f1