env/bin/invidious.sh

#!/bin/sh
# invidious
# Written in 2019 by Leslie
# Modified in 2019-2020 by Lucas
# CC0 1.0 Universal/Public domain - No rights reserved
#
# To the extent possible under law, the author(s) have dedicated all
# copyright and related and neighboring rights to this software to the
# public domain worldwide. This software is distributed without any
# warranty. You should have received a copy of the CC0 Public Domain
# Dedication along with this software. If not, see
# <http://creativecommons.org/publicdomain/zero/1.0/>.

usage()
{
	printf "Usage: [-T] %s url\n" "${0##*/}" >&2
	exit 1
}

err()
{
	printf "%s: %s\n" "${0##*/}" "$*" >&2
	exit 1
}

api()
{
	printf "https://%s%s\n" "$INVIDIOUS" "$*"
}

known_site()
{
	printf "%s\n" "$1" | grep -Eq \
	    -e "^https://(www\.)?youtube\.com/" \
	    -e "^https://youtu\.be/" \
	    -e "^https://(www\.)?invidio\.us/" \
	    -e "^https://invidious\.snopyta\.org/" \
	    -e "^https://yewtu\.be/"
}

: ${INVIDIOUS:=invidious.snopyta.org}

torsocks=torsocks
while getopts T flag; do
	case $flag in
	T)	torsocks=
		;;
	*)	usage
		;;
	esac
done
shift $((OPTIND - 1))
[ $# -eq 1 ] || usage

url=$1
known_site "$url" || err "Unknown site: $url"

oldIFS=$IFS
IFS="&"
set -- ${url##*"?"}
IFS=$oldIFS

id=
for param; do
	case $param in
	v=*)	id=${param#v=}
		[ ${#id} -eq 11 ] || err "invalid video ID"
		;;
	esac
done

[ -n "$id" ] || err "no video ID in URL"

# XXX choose in some clever way
itag=$(torsocks ftp -MVo - "$(api "/api/v1/videos/$id")" |
    jq -r ".formatStreams[].itag" | head -n 1)
api "/latest_version?id=$id&itag=$itag"