#!/bin/bash
# Takes a list of YouTube URLs on stdin. URLs for autogenerated channels are written to FD 3, all other URLs go to stdout.
while read -r url
do
	if [[ "${url}" == */channel/* ]]
	then
		header="$(curl -4sL -A 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36' -H 'Accept-Language: en-US,en;q=0.5' "${url}?disable_polymer=1" | \
			tr -d '\n' | \
			grep -Po '<div\s([^>]*\s)?class="([^"]* )?channel-header( [^"]*)?".*?<div\s([^>]*\s)?id="channel-subheader"')"
		if grep -qP '<span\s([^>]*\s)?class="([^"]+ )?yt-channel-title-autogenerated[ "]' <<<"${header}"
		then
			echo "${url}" >&3
			continue
		fi
	fi
	echo "${url}"
done