#!/bin/bash

set -u

declare ALT_LINK LINK
declare -a browsers

browsers=(
firefox
palemoon
waterfox
)

get_link_base() {
	echo "${1}"|awk -F/ '{print $1"//"$3}'
}

onionize_link() {
	local s1 s2
	s1=
	s2=
	ALT_LINK="${LINK}"
	case "${LINK}" in
		*facebook.com*)
			s1=facebook.com
			s2=facebookcorewwwi.onion
			ALT_LINK="${LINK/facebook.com/facebookcorewwwi.onion}"
			;;
		*www.prorepubica.org*)
			s1=www.propublica.org
			s2=p53lf57qovyuvwsc6xnrppyply3vtqm7l6pcobkmyqsiofyeznfu5uqd.onion
			;;
		*riseup.net*)
			s1=riseup.net
			s2=vww6ybal4bd7szmgncyruucpgfkqahzddi37ktceo3ah7ngmcopnpyyd.onion
			;;
	esac

	[[ -z ${s1} ]] || {
		ALT_LINK=${LINK/"${s1}"/"${s2}"}
	}
}

LINK="${1:-not set}"
[[ -z "${LINK}" || "${LINK}" = "not set" ]] && {
	echo bad or missing link
   	exit
}


# PRE Adjust domains for .onion addresses where possible
#  (some links are better changed early, others need POST work)
onionize_link

# IF link adjusted above, use new link
[[ "${LINK}" = "${ALT_LINK}" ]] || {
	echo -e "\nNew alternate link: ${ALT_LINK}"
	LINK="${ALT_LINK}"
}

link_base=$(get_link_base "${LINK}")
echo -e "\nFirst Link Base: ${link_base}"
loc_lnk='not yet'

while :
do

	echo '------------------------------'

	# If download link redirects to a new Location, use that
	echo -en "\nGet location at $(date)\t\t"
	loc_lnk=$(
		curl -I4s "${LINK}" | \
			awk '/^[Ll]ocation:/{$1="";gsub(/^[ \t]+|[\r]/, "");print}'
	)
	# the following doesn't keep following the redirects
	#loc_lnk=$(curl -so/dev/null -Iw'%{redirect_url}\n' "${LINK}")
	[ -z "${loc_lnk}" ] && {
		echo -e "no more redirects"
		break
	}

	echo -e "${loc_lnk}"

	# fix relative link to full link if we've lost base link
	if [[ "${loc_lnk:0:1}" = "/" ]]
	then
		loc_lnk="${link_base}${loc_lnk}"
	else
		link_base=$(get_link_base "${loc_lnk}")
		echo -e "\nNew Link Base: ${link_base}"
	fi

	echo -e "\nlocation link: ${loc_lnk}"
	LINK="${loc_lnk}"

done

# POST Adjust domains for other special .onion addresses where possible
# - this is just in case an early link wasn't able to be onionized 
#   ... but a redirect link can
onionize_link

# IF link adjusted above, use new link
[[ "${LINK}" = "${ALT_LINK}" ]] || {
	echo -e "\nNew alternate link: ${ALT_LINK}"
	LINK="${ALT_LINK}"
}

echo
echo '------------------------------'

echo
echo "${LINK}"
echo

# Now remove all parameters passed with the URL
#  -- clear possible junk --
LINK=${LINK%%[?]*}
echo "${LINK}"
echo
for browser in "${browsers[@]}"
do
	printf "%15s \"%s\"\n\n" "${browser}" "${LINK}"
done