#!/bin/bash
# FILE:       	admin/user/del
# DESCRIPTION:	Delete a user from admin UI
# USAGE:      	del $remote_ip $querystring
# QUERYSTRING:	?t=$token&user=$username&un=$usernumber

source /etc/wagon/config
ip="${1}"; qs="$(<<<"${2}" tr '&' '\n' | sed 's/?//')"

# Check token
token_fail(){
	printf 'Rejecting admin %s request for new peer due to %s token\n' "${ip}" "${1}" >&2
	printf 'Invalid token\n' | /usr/lib/wagon/http_res 403; exit
}
saved_token="$(grep "${ip}" /var/local/wagon/tokens | cut -f2)"
[ "${saved_token}" == "" ] && token_fail 'missing'
<<<"${qs}" grep -qx "t=${saved_token}" || token_fail 'mismatched'
printf '%s token was valid\n' "${ip}" >&2

# Check username and usernumber
username="$(<<<"${qs}" grep -oP 'user=(.*)' | sed 's/^user=//')"
usernumber="$(<<<"${qs}" grep -oP 'un=(.*)' | sed 's/^un=//')"
if [[ "${username}" == "" ]]; then
	printf 'ERROR! Username missing!\n' | tee >(cat 1>&2) | /usr/lib/wagon/http_res 400; exit
elif [[ "${usernumber}" == "" ]]; then
	printf 'ERROR! Usernumber missing!\n' | tee >(cat 1>&2) |/usr/lib/wagon/http_res 400; exit
else
	printf 'Admin %s requested deletion of user "%s" with usernumber "%s"\n' "${ip}" "${username}" "${usernumber}" >&2
fi

# Get all peer IPs
if ! wg_output="$(sudo /usr/bin/wg show "${TLD}" allowed-ips)"; then
	printf 'ERROR! Wireguard failed!\n' >&2
	/usr/lib/wagon/http_res 500; exit
fi

# Filter out the user's
user_peers="$(grep "${IPV4_NET%.*.*}.${usernumber}." <<<"${wg_output}" 2>/dev/null)"
if [ "${user_peers}" == "" ]; then
	printf "ERROR! Couldn't find any peers for %s!\n" "${IPV4_NET%.*.*}.${usernumber}." >&2
	/usr/lib/wagon/http_res 500; exit
fi

# Get user peer domains
if ! peers="$(/usr/lib/wagon/ips_to_peers tsv <<<"${user_peers}")"; then
	printf 'ERROR! Failed to retrieve domains for peers for %s!\n' "${IPV4_NET%.*.*}.${usernumber}" >&2
	/usr/lib/wagon/http_res 500; exit
fi

# Run this function in parallel in the while loop below
# https://stackoverflow.com/a/33058618
for_server_do() {
	[[ ${server_hostname:0:1} = \# ]] && return # Ignore comments
	server_hostname="${1}"; server_ipv4="${2}"; server_ipv6="${3}"; server_pubkey="${4}"
	server_endpoint="${5}"; server_url="${6}"; server_secret="${7}"
	if [ "${server_hostname}" == "${LOCAL_SERVER}" ]; then
		# Local server
		if /usr/lib/wagon/wg_peer_del "${pubkey}"; then
			printf 'Deleted %s from local wireguard server.\n' "${domain}" >&2
		else
			printf 'ERROR! Failed to delete %s from local wireguard server!\n' "${domain}" >&2
			# TODO: clear existing progress
			/usr/lib/wagon/http_res 500; exit
		fi
	else
		# Federated server
		if /usr/lib/wagon/fed_peer_del "${server_url}" "${server_secret}" "${pubkey}"; then
			printf 'Deleted %s from remote wireguard server %s.\n' "${domain}" "${server_hostname}" >&2
		else
			printf 'ERROR! Failed to delete %s from remote wireguard server %s!\n' "${domain}" "${server_hostname}" >&2
			/usr/lib/wagon/http_res 500; exit
		fi
	fi
}

# Delete user peers (in parallel)
delete_peer() {
	domain="${1}"; ipv4="${2}"; ipv6="${3}"; pubkey="${4}"
	username="$(<<<"${domain}" cut -d'.' -f2)"
	printf 'Deleting peer %s\n' "${domain}" >&2

	# Remove peer from wireguard
	while IFS=$'\t' read -r server_hostname server_ipv4 server_ipv6 server_pubkey server_endpoint server_url server_secret
		do for_server_do "${server_hostname}" "${server_ipv4}" "${server_ipv6}" "${server_pubkey}" "${server_endpoint}" "${server_url}" "${server_secret}" &
	done </etc/wagon/servers &

	# Remove peer from nameserver
	if /usr/lib/wagon/ns_update_del "${domain:?}" "${ipv4:?}" "${ipv6:?}"
		then printf 'Successfully deleted %s from DNS server.\n' "${domain}" >&2
		else printf 'ERROR! Failed to delete %s %s %s from DNS server!\n' "${domain}" "${ipv4}" "${ipv6}" >&2
	fi
}
printf '%s\n' "${peers}" | while IFS=$'\t' read -r domain ipv4 ipv6 pubkey
	do delete_peer "${domain}" "${ipv4}" "${ipv6}" "${pubkey}" &
	[ "$(jobs | wc -l)" -ge "$(nproc)" ] && wait
done

# Delete SSL cert directory
if ! sudo rm -rf "${SSL_CONFIG_DIR:?}/${username:?}/"; then
	printf 'Failed to delete user SSL directory %s/%s/:\n' "${SSL_CONFIG_DIR}" "${username}" >&2
fi

# Respond to user
# Do it before updating nameserver and certs because
# if wireguard worked, there's no going back.  The admin
# can clean up missing records and certs after checking the logs
printf 'Deleted %s' "${username}" | /usr/lib/wagon/http_res 202