#!/bin/sh

# This script aims to offer a friendly interface to manage runit services
# Requires:
# * dialog
# * find
# * $SVDIR which indicates the supervision folder
# * $SVKNOWN which indicates a colon-separated list of places to search for
#     existing services (duplicated services are *not* supported... yet?)
# * $ACTION indicates how to manipulate services
#
# Currently supported $ACTION values:
# * install: allows to register/unregister known services;
#
# Planned to support $ACTION values:
# * enable: allows to enable/disable known services;
# * toggle: same, via down file;

printf "SVDIR=%s\nSVKNOWN=%s\n" ${SVDIR:="/etc/service"} ${SVKNOWN:="/etc/sv/"} >&2
ACTION="enable"
SV_LIST=""

FINDOPT="-mindepth 1 -maxdepth 2 -name run "
for SOURCE in $(printf ${SVKNOWN} | tr ':' '\t')
do
	SV_LIST="$SV_LIST	$(find -H $SOURCE $FINDOPT -exec sh -c \
		'printf "%s %s off\n" $(dirname {}) $(dirname {})' \; | sort)"
done

SV_ENABLED=$(find -L ${SVDIR} $FINDOPT -exec sh -c \
	'printf " -e '\''/%s off$/ s/off$/on/g'\'' " $(basename $(dirname {}))' \;)

SV_CURRENT=$(printf "%s %s %s\n" $SV_LIST | eval sed $SV_ENABLED)

DIALOG=$(mktemp -d)
dialog --no-tags --checklist "List of service to $ACTION:" 0 0 0 $SV_CURRENT 2> $DIALOG/out
SV_NEW_ENABLED=$(tr ' ' '\n' < $DIALOG/out | awk -F/ '{printf " -e '\''/%s off$/ s/off$/on/g'\'' \n", $NF}END{printf "\n"}')
SV_NEXT=$(printf "%s %s %s\n" $SV_LIST | eval sed $SV_NEW_ENABLED)

printf "%s\n" "$SV_CURRENT" > $DIALOG/curr
printf "%s\n" "$SV_NEXT" > $DIALOG/next
AWKPROG='
{
	if( $2 != $3 )
	{
		if( $2 == "on" )
		{
			last = split( $1, elem, "/" );
			printf "rm %s/%s\n", svdir, elem[last];
		}
		else
		{
			printf "ln -s %s %s/\n", $1, svdir;
		}
	}
}
'
paste -d ' ' $DIALOG/curr $DIALOG/next | cut -f1,3,6 -d ' ' | awk -F' ' -v svdir="$SVDIR" "$AWKPROG"
rm -r $DIALOG