#!/bin/bash
#
# pkgfoster 2005-11-27
# Jukka Heino <jukka@karsikkopuu.net>
#
# pkgfoster is a simple script you can use to clean up orphaned packages (i.e. 
# packages which no other package depends on). It uses prt-cache by default, so 
# remember to build the cache with "prt-get cache". You can also use normal 
# prt-get by modifying the PRT_GET variable. An array of packages to keep 
# is stored in the FOSTERED variable. Packages from core are never considered
# for deletion.
#

PRT_GET=prt-cache

if [ $UID = 0 ]; then
	PKGRM=pkgrm
else
	if command -v doas; then
		PKGRM="doas pkgrm"
	elif command -v sudo; then
		PKGRM="sudo pkgrm"
	else
		PKGRM="su -c pkgrm"
	fi
fi

BASE=$(awk '/^[[:space:]]*prtdir.*\/core/ {print $2}' /etc/prt-get.conf)
CONF=${XDG_CONFIG_HOME:="$HOME/.config"}/pkgfoster.conf
[ -f $CONF ] && . $CONF || mkdir -p ${XDG_CONFIG_HOME}

echo "Checking packages for orphans..."

while true ; do
	RECHECK=0

	orphans=$(comm -13 <(cat <(find "$BASE" -maxdepth 1 -type d -printf "%f\n") \
		<(for (( k=0; k<${#FOSTERED[@]}; k++ )); do echo "${FOSTERED[$k]}"; done) \
		| sort -u) <($PRT_GET listorphans | sort) | tr '\n' ' ')

	for PACKAGE in ${orphans[@]}; do
		echo
		$PRT_GET info $PACKAGE
		echo

		echo -n "Uninstall $PACKAGE? (y/N) "
		read ANSWER

		if [ "$ANSWER" = "y" ] ; then
			$PKGRM $PACKAGE
			RECHECK=1
		else
			FOSTERED=( $PACKAGE ${FOSTERED[@]} )
		fi
	done

	if [ "$RECHECK" = "0" ] ; then
		echo -n "FOSTERED=(" > $CONF
		for (( k=0; k<${#FOSTERED[@]}; k++ )); do
			echo -n "${FOSTERED[$k]} " >> $CONF
		done
		echo ")" >> $CONF
		exit 0
	fi

	echo
	echo "Re-checking packages for new orphans..."
done