#!/usr/bin/env bash
# Apt-P2P Clean
#
# Douglas Thrift
#
# $Id$

function usage()
{
	cat <<-EOF
	Usage: $program [options]

	Options:
	  -e, --execute     clean up the apt-p2p cache
	  -h, --help        show this help message and exit
	  -n, --no-execute  show what would be done to clean up the apt-p2p cache
	  -v, --version     show version information and exit
	EOF
	exit $@
}

function version()
{
	echo "$program $version"
	exit
}

program=`basename $0`
version='1.0'
apt_p2p_cache='/var/cache/apt-p2p/cache'
apt_archive='/var/cache/apt/archives'
args=`getopt -l 'execute,help,no-execute,version' -n "$program" -o 'ehnv' -- "$@"`
val=$?

[[ $val != 0 ]] && usage $val

eval set -- "$args"
unset args val

until [[ "$1" == -- ]]; do
	case "$1" in
	(-e|--execute)
		execute=1
		;;
	(-h|--help)
		usage
		;;
	(-n|--no-execute)
		execute=0
		;;
	(-v|--version)
		version
		;;
	esac

	shift
done

[[ -z $execute ]] && usage

set -e

for directory in "$apt_p2p_cache" "$apt_archive"; do
	if [[ ! -r "$directory" ]] || [[ ! -x "$directory" ]]; then
		echo "$program: $directory: Permission denied" 1>&2
		exit 1
	fi
done

if [[ $execute -eq 1 ]]; then
	echo 'Removing files:'
else
	echo 'Would remove files:'
fi

find "$apt_p2p_cache" -name '*.deb' | (
	freed=0
	
	while read deb; do
		if [[ ! -f "$apt_archive/${deb##*/}" ]]; then
			((freed += `du -B 1 $deb | cut -f 1`))

			echo " ${deb##*/}"

			[[ $execute -eq 1 ]] && rm -f "$deb"
		fi
	done

	if [[ $execute -eq 1 ]]; then
		[[ $freed != 0 ]] && invoke-rc.d apt-p2p restart

		echo -n 'Freed'
	else
		echo -n 'Would free'
	fi

	echo " `bc <<-EOF
	freed=$freed
	scale=1
	if (freed >= 1024 ^ 3) print freed / 1024 ^ 3, "G" else if (freed >= 1024 ^ 2) print freed / 1024 ^ 2, "M" else if (freed >= 1024) print freed / 1024, "K" else freed
	EOF`B of disk space"
)

# Clean up Apt-P2P cache