#!/bin/sh
# pacsize -- display package sizes
#
# Copyright (C) 2014 Pierre Neidhardt <ambrevar@gmail.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

readonly myname='pacsize'
readonly myver='4.1.2'

calc_total () {
	awk 'BEGIN {
	unit["B"] = 1/1024
	unit["KiB"] = 1
	unit["MiB"] = 1024
	unit["GiB"] = 1048576
	unit["TiB"] = 1073741824
	unit["PiB"] = 1099511627776
	unit["EiB"] = 1125899906842624
	unit["ZiB"] = 1152921504606846976
	unit["YiB"] = 1180591620717411303424
}

{
	u=$1
	gsub(/[[:digit:]]*/, "", u)
	n=$1
	gsub(/[[:alpha:]]*/, "", n)
	total += unit[u]*n
	print
}
END {
	printf ("%7s KIB TOTAL\n", total)
}'
}

error () {
	echo >&2 "$@"
}

## Print size and name. We round to the lowest integer, this makes output
## lighter.
filter () {
	awk -F ": " \
		'$0 ~ "^Name" {
	pkg = $2
}
$0 ~ "^Installed Size" {
	split($2, a, " ")
	printf ("%4d%-3s %s\n", a[1], a[2], pkg)
}'
}

remove_duplicates () {
	awk '! table[$0]++'
}

usage () {
	cat <<EOF>&2
Usage: ${0##*/} [OPTIONS] PACKAGES
       ${0##*/} -a [OPTIONS]

Display the size of PACKAGES. Duplicates are removed if any. The local database
is queried first; if the package is not found, the sync database is then used
for lookup.

Options:

  -a: Process all installed packages.
  -h: Show this help.
  -n: Sort output by name.
  -s: Sort output by size.
  -t: Print total.
  -V: Show version information.

Examples:

  $ ${0##*/} -ast
    Convenient way to keep track of big packages.

  $ ${0##*/} \$(pactree -ld1 linux)
    Print the size of linux and all its direct dependencies.

  $ ${0##*/} -st \$(pacman -Qdtq)
    Print a grand total of orphan packages, and sort by size.
EOF
}

version () {
	echo "$myname $myver"
	echo 'Copyright (C) 2014 Pierre Neidhardt <ambrevar@gmail.com>'
}

opt_sort=false
opt_all=false
opt_total=false

while getopts ":ahnstV" opt; do
	case $opt in
	a)
		opt_all=true ;;
	h)
		usage
		exit ;;
	n)
		opt_sort="sort -k3" ;;
	s)
		opt_sort="sort -h" ;;
	t)
		opt_total="calc_total" ;;
	V)
		version "$0"
		exit ;;
	\?)
		usage
		exit 1 ;;
	esac
done

shift $((OPTIND - 1))

## All-packages mode.
## We use a dedicated algorithm which is much faster than per-package mode.
## Unfortunately there is no easy way to select packages with this method.
if $opt_all; then
	DBPath="$(awk -F "=[ \t]*" '/^[ \t]*DBPath[ \t]*=/{gsub(/[ \t]*$/, "", $2); print $2}' /etc/pacman.conf 2>/dev/null)"
	[ -z "$DBPath" ] && DBPath="/var/lib/pacman"

	if [ ! -d "$DBPath/local/" ]; then
		error "Could not find local database in $DBPath/local/."
		exit 1
	fi

	awk 'BEGIN {
	split("B KiB MiB GiB TiB PiB EiB ZiB YiB", unit)
}
$0 == "%NAME%" {
	getline pkg
}
$0 == "%SIZE%" {
	getline size
	i = 1
	while (size > 2048) {
		size /= 1024
		i++
	}
	printf ("%4d%-3s %s\n", size, unit[i], pkg)
}' "$DBPath"/local/*/desc | { $opt_sort || cat ;} | { $opt_total || cat ;}
	exit
fi

## Per-package mode.
if [ $# -eq 0 ]; then
	error "Missing argument."
	usage
	exit 1
fi

## Remove this check if integrated to pacman.
if ! command -v pacman >/dev/null 2>&1; then
	error "'pacman' not found"
	exit 1
fi

{
	## If package is not found locally (-Q), we use the sync database (-S). We
	## use LC_ALL=C to make sure pacman output is not localized.
	buffer=$(LC_ALL=C pacman -Qi "$@" 2>&1 1>&3 3>&- | cut -f2 -d "'")
	[ -n "$buffer" ] && LC_ALL=C pacman -Si "$buffer"
} 3>&1 | filter | { $opt_sort || remove_duplicates ;} | { $opt_total || cat ;}