#!/bin/bash
#  Copyright (C) 2010  Matias A. Fonzo, Santiago del Estero, Argentina
#
#  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 3 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/>.

# Localización % Idioma:
TEXTDOMAINDIR=/usr/share/locale
TEXTDOMAIN=size

VERSION=0.1

# Funciones #

# Una función para mostrar mensajes normales:
msg() { printf '%s\n' "$@"; }

# Una función para mensajes de advertencia:
warn() { printf '%b\n' "$@" >&2; }

usage() {
  msg $"Displays the size of one or more packages."                        \
       ""                                                                  \
      $"Usage: size [options] package.tlz ..."                             \
       ""                                                                  \
      "Options:"                                                           \
      $"  -h, --help                Show this help and exit."              \
      $"  -v, --version             Show the version of the program."      \
       ""
}

version() {
  msg "size $VERSION"                                                      \
      "Copyright (C) 2010 Matias A. Fonzo <selk@dragora.org>."             \
      "License GPLv3+: GNU GPL version 3 or later:"                        \
      "<http://gnu.org/licenses/gpl.html>"                                 \
      "This is free software: you are free to change and redistribute it." \
      "There is NO WARRANTY, to the extent permitted by law."
}

# Opciones % Argumentos:
while [[ $# -gt 0 ]]; do
  case "$1" in
    -[h?]|--help)
      usage
      exit 0
      ;;
    -[vV]|--version)
      version
      exit 0
      ;;
    -*)
      warn $"${0##*/}: Invalid option: $1"
      exit 1
      ;;
    *)
      break;
  esac
done

# Si no hay argumentos, llama a la función de ayuda:
(( $# == 0 )) && { usage ; exit 0; }

# Sale ante cualquier error:
set -e

# Más funciones #

# Una función para reflejar el nombre base:
_basename() { local name ; name=${1##*/} ; printf "${name%$2}"; }

pick_up() {
  while read line ; do
    printf $line
  done
}

# Variables #

# Directorio y archivo temporal:
TMP=${TMP:-/tmp}
TEMPFILE=${TMP}/pkg-size$$

# Chequeo de sanidad:
if [[ ! -d $TMP ]]; then
  mkdir -p $TMP
fi

# Cuerpo #

# Loop:
for file in "$@" ; do
  if [[ -f $file ]]; then
    NAME=$(_basename $file .tlz)

    # Comprueba la extensión del archivo:
    if [[ ${file##*/} != ${NAME}.tlz ]]; then
      warn "${file}: Does not end in .tlz"
      CODE=1
      continue;
    fi

    # Determina el tamaño del archivo comprimido:
    COMPRESSED="$(du -h $file | pick_up)"

    # Determina el tamaño del archivo descomprimido:
    LC_ALL=C tar --use-compress-program=lzip --totals \
     -tf $file > /dev/null 2> $TEMPFILE

    UNCOMPRESSED="$(awk '$3 == "read:" \
     { l=length($5) ; print(substr($5,1,l-3)) }' $TEMPFILE)"

    UNCOMPRESSED=${UNCOMPRESSED#*(}  # Remueve un paréntesis.

    # Muestra el sumario:
    msg $"Package           =  ${NAME}.tlz"   \
        $"Compressed size   =  $COMPRESSED"   \
        $"Uncompressed size =  $UNCOMPRESSED" \
         ""
  else
    warn $"${0##*/}: ${file}: File not found or non-regular"
    EXIT_CODE=1
    continue;
  fi
done

rm -f $TEMPFILE
exit $EXIT_CODE