#!/bin/bash

# jemerge - Permite seleccionar los paquetes en un emerge -puD world
# Copyright (C) 2004  Jonathan Hernández Velasco
# web: http://jhernandez.gpltarragona.org
# email: jbilbo (arroba/at) ya.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, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

# jemerge esta basado en femerge 1.0:
# femerge 1.0 by Martin Aspeli <optilude@gmx.net>

# Uso i requerimientos
# --------------------
# Este script necesita pfilter.
# Se utiliza ejecutandolo así: jemerge
# Su uso posterior es muy intuitivo.
# Si interrumpimos el emerge, restauramos con jemerge --last

# CHANGELOG
# -----------------------------------------------------------------------------
# 2004-06-07
# - Initial Release
# 2004-06-08
# - Añadida opción --last por parámetro. Si se interrumpe un emerge,
#   se puede restaurar. Uso: jemerge --last
# - Añadida opción para emerger con nohup
# -----------------------------------------------------------------------------

source /sbin/functions.sh

trap "error 'interrupted'" SIGINT SIGHUP SIGINT

###############################################################################
# Edit these if necessary (e.g. set final_emerge_cmd to semerge to use semerge)

emerge_cmd="emerge"       # command used to get emerge -p output.
final_emerge_cmd="emerge" # command used to actually emerge the packages
pfilter_cmd="pfilter"     # command used to filter the packages
###############################################################################
# Do not edit anything below this line

emerge_packages=""        # initial list of packages/profile to emerge
oneshot=1              # set to 1 to not touch world file

# print a message and exit
cancelled () {
  ewarn "Cancelado."
  echo
  exit 0
}

# print an error message and exit
error () {
  eend 1 "Error: ${1}"
  exit 1
}

# apply pfilter to the emerge-ouput passed as $1
filter_packages () {
  echo "${1}" | ${pfilter_cmd}
}
 
# do an emerge pretend with non-final options
preview_emerge () {
  ${emerge_cmd} -pvuD world || \
   error "${emerge_cmd} -p ${@} failed."
}

preview_emerge2 () {
  ${emerge_cmd} -pv ${@} || \
   error "${emerge_cmd} -p ${@} failed."
}

#$emerge_packages (what's being emerged)
get_options () {

  local goahead=0
  # Get options
  while true ; do

  test "${1}" != "" && emerge_packages="${emerge_packages} ${1}"

   shift || break
  done

  return ${goahead}
}

# Main:

if [ "$1" = "--last" ]; then
  einfo "ejecutando última instrucción: "
  if [ ! -r /tmp/.jemerge.last ]; then
    ewarn "no hay o no se puede leer última instrucción"
    exit -1
  fi
  `cat /tmp/.jemerge.last`
  echo
  rm -f /tmp/.jemerge.last
  exit 0
fi

# Get emerge command line options and packages/profile to emerge
if ! get_options ${@} ; then
  ewarn "Falling back on ${final_emerge_cmd}"
  ${final_emerge_cmd} ${@}
  exit ${?}
fi

einfo "Calculando dependencias..."
emerge_output=$(preview_emerge ${emerge_packages})
packages=""

# loop until exit by abort or emerge
while true ; do
 
  # Filter the packages we have so far"
  packages=$(filter_packages "${emerge_output}")
  test "${packages}" = "" && cancelled
 
  # Preview the emerge
  einfo "Calculating dependencies..."
  emerge_output=$(preview_emerge2 ${packages})
  echo "${emerge_output}"
  echo
 
  # Ask for action
  choice=""
  until test "${choice}" = "e" -o "${choice}" = "E" -o \
          "${choice}" = "b" -o "${choice}" = "B" -o \
          "${choice}" = "n" -o "${choice}" = "N" -o \
          "${choice}" = "f" -o "${choice}" = "F" -o \
          "${choice}" = "a" -o "${choice}" = "A" ; do
 
   einfon "Apreta (e) para emerger, (n) para emerger con nohup, (b) sólo descargar los paquetes, (f) elegir paquetes nuevamente, (a) quitar: "
   read choice

   #echo
   
   case "${choice}" in
     a|A)
      cancelled
      ;;
     f|F)
      # do nothing - allow next filtering
      ;;
     b|B)
      ebegin "Ejecutando el emerge -f..."
      echo "emerge -f ${packages}" > /tmp/.jemerge.last
      emerge -f ${packages}
      echo
      rm -f /tmp/.jemerge.last
      exit 0
      ;;
     n|N)
      ebegin "Ejecutando emerge con nohup..."
      nohup emerge --oneshot ${packages} &
      echo
      exit 0
      ;;
     e|E)
      ebegin "Ejecutando ${final_emerge_cmd}..."
      echo "${final_emerge_cmd} --oneshot ${packages}" > /tmp/.jemerge.last
      ${final_emerge_cmd} --oneshot ${packages}
      echo
      rm -f /tmp/.jemerge.last
      exit 0
      ;;
     *)
      eerror "Invalid input."
      ;;
   esac
  done
done