#!/bin/sh
# ====================[ emacso                             ]====================
#                     [ Time-stamp: "2008-08-21 14:37:06 leycec" ]             
#
# An "emacsclient"-enabled shell script for opening new Emacs processes as
# client frames of one master Emacs process - a little stabler and more feature-
# filled than the "emacs.bash" and "emacs.csh" shell scripts pre-bundled with
# Emacs.
#
# --------------------( SYNOPSIS                           )--------------------
# emacso [options] file...
#
#       options
# -h, --help   Show this help.
# -w, --wait   Wait for Emacs to exit before exiting this script.
#
# --------------------( DESCRIPTION                        )--------------------
# Unlike the default "edit.bash" script shipping with Emacs, this script either
# {a} returns immediately (non-blocking) or
# {b} waits for you to complete editing before returning (blocking).
#
# By default, this script returns immediately. (This permits this script to be
# used as a drop-in replacement for "emacs" via the $EDITOR shell variable. See
# below, for details.)
# 
# --------------------( INSTALLATION                       )--------------------
# # Move this file to a path in your $PATH.
# mv emacso /usr/local/bin
#
# # Point your $EDITOR shell variable to this file.
# export EDITOR=/usr/local/bin/emacso
#
# # Optionally, make a shell alias to this file.
# alias e="emacso"
#
# --------------------( XEMACS                             )--------------------
# This script does not, as yet, support XEmacs - which, rather than use the
# "emacsclient" binary and protocol for XEmacs client/server management, uses
# "gnuclient". (Adding implicit support for XEmacs isn't difficult, of course;
# it simply isn't supported, yet. Clean patches, on that front, are happily
# welcome!)
#
# --------------------( MUTT                               )--------------------
# Mutt is an e-mail client.
# 
# Mutt will "not quite" work out of the box, with this script. This script is
# non-blocking, by default; Mutt, on the other, requires that your $EDITOR be
# blocking (so that, clearly, it can be notified of your having completed
# editing for the mail it passed your $EDITOR).
#
# This is correctable, as follows:
#
#   # Open your user's "muttrc" file for editing.
#   emacso ~/.mutt/muttrc
#
#   # Point the editor variable to this file (rather than letting it depend on
#   # the default value of the $EDITOR shell variable).
#   set editor="/usr/local/bin/emacso --wait"
#
# --------------------( CHANGELOG                          )--------------------
# [2007-05-30] 0.0.1: Creation.

# ....................{ CONFIGURATION                      }....................
#FIXME: Add XEmacs support, here.
EMACSCLIENT_COMMAND="emacsclient"
EMACS_COMMAND="emacs --debug-init"

# ....................{ USAGE                              }....................
SCRIPT_NAME=$(basename "$0")

echo_usage_error() {
  echo_usage
  exit 1
}

echo_usage_noerror() {
  echo_usage
  exit 0
}

echo_usage() {
  echo "Usage: ${SCRIPT_NAME} [options] file...
             options
  -h, --help   Show this help.
  -w, --wait   Wait for Emacs to exit before exiting this script."
}

# ....................{ OPTIONS                            }....................
OPTIONS=$(getopt --unquoted --longoption 'wait,help' --options '+w,h' --shell sh -- "${@}")
[ $? = 0 ] || echo_usage_error

set -- $OPTIONS

while [ $# -gt 0 ]; do
  case "$1" in
    --help) echo_usage_noerror;;
    -h)     echo_usage_noerror;;
    --wait) IS_WAITING="1"; shift;;
    -w)     IS_WAITING="1"; shift;;
    --)     shift; break;;
    -*)     echo_usage_error;;
    *)      break;;
  esac
done

FILES_TO_EDIT="$@"

# ....................{ COMMANDS                           }....................
run_emacs() {
  if [ -n "$IS_WAITING" ]; then
    echo "emacso: running $EMACS_COMMAND... (waiting)" 1>&2
    $EMACS_COMMAND $FILES_TO_EDIT
  else
    echo "emacso: running $EMACS_COMMAND..." 1>&2
    $EMACS_COMMAND $FILES_TO_EDIT &
  fi
}

run_emacsclient() {
  if [ -n "$IS_WAITING" ]; then
    echo "emacso: running $EMACSCLIENT_COMMAND... (waiting)" 1>&2
    $EMACSCLIENT_COMMAND $FILES_TO_EDIT
  else
    echo "emacso: running $EMACSCLIENT_COMMAND..." 1>&2
    $EMACSCLIENT_COMMAND --no-wait $FILES_TO_EDIT
  fi

  [ $? = 0 ] || run_emacs
}

# ....................{ EMACSO                             }....................
if [ -n "${DISPLAY}" ]; then
  # Do not just test if these files are sockets. On some systems
  # ordinary files or fifos are used instead. Just see if they exist.
  if [ -e "${HOME}/.emacs_server" -o -e "/tmp/emacs${UID}/server" ]
  then run_emacsclient
  else run_emacs
  fi
else
  if jobs %emacs 2>/dev/null
  then echo "$(pwd)" $FILES_TO_EDIT >| ${HOME}/.emacs_args && fg %emacs
  else run_emacs
  fi
fi

exit $?

# --------------------( COPYRIGHT AND LICENSE              )--------------------
# The information below applies to everything in this distribution,
# except where noted.
# 
# Copyleft 2008 by B.w.Curry.
# 
#   http://www.raiazome.com
# 
# This file 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 file 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 file; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.