#!/usr/bin/env bash

# Copyright (C) 2016-2022 Ole Tange, http://ole.tange.dk and Free
# Software Foundation, Inc.
#
# 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/>
# or write to the Free Software Foundation, Inc., 51 Franklin St,
# Fifth Floor, Boston, MA 02110-1301 USA
#
# SPDX-FileCopyrightText: 2021-2022 Ole Tange, http://ole.tange.dk and Free Software and Foundation, Inc.
# SPDX-License-Identifier: GPL-3.0-or-later

grepq() {
    # grep -q for systems without -q
    grep >/dev/null 2>/dev/null "$@"
}

installer() {
    source="$1"
    script="$2"
    into="$3"
    if grepq $script "$into"; then
	true already installed
    else
	echo $source \`which $script\` >> "$into"
    fi
}

while test $# -gt 0; do
  key="$1"

  case $key in
      -i|--install)
	  installer . env_parallel.bash  "$HOME"/.bashrc
	  installer . env_parallel.sh  "$HOME"/.shrc
	  installer . env_parallel.zsh   "$HOME"/.zshenv
	  installer source env_parallel.ksh "$HOME"/.kshrc
	  installer source env_parallel.mksh "$HOME"/.mkshrc
	  echo $SHELL | grepq /pdksh &&
	      installer . env_parallel.pdksh "$HOME"/.profile
	  echo $SHELL | grepq /ash &&
	      installer . env_parallel.ash "$HOME"/.profile
	  echo $SHELL | grepq /dash &&
	      installer . env_parallel.dash "$HOME"/.profile
	  installer source env_parallel.csh "$HOME"/.cshrc
	  installer source env_parallel.tcsh "$HOME"/.tcshrc
	  mkdir -p "$HOME"/.config/fish
	  grepq env_parallel.fish "$HOME"/.config/fish/config.fish ||
  	    echo '. (which env_parallel.fish)' >> "$HOME"/.config/fish/config.fish
  	  echo 'Installed env_parallel in:'
  	  echo "    " "$HOME"/.bashrc
  	  echo "    " "$HOME"/.shrc
  	  echo "    " "$HOME"/.zshenv
  	  echo "    " "$HOME"/.config/fish/config.fish
  	  echo "    " "$HOME"/.kshrc
  	  echo "    " "$HOME"/.mkshrc
  	  echo "    " "$HOME"/.profile
  	  echo "    " "$HOME"/.cshrc
  	  echo "    " "$HOME"/.tcshrc
  	  exit
      ;;
      *)
  	echo "Unknown option: $key"
      ;;
  esac
  shift # past argument or value
done


cat <<'_EOS'
env_parallel only works if it is a function.

Do this and restart your shell:

bash:  Put this in $HOME/.bashrc:  . `which env_parallel.bash`
       E.g. by doing:  echo '. `which env_parallel.bash`' >> $HOME/.bashrc
       Supports: variables, aliases, functions, arrays

fish:  Put this in $HOME/.config/fish/config.fish:  . (which env_parallel.fish)
       E.g. by doing:
         echo '. (which env_parallel.fish)' >> $HOME/.config/fish/config.fish
       Supports: variables, aliases, functions, arrays

ksh:   Put this in $HOME/.kshrc:  source `which env_parallel.ksh`
       E.g. by doing:  echo 'source `which env_parallel.ksh`' >> $HOME/.kshrc
       Supports: variables, aliases, functions, arrays

mksh:  Put this in $HOME/.mkshrc:  source `which env_parallel.mksh`
       E.g. by doing:  echo 'source `which env_parallel.mksh`' >> $HOME/.mkshrc
       Supports: variables, aliases, functions, arrays

pdksh: Put this in $HOME/.profile:  source `which env_parallel.pdksh`
       E.g. by doing:  echo '. `which env_parallel.pdksh`' >> $HOME/.profile
       Supports: variables, aliases, functions, arrays

zsh:   Put this in $HOME/.zshrc:  . `which env_parallel.zsh`
       E.g. by doing:  echo '. `which env_parallel.zsh`' >> $HOME/.zshenv
       Supports: variables, functions, arrays

ash:   Put this in $HOME/.profile:  . `which env_parallel.ash`
       E.g. by doing:  echo '. `which env_parallel.ash`' >> $HOME/.profile
       Supports: variables, aliases

dash:  Put this in $HOME/.profile:  . `which env_parallel.dash`
       E.g. by doing:  echo '. `which env_parallel.dash`' >> $HOME/.profile
       Supports: variables, aliases

csh:   Put this in $HOME/.cshrc:  source `which env_parallel.csh`
       E.g. by doing:  echo 'source `which env_parallel.csh`' >> $HOME/.cshrc
       Supports: variables, aliases, arrays with no special chars

tcsh:  Put this in $HOME/.tcshrc:  source `which env_parallel.tcsh`
       E.g. by doing:  echo 'source `which env_parallel.tcsh`' >> $HOME/.tcshrc
       Supports: variables, aliases, arrays with no special chars

To install in all shells run:

  env_parallel --install

In a script you need to run this before using env_parallel:

bash:  . `which env_parallel.bash`
ksh:   source `which env_parallel.ksh`
mksh:  source `which env_parallel.mksh`
pdksh: source `which env_parallel.pdksh`
zsh:   . `which env_parallel.zsh`
ash:   . `which env_parallel.ash`
dash:  . `which env_parallel.dash`

For details: see  man env_parallel

_EOS