#!/bin/bash

#GNANO - gpg-enabled nano
#gnano enables you to edit a textfile encrypted for some recipients without outputting to cleartext the content (actually it outputs it in a tempfile which permissions are 600, I am working on yhis issue)

if [[ -z $1 ]]; then
	echo "FILE NOT SPECIFIED, EXITING!"
	exit 1
fi

#check program prerequisites:
hash vipe 2>/dev/null || { echo >&2 "I require vipe but it's not installed. It's part of the package morutils, under debian-like systems: 'apt-get install moreutils' Aborting."; exit 1; }
hash gpg 2>/dev/null || { echo >&2 "I require gpg but it's not installed. Aborting."; exit 1; }

#define tempfile
tempfile="/tmp/test2.temp"

#define empty variables
argument=""
recipients=""
new=0

#preparing tempfile
if [ -f $tempfile ] ; then
    rm $tempfile
fi
touch $tempfile
chmod 600 $tempfile

#manage options without getopts
option=$1
argument=$2
if [ "$argument" = "" ]; then
	argument=$option
fi

#OPTIONS:
if [[ $option = "--list" ]] || [[ $option = "-l" ]]; then
	echo "RECIPIENTS:"
	gpg --batch --list-only --no-default-keyring --secret-keyring /dev/null $argument
        exit 1
fi
if [[ $option = "--help" ]] || [[ $option = "-h" ]]; then
        echo "Usage: gnano [OPTIONS] FILE"
	echo ""
	echo "Option	GNU long option		Meaning"
	echo "-l	--list			Lists the recipients of the encrypted file"
	echo "-h	--help			Outputs this help"
	echo "-n	--new			Creates a new encrypted file"
	echo "no options			giving only a filename the program decyphers the file, edits it, and recyphers it with the correct recipients"
	exit 1
fi
if [[ $option = "--new" ]] || [[ $option = "-n" ]]; then
	new=1
	echo "STARTING CREATION OF NEW FILE:"
	echo "your is the task to retrieve the keys or emails of the recipients, I can't do it"
	read -p "enter new filename: " argument
	if [ -f $argument ]; then
		echo "FILE EXISTS! EXITING!"
		exit 1
	fi
	read -p "enter recipients key IDs separated by commas: " newrecipients
fi

#LOOP FOR EXISTING FILE:
if [[ $new -eq "0" ]]; then
        if [ ! -f $argument ]; then
                echo "FILE NOT FOUND, EXITING"
                exit 1
        fi

	cp $argument $argument"_BCK"

	gpg --batch --list-only --no-default-keyring --secret-keyring /dev/null $argument &> $tempfile
	cat $tempfile | grep "gpg: encrypted" | awk '{print $8}' | sed 's/\,//g' > $tempfile
	sleep 0.5

	while read recipient; do
		echo $recipient
		recipients+="-r $recipient "
	done <$tempfile

	if [[ $recipients = "" ]]; then
		echo "ERROR retrieving recipients, known issue, retry!"
		exit 1
	fi
	gpg -d $argument | EDITOR=nano vipe | gpg --batch --yes -e $recipients -o $argument

fi

#LOOP FOR NEW FILE:
if [[ $new -eq "1" ]]; then
	for newrcpt in $(echo $newrecipients | tr "," "\n")
	do
		recipients+="-r $newrcpt "
	done
	nano $tempfile
	cat $tempfile | gpg --batch --yes -e $recipients -o $argument
	rm $tempfile
	echo ""
	echo "DONE!"
	exit 1
fi

#clearing tempfile:
rm $tempfile