#!/bin/bash

#
# pdfattach --- embed specified file(s) in a specified PDF file
# Requires pdfLaTeX and attachfile.sty package to run
# Returns 0 on success or >0 on error
#
# Written by Tigran Aivazian <tigran@bibles.org.uk>
#

progname=$(basename $0)

function usage()
{
	echo "Usage: $progname -o file.pdf file1.djvu [file2.mp3] ..."
	exit 1
}

if (! getopts ":o:" opt); then
	echo "$progname: Missing options." >&2
	usage
fi

if ! type pdflatex > /dev/null 2>&1 ; then
	echo "$progname: pdfLaTeX program is required." >&2
	exit 1
fi

if ! kpsewhich attachfile.sty > /dev/null 2>&1 ; then
	echo "$progname: attachfile.sty package is required." >&2
	exit 1
fi

declare outfile=""
declare -a infiles=()
declare -i infcount=0 outfcount=0

while getopts ":o:" opt; do
	case $opt in
	o)
		outfile=$(readlink -f "$OPTARG")
		((outfcount++))
		;;
	\?)
		echo "$progname: Invalid option: -$OPTARG" >&2
		usage
		;;
	:)
		echo "$progname: Option -$OPTARG requires an argument." >&2
		usage
		;;
	esac
done

shift $((OPTIND-1))

numargs=$#
for ((i=1 ; i <= $numargs ; i++))
do
	fullname=$(readlink -f "$1")
	if [ ! -f "$fullname" ] ; then
		echo "$progname: file \"$fullname\" does not exist" >&2
		usage
	fi
	infiles[$infcount]="$fullname"
	((infcount++))
	shift
done

if ((infcount == 0)) ; then
	echo "$progname: No input file(s) specified." >&2
	usage
fi

if ((outfcount != 1)) ; then
	echo "$progname: One (and only one) output file must be specified." >&2
	usage
fi

workdir=$(mktemp --tmpdir -d pdfattach.XXXXXX)
cd $workdir
> tmp.tex
echo -E "\documentclass{book}" >> tmp.tex
echo -E "\usepackage{attachfile}" >> tmp.tex
echo -E "\begin{document}" >> tmp.tex
echo -E "\pagestyle{empty}" >> tmp.tex
for ((i = 0 ; i < ${#infiles[*]} ; i++));
do
	echo "\attachfile{${infiles[$i]}}" >> tmp.tex
done
echo -E "\end{document}" >> tmp.tex
pdflatex -halt-on-error tmp.tex > /dev/null && mv tmp.pdf "$outfile"
cd - > /dev/null
rm -rf $workdir