#!/bin/sh

# grep wrapper to look into PDF files
# supports -i, -c, -v options
# depends on pdftotext

# known bugs:
# FIXED		1. does not suppot spaces in the pattern
#		2. does not support grep -r
# WONTFIX	3. does not support grep -f (it is used to keep pattern)

function usage() {
	echo `basename $0`' <grep options> <pattern> <list of pdf files>'
}

if [ $# -lt 2 ] ; then
	usage
	exit -1
fi

grepoptions=''
patternfile="/tmp/pdfgrep-$$"

while [ $# -gt 1 ] ; do
	a="$1"
	if [ ${a:0:1} == '-' ] ; then
		grepoptions="$grepoptions $a"
		shift
		continue
	else # first non-option argument
		echo "$a" > "$patternfile"
		shift
		break
	fi
done

# --color=always is recommended as default
command="egrep $grepoptions -f $patternfile"

N=$#
for f in "$@" ; do
	# ignore non-PDF files
	if (file "$f"|grep PDF>/dev/null) ; then
		if [ $N -gt 1 ] ; then
			( pdftotext "$f" - | $command ) | \
			sed "s/^/$f:/"
		else
			pdftotext "$f" - | $command
		fi
	fi
done

rm "$patternfile"