#! /bin/sh
# Zgrep - Grep wrapper for compressed files.
# Copyright (C) 2008, 2009 Antonio Diaz Diaz.
#
# This script is free software: you have unlimited permission
# to copy, distribute and modify it.

LC_ALL=C
export LC_ALL
args=
have_pat=0
list=0
no_name=0
two_hyphens=0

# Loop over args until pattern is found
while [ x"$1" != x ] ; do

	case "$1" in
	--help | --he* | -h)
		echo "Zgrep - Grep wrapper for compressed files."
		echo
		echo "Zgrep is a wrapper script around the grep command that allows"
		echo "transparent search on any combination of compressed and non-compressed"
		echo "files. If any given file is compressed, its uncompressed content is"
		echo "used. If a given file does not exist, zgrep tries the compressed file"
		echo "names corresponding to the supported compressors."
		echo "The supported compressors are gzip, bzip2, lzip and xz."
		echo
		echo "Usage: $0 [OPTIONS] [GREP_OPTIONS] PATTERN [FILES]"
		echo
		echo "GREP_OPTIONS are passed directly to grep."
		echo "The exit status from grep is preserved."
		echo
		echo "Options:"
		echo "  -h, --help          display this help and exit"
		echo "  -V, --version       output version information and exit"
		echo
		echo "Report bugs to zutils-bug@nongnu.org"
		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
		exit 0 ;;
	--version | --ve* | -V)
		echo "Zgrep VERSION"
		echo "Copyright (C) 2009 Antonio Diaz Diaz."
		echo "This script is free software: you have unlimited permission"
		echo "to copy, distribute and modify it."
		exit 0 ;;
	-[drRzZ] | --di* | --exc* | --inc* | --nu* | --rec*)
		echo "$0: option $1 not supported"
		exit 1 ;;
	-e?* | -f?* | --file=* | --reg*=*)
		args="${args} $1"; have_pat=1 ;;
	-e | -f | --file | --reg*)
		args="${args} $1 $2"; shift; have_pat=1 ;;
	--*=*)
		args="${args} $1" ;;
	-[ABCDm] | --af* | --be* | --binary-* | --con* | --de* | --[lm]a*)
		args="${args} $1 $2"; shift ;;
	-l | --files-with-*)
		args="${args} $1"; list=1 ;;
	-h | --no-f*)
		args="${args} $1"; no_name=1 ;;
	--)
		shift ; two_hyphens=1 ; break ;;
	-?*)
		args="${args} $1" ;;
	 *)
	 	if [ ${have_pat} = 0 ]; then args="${args} $1"; have_pat=1
		else break
		fi ;;
	esac
	shift
done

if [ ${have_pat} = 0 ]; then
	echo "$0: Pattern not found; use --help for usage." 1>&2
	exit 1
fi

retval=0
for i in "$@" ; do
	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
	else
		if [ -f "$i" ]; then
			case "$i" in
			*.gz | *.tgz)
				prog="gzip -cdfq" ;;
			*.bz2 | *.tbz | *.tbz2)
				prog="bzip2 -cdfq" ;;
			*.lz | *.tlz)
				prog="lzip -cdfq" ;;
			*.xz | *.txz)
				prog="xz -cdfq" ;;
			*)
				prog=cat ;;
			esac
		elif [ -f "$i.gz" ];  then i="$i.gz" ;  prog="gzip -cdfq"
		elif [ -f "$i.bz2" ]; then i="$i.bz2" ; prog="bzip2 -cdfq"
		elif [ -f "$i.lz" ];  then i="$i.lz" ;  prog="lzip -cdfq"
		elif [ -f "$i.xz" ];  then i="$i.xz" ;  prog="xz -cdfq"
		else
			echo "$0: File \"$i\" not found or not a regular file" 1>&2
			if [ ${retval} = 0 ]; then retval=1 ; fi
			continue
		fi
		if [ ${list} = 1 ]; then
			${prog} -- "$i" | grep ${args} 2>&1 > /dev/null && echo "$i"
			r=$?
		elif [ $# = 1 ] || [ ${no_name} = 1 ]; then
			${prog} -- "$i" | grep ${args}
			r=$?
		else
			j=`printf "%s" "$i" | sed 's/\\\\/\\\\\\\\/g'`
			j=`printf "%s" "$j" | sed 's/|/\\\\|/g'`
			j=`printf "%s" "$j" | sed 's/&/\\\\&/g'`
			j=`printf "%s" "$j" | tr '\n' ' '`
			${prog} -- "$i" | grep ${args} | sed "s|^|${j}:|"
			r=$?
		fi
		[ $r != 0 ] && retval="$r"
	fi
done

exit ${retval}