#!/bin/bash

output_dirname=$1
input_dirname=$2

# make sure "sort" works the way we expect it to
export LC_ALL=C

rpm_dir=/var/lib/rpm
dpkg_dir=/var/lib/dpkg

bin_dir=`readlink -f $0 | xargs dirname`

dpkg=0
rpm=0

if [ "X${output_dirname}" == "X" ] ; then
	echo "Need to specify output directory. "
	echo "   update_distro <output_dir> [<input_dir>]"
	exit 1
fi


function process_rpm
{
	rpm -q --queryformat="%{NAME} %{VERSION} %{RELEASE} %{ARCH}\n" \
		-a --dbpath ${input_dirname} \
		> ${output_dirname}/packages

	# Use rpm to generate a list like:
	#	firstpkg # firstpkg.list
	#	firstpkg /path/to/Afile1
	#	firstpkg /path/to/Afile2
	#	secondpkg # secondpkg.list
	#	secondpkg /path/to/Bfile1
	#	secondpkg /path/to/Bfile2
	# That list can be ran through "sort -u" to elminate
	# duplicates within each package, and then the leading
	# package names can be stripped off using "sed".  That
	# gives a list that can be piped into swab_testf, which
	# will test each for the existance of each file and
	# generate the pkg.list files.
	rpm -qa --qf "%{NAME} # ${output_dirname}/%{NAME}.list\n[%{NAME} %{FILENAMES}\n]" \
		--dbpath ${input_dirname} | sort -u |
		sed -e 's/[^ ]* //' | ${bin_dir}/swab_testf
}

function process_dpkg
{

	dpkg-query -W \
		--showformat="\${Package} \${Version} 0 \${Architecture}\n" \
		--admindir=${input_dirname} > ${output_dirname}/packages

	ls -d1 ${input_dirname}/info/*.list |
	while read pkg_path ; do
		echo "# ${output_dirname}/"`basename ${pkg_path}`
		cat ${pkg_path}
	done | ${bin_dir}/swab_testf
}


function detect_distro
{
	HOST=`grep 'openSUSE\|Fedora\| SUSE\|Red Hat\|Ubuntu' /etc/issue| sed 's/.*\(openSUSE\|Fedora\| SUSE\|Red Hat\|Ubuntu\).*/\1/'`

	if [ -z "$HOST" ];then
		echo unable to determine host type
		exit 1
	fi

	TEMP=`mktemp`

	if [ "$HOST" = "Ubuntu" ]; then
		NEWEST=10.04
		VER=`cat /etc/issue|head -n1 | awk '{print $2}'`
		dpkg-query -l > $TEMP
		if [ $? != 0 ];then
			echo package listing failed
			exit 1
		fi
	elif [ "$HOST" = "Fedora" ]; then
		NEWEST=11
		VER=`cat /etc/issue|head -n1 | awk '{print $3}'`
		HOST="fedora"
		rpm -qa > $TEMP
		if [ $? != 0 ];then
			echo package listing failed
			exit 1
		fi
	elif [ "$HOST" = "Red Hat" ]; then
		HOST="redhat"
		release_ver=`rpm -q --queryformat "%{VERSION}" redhat-release`
MAJOR="?"
		if [ `echo ${release_ver} | grep 4` ] ; then
			MAJOR="4"
			MINOR=`cat /etc/issue|head -n1 | sed 's/.*\([0-9]\))/\1/'`
		elif [ `echo ${release_ver} | grep 5` ] ; then
			MAJOR="5"
			MINOR=`cat /etc/redhat-release  | sed -e "s/^.*\.//" -e "s/ .*$//"`
		fi
		VER="${MAJOR}.${MINOR}"
	elif [ "$HOST" = " SUSE" ]; then
		NEWEST=11.0
		HOST="SLED"
		VER=`grep SUSE /etc/issue|head -n1 | awk '{print $7}'`
		if [ "$VER" = "10" ];then
			VER=10.2
		fi
		rpm -qa > $TEMP
		if [ $? != 0 ];then
			echo package listing failed
			exit 1
		fi
	elif [ "$HOST" = "openSUSE" ]; then
		NEWEST=11.2
		VER=`grep SUSE /etc/issue|head -n1 | awk '{print $4}'`
		if [ "$VER" = "10" ];then
			VER=10.2
		fi
		rpm -qa > $TEMP
		if [ $? != 0 ];then
			echo package listing failed
			exit 1
		fi
	else
		echo unknown host type -- $HOST
		exit 1
	fi
		
	W=`tail -n1 /proc/kallsyms |awk '{print $1}'|wc -c`
	WIDTH=`echo "($W-1)*4"|bc`

	echo $HOST-$VER-${WIDTH}
}

function regenerate_blob
{
	echo Reading package directory from ${input_dirname}, writing out to ${output_dirname}

	mkdir -p ${output_dirname}  || \
		( echo "Could not create output directory ${output_dirname}" ; exit )

	if [ ${rpm} -eq 1 ] ; then
		echo Looks like an RPM distribution to me...
		
		process_rpm
	fi
	if [ ${dpkg} -eq 1 ] ; then
		echo Looks like a dpkg distribution to me...
		process_dpkg
	fi

	echo ${distro_name} > ${output_dirname}/distro

	blob_file=${distro_dir}/distro.blob

	${bin_dir}/load_distro -d ${output_dirname}

	echo ${md5} > ${md5_file}

}



distro_name=`detect_distro`
echo "Distribution is ${distro_name}"

if [ "X${input_dirname}" != "X" ] ; then
	rpm_dir=${input_dirname}
	dpkg_dir=${input_dirname}
fi

if [ -f ${rpm_dir}/Packages ] ; then
	input_dirname=${rpm_dir}
	rpm=1
else if [ -f ${dpkg_dir}/status ] ; then
	input_dirname=${dpkg_dir}
	dpkg=1
else 
	echo Could not identify distribution.
	exit 1
fi
fi

md5_file=${output_dirname}/md5
md5=`ls -lR ${input_dirname} | md5sum | cut -f 1 -d " " `
existing_md5=`cat ${md5_file} 2> /dev/null`

if [ ! "X${md5}" == "X${existing_md5}" ] ; then
	echo Regenerating
	regenerate_blob
else
	echo Existing cache can be used
fi

rm -f ${output_dirname}/*list