#!/usr/bin/env bash

if [[ ( ${BASH_VERSINFO[0]} == 4 && ${BASH_VERSINFO[1]} > 1 ) || ${BASH_VERSINFO[0]} > 4 ]] ; then
	shopt -s compat41
fi
set -e


ASTTOPDIR=${ASTTOPDIR:-.}
export make=`sed -n -r -e "s/^MAKE\s*=\s*//gp" ${ASTTOPDIR}/makeopts`

getvar() {
	$make --quiet --no-print-directory -f- <<EOF
include ${ASTTOPDIR}/makeopts
all:
	@echo "\$($1)"
EOF
}

XMLSTARLET=`getvar XMLSTARLET`
ASTMODDIR=`getvar ASTMODDIR`
cache_dir=`getvar EXTERNALS_CACHE_DIR`
DOWNLOAD_TO_STDOUT=`getvar DOWNLOAD_TO_STDOUT`
HOST_CPU=`getvar HOST_CPU`
INSTALL=`getvar INSTALL`

module_name=${1%%-*}
variant=${1##*-}

if [[ "${variant}" = "${module_name}" ]] ; then
	unset variant
fi

if [[ -z ${module_name} ]] ; then
	echo "You must supply a module name."
	exit 64
fi

tmpdir=$(mktemp -d)
if [[ -z "${tmpdir}" ]] ; then
	echo "${module_name}: Unable to create temporary directory."
	exit 1
fi
trap "rm -rf ${tmpdir}" EXIT

if [[ -z "${ASTMODDIR}" ]] ; then
	echo "${module_name}: Unable to parse ${ASTTOPDIR}/makeopts."
	exit 1
fi

if [[ "${XMLSTARLET}" = ":" ]] ; then
	echo "${module_name}: The externals downloader requires xmlstarlet to be installed."
	exit 1
fi

if [[ -z ${cache_dir} ]] ; then
	cache_dir=${tmpdir}
fi

version=$(${ASTTOPDIR}/build_tools/make_version ${ASTTOPDIR})
if [[ ! ${version} =~ ^(GIT-)?(certified/)?([^.-]+)[.-].* ]] ; then
	echo "${module_name}: Couldn't parse version ${version}"
	exit 1
fi
major_version=${BASH_REMATCH[3]}

if [[ "${major_version}" == "master" ]] ; then
	echo "${module_name}: External module downloading is not available in the 'master' git branch.  Please disable in menuselect and download manually."
	exit 1
fi

major_version=${major_version}.0

if [[ "${HOST_CPU}" = "x86_64" ]] ; then
	host_bits=64
else
	host_bits=32
fi

if [[ -z "${variant}" ]] ; then
	variants=$(${XMLSTARLET} sel -t -m "/menu/category/member[@name = '${module_name}']/member_data/downloader/variants/variant" -v "@tag" -n ${ASTTOPDIR}/menuselect-tree || :)
	member_name=${module_name}
	for tag in ${variants} ; do
		condition=$(${XMLSTARLET} sel -t -v "/menu/category/member[@name = '${module_name}']/member_data/downloader/variants/variant[@tag = '${tag}']/@condition" ${ASTTOPDIR}/menuselect-tree || :)
		variant=$(eval "if $condition ; then echo $tag ; fi")
		if [[ -n "${variant}" ]] ; then
			break
		fi
	done
else
	member_name=${module_name}${variant:+-${variant}}
fi

full_name=${module_name}${variant:+-${variant}}
variant_manifest=manifest${variant:+-${variant}}.xml

# Override the remote base for all packages
# useful for testing
remote_url=${REMOTE_BASE:+${REMOTE_BASE}/asterisk-${major_version}/x86-${host_bits}}

if [[ -z "${remote_url}" ]] ; then
	remote_url=$(${XMLSTARLET} sel -t -v "/menu/category/member[@name = '${member_name}']/member_data/downloader/@remote_url" ${ASTTOPDIR}/menuselect-tree || :)
	if [[ -n "${remote_url}" ]] ; then
		remote_url="${remote_url}/asterisk-${major_version}/x86-${host_bits}"
	else
		directory_name=$(${XMLSTARLET} sel -t -v "/menu/category/member[@name = '${member_name}']/member_data/downloader/@directory_name" ${ASTTOPDIR}/menuselect-tree || :)
		remote_url="http://downloads.digium.com/pub/telephony/${directory_name:-${module_name}}/asterisk-${major_version}/x86-${host_bits}"
	fi
fi

version_convert() {
	local v=${1##*_}
	if [[ ${v} =~ ([0-9]+)[.]([0-9]+)[.]([0-9]+) ]] ; then
		v=$(( ${BASH_REMATCH[1]}<<18 | ${BASH_REMATCH[2]}<<9 | ${BASH_REMATCH[3]} ))
	fi
	echo ${v}
}

${DOWNLOAD_TO_STDOUT} ${remote_url}/${variant_manifest} > ${tmpdir}/${variant_manifest} || {
	echo "${full_name}: Unable to fetch ${remote_url}/${variant_manifest}"
	exit 1
}

rpv=$(${XMLSTARLET} sel -t -v "/package/@version" ${tmpdir}/${variant_manifest})
rpvi=$(version_convert ${rpv})
echo "${full_name}: Remote package version ${rpv} (${rpvi})"

module_dir=${full_name}-${rpv}-x86_${host_bits}
tarball=${module_dir}.tar.gz

export need_install=0

if [[ -f ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml ]] ; then
	package_arch=$(${XMLSTARLET} sel -t -v "/package/@arch" ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml)
	ipv=$(${XMLSTARLET} sel -t -v "/package/@version" ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml)
	package_variant=$(${XMLSTARLET} sel -t -v "/package/@variant" ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml || :)
	ipvi=$(version_convert ${ipv})
	ip_major=${ipv%_*}
	echo "${full_name}: Installed package version ${ipv} (${ipvi})"
	if [[ "${ip_major}" != "${major_version}" || "${package_arch}" != "x86_${host_bits}" || "${package_variant}" != "${variant}" ]] ; then
		echo "${full_name}: The installed package is not for this version of Asterisk.  Reinstalling."
		need_install=1
	elif [[ ${rpvi} > ${ipvi} ]] ; then
		echo "${full_name}: A newer package is available"
		need_install=1
	else
		sums=$(${XMLSTARLET} sel -t -m "//file" -v "@md5sum" -n ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml)
		for sum in ${sums} ; do
			install_path=$(${XMLSTARLET} sel -t -v "//file[@md5sum = '${sum}']/@install_path" ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml )
			executable=$(${XMLSTARLET} sel -t -v "//file[@md5sum = '${sum}']/@executable" ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml || : )
			f=${DESTDIR}$(eval echo ${install_path})
			if [[ ! -f ${f} ]] ; then
				echo Not found: ${f}
				need_install=1
				break
			else
				if [[ "$executable" = "yes" ]] ; then
					# There are easier ways of doing this (objcopy --dump-section) but not in older bunutils
					length_offset=$(objdump -h $f | sed -n -r -e "s/^\s+[0-9]+\s+.ast_manifest\s+([0-9a-fA-F]+)\s+[0-9a-fA-F]+\s+[0-9a-fA-F]+\s+([0-9a-fA-F]+)\s+.*$/0x\1 0x\2/p")
					tags=$($(eval 'printf "dd if=$f bs=1 count=%d skip=%d\n" $length_offset') 2>/dev/null)
					if [[ -n "${tags}" && "${tags}" != "${module_name},${variant},${rpv}" ]] ; then
						echo Tag mismatch: ${f} File: "${tags}" Manifest: "${module_name},${variant},${rpv}"
						need_install=1
						break
					fi
				fi

				cs=$(${MD5} ${f} | cut -b1-32)
				if [[ "${cs}" !=  "${sum}" ]] ; then
					echo Checksum mismatch: ${f}
					need_install=1
					break
				fi
			fi
		done
	fi
else
	need_install=1
fi

if [[ ${need_install} == 1 ]] ; then
	if [[ ( -n "${ipvi}" ) && ${ipvi} > ${rpvi} ]] ; then
		echo "${full_name}: Installed package is newer than that available for download."
		exit 0
	fi
else
	echo "${full_name} is up to date."
	exit 0;
fi

need_download=1
if [[ -f ${cache_dir}/${full_name}.manifest.xml ]] ; then
	cpv=$(${XMLSTARLET} sel -t -v "/package/@version" ${cache_dir}/${full_name}.manifest.xml)
	cpvi=$(version_convert ${cpv})
	echo "${full_name}: Cached package version ${cpv} (${cpvi})"
	if [[ ${cpvi} == ${rpvi} && ( -f ${cache_dir}/${tarball} ) ]] ; then
		echo "${full_name}: Cached version is available."
		need_download=0
	fi
fi

if [[ ${need_download} = 1 ]] ; then
	echo "${full_name}: Downloading ${remote_url}/${tarball} to ${cache_dir}/${tarball}"
	${DOWNLOAD_TO_STDOUT} ${remote_url}/${tarball} > ${cache_dir}/${tarball} || {
		echo "${full_name}: Unable to fetch ${remote_url}/${tarball}"
		exit 1
	}
	cp ${tmpdir}/${variant_manifest}  ${cache_dir}/${full_name}.manifest.xml
fi

tar -xzf ${cache_dir}/${tarball} -C ${cache_dir}
trap "rm -rf ${cache_dir}/${module_dir} ; rm -rf ${tmpdir}" EXIT

echo "${full_name}: Installing."

if [[ $EUID == 0 ]] ; then
	install_params="-g 0 -o 0"
fi

names=$(${XMLSTARLET} sel -t -m "//file" -v "@name" -n ${cache_dir}/${module_dir}/manifest.xml)
for name in ${names} ; do
	source_path=${cache_dir}/${module_dir}/${name}
	install_path=$(${XMLSTARLET} sel -t -v "//file[@name = '${name}']/@install_path" ${cache_dir}/${module_dir}/manifest.xml)
	install_path=${DESTDIR}$(eval echo ${install_path})
	executable=$(${XMLSTARLET} sel -t -v "//file[@name = '${name}']/@executable" ${cache_dir}/${module_dir}/manifest.xml || :)
	if [[ "${executable}" = "yes" ]] ; then
		mode=0755
	else
		mode=0644
	fi

	${INSTALL} -Dp ${install_params} -m ${mode} ${source_path} ${install_path}

done
${INSTALL} -Dp ${install_params} --mode=0644 ${cache_dir}/${module_dir}/manifest.xml ${DESTDIR}${ASTMODDIR}/${module_name}.manifest.xml

echo "${full_name}: Installed."
