#!/bin/bash
# requires: wget, yum-utils, timeout, md5sum
set -e
set -o pipefail

_here=`dirname $(realpath $0)`
apt_sync="${_here}/apt-sync.py" 

MAX_RETRY=${MAX_RETRY:-"3"}
DOWNLOAD_TIMEOUT=${DOWNLOAD_TIMEOUT:-"1800"}

BASE_URL="http://download.virtualbox.org/virtualbox"
BASE_PATH="${TUNASYNC_WORKING_DIR}"

RPM_PATH="${BASE_PATH}/rpm"
APT_PATH="${BASE_PATH}/apt"

EL_VERSIONS=("5" "6" "7" "8")

mkdir -p ${RPM_PATH} ${APT_PATH}

# === download rhel packages ====
cache_dir="/tmp/yum-virtualbox-el-cache/"
cfg="/tmp/virtualbox-el-yum.conf"
cat <<EOF > ${cfg}
[main]
keepcache=0

EOF

for releasever in ${EL_VERSIONS[@]}; do
cat <<EOF >> ${cfg}
[el${releasever}]
name=Oracle Linux / RHEL / CentOS-5 / x86_64 - VirtualBox
baseurl=${BASE_URL}/rpm/el/$releasever/x86_64
repo_gpgcheck=0
gpgcheck=0
enabled=1
EOF
done

if [[ -z ${DRY_RUN:-} ]]; then
	reposync -c $cfg -d -p ${RPM_PATH} -e $cache_dir
	for releasever in ${EL_VERSIONS[@]}; do
		createrepo --update -v -c $cache_dir -o ${RPM_PATH}/el$releasever ${RPM_PATH}/el$releasever
	done
fi
rm $cfg

# === download deb packages ====

"$apt_sync" "${BASE_URL}/debian" @debian-current,@ubuntu-lts contrib,non-free amd64,i386 "$APT_PATH"
echo "Debian and ubuntu finished"

# === download standalone packages ====

timeout -s INT 30 wget ${WGET_OPTIONS:-} -q -O "/tmp/index.html" "${BASE_URL}/"
timeout -s INT 30 wget ${WGET_OPTIONS:-} -q -O "${BASE_PATH}/LATEST.TXT" "${BASE_URL}/LATEST.TXT"

for((major=4;major<=6;major++));do
	LATEST_VERSION=$(grep -P -o "\"$major\.[\\d\\.]+/\"" -r /tmp/index.html|tail -n 1)
	LATEST_VERSION=${LATEST_VERSION%/\"}
	LATEST_VERSION=${LATEST_VERSION#\"}
	[[ -z "$LATEST_VERSION" ]] && continue

	LATEST_PATH="${BASE_PATH}/${LATEST_VERSION}"

	mkdir -p ${LATEST_PATH}
	timeout -s INT 30 wget ${WGET_OPTIONS:-} -q -O "${LATEST_PATH}/MD5SUMS" "${BASE_URL}/${LATEST_VERSION}/MD5SUMS"
	timeout -s INT 30 wget ${WGET_OPTIONS:-} -q -O "${LATEST_PATH}/SHA256SUMS" "${BASE_URL}/${LATEST_VERSION}/SHA256SUMS"

	while read line; do
		read -a tokens <<< $line
		pkg_checksum=${tokens[0]}
		filename=${tokens[1]}
		filename=${filename/\*/}

		dest_filename="${LATEST_PATH}/${filename}"
		pkg_url="${BASE_URL}/${LATEST_VERSION}/${filename}"

		declare downloaded=false

		if [[ -f ${dest_filename} ]]; then
			echo "${pkg_checksum}  ${dest_filename}" | md5sum -c - && {
				downloaded=true
				echo "Skipping ${filename}"
			}
		fi
		for retry in `seq ${MAX_RETRY}`; do
			[[ $downloaded == true ]] && break
			rm ${dest_filename} || true
			echo "downloading ${pkg_url} to ${dest_filename}"
			if [[ -z ${DRY_RUN:-} ]]; then
				timeout -s INT "$DOWNLOAD_TIMEOUT" wget ${WGET_OPTIONS:-} -N -c -q -O ${dest_filename} ${pkg_url} && {
					# two space for md5sum/sha1sum/sha256sum check format
					echo "${pkg_checksum}  ${dest_filename}" | md5sum -c - && downloaded=true
				}
			else
				downloaded=true
			fi
		done
		if [[ $downloaded == false ]];then
			echo "failed to download ${pkg_url} to ${dest_filename}"
			exit 1
		fi

	done < "${LATEST_PATH}/MD5SUMS"
	echo "Virtualbox ${LATEST_VERSION} finished"
done

echo "Linking the latest releases"
LATEST_VERSION=`cat "${BASE_PATH}/LATEST.TXT"`
for filename in ${BASE_PATH}/${LATEST_VERSION}/*.*; do
	case $filename in
		*Win.exe)
			ln -sf "${filename}" "${BASE_PATH}/virtualbox-Win-latest.exe"
			;;
		*OSX.dmg)
			ln -sf "${filename}" "${BASE_PATH}/virtualbox-osx-latest.dmg"
			;;
	esac
done