#!/bin/bash

set -eu

[ -n "$ARCH" ]
[ -n "$TARGET_ROOT" ]

if [ 'amd64' = "$ARCH" ] ; then
    ARCH="x86_64"
fi

if [ 'i386' = "$ARCH" ] ; then
    ARCH="i586"
fi

DIB_CLOUD_IMAGES=${DIB_CLOUD_IMAGES:-http://download.opensuse.org/repositories/Cloud:/Images/images/}
DIB_RELEASE=${DIB_RELEASE:-13.1}
# FIXME: Hard coded build numbers, versions, etc.
BASE_IMAGE_NAME=${BASE_IMAGE_NAME:-openSUSE-$DIB_RELEASE-OpenStack-Guest.$ARCH}

if [ -z "$DIB_OFFLINE" ] ; then
    # XXX: Try to extract the filename of the current built from the index
    # page. As there is one built available in the repo at a given time, this
    # should work. This is a tempoary workaround until the fix for
    # https://bugzilla.novell.com/show_bug.cgi?id=853882 is deployed
    echo "Looking up current built of Base Image ($BASE_IMAGE_NAME):"
    BASE_IMAGE_FILE=${BASE_IMAGE_FILE:-$(curl $DIB_CLOUD_IMAGES | \
            sed -n "s/^.*\<a\ href\=\"\($BASE_IMAGE_NAME.*\.tbz\)\".*$/\1/p")}
    if [ -n "$BASE_IMAGE_FILE" ]; then
        echo "Using base image: $DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE"
    else
        echo -e "Failed to extract image file name from $DIB_CLOUD_IMAGES" \
                "\nPlease set BASE_IMAGE_FILE manually and retry."
        exit 1
    fi
else
    BASE_IMAGE_FILE=${BASE_IMAGE_FILE:-$BASE_IMAGE_NAME-0.0.1-Build6.1.tbz}
fi

# FIXME: either check the checksums into git or verify the signature
# on the checksums. We should not be trusting checksums we download
# over HTTP
SHA256SUMS=${SHA256SUMS:-$DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE.sha256}
CACHED_FILE=$DIB_IMAGE_CACHE/$BASE_IMAGE_FILE

if [ -n "$DIB_OFFLINE" -a -f "$CACHED_FILE" ] ; then
    echo "Not checking freshness of cached $CACHED_FILE."
else
    echo "Fetching Base Image"
    $TMP_HOOKS_PATH/bin/cache-url $SHA256SUMS $DIB_IMAGE_CACHE/SHA256SUMS.openSUSE.$DIB_RELEASE.$ARCH
    $TMP_HOOKS_PATH/bin/cache-url $DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE $CACHED_FILE
    pushd $DIB_IMAGE_CACHE
    grep "$BASE_IMAGE_FILE" SHA256SUMS.openSUSE.$DIB_RELEASE.$ARCH | sha256sum --check -
    popd
fi
# Extract the base image (use --numeric-owner to avoid possible UID/GID mismatch
# between image tarball and host OS)
sudo tar -C $TARGET_ROOT --numeric-owner -xjf $DIB_IMAGE_CACHE/$BASE_IMAGE_FILE