#!/bin/sh

# Copyright 2012 Hewlett-Packard Development Company, L.P.
# All Rights Reserved.
# Copyright 2013 Red Hat, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

set -e

# Download a URL to a local cache
# e.g. cache-url http://.../foo ~/.cache/image-create/foo

url=$1
dest=$2

mkdir -p $(dirname $dest)
tmp=$(mktemp $(dirname $dest)/.download.XXXXXXXX)

if [ -f $dest ] ; then
    time_cond="-z $dest"
    success="Server copy has changed. Using server version of $url"
else
    success="Downloaded and cached $url for the first time"
fi

rcode=$(curl -L -o $tmp -w '%{http_code}' $url $time_cond)
if [ "$rcode" = "200" ] ; then
    echo $success
    mv $tmp $dest
elif [ "$rcode" = "304" ] ; then
    echo "Server copy has not changed. Using locally cached $url"
    rm -f $tmp
else
    echo "Server returned an unexpected response code. [$rcode]"
    rm -f $tmp
    exit 1
fi