#!/bin/bash
BASE_URL='http://geolite.maxmind.com/download/geoip/database/'
GEOLITE_COUNTRY_DB='GeoLiteCountry/GeoIP.dat'
GEOLITE_COUNTRY_IPV6_DB='GeoIPv6.dat'
GEOLITE_CITY_DB='GeoLiteCity.dat'
GEOLITE_CITY_IPV6_DB='GeoLiteCityv6-beta/GeoLiteCityv6.dat'

if [ $# -eq 0 ]; then
    echo "usage: geoip-download-databases <output_directory>" >&2
    exit 1
fi

outdir="$1"
tmpdir=$(mktemp -d) || exit 1
trap "rm -rf ${tmpdir}" EXIT QUIT HUP KILL TERM

pushd $tmpdir
wget "${BASE_URL}${GEOLITE_COUNTRY_DB}.gz" || exit 1
wget "${BASE_URL}${GEOLITE_COUNTRY_IPV6_DB}.gz" || exit 1
wget "${BASE_URL}${GEOLITE_CITY_DB}.gz" || exit 1
wget "${BASE_URL}${GEOLITE_CITY_IPV6_DB}.gz" || exit 1
gunzip *

function file_size()
{
    local size
    size=$(stat -c "%s" $1 2>/dev/null)
    if [ -n "${size}" ]; then
	echo ${size}
    else
	echo 0
    fi
}

# 200KB.  The country database should be just over 1MB, while the city database is presently 43MB.
# This is big enough to notice a seriously corrupted download.
MIN_SIZE=$((1024*200))
IPV6_MIN_SIZE=$((1024*40))

if [ $(file_size $(basename ${GEOLITE_COUNTRY_DB})) -gt ${MIN_SIZE} -a \
     $(file_size $(basename ${GEOLITE_CITY_DB}))    -gt ${MIN_SIZE} -a \
     $(file_size $(basename ${GEOLITE_COUNTRY_IPV6_DB})) -gt ${IPV6_MIN_SIZE} -a \
     $(file_size $(basename ${GEOLITE_CITY_IPV6_DB})) -gt ${IPV6_MIN_SIZE} ]; then
    cp -a $(basename ${GEOLITE_COUNTRY_DB}) $(basename ${GEOLITE_CITY_DB}) $(basename ${GEOLITE_COUNTRY_IPV6_DB}) $(basename ${GEOLITE_CITY_IPV6_DB}) "${outdir}"
else
    echo "unable to retrieve databases." >&2
    exit 1
fi
exit 0