#!/usr/bin/env bash

set -e

VERSION=${VERSION:-v3.4.4}

PREFIX_DIR=/usr/local
BIN_DIR=${PREFIX_DIR}/bin

APP=etcd

APP_PREFIX_DIR=${PREFIX_DIR}/${APP}
APP_DEST_DIR=${APP_PREFIX_DIR}/${VERSION}
APP_CURRENT=${APP_PREFIX_DIR}/current

OS=
if [[ $OSTYPE =~ linux ]]; then
    OS=linux
elif [[  $OSTYPE =~ darwin ]]; then
    OS=darwin
else
    echo unknown os: $OSTYPE
    exit 1
fi

ARCH=
if [[ $(uname -m) == x86_64 ]]; then
    ARCH=amd64
else
    echo arch not yet supported: $(uname -m)
    exit 1
fi
URL=https://github.com/etcd-io/etcd/releases/download/${VERSION}/etcd-${VERSION}-${OS}-${ARCH}.tar.gz

[[ -d ${APP_DEST_DIR} ]] || sudo mkdir -p ${APP_DEST_DIR}

TMP_DIR=
if [[ ! -d ${APP_DEST_DIR}/bin ]]; then
    TMP_DIR=$(mktemp --directory)
    DEST_FILE=$TMP_DIR/${APP}.tar.gz
    echo downloading ${APP} ${VERSION} to temp directory ${TMP_DIR}
    curl --silent --location --output ${DEST_FILE} ${URL}

    sudo tar xf ${DEST_FILE} --directory ${APP_DEST_DIR} --strip-components 1
    sudo chown --recursive root:root ${APP_DEST_DIR}
else
    echo ${APP} ${VERSION} already installed
fi

cd ${APP_PREFIX_DIR}
[[ -s current ]] && sudo unlink current
sudo ln --symbolic ${APP_DEST_DIR} current
echo current version set to ${VERSION}

cd ${BIN_DIR}
for bin in $(find ${APP_CURRENT}/ -maxdepth 1 -executable -type f -exec basename {} \;); do
    [[ -s $bin ]] || sudo ln --symbolic ${APP_CURRENT}/$bin
done

if [[ $TMP_DIR != "" ]]; then
    rm -rf ${TMP_DIR}
    echo removed up temp directory ${TMP_DIR}
fi