#!/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}
# shellcheck disable=SC2044
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