#!/bin/sh

# The checksums below must correspond to the downloads for this version.

GO_VERSION=go1.16.3

case "$(uname -s):$(uname -m)" in

Linux:x86_64)

GO_PKG=${GO_VERSION}.linux-amd64.tar.gz

GO_PKG_SHA=951a3c7c6ce4e56ad883f97d9db74d3d6d80d5fec77455c6ada6c1f7ac4776d2

;;

Darwin:x86_64)

GO_PKG=${GO_VERSION}.darwin-amd64.tar.gz

GO_PKG_SHA=6bb1cf421f8abc2a9a4e39140b7397cdae6aca3e8d36dcff39a1a77f4f1170ac

;;

Darwin:arm64)

GO_PKG=${GO_VERSION}.darwin-arm64.tar.gz

GO_PKG_SHA=f4e96bbcd5d2d1942f5b55d9e4ab19564da4fad192012f6d7b0b9b055ba4208f

;;

*)

echo 1>&2 "I don't know how to install Go on your platform."

echo 1>&2 "Please install $GO_VERSION or later and add it to your PATH."

exit 1

;;

esac

archivesum() {

shasum -a256 "$ARCHIVE"

}

archiveok() {

test -f "$ARCHIVE" && archivesum | grep -q $GO_PKG_SHA

}

if go version 2>/dev/null | grep -q $GO_VERSION; then

go version

exit 0

fi

ROOTDIR="$( cd "$( dirname "$0" )/.." && pwd )"

VENDORDIR="$ROOTDIR/vendor"

DOWNLOAD_URL=https://storage.googleapis.com/golang/$GO_PKG

ARCHIVE="$VENDORDIR/$GO_PKG"

INSTALLDIR="$VENDORDIR/$GO_VERSION"

export GOROOT="$INSTALLDIR/go"

INSTALLEDGO="$GOROOT/bin/go"

if [ -x $INSTALLEDGO ]; then

"$INSTALLEDGO" version

exit 0

fi

if ! archiveok; then

echo "Downloading $DOWNLOAD_URL"

mkdir -p "$VENDORDIR"

if ! curl -L -o "$ARCHIVE" $DOWNLOAD_URL; then

rm -f "$ARCHIVE"

echo 1>&2 "download failed"

fi

if ! archiveok; then

archivesum 1>&2

echo 1>&2 "expected checksum $GO_PKG_SHA"

exit 1

fi

fi

rm -rf "$INSTALLDIR"

mkdir -p "$INSTALLDIR"

tar xf "$ARCHIVE" -C "$INSTALLDIR"

"$INSTALLEDGO" version