#!/bin/bash

set -xeou pipefail

INSTALL_GOLANG_VERSION=${1}
GOLANG_DOWNLOAD_SHA256=${2}

GOLANG_DOWNLOAD_URL="https://golang.org/dl/go${INSTALL_GOLANG_VERSION}.linux-${TARGETARCH:-amd64}.tar.gz"

function build_debian() {
    curl -fsSL "$GOLANG_DOWNLOAD_URL" -o golang.tar.gz
    echo "${GOLANG_DOWNLOAD_SHA256}  golang.tar.gz" | sha256sum -c -
    tar -C /usr/local -xzf golang.tar.gz
    rm golang.tar.gz
}

function build_ubi() {
    GO_MAJOR_VERSION=${INSTALL_GOLANG_VERSION%.*}
    GOLANG_FIPS_BRANCH="go${GO_MAJOR_VERSION}-openssl-fips"

    mkdir -p /tmp/golang
    curl -fsSL "$GOLANG_DOWNLOAD_URL" -o golang.tar.gz
    echo "${GOLANG_DOWNLOAD_SHA256}  golang.tar.gz" | sha256sum -c -
    tar -C /tmp/golang -xzf golang.tar.gz

    # For UBI, we will be installing golang-fips
    git clone https://github.com/golang-fips/go.git --branch ${GOLANG_FIPS_BRANCH} --single-branch --depth 1 /usr/local/go

    cd /usr/local/go/src

    PATH=$PATH:/tmp/golang/go/bin CGO_ENABLED=1 ./make.bash

    rm -rf /usr/local/go/pkg/*/cmd /usr/local/go/pkg/bootstrap \
           /usr/local/go/pkg/obj /usr/local/go/pkg/tool/*/api \
           /usr/local/go/pkg/tool/*/go_bootstrap /usr/local/go/src/cmd/dist/dist \
           /usr/local/go/.git* /tmp/golang

    ln -sf /usr/local/go/bin/go /usr/local/go/bin/gofmt /usr/local/go/bin/godoc /usr/local/bin/
}


BUILD_OS=${BUILD_OS:-debian}

if [[ $BUILD_OS =~ debian ]]; then
    build_debian "$@"
elif [[ $BUILD_OS =~ ubi ]]; then
    build_ubi "$@"
fi