ISTIO_ENVOY_LINUX_RELEASE_NAME="${ISTIO_ENVOY_LINUX_RELEASE_NAME:-${SIDECAR}-${ISTIO_ENVOY_VERSION}}"
ISTIO_ENVOY_LINUX_RELEASE_PATH="${ISTIO_ENVOY_LINUX_RELEASE_PATH:-${ISTIO_ENVOY_LINUX_RELEASE_DIR}/${ISTIO_ENVOY_LINUX_RELEASE_NAME}}"

# There is no longer an Istio built Envoy binary available for the Mac. Copy the Linux binary as the Mac binary was
# very old and likely no one was really using it (at least temporarily).

ISTIO_ZTUNNEL_VERSION="${ISTIO_ZTUNNEL_VERSION:-${ZTUNNEL_REPO_SHA}}"
ISTIO_ZTUNNEL_RELEASE_URL="${ISTIO_ZTUNNEL_RELEASE_URL:-${ISTIO_ZTUNNEL_BASE_URL}/ztunnel-${ISTIO_ZTUNNEL_VERSION}-${TARGET_ARCH}}"
ISTIO_ZTUNNEL_LINUX_RELEASE_NAME="${ISTIO_ZTUNNEL_LINUX_RELEASE_NAME:-ztunnel-${ISTIO_ZTUNNEL_VERSION}}"
ISTIO_ZTUNNEL_LINUX_RELEASE_DIR="${ISTIO_ZTUNNEL_LINUX_RELEASE_DIR:-${TARGET_OUT_LINUX}/release}"

export GO111MODULE=on
go get -u "istio.io/api@${UPDATE_BRANCH}"
go get -u "istio.io/client-go@${UPDATE_BRANCH}"
go mod tidy

sed -i "s/^BUILDER_SHA=.*\$/BUILDER_SHA=$(getSha release-builder)/" prow/release-commit.sh
chmod +x prow/release-commit.sh

else
  SHA=$(grep "istio.io/api" go.mod | head -n1 | awk '{ print $2 }')
  if [[ ${SHA} == *"-"* && ! ${SHA} =~ -rc.[0-9]$ && ! ${SHA} =~ -beta.[0-9]$ && ! ${SHA} =~ -alpha.[0-9]$ ]]; then
    # not an official release or release candidate, so get the commit sha
    SHA=$(echo "${SHA}" | awk -F '-' '{ print $NF }')
  fi
fi

if [ -z "${SHA}" ]; then

ISTIO_ENVOY_RELEASE_URL=${ISTIO_ENVOY_RELEASE_URL:-${ISTIO_ENVOY_BASE_URL}/envoy-alpha-${ISTIO_ENVOY_LINUX_VERSION}.tar.gz}
ISTIO_ENVOY_ARM_RELEASE_URL=${ISTIO_ENVOY_ARM_RELEASE_URL:-${ISTIO_ENVOY_BASE_URL}/envoy-alpha-${ISTIO_ENVOY_LINUX_VERSION}-arm64.tar.gz}
SLEEP_TIME=60

printf "Verifying %s is available\n" "$ISTIO_ENVOY_RELEASE_URL"

GCFLAGS=${GCFLAGS:-}
export CGO_ENABLED=${CGO_ENABLED:-0}

if [[ "${STATIC}" !=  "1" ]];then
    LDFLAGS=""
fi

# gather buildinfo if not already provided
# For a release build BUILDINFO should be produced
# at the beginning of the build and used throughout
if [[ -z ${BUILDINFO} ]];then
    BUILDINFO=$(mktemp)
    "${SCRIPTPATH}/report_build_info.sh" > "${BUILDINFO}"
fi