#!/bin/sh

set -e
OUT="$1"

find_node() {
    local NODE="${NODE_DIR}/bin/node"
    local CE_NODE="/opt/compiler-explorer/node/bin/node"
    local SYS_NODE="$(which node 2>/dev/null)"
    local SYS_NODEJS="$(which nodejs 2>/dev/null)"

    if test -x "${NODE}" -a -n "${NODE_DIR}"; then
        echo "${NODE}"
    elif test -x "${CE_NODE}"; then
        echo "${CE_NODE}"
    elif test -x "${SYS_NODE}"; then
        echo "${SYS_NODE}"
    elif test -x "${SYS_NODEJS}"; then
        echo "${SYS_NODEJS}"
    else
        >&2 echo "Unable to find a node"
    fi
}

NODE=$(find_node)

NODE_VERSION_USED=10
NODE_VERSION=$(${NODE} --version)
NODE_MAJOR_VERSION=$(echo ${NODE_VERSION} | cut -f1 -d. | sed 's/^v//g')

if test ${NODE_MAJOR_VERSION} -lt ${NODE_VERSION_USED}; then
    >&2 echo Compiler Explorer needs node v${NODE_VERSION_USED}.x, but ${NODE_VERSION} was found.
    >&2 echo Visit https://nodejs.org/ for installation instructions
    >&2 echo To configure where we look for node, set NODE_DIR to its installation base
    exit 1
fi

if test ${NODE_MAJOR_VERSION} -gt ${NODE_VERSION_USED}; then
    >&2 echo Compiler Explorer needs node v${NODE_VERSION_USED}.x, but ${NODE_VERSION} was found.
    >&2 echo The higher node version might work but it has not been tested.
fi

echo ${NODE} > ${OUT}