npmw

#!/usr/bin/env sh

VERSION=${NODE_VERSION:-"v18.20.3"}
BIN_NAME="npm"

# Define API
# ==========

# https://github.com/client9/shlib/blob/master/uname_os.sh
detect_os() {
  os=$(uname -s | tr '[:upper:]' '[:lower:]')

  # fixed up for https://github.com/client9/shlib/issues/3
  case "$os" in
    msys*) os="win" ;;
    mingw*) os="win" ;;
    cygwin*) os="win" ;;
    win*) os="win" ;; # for windows busybox and like # https://frippery.org/busybox/
  esac

  # other fixups here
  echo "$os"
}

# https://github.com/client9/shlib/blob/master/uname_arch.sh
detect_arch() {
  arch=$(uname -m)
  case $arch in
    x86_64) arch="x64" ;;
    x86) arch="x86" ;;
    i686) arch="x86" ;;
    i386) arch="x86" ;;
    aarch64) arch="arm64" ;;
    armv5*) arch="armv5" ;;
    armv6*) arch="armv6" ;;
    armv7*) arch="armv7" ;;
  esac
  echo ${arch}
}

# https://github.com/client9/shlib/blob/master/http_download.sh
download_file() {
  local_file=$1
  source_url=$2
  header=$3
  if [ -z "$header" ]; then
    code=$(curl -w '%{http_code}' -sL -o "$local_file" "$source_url")
  else
    code=$(curl -w '%{http_code}' -sL -H "$header" -o "$local_file" "$source_url")
  fi
  if [ "$code" != "200" ]; then
    echo "Error! Downloading file from URL '$source_url' received HTTP status '$code'"
    return 1
  fi
  return 0
}

download_file_once () {
  URL=$1
  FILE=$2

  if [ ! -f "${FILE}" ]; then
      mkdir -p "$(dirname "$FILE")"
      FILE_TMP="$2.tmp"
      download_file "$FILE_TMP" "$URL"
      mv "$FILE_TMP" "$FILE"
  fi
}

unarchive_file() {
  FILE=$1
  DIR=$2

  mkdir -p "$DIR"
  if [ "${FILE##*.}" = "zip" ] ; then
    unzip -q "$FILE" -d "$DIR"
    mv "$DIR"/*/* "$DIR"
  else
    tar -xf "$FILE" -C "$DIR" --strip-components=1
  fi
}

# Download or use installed tool
# ==============================

OS=$(detect_os)
ARCH=$(detect_arch)
DOWNLOAD_DIR="node"

BIN_DOWNLOAD_NAME="node"
BIN_ARCHIVE_EXT="tar.gz"
BIN_PATH="bin/${BIN_NAME}"
if [ "$OS" = "win" ] ; then
  BIN_PATH="${BIN_NAME}"
  BIN_ARCHIVE_EXT="zip"
fi

BIN_DOWNLOAD_URL="https://nodejs.org/dist/${VERSION}/node-${VERSION}-${OS}-${ARCH}.${BIN_ARCHIVE_EXT}"

BIN_ROOT="${DOWNLOAD_DIR}"
BIN_ARCHIVE_FILE="${BIN_ROOT}/${BIN_DOWNLOAD_NAME}-${VERSION}.${BIN_ARCHIVE_EXT}"
BIN_ARCHIVE_DIR="${BIN_ROOT}/dist"
BIN_EXEC_FILE="${BIN_ARCHIVE_DIR}/${BIN_PATH}"
BIN_EXEC_DIR=$(dirname "$BIN_EXEC_FILE")

if [ ! -f "${BIN_EXEC_FILE}" ]; then
  mkdir -p "${BIN_ARCHIVE_DIR}"
  download_file_once "$BIN_DOWNLOAD_URL" "$BIN_ARCHIVE_FILE"
  unarchive_file "$BIN_ARCHIVE_FILE" "$BIN_ARCHIVE_DIR"
  chmod +x "${BIN_EXEC_FILE}"
fi

# Execute the binary
# ==================

export PATH=$(pwd)/$BIN_EXEC_DIR:$PATH
"./${BIN_EXEC_FILE}" "$@"