#!/usr/bin/env bash

NVM_VERSION="1.9.0"
NVM_VERSION_V="v${NVM_VERSION}"

TAR_NEEDS_WILDCARDS_OPT="$(tar --help | grep "\--wildcards")"

if [ -n "$TAR_NEEDS_WILDCARDS_OPT" ]; then
  TAR_WILDCARDS_OPT="--wildcards"
else
  TAR_WILDCARDS_OPT=""
fi

if [ -n "$NVM_TEST" ]; then
  NVM_TGZ_URL="https://github.com/jchip/nvm/archive/${NVM_VERSION_V}.tar.gz"
else
  NVM_TGZ_URL="https://registry.npmjs.org/@jchip/nvm/-/nvm-${NVM_VERSION}.tgz"
fi

if [ -z "${NVM_HOME}" ]; then
  export NVM_HOME="$HOME/nvm"
fi

function fetch() {
  curl=$(which curl)
  if [ "$?" = "0" ]; then
    curl --fail -L $1 -o $2
    return $?
  fi

  wget=$(which wget)
  if [ "$?" = "0" ]; then
    wget "$1" --output-document="$2"
    return $?
  fi

  echo "No curl or wget found"
  exit 1
}

function tmpdir() {
  if [ -n "$TMPDIR" ]; then
    echo "$TMPDIR"
  else
    echo "/tmp"
  fi
}

VERSIONS_TAB_FILE_URL="https://nodejs.org/dist/index.tab"

function getLtsVersionByTabFile() {
  TAB_FILE="$(tmpdir)/nodejs.versions.tab"

  fetch $VERSIONS_TAB_FILE_URL $TAB_FILE
  local fv
  fv=$(cut -f1,10 "$TAB_FILE" | tail -n +2 | egrep -v $'\t-$' | head -1 | cut -f1 | egrep -o 'v[0-9]+\.[0-9]+\.[0-9]+$')

  if [ -n "$fv" ]; then
    echo "$fv"
  else
    echo "v20.12.0"
  fi
}

echo "Checking for latest node.js LTS from ${VERSIONS_TAB_FILE_URL}"
DEFAULT_NODE_VERSION=$(getLtsVersionByTabFile)
echo "Determined node.js LTS version to be $DEFAULT_NODE_VERSION"

function getOs() {
  uname -s | tr "[:upper:]" "[:lower:]"
}

function getArch() {
  case $(uname -m) in
    x86_64)
      echo "x64"
      ;;
    i686 | i386)
      echo "x86"
      ;;
    *)
      uname -m | tr "[:upper:]" "[:lower:]"
      ;;
  esac
}

function fetchNodeJS() {
  local version
  version="$1"

  local nodejsMirror
  if [ -n "${NVM_NODEJS_ORG_MIRROR}" ]; then
    nodejsMirror="${NVM_NODEJS_ORG_MIRROR}"
  else
    nodejsMirror="https://nodejs.org/dist"
  fi

  local tgzFile
  tgzFile="node-${version}-$(getOs)-$(getArch).tar.gz"
  nodejsBinUrl="${nodejsMirror}/${version}/${tgzFile}"

  local cacheDir
  cacheDir="${NVM_CACHE}/${version}"
  mkdir -p "${cacheDir}"
  local destTgzFile
  destTgzFile="${cacheDir}/node.tgz"

  if [ ! -f "${destTgzFile}" ]; then
    echo "Fetching ${nodejsBinUrl}"

    if ! fetch "${nodejsBinUrl}" "${destTgzFile}"; then
      rm -rf "${cacheDir}"
    fi
  fi

  if [ -f "${destTgzFile}" ]; then
    tar ${TAR_WILDCARDS_OPT} -xzf "${destTgzFile}" --strip=2 --directory "${NVM_HOME}" "*/bin/node"
  else
    echo "Unable to fetch ${nodejsBinUrl}"
    exit 1
  fi
}

NVM_CACHE="${NVM_HOME}/cache"
NVM_NODE="${NVM_HOME}/nodejs"
NVM_NODE_BIN="${NVM_HOME}/node"

function installNvm() {
  if [ ! -d "${NVM_CACHE}" ]; then
    mkdir -p "${NVM_CACHE}"
  fi

  local nvmDestTgzFile
  nvmDestTgzFile="${NVM_CACHE}/nvm-${NVM_VERSION_V}.tgz"

  echo "Fetching ${NVM_TGZ_URL}"
  fetch "${NVM_TGZ_URL}" "${nvmDestTgzFile}"

  local nvm_files
  nvm_files="$(tmpdir)/nvm_files.txt"
  cat >${nvm_files}<<EOF
*/bin
*/dist
*/package.json
EOF

  tar ${TAR_WILDCARDS_OPT} -xzf "${nvmDestTgzFile}" --directory="${NVM_HOME}" --strip=1 --files-from="$nvm_files"

  # Ensure nvx has execute permissions
  if [ -f "${NVM_HOME}/bin/nvx" ]; then
    chmod +x "${NVM_HOME}/bin/nvx"
  fi
}

fetchNodeJS "${DEFAULT_NODE_VERSION}"

if [ -f "test.sh" ]; then
  source test.sh
else
  installNvm
fi

source "${NVM_HOME}/bin/nvm.sh"

function setBashRc() {
  BASH_RC="${HOME}/.bashrc"
  BASH_PROFILE="${HOME}/.bash_profile"

  local rcfile

  if [ -f "${BASH_RC}" ]; then
    rcfile="${BASH_RC}"
  else
    rcfile="${BASH_PROFILE}"
  fi

  if [ ! -f "${rcfile}" ]; then
    touch "${rcfile}"
  fi

  ${NVM_NODE_BIN} ${NVM_HOME}/bin/install_bashrc.js "${rcfile}"
}

# http://zsh.sourceforge.net/Intro/intro_3.html
function setZshRc() {
  ZD=${HOME}
  if [ -n "${ZDOTDIR}" ]; then
    ZD=${ZDOTDIR}
  fi
  ZSH_RC="${ZD}/.zshrc"
  ZSH_ENV="${ZD}/.zshenv"

  if [ ! -f "${ZSH_RC}" ]; then
    touch "${ZSH_RC}"
  fi

  if [ ! -f "${ZSH_ENV}" ]; then
    touch "${ZSH_ENV}"
  fi

  # Add to both .zshenv (for non-interactive shells) and .zshrc (for interactive shells)
  # The guard in the script prevents double initialization
  ${NVM_NODE_BIN} ${NVM_HOME}/bin/install_bashrc.js "${ZSH_ENV}" zsh
  ${NVM_NODE_BIN} ${NVM_HOME}/bin/install_bashrc.js "${ZSH_RC}" zsh
}

setBashRc
setZshRc

nvm install $DEFAULT_NODE_VERSION

# Run nvx --install-to-user to set up LaunchAgent on macOS
if [ -f "${NVM_HOME}/bin/nvx" ]; then
  "${NVM_HOME}/bin/nvx" --install-to-user 2>/dev/null || true
fi