configure

#!/usr/bin/env sh

NOT_CRAN=${NOT_CRAN:-"false"}
LIBR_POLARS_BUILD=${LIBR_POLARS_BUILD:-""}

# Detect if this is on R-universe.
MY_UNIVERSE=${MY_UNIVERSE:-""}

LIBNAME="libr_polars.a"
LIBR_POLARS_DEFAULT_PATH="$(pwd)/tools/${LIBNAME}"
LIBR_POLARS_PATH=${LIBR_POLARS_PATH:-${LIBR_POLARS_DEFAULT_PATH}}

# not used on macOS
ADDITIONAL_PKG_LIBS_FLAG="-lrt"

export PATH="$PATH:$HOME/.cargo/bin"

check_cargo() {
  if [ ! "$(command -v cargo)" ]; then
    echo ""
    echo "------------------------- [RUST NOT FOUND] -------------------------"
    echo "The 'cargo' command was not found on the PATH. Please install rustc"
    echo "from: https://www.rust-lang.org/tools/install"
    echo ""
    echo "Alternatively, you may install cargo from your OS package manager:"
    echo " - Debian/Ubuntu: apt-get install cargo"
    echo " - Fedora/CentOS: dnf install cargo"
    echo " - macOS: brew install rustc"
    echo "--------------------------------------------------------------------"
    echo ""
    exit 1
  else
    echo ""
    echo "--------------------------- [RUST FOUND] ---------------------------"
    cargo -V
    echo ""
    rustc -vV
    echo "--------------------------------------------------------------------"
    echo ""
  fi
}

check_bin_lib() {
  if [ "${NOT_CRAN}" = "true" ] && [ -z "${LIBR_POLARS_BUILD}" ]; then
    LIBR_POLARS_BUILD="false"
  fi

  # On R-universe, we try to download the pre-built binary from GitHub releases.
  if [ -n "${MY_UNIVERSE}" ] && [ -z "${LIBR_POLARS_BUILD}" ]; then
    echo ""
    echo "--------------------- [SETTING FOR R-UNIVERSE] ---------------------"
    echo "It seems that this is on R-universe <${MY_UNIVERSE}>."
    echo "Trying to download pre-built binary."
    echo "--------------------------------------------------------------------"
    echo ""
    LIBR_POLARS_BUILD="false"
  fi

  if [ "${LIBR_POLARS_BUILD}" = "false" ] && [ -f "tools/lib-sums.tsv" ] && [ ! -f "${LIBR_POLARS_PATH}" ]; then
    echo ""
    echo "---------------- [TRY TO DOWNLOAD PRE-BUILT BINARY] ----------------"
    "${R_HOME}/bin${R_ARCH_BIN}/Rscript" "tools/prep-lib.R" || echo "Failed to download pre-built binary."
    echo "--------------------------------------------------------------------"
    echo ""
  fi

  if [ "${LIBR_POLARS_BUILD}" = "false" ] && [ -f "${LIBR_POLARS_PATH}" ]; then
    echo ""
    echo "---------------------- [LIBRARY BINARY FOUND] ----------------------"
    echo "The library was found at <${LIBR_POLARS_PATH}>. No need to build it."
    echo ""
    echo "Note: rustc version: $(command -v rustc >/dev/null && rustc -V || echo 'Not found')"
    echo "--------------------------------------------------------------------"
    echo ""
    sed -e "s|@RUST_TARGET@||" -e "s|@ADDITIONAL_PKG_LIBS_FLAG@|${ADDITIONAL_PKG_LIBS_FLAG}|" src/Makevars.in >src/Makevars
    if [ "${LIBR_POLARS_PATH}" != "${LIBR_POLARS_DEFAULT_PATH}" ]; then
      echo ""
      echo "------------------------ [COPYING BINARY] ------------------------"
      echo "Copying <${LIBR_POLARS_PATH}> to <${LIBR_POLARS_DEFAULT_PATH}>."
      mkdir -p "$(dirname "${LIBR_POLARS_DEFAULT_PATH}")"
      cp "${LIBR_POLARS_PATH}" "${LIBR_POLARS_DEFAULT_PATH}" || echo "Failed to copy binary."
      echo "------------------------------------------------------------------"
      echo ""
    fi
    exit 0
  elif [ "${LIBR_POLARS_BUILD}" = "false" ] && [ -f "${LIBR_POLARS_DEFAULT_PATH}" ]; then
    echo ""
    echo "---------------------- [LIBRARY BINARY FOUND] ----------------------"
    echo "The library was not found at <${LIBR_POLARS_PATH}>,"
    echo "but was found at <${LIBR_POLARS_DEFAULT_PATH}>."
    echo "No need to build it."
    echo ""
    echo "Note: rustc version: $(command -v rustc >/dev/null && rustc -V || echo 'Not found')"
    echo "--------------------------------------------------------------------"
    echo ""
    sed -e "s|@RUST_TARGET@||" -e "s|@ADDITIONAL_PKG_LIBS_FLAG@|${ADDITIONAL_PKG_LIBS_FLAG}|" src/Makevars.in >src/Makevars
    exit 0
  elif [ "${LIBR_POLARS_BUILD}" = "false" ]; then
    echo ""
    echo "-------------------- [LIBRARY BINARY NOT FOUND] --------------------"
    echo "The library was not found at <${LIBR_POLARS_PATH}>."
    echo "Falling back to building from source."
    echo "--------------------------------------------------------------------"
    echo ""
  fi
}

check_darwin() {
  if [ "$(uname)" = "Darwin" ]; then
    ADDITIONAL_PKG_LIBS_FLAG=""
  fi
}

detect_target_option() {
  for option in "$@"; do
    case "${option}" in
    --host=*)
      specified_target="$(echo "${option}" | sed -e 's/--host=//' | sed -E 's/([0-9]+\.)*[0-9]+$//')"
      echo ""
      echo "------------------------------ [DETECTED TARGET] ------------------------------"
      echo "The target was specified as <${specified_target}> via the '--host' option."
      echo "-------------------------------------------------------------------------------"
      echo ""
      export TARGET="${specified_target}"
      ;;
    *) ;;
    esac
    shift
  done
}

detect_target_option "$@"
check_darwin
check_bin_lib
check_cargo

RUST_TARGET="${TARGET:-$(rustc -vV | grep host | cut -d' ' -f2)}"

sed \
  -e "s|@RUST_TARGET@|${RUST_TARGET}|" \
  -e "s|@ADDITIONAL_PKG_LIBS_FLAG@|${ADDITIONAL_PKG_LIBS_FLAG}|" \
  src/Makevars.in >src/Makevars

exit 0