#!/usr/bin/env sh

set -e

if [ -z "${DEFAULT_MILL_VERSION}" ] ; then DEFAULT_MILL_VERSION="1.1.0-RC4-85-726bd3"; fi

if [ -z "${GITHUB_RELEASE_CDN}" ] ; then GITHUB_RELEASE_CDN=""; fi

if [ -z "$MILL_MAIN_CLI" ] ; then MILL_MAIN_CLI="${0}"; fi

MILL_REPO_URL="https://github.com/com-lihaoyi/mill"

MILL_BUILD_SCRIPT=""

if [ -f "build.mill" ] ; then
  MILL_BUILD_SCRIPT="build.mill"
elif [ -f "build.mill.scala" ] ; then
  MILL_BUILD_SCRIPT="build.mill.scala"
elif [ -f "build.sc" ] ; then
  MILL_BUILD_SCRIPT="build.sc"
fi

# `s/.*://`:
#   This is a greedy match that removes everything from the beginning of the line up to (and including) the last
#   colon (:). This effectively isolates the value part of the declaration.
#
#  `s/#.*//`:
#    This removes any comments at the end of the line.
#
#  `s/['\"]//g`:
#    This removes all single and double quotes from the string, wherever they appear (g is for "global").
#
#  `s/^[[:space:]]*//; s/[[:space:]]*$//`:
#    These two expressions trim any leading or trailing whitespace ([[:space:]] matches spaces and tabs).
TRIM_VALUE_SED="s/.*://; s/#.*//; s/['\"]//g; s/^[[:space:]]*//; s/[[:space:]]*$//"

if [ -z "${MILL_VERSION}" ] ; then
  if [ -f ".mill-version" ] ; then
    MILL_VERSION="$(tr '\r' '\n' < .mill-version | head -n 1 2> /dev/null)"
  elif [ -f ".config/mill-version" ] ; then
    MILL_VERSION="$(tr '\r' '\n' < .config/mill-version | head -n 1 2> /dev/null)"
  elif [ -f "build.mill.yaml" ] ; then
    MILL_VERSION="$(grep -E "mill-version:" "build.mill.yaml" | sed -E "$TRIM_VALUE_SED")"
  elif [ -n "${MILL_BUILD_SCRIPT}" ] ; then
    MILL_VERSION="$(grep -E "//\|.*mill-version" "${MILL_BUILD_SCRIPT}" | sed -E "$TRIM_VALUE_SED")"
  fi
fi

if [ -z "${MILL_VERSION}" ] ; then MILL_VERSION="${DEFAULT_MILL_VERSION}"; fi

MILL_USER_CACHE_DIR="${XDG_CACHE_HOME:-${HOME}/.cache}/mill"

if [ -z "${MILL_FINAL_DOWNLOAD_FOLDER}" ] ; then MILL_FINAL_DOWNLOAD_FOLDER="${MILL_USER_CACHE_DIR}/download"; fi

MILL_NATIVE_SUFFIX="-native"
MILL_JVM_SUFFIX="-jvm"
FULL_MILL_VERSION=$MILL_VERSION
ARTIFACT_SUFFIX=""

# Check if GLIBC version is at least the required version
# Returns 0 (true) if GLIBC >= required version, 1 (false) otherwise
check_glibc_version() {
  required_version="2.39"
  required_major=$(echo "$required_version" | cut -d. -f1)
  required_minor=$(echo "$required_version" | cut -d. -f2)
  # Get GLIBC version from ldd --version (first line contains version like "ldd (GNU libc) 2.31")
  glibc_version=$(ldd --version 2>/dev/null | head -n 1 | grep -oE '[0-9]+\.[0-9]+$' || echo "")
  if [ -z "$glibc_version" ]; then
    # If we can't determine GLIBC version, assume it's too old
    return 1
  fi
  glibc_major=$(echo "$glibc_version" | cut -d. -f1)
  glibc_minor=$(echo "$glibc_version" | cut -d. -f2)
  if [ "$glibc_major" -gt "$required_major" ]; then
    return 0
  elif [ "$glibc_major" -eq "$required_major" ] && [ "$glibc_minor" -ge "$required_minor" ]; then
    return 0
  else
    return 1
  fi
}

set_artifact_suffix(){
  if [ "$(expr substr $(uname -s) 1 5 2>/dev/null)" = "Linux" ]; then
    # Native binaries require new enough GLIBC; fall back to JVM launcher if older
    if ! check_glibc_version; then
      return
    fi
    if [ "$(uname -m)" = "aarch64" ]; then ARTIFACT_SUFFIX="-native-linux-aarch64"
    else ARTIFACT_SUFFIX="-native-linux-amd64"; fi
  elif [ "$(uname)" = "Darwin" ]; then
    if [ "$(uname -m)" = "arm64" ]; then ARTIFACT_SUFFIX="-native-mac-aarch64"
    else ARTIFACT_SUFFIX="-native-mac-amd64"; fi
  else
     echo "This native mill launcher supports only Linux and macOS." 1>&2
     exit 1
  fi
}

case "$MILL_VERSION" in
    *"$MILL_NATIVE_SUFFIX")
  MILL_VERSION=${MILL_VERSION%"$MILL_NATIVE_SUFFIX"}
  set_artifact_suffix
  ;;

    *"$MILL_JVM_SUFFIX")
    MILL_VERSION=${MILL_VERSION%"$MILL_JVM_SUFFIX"}
  ;;

    *)
  case "$MILL_VERSION" in
    0.1.*) ;;
    0.2.*) ;;
    0.3.*) ;;
    0.4.*) ;;
    0.5.*) ;;
    0.6.*) ;;
    0.7.*) ;;
    0.8.*) ;;
    0.9.*) ;;
    0.10.*) ;;
    0.11.*) ;;
    0.12.*) ;;
    *)
      set_artifact_suffix
  esac
  ;;
esac

MILL="${MILL_FINAL_DOWNLOAD_FOLDER}/$MILL_VERSION$ARTIFACT_SUFFIX"

# If not already downloaded, download it
if [ ! -s "${MILL}" ] || [ "$MILL_TEST_DRY_RUN_LAUNCHER_SCRIPT" = "1" ] ; then
  case $MILL_VERSION in
    0.0.* | 0.1.* | 0.2.* | 0.3.* | 0.4.* )
      MILL_DOWNLOAD_SUFFIX=""
      MILL_DOWNLOAD_FROM_MAVEN=0
      ;;
    0.5.* | 0.6.* | 0.7.* | 0.8.* | 0.9.* | 0.10.* | 0.11.0-M* )
      MILL_DOWNLOAD_SUFFIX="-assembly"
      MILL_DOWNLOAD_FROM_MAVEN=0
      ;;
    *)
      MILL_DOWNLOAD_SUFFIX="-assembly"
      MILL_DOWNLOAD_FROM_MAVEN=1
      ;;
  esac
  case $MILL_VERSION in
    0.12.0 | 0.12.1 | 0.12.2 | 0.12.3 | 0.12.4 | 0.12.5 | 0.12.6 | 0.12.7 | 0.12.8 | 0.12.9 | 0.12.10 | 0.12.11 )
      MILL_DOWNLOAD_EXT="jar"
      ;;
    0.12.* )
      MILL_DOWNLOAD_EXT="exe"
      ;;
    0.* )
      MILL_DOWNLOAD_EXT="jar"
      ;;
    *)
      MILL_DOWNLOAD_EXT="exe"
      ;;
  esac

  MILL_TEMP_DOWNLOAD_FILE="${MILL_OUTPUT_DIR:-out}/mill-temp-download"
  mkdir -p "$(dirname "${MILL_TEMP_DOWNLOAD_FILE}")"

  if [ "$MILL_DOWNLOAD_FROM_MAVEN" = "1" ] ; then
    MILL_DOWNLOAD_URL="https://repo1.maven.org/maven2/com/lihaoyi/mill-dist${ARTIFACT_SUFFIX}/${MILL_VERSION}/mill-dist${ARTIFACT_SUFFIX}-${MILL_VERSION}.${MILL_DOWNLOAD_EXT}"
  else
    MILL_VERSION_TAG=$(echo "$MILL_VERSION" | sed -E 's/([^-]+)(-M[0-9]+)?(-.*)?/\1\2/')
    MILL_DOWNLOAD_URL="${GITHUB_RELEASE_CDN}${MILL_REPO_URL}/releases/download/${MILL_VERSION_TAG}/${MILL_VERSION}${MILL_DOWNLOAD_SUFFIX}"
    unset MILL_VERSION_TAG
  fi


  if [ "$MILL_TEST_DRY_RUN_LAUNCHER_SCRIPT" = "1" ] ; then
    echo $MILL_DOWNLOAD_URL
    echo $MILL
    exit 0
  fi

  echo "Downloading mill ${MILL_VERSION} from ${MILL_DOWNLOAD_URL} ..." 1>&2
  curl -f -L -o "${MILL_TEMP_DOWNLOAD_FILE}" "${MILL_DOWNLOAD_URL}"

  chmod +x "${MILL_TEMP_DOWNLOAD_FILE}"

  mkdir -p "${MILL_FINAL_DOWNLOAD_FOLDER}"
  mv "${MILL_TEMP_DOWNLOAD_FILE}" "${MILL}"

  unset MILL_TEMP_DOWNLOAD_FILE
  unset MILL_DOWNLOAD_SUFFIX
fi

MILL_FIRST_ARG=""
if [ "$1" = "--bsp" ] || [ "${1#"-i"}" != "$1" ] || [ "$1" = "--interactive" ] || [ "$1" = "--no-server" ] || [ "$1" = "--no-daemon" ] || [ "$1" = "--help" ] ; then
  # Need to preserve the first position of those listed options
  MILL_FIRST_ARG=$1
  shift
fi

unset MILL_FINAL_DOWNLOAD_FOLDER
unset MILL_OLD_DOWNLOAD_PATH
unset OLD_MILL
unset MILL_VERSION
unset MILL_REPO_URL

# -D mill.main.cli is for compatibility with Mill 0.10.9 - 0.13.0-M2
# We don't quote MILL_FIRST_ARG on purpose, so we can expand the empty value without quotes
# shellcheck disable=SC2086
exec "${MILL}" $MILL_FIRST_ARG -D "mill.main.cli=${MILL_MAIN_CLI}" "$@"
