amper

#!/bin/sh

#
# Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
#

# Possible environment variables:
#   AMPER_DOWNLOAD_ROOT        Maven repository to download Amper dist from.
#                              default: https://packages.jetbrains.team/maven/p/amper/amper
#   AMPER_JRE_DOWNLOAD_ROOT    Url prefix to download Amper JRE from.
#                              default: https:/
#   AMPER_BOOTSTRAP_CACHE_DIR  Cache directory to store extracted JRE and Amper distribution
#   AMPER_JAVA_HOME            JRE to run Amper itself (optional, does not affect compilation)
#   AMPER_JAVA_OPTIONS         JVM options to pass to the JVM running Amper (does not affect the user's application)
#   AMPER_NO_WELCOME_BANNER    Disables the first-run welcome message if set to a non-empty value

set -e -u

# The version of the Amper distribution to provision and use
amper_version=0.9.2
# Establish chain of trust from here by specifying exact checksum of Amper distribution to be run
amper_sha256=33304bb301d0c5276ad4aa718ce8a10486fda4be45179779497d2036666bb16f

AMPER_DOWNLOAD_ROOT="${AMPER_DOWNLOAD_ROOT:-https://packages.jetbrains.team/maven/p/amper/amper}"
AMPER_JRE_DOWNLOAD_ROOT="${AMPER_JRE_DOWNLOAD_ROOT:-https:/}"

die() {
  echo >&2
  echo "$@" >&2
  echo >&2
  exit 1
}

download_and_extract() {
  moniker="$1"
  file_url="$2"
  file_sha="$3"
  sha_size="$4"
  cache_dir="$5"
  extract_dir="$6"
  show_banner_on_cache_miss="$7"

  if [ -e "$extract_dir/.flag" ] && [ "$(cat "$extract_dir/.flag")" = "${file_sha}" ]; then
    # Everything is up-to-date in $extract_dir, do nothing
    return 0;
  fi

  mkdir -p "$cache_dir"

  # Take a lock for the download of this file
  short_sha=$(echo "$file_sha" | cut -c1-32) # cannot use the ${short_sha:0:32} syntax in regular /bin/sh
  download_lock_file="$cache_dir/download-${short_sha}.lock"
  process_lock_file="$cache_dir/download-${short_sha}.$$.lock"
  echo $$ >"$process_lock_file"
  while ! ln "$process_lock_file" "$download_lock_file" 2>/dev/null; do
    lock_owner=$(cat "$download_lock_file" 2>/dev/null || true)
    if [ -n "$lock_owner" ] && ps -p "$lock_owner" >/dev/null; then
      echo "Another Amper instance (pid $lock_owner) is downloading $moniker. Awaiting the result..."
      sleep 1
    elif [ -n "$lock_owner" ] && [ "$(cat "$download_lock_file" 2>/dev/null)" = "$lock_owner" ]; then
      rm -f "$download_lock_file"
      # We don't want to simply loop again here, because multiple concurrent processes may face this at the same time,
      # which means the 'rm' command above from another script could delete our new valid lock file. Instead, we just
      # ask the user to try again. This doesn't 100% eliminate the race, but the probability of issues is drastically
      # reduced because it would involve 4 processes with perfect timing. We can revisit this later.
      die "Another Amper instance (pid $lock_owner) locked the download of $moniker, but is no longer running. The lock file is now removed, please try again."
    fi
  done

  # shellcheck disable=SC2064
  trap "rm -f \"$download_lock_file\"" EXIT
  rm -f "$process_lock_file"

  unlock_and_cleanup() {
    rm -f "$download_lock_file"
    trap - EXIT
    return 0
  }

  if [ -e "$extract_dir/.flag" ] && [ "$(cat "$extract_dir/.flag")" = "${file_sha}" ]; then
    # Everything is up-to-date in $extract_dir, just release the lock
    unlock_and_cleanup
    return 0;
  fi

  if [ "$show_banner_on_cache_miss" = "true" ] && [ -z "${AMPER_NO_WELCOME_BANNER:-}" ]; then
      echo
      echo '        _____  Welcome to                                  '
      echo '       /:::::|  ____   ___     ____      ____    __  ___   '
      echo '      /::/|::| |::::\_|:::\   |:::::\   /::::\  |::|/:::|  '
      echo '     /::/ |::| |::|\:::|\::\  |::|\::\ /:/__\:\ |:::/      '
      echo '    /::/__|::| |::| |::| |::| |::| |::|:::::::/ |::|       '
      echo '   /:::::::::| |::| |::| |::| |::|/::/ \::\__   |::|       '
      echo '  /::/    |::| |::| |::| |::| |:::::/   \::::|  |::|       '
      echo '                              |::|                         '
      echo "                              |::|  v.$amper_version       "
      echo
      echo "This is the first run of this version, so we need to download the actual Amper distribution."
      echo "Please give us a few seconds, subsequent runs will be faster."
      echo
  fi

  echo "Downloading $moniker..."

  temp_file="$cache_dir/download-file-$$.bin"
  rm -f "$temp_file"
  if command -v curl >/dev/null 2>&1; then
    if [ -t 1 ]; then CURL_PROGRESS="--progress-bar"; else CURL_PROGRESS="--silent --show-error"; fi
    # shellcheck disable=SC2086
    curl $CURL_PROGRESS -L --fail --retry 5 --connect-timeout 30 --output "${temp_file}" "$file_url"
  elif command -v wget >/dev/null 2>&1; then
    if [ -t 1 ]; then WGET_PROGRESS=""; else WGET_PROGRESS="-nv"; fi
    wget $WGET_PROGRESS --tries=5 --connect-timeout=30 --read-timeout=120 -O "${temp_file}" "$file_url"
  else
    die "ERROR: Please install 'wget' or 'curl', as Amper needs one of them to download $moniker"
  fi

  check_sha "$file_url" "$temp_file" "$file_sha" "$sha_size"

  rm -rf "$extract_dir"
  mkdir -p "$extract_dir"

  case "$file_url" in
    *".zip")
      if command -v unzip >/dev/null 2>&1; then
        unzip -q "$temp_file" -d "$extract_dir"
      else
        die "ERROR: Please install 'unzip', as Amper needs it to extract $moniker"
      fi ;;
    *)
      if command -v tar >/dev/null 2>&1; then
        tar -x -f "$temp_file" -C "$extract_dir"
      else
        die "ERROR: Please install 'tar', as Amper needs it to extract $moniker"
      fi ;;
  esac

  rm -f "$temp_file"

  echo "$file_sha" >"$extract_dir/.flag"

  # Unlock and cleanup the lock file
  unlock_and_cleanup

  echo "Download complete."
  echo
}

# usage: check_sha SOURCE_MONIKER FILE SHA_CHECKSUM SHA_SIZE
# $1 SOURCE_MONIKER (e.g. url)
# $2 FILE
# $3 SHA hex string
# $4 SHA size in bits (256, 512, ...)
check_sha() {
  sha_size=$4
  if command -v shasum >/dev/null 2>&1; then
    echo "$3 *$2" | shasum -a "$sha_size" --status -c || {
      die "ERROR: Checksum mismatch for $2 (downloaded from $1): expected checksum $3 but got $(shasum --binary -a "$sha_size" "$2" | awk '{print $1}')"
    }
    return 0
  fi

  shaNsumCommand="sha${sha_size}sum"
  if command -v "$shaNsumCommand" >/dev/null 2>&1; then
    echo "$3 *$2" | $shaNsumCommand -w -c || {
      die "ERROR: Checksum mismatch for $2 (downloaded from $1): expected checksum $3 but got $($shaNsumCommand "$2" | awk '{print $1}')"
    }
    return 0
  fi

  echo "Both 'shasum' and 'sha${sha_size}sum' utilities are missing. Please install one of them"
  return 1
}

# ********** System detection **********

kernelName=$(uname -s)
arch=$(uname -m)
case "$kernelName" in
  Darwin* )
    simpleOs="macos"
    jre_os="macosx"
    jre_archive_type="tar.gz"
    default_amper_cache_dir="$HOME/Library/Caches/JetBrains/Amper"
    ;;
  Linux* )
    simpleOs="linux"
    jre_os="linux"
    jre_archive_type="tar.gz"
    default_amper_cache_dir="$HOME/.cache/JetBrains/Amper"
    # If linux runs in 32-bit mode, we want the "fake" 32-bit architecture, not the real hardware,
    # because in this mode linux cannot run 64-bit binaries.
    # shellcheck disable=SC2046
    arch=$(linux$(getconf LONG_BIT) uname -m)
    ;;
  CYGWIN* | MSYS* | MINGW* )
    simpleOs="windows"
    jre_os="win"
    jre_archive_type=zip
    if command -v cygpath >/dev/null 2>&1; then
      default_amper_cache_dir=$(cygpath -u "$LOCALAPPDATA\JetBrains\Amper")
    else
      die "The 'cypath' command is not available, but Amper needs it. Use amper.bat instead, or try a Cygwin or MSYS environment."
    fi
    ;;
  *)
    die "Unsupported platform $kernelName"
    ;;
esac

amper_cache_dir="${AMPER_BOOTSTRAP_CACHE_DIR:-$default_amper_cache_dir}"

# ********** Provision Amper distribution **********

amper_url="$AMPER_DOWNLOAD_ROOT/org/jetbrains/amper/amper-cli/$amper_version/amper-cli-$amper_version-dist.tgz"
amper_target_dir="$amper_cache_dir/amper-cli-$amper_version"
download_and_extract "Amper distribution v$amper_version" "$amper_url" "$amper_sha256" 256 "$amper_cache_dir" "$amper_target_dir" "true"

# ********** Provision JRE for Amper **********

if [ "x${AMPER_JAVA_HOME:-}" = "x" ]; then
  case $arch in
    x86_64 | x64)    jre_arch="x64" ;;
    aarch64 | arm64) jre_arch="aarch64" ;;
    *) die "Unsupported architecture $arch" ;;
  esac

  # Auto-updated from syncVersions.main.kts, do not modify directly here
  zulu_version=25.28.85
  java_version=25.0.0

  pkg_type=jre
  platform="$jre_os $jre_arch"
  case $platform in
    "macosx x64")     jre_sha256=a73455c80413daa31af6b09589e3655bb8b8b91e4aa884ca7c91dc5552b9e974 ;;
    "macosx aarch64") jre_sha256=37316ebea9709eb4f8bc58f0ddd2f58e53720d3e7df6f78c64125915b44d322d ;;
    "linux x64")      jre_sha256=807e96e43db00af3390a591ed40f2c8c35f7f475fb14b6061dfb19db33702cba ;;
    "linux aarch64")  jre_sha256=ad75e426e3f101cfa018f65fde07d82b10337d4f85250ca988474d59891c5f50 ;;
    "win x64")        jre_sha256=d3c5db7864e6412ce3971c0b065def64942d7b0f3d02581f7f0472cac21fbba9 ;;
    "win aarch64")    jre_sha256=f5f6d8a913695649e8e2607fe0dc79c81953b2583013ac1fb977c63cb4935bfb; pkg_type=jdk ;;
    *) die "Unsupported platform $platform" ;;
  esac

  # URL for the JRE (see https://api.azul.com/metadata/v1/zulu/packages?release_status=ga&include_fields=java_package_features,os,arch,hw_bitness,abi,java_package_type,sha256_hash,size,archive_type,lib_c_type&java_version=25&os=macos,linux,win)
  # https://cdn.azul.com/zulu/bin/zulu25.28.85-ca-jre25.0.0-macosx_aarch64.tar.gz
  # https://cdn.azul.com/zulu/bin/zulu25.28.85-ca-jre25.0.0-linux_x64.tar.gz
  jre_url="$AMPER_JRE_DOWNLOAD_ROOT/cdn.azul.com/zulu/bin/zulu$zulu_version-ca-$pkg_type$java_version-${jre_os}_$jre_arch.$jre_archive_type"
  jre_target_dir="$amper_cache_dir/zulu$zulu_version-ca-$pkg_type$java_version-${jre_os}_$jre_arch"

  download_and_extract "Amper runtime v$zulu_version" "$jre_url" "$jre_sha256" 256 "$amper_cache_dir" "$jre_target_dir" "false"

  effective_amper_java_home=
  for d in "$jre_target_dir" "$jre_target_dir"/* "$jre_target_dir"/Contents/Home "$jre_target_dir"/*/Contents/Home; do
    if [ -e "$d/bin/java" ]; then
      effective_amper_java_home="$d"
    fi
  done

  if [ "x${effective_amper_java_home:-}" = "x" ]; then
    die "Unable to find bin/java under $jre_target_dir"
  fi
else
  effective_amper_java_home="$AMPER_JAVA_HOME"
fi

java_exe="$effective_amper_java_home/bin/java"
if [ '!' -x "$java_exe" ]; then
  die "Unable to find bin/java executable at $java_exe"
fi

# ********** Script path detection **********

# We might need to resolve symbolic links here
wrapper_path=$(realpath "$0")

# ********** Launch Amper **********

# In this section we construct the command line by prepending arguments from biggest to lowest precedence:
#   1. basic main class, CLI arguments, and classpath
#   2. user JVM args (AMPER_JAVA_OPTIONS)
#   3. default JVM args (prepended last, which means they appear first, so they are overridden by user args)

# 1. Prepend basic launch arguments
if [ "$simpleOs" = "windows" ]; then
  # Can't cygpath the '*' so it has to be outside
  classpath="$(cygpath -w "$amper_target_dir")\lib\*"
else
  classpath="$amper_target_dir/lib/*"
fi

set -- -cp "$classpath" org.jetbrains.amper.cli.MainKt "$@"

# 2. Prepend user JVM args from AMPER_JAVA_OPTS
#
# We use "xargs" to parse quoted JVM args from inside AMPER_JAVA_OPTS.
# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
#
# In Bash we could simply go:
#
#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
#   set -- "${ARGS[@]}" "$@"
#
# but POSIX shell has neither arrays nor command substitution, so instead we
# post-process each arg (as a line of input to sed) to backslash-escape any
# character that might be a shell metacharacter, then use eval to reverse
# that process (while maintaining the separation between arguments), and wrap
# the whole thing up as a single "set" statement.
#
# This will of course break if any of these variables contains a newline or
# an unmatched quote.
if [ -n "${AMPER_JAVA_OPTIONS:-}" ]; then
  eval "set -- $(
    printf '%s\n' "$AMPER_JAVA_OPTIONS" |
    xargs -n1 |
    sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
    tr '\n' ' '
  )" '"$@"'
fi

# 3. Prepend default JVM args
set -- \
    @"$amper_target_dir/amper.args" \
    "-Damper.wrapper.dist.sha256=$amper_sha256" \
    "-Damper.dist.path=$amper_target_dir" \
    "-Damper.wrapper.path=$wrapper_path" \
    "$@"

# Then we can launch with the overridden $@ arguments
exec "$java_exe" "$@"