jeka

#!/bin/bash
#
# Copyright 2014-2024  the original author or authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#       https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
#  limitations under the License.
#

#
# Script for launching JeKa tool.
#
# Authors: Jerome Angibaud, Patrick Santana
#
# Rules for selecting a JDK :
# - if JEKA_JDK_HOME env var is specified, select it
# - if a jeka.java.version property is specified
#     - if a jeka.jdk.[version] property is specified, select the specified path.
#     - else, look in cache or download the proper JDK
# - else
#   - if JAVA_HOME env var is specified, select it
#   - else, look in cache and download default version (temurin 21)
#
# Rules for reading a property (said "my.prop") :
# - if a command line argument contains "-Dmy.prop=xxx", returns 'xxx'
# - if an OS environment variable 'my.prop' exists, returns this value
# - if property is defined in $BASE_DIR/jeka.properties, returns this value
# - look recursively in $BASE_DIR/../jeka.properties. Stop at first folder ancestor not having a jeka.properties file
# - look in JEKA_USER_HOME/global.properties
#

set -e
#####################
# Global vars
#####################

declare CMD_LINE_ARGS=("$@")
declare -a INTERPOLATED_ARGS

declare JEKA_VERSION_PROP_NAME="jeka.java.version"
declare JEKA_JAR_NAME="dev.jeka.jeka-core.jar"

declare JEKA_USER_HOME
declare GLOBAL_PROP_FILE
declare BASE_DIR  # To find BASE_DIR/jeka/local.properties, BASE_DIR/jeka/def, ...
declare CURRENT_SCRIPT_DIR
declare -i PROGRAM_OPTION_INDEX
CURRENT_SCRIPT_DIR="$( cd "$(dirname "$0")" ; pwd -P )"

# Global variables are preferred over passing all arguments
# in method call, cause they are too many.
declare DEFAULT_JAVA_VERSION="21"
declare JDK_DOWNLOAD_DISTRIB="temurin"
declare JDK_DOWNLOAD_LIBC_TYPE="glibc"  # default for linux, overridden for other os
declare JDK_DOWNLOAD_FILE_TYPE="tar.gz" # overridden for *WIN os
declare JDK_DOWNLOAD_OS
declare JDK_DOWNLOAD_ARCH

declare IS_VERBOSE # we should not log anything when on the green path, except if '-lsu' arg is present
declare IS_QUIET # we should log only error msg

declare LOG_DEBUG # DEBUG
declare DRY_RUN  # Debugging purpose
declare DEFAULT_BASE_DIR="."


#######################################
# Prints passed arguments on the stderr
# Globals:
#   none
# Arguments:
#   $*
#######################################
msg() {
  echo "$*" 1>&2
}

#######################################
# Gets the sub-string part ending before '#' of a specified string. ('Hello#World' should returns 'Hello')
# Globals:
#   none
# Arguments:
#   $1 : the string to extract substring from
# Outputs:
#   Write extracted sub-string to stdout
#######################################
substring_before_hash() {
    # Extract the substring before '#' using cut
    result=$(echo "$1" | cut -d'#' -f1)

    # Echo the resulting substring
    echo "$result"
}

#######################################
# Gets the sub-string part starting after '#' of a specified string. ('Hello#World' should returns 'World')
# Globals:
#   none
# Arguments:
#   $1 : the string to extract substring from
# Outputs:
#   Write extracted sub-string to stdout
#######################################
substring_after_hash() {
    # Extract the substring after '#' using parameter expansion
    result=${1#*#}

    # If the input string did not have a '#', return empty. Otherwise, return the result
    if [ "$result" == "$1" ]; then
        echo ""
    else
        echo "$result"
    fi
}

array_contains() {
    local search=$1; shift
    local array=("$@")

    for element in "${array[@]}"; do
        if [[ $element == $search ]]; then
            echo "true"
            return 0 # Element found, return success
        fi
    done
    echo "false"
}


#######################################
# Gets the value of a property, declared as '-Dprop.name=prop.value' in an array.
# Globals:
#   CMD_LINE_ARGS (read)
# Arguments:
#   $1 : the property name
# Outputs:
#   Write property value to stdout
#######################################
get_system_prop_from_args() {
  local prop_name=$1
  local prefix="-D$prop_name="
  for arg in "${CMD_LINE_ARGS[@]}"
      do
        if [[ "$arg" == "$prefix"* ]] ; then
            echo "${arg#$prefix}"
        fi
      done
}

#######################################
# Download specified zip/tgz file and unpack it to the specified dir
# Globals:
#   none
# Arguments:
#   $1 : url to download file
#   $2 : the target directory path to unzip/unpack content
#   $3 : optional file type to unpack ('zip' or 'tar.gz'). Default is 'zip'.
#######################################
download_and_unpack() {
  local url=$1
  local dir=$2
  local file_type=$3  # 'zip' or 'tar.gz'
  local temp_file
  temp_file=$(mktemp)
  rm "$temp_file"

  ## download
  if [ -x "$(command -v curl)" ]; then
    local silent_flag="s"
    if [ "$IS_VERBOSE" != "" ]; then
      silent_flag=""
    fi
    curl -"$silent_flag"Lf --fail --show-error -o "$temp_file" "$url"
    if [ $? -ne 0 ]; then
        msg "Curl request failed $url"
        msg "Returned code: $?"
        exit 1
    fi
  elif [ -x "$(command -v wget)" ]; then
    wget -q -O "$temp_file" "$url"
  else
    msg "Error: curl or wget not found, please make sure one of them is installed"
    exit 1
  fi

  ## unpack
  mkdir -p "$dir"
  if [ "$file_type" == "tar.gz" ]; then
    gzip -cd "$temp_file" | tar xf - -C "$dir"
  else
    unzip -qq -o "$temp_file" -d "$dir"
  fi
  rm "$temp_file"
}

#######################################
# Computes if we should print something on console when downloading files
# Globals:
#   CMD_LINE_ARGS (read)
#   IS_VERBOSE (write)
# Arguments:
#   None
#######################################
compute_VERBOSE_QUIET() {
  for arg in "${CMD_LINE_ARGS[@]}"
    do
      if [ "$arg" == "--verbose" ] || [ "$arg" == "-v" ] || [ "$arg" == "-d" ] || [ "$arg" == "--debug" ]; then
          IS_VERBOSE="true"
      elif [ "$arg" == "--quiet" ] || [ "$arg" == "-q" ]; then
          IS_QUIET="true"
      fi
    done
}

#######################################
# Prints passed arguments on the standard stream, only if LOG_DEBUG is non-empty
# Globals:
#   LOG_DEBUG (read)
# Arguments:
#   $*
#######################################
debug() {
  if [ -n "$LOG_DEBUG" ] || [ -n "$IS_VERBOSE" ]; then
    echo "$*" 1>&2
  fi
}

#######################################
# Prints passed arguments on the standard stream, only if IS_QUIET is empty
# Globals:
#   IS_QUIET (read)
# Arguments:
#   $*
#######################################
info() {
  if [ -z "$IS_QUIET" ]; then
    echo "$*" 1>&2
  fi
}

#######################################
# Gets the Jeka directory for the user. This is where are located global.properties and cache dirs.
# Globals:
#   JEKA_USER_HOME (read)
# Arguments:
#   none
# Outputs:
#   Write location to stdout
#######################################
get_jeka_user_home() {
  if [ -z "$JEKA_USER_HOME" ]; then
    echo "$HOME/.jeka"
  else
    echo "$JEKA_USER_HOME"
  fi
}

#######################################
# Gets the effective cache dir for Jeka user
# Globals:
#   JEKA_CACHE_DIR (read)
#   JEKA_USER_HOME (read)
# Arguments:
#   none
# Outputs:
#   Write location to stdout
#######################################
get_cache_dir() {
  if [ -z "$JEKA_CACHE_DIR" ]; then
      echo "$JEKA_USER_HOME/cache"
    else
      echo "$JEKA_CACHE_DIR"
    fi
}

#######################################
# Gets the dir for caching projects cloned from git
# Globals:
#   JEKA_CACHE_DIR (read)
#   JEKA_USER_HOME (read)
# Arguments:
#   none
# Outputs:
#   Write location to stdout
#######################################
get_git_cache_dir() {
  echo "$(get_cache_dir)/git"
}



#######################################
# Gets the value of a property declared within a property file
# Globals:
#   none
# Arguments:
#   $1 : the path of the property file
#   $2 : the property name
# Outputs:
#   Write property value to stdout
#######################################
get_prop_value_from_file() {
    local file=$1
    local key=$2
    if [ ! -f "$file" ]; then
        return
    fi
    local value
    value=$(grep "^${key}=" "${file}")
    local -i key_length
    key_length=${#key}
    ((key_length++))
    echo "${value:key_length}"
}

#######################################
# Gets the translation of a property name (as my.prop) to an env var name (as MY_PROP)
# Globals:
#   none
# Arguments:
#   $1 : the property name
# Outputs:
#   Write env var name to stdout
#######################################
get_env_var_name() {
  local prop_name="$1"
  local result=${prop_name^}
  result=${result//./_}
  result=${result//-/_}
  echo "$result"
}

#######################################
# Resolves and returns the value of a property by looking in command line args, env var and jeka.properties files
# Globals:
#   CMD_LINE_ARGS (read)
# Arguments:
#   $1 : the base directory from where looking for jeka.properties file
#   $2 : the property name
# Outputs:
#   Write env var name to stdout
#######################################
get_prop_value_from_base_dir() {
  local base_dir=$1
  local prop_name=$2

  # First look in command line args
  local cmd_args_value
  cmd_args_value="$(get_system_prop_from_args "$prop_name")"
  if [ "$cmd_args_value" != "" ]; then
    echo "$cmd_args_value"
    return 0
  fi

  # Then look in env variables
  local env_value
  env_value=$(printenv "$prop_name")
  if [ "$env_value" != "" ]; then
    echo "$env_value"
    return 0
  fi

  local value
  value=$(get_prop_value_from_file "$base_dir/jeka.properties" "$prop_name")
  if [ -z "$value" ]; then
    local parent_dir="$base_dir/.."
    local parent_jeka_props="$parent_dir/jeka.properties"
    if [ -f "$parent_jeka_props" ]; then
      get_prop_value_from_base_dir "$parent_dir" "$prop_name"
    else
      get_prop_value_from_file "$GLOBAL_PROP_FILE" "$prop_name"
    fi
    return 0
  fi
  echo "$value"
}

#######################################
# Returns the JAVA version to use according properties
# Globals:
#   CMD_LINE_ARGS (read)
#   JEKA_VERSION_PROP_NAME (read)
# Arguments:
#   $1 : the base directory from where looking for jeka.properties file
# Outputs:
#   Write JAVA version to stdout
#######################################
get_java_version_from_props() {
  local base_dir="$1"
  local version
  version=$(get_prop_value_from_base_dir "$base_dir" "$JEKA_VERSION_PROP_NAME")
  local trimmed_version
  trimmed_version="${version// /}"  # remove spaces
  echo "$trimmed_version"
}

#######################################
# Returns the JAVA version to use according properties
# Globals:
#   INTERPOLATED_ARGS (write)
# Arguments:
#   $@ : an array representing the original args
# Outputs:
#   result in INTERPOLATED_ARGS global args
#######################################
compute_INTERPOLATED_ARGS() {
  INTERPOLATED_ARGS=()
  for arg in "$@"; do
    if [[ $arg == ::* ]]; then   # if arg starts with '::'
      local token=${arg:2}
      local prop_name="jeka.cmd.$token"
      local value
      value=$(get_prop_value_from_base_dir "$DEFAULT_BASE_DIR" "$prop_name")
      if [ "$value" != "" ]; then

        # Value may content 0 or many elements
        # shellcheck disable=SC2206
        local substitute=($value)
        INTERPOLATED_ARGS+=("${substitute[@]}")
      else
        INTERPOLATED_ARGS+=("$arg")
      fi
    else
      INTERPOLATED_ARGS+=("$arg")
    fi
  done
}

#######################################
# Find the index of the remote option in an an array
# Globals:
#   INTERPOLATED_ARGS (write)
# Arguments:
#   $@ : an array representing the original args
# Outputs:
#   result in INTERPOLATED_ARGS global args
#######################################
find_remote_arg_index() {
  index=0
  for arg in "$@"; do
    is_remote_arg "$arg"
    if [ "$result" == "true" ]; then
      echo "$index"
      return 0;
    fi
    ((index++))
  done
  echo "-1";
}

#######################################
# Determines if the passed argument is a remote option (as -r)
# Arguments:
#   $1 : a string representing one argument
# Outputs:
#   result in 'result' global args
#######################################
is_remote_arg() {
  local arg="$1"
  if [[ "$arg" != -* ]]; then
    result="false"
    return 0
  fi
  local option=${arg:1}

  # check if option contains letter 'r' and optionally 'u' or 'p'
  if [[ "$option" == *r* ]] && [[ $option =~ ^(r?u?p?|r?u?p?)$ ]] && [[ ${#option} -le 3 ]]; then
    result="true"
  else
    result="false"
  fi
}

# call `get_jdk_home_from_props base_dir JAVA_VERSION`
get_jdk_home_from_props() {
  local base_dir=$1
  local jdk_version=$2
  local prop_name="jeka.jdk.$jdk_version"
  get_prop_value_from_base_dir "$base_dir" "$prop_name"
}

is_git_url() {
    if [[ $1 =~ ^(https://|ssh://|git://|git@).* ]]; then
        echo "true"
    else
        echo "false"
    fi
}

#######################################
# Returns the dir caching the specified git repo url
# Arguments:
#   $1 : a string representing the git repo url
# Outputs:
#   The dir location
#######################################
get_folder_name_from_git_url() {
    local url=$1
    local trimmed_url=$url
    local protocols=("https://" "ssh://" "git://" "git@")
    for protocol in "${protocols[@]}"; do
      trimmed_url="${trimmed_url#$protocol}"
    done
    local folder_name="${trimmed_url//\//_}"  # replace '/' by '_'
    echo "$folder_name"
}

assert_dir_exits() {
  if [ ! -d "$1" ]; then
    msg "Directory $1 does not exist"
    exit 1
  fi
}

#######################################
# Computes the base directory according the value of '-r' option.
# If the -r refers to a git repo url, then returns the dir where the repo is cloned.
# Global Vars:
#   BASE_DIR (write)
# Arguments:
#   $1 : a string representing a git repo url or a directory path
#   $2 : true/false for updating the cloned repo
# Outputs:
#   result in BASE_DIR global args
#######################################
compute_base_dir_from_resolved_remote_arg() {

  local remote_path="$1"  # file-system path or git url
  local should_clean="$2"
  local is_git_remote
  is_git_remote=$(is_git_url "$remote_path")

  # the remote reference a file-system path
  if [ "false" == "$is_git_remote" ]; then

    if [[ "$remote_path" == /* ]]; then    # absolute path
      result="$remote_path"
      assert_dir_exits "$result"
    else  # relative path
      result="$(pwd)/$remote_arg"
      assert_dir_exits "$result"
      result=$(cd "$result" && pwd)  # normalize pass
    fi
    BASE_DIR="$result"
    return 0
  fi

  ## Remote reference a git repo
  local git_url
  git_url=$(substring_before_hash "$remote_path")
  local git_tag
  git_tag=$(substring_after_hash "$remote_path")
  local branch_args=""
  if [ "$git_tag" != "" ]; then
    branch_args="--branch $git_tag"
  fi
  local cache_dir_name
  cache_dir_name=$(get_folder_name_from_git_url "$remote_path")
  result=$(get_git_cache_dir)/"$cache_dir_name"
  if [ "$should_clean" == "true" ]; then
    rm -rf "$result"
  fi
  if [ ! -d "$result" ]; then
      local quiet_flag="--quiet"
      if [ "$IS_VERBOSE" != "" ]; then
        quiet_flag=""
      fi
      info "Cloning $git_url into $result  ..."
      # $quiet_flag and $branch_args are not doubled-quoted on purpose (they may contains 0 or 2 args)
      # shellcheck disable=SC2086
      git clone $quiet_flag -c advice.detachedHead=false --depth 1 $branch_args "$git_url" "$result"
  else
      debug "Cache directory $result already exists. Won't clone or update."
  fi
  BASE_DIR=$result
}

#######################################
# Computes the base directory according presence or not of -r option
# Arguments:
#   $@ : array representing the interpolated command line
# Outputs:
#   result in BASE_DIR global args
#######################################
compute_BASE_DIR() {
  local -a array=( "$@" )
  local result
  local index
  index=$(find_remote_arg_index "${array[@]}")
  if [ "$index" == "-1" ]; then
    BASE_DIR=$(pwd)
    return 0
  fi
  local option=${array[(($index))]}
  local next_index=$((index + 1))
  local remote_arg=${array[$next_index]}
  local need_update="false"

  # check if cmdline contains -u or --update options, prior the -parameters
  local -a prior_program_option_array
  if [[ $PROGRAM_OPTION_INDEX == -1 ]]; then
    prior_program_option_array=("${INTERPOLATED_ARGS[@]}")
  else
    prior_program_option_array=("${INTERPOLATED_ARGS[@]:0:PROGRAM_OPTION_INDEX}")
  fi
  local contains_u
  contains_u=$(array_contains "-u" "${prior_program_option_array[@]}")
  local contains_update
  contains_update=$(array_contains "--update" "${prior_program_option_array[@]}")

  if [[ "$option" == *u* ]] || [[ $contains_u == "true" ]] || [[ $contains_update == "true" ]]; then
    need_update="true"
  fi
  compute_base_dir_from_resolved_remote_arg "$remote_arg" "$need_update"
}

#######################################
# Computes the location of JeKa distribution directory according the JeKa version
# used for the current BASE DIR. This may implies to dowload the distribution.
# Global Vars:
#   JEKA_DIST_DIR (write)
# Arguments:
#   $1 : the base directory
# Outputs:
#   result in JEKA_DIST_DIR global args
#######################################
compute_JEKA_DIST_DIR() {
  if [ "$JEKA_DIST_DIR" != "" ]; then
    return 0
  fi

  local base_dir=$1
  local explicit_distrib_dir
  explicit_distrib_dir=$(get_prop_value_from_base_dir "$base_dir" "jeka.distrib.location")
  if [ -n "$explicit_distrib_dir" ]; then
    JEKA_DIST_DIR="$explicit_distrib_dir"
  else
    local jeka_version=
    jeka_version=$(get_prop_value_from_base_dir "$base_dir" "jeka.version")
    if [ -z "$jeka_version" ]; then
      JEKA_DIST_DIR="$CURRENT_SCRIPT_DIR"  # if no version and distrib location specified, use the current script dir
    else
      local distrib_cache_dir
      distrib_cache_dir=$(get_cache_dir)/distributions/$jeka_version
      if [ -d "$distrib_cache_dir" ]; then
        JEKA_DIST_DIR="$distrib_cache_dir"

      else
        # select download repo
        local jeka_repo
        if [[ "$jeka_version" == *"-SNAPSHOT" ]]; then
          jeka_repo="https://oss.sonatype.org/content/repositories/snapshots"
        else
          jeka_repo="https://repo.maven.apache.org/maven2"
        fi
        local distrib_repo
        distrib_repo=$(get_prop_value_from_base_dir "$base_dir" "jeka.distrib.repo")
        [ -n "$distrib_repo" ] && jeka_repo=$distrib_repo

        local url=$jeka_repo/dev/jeka/jeka-core/$jeka_version/jeka-core-$jeka_version-distrib.zip
        info "Download Jeka distrib from $url in $distrib_cache_dir"
        download_and_unpack "$url" "$distrib_cache_dir"
        JEKA_DIST_DIR=$distrib_cache_dir
      fi
    fi
  fi
}

## Execute Jeka. Call `exec_jeka $base_dir`.
## Returns value in JEKA_CLASSPATH
compute_JEKA_CLASSPATH() {
  if [ "$JEKA_CLASSPATH" != "" ]; then
    return 0
  fi
  local dist_dir=$1
  local bin_dir="$dist_dir"

  # If no distrib dir is specified (no jeka.version specified), we look first
  # for jeka-core.jar presence in the same dir of the current script
  if [ -z "$dist_dir" ]; then  ## No jeka.version is specified, should find the local one
    if [ -f "$CURRENT_SCRIPT_DIR/$JEKA_JAR_NAME" ]; then
      bin_dir="$CURRENT_SCRIPT_DIR"
    fi
    if [ -z "$dist_dir" ]; then
      msg "No JeKa distribution found from script location $CURRENT_SCRIPT_DIR."
      msg "You probably forgot to mention a 'jeka.version' or 'jeka.distrib.location' property in jeka.properties file."
      exit 1
    fi
  fi

  local boot_dir_args

  ## Reference to remote found
  if [ "$REMOTE_BASE_DIR" != "" ]; then
    if [ -d "$REMOTE_BASE_DIR/jeka-boot" ]; then
         boot_dir_args="$REMOTE_BASE_DIR/jeka-boot/*:"
    fi

  ## No remote script, launch on current dir
  else
    if [ -d "./jeka-boot" ]; then
       boot_dir_args="./jeka-boot/*:"
    fi
  fi
  local jar_file="$dist_dir/bin/$JEKA_JAR_NAME"
  if [ ! -f "$jar_file" ]; then
    jar_file="$dist_dir/$JEKA_JAR_NAME"
  fi
  if [ ! -f "$jar_file" ]; then
    msg "Cannot find JeKa jar file $jar_file."
    msg "Are you sure the JeKa distribution you use is properly packaged ?"
    exit 1
  fi
  JEKA_CLASSPATH="$boot_dir_args$jar_file"
}

# call `get_or_download_jdk $JAVA_VERSION`. The result is set to DOWNLOAD_JDK_DIR var.
get_or_download_jdk() {
  local JAVA_VERSION="$1"
  local specified_distrib
  specified_distrib=$(get_prop_value_from_base_dir "$BASE_DIR" "jeka.java.distrib")
  if [ -n "$specified_distrib" ]; then
    JDK_DOWNLOAD_DISTRIB="$specified_distrib"
  fi
  local jdk_cache_dir
  jdk_cache_dir="$(get_cache_dir)/jdks/$JDK_DOWNLOAD_DISTRIB-$JAVA_VERSION"
  if [ ! -d "$jdk_cache_dir" ]; then
    if [ -z "$JDK_DOWNLOAD_OS" ]; then
      msg "Unable to download JDK, unsupported Operating System: $(uname -s)"
      msg "You may workaround this problem by specifying a 'jeka.jdk.$JAVA_VERSION' env var or property in ~/jeka/global.properties file."
      exit 1
    fi
    if [ -z "$JDK_DOWNLOAD_ARCH" ]; then
      msg "Unable to download JDK, unsupported Architecture: $(uname -m)"
      msg "You may workaround this problem by specifying a 'jeka.jdk.$JAVA_VERSION' env var or property in ~/jeka/global.properties file."
      exit 1
    fi
    local download_url="https://api.foojay.io/disco/v3.0/directuris?distro=$JDK_DOWNLOAD_DISTRIB&javafx_bundled=false&libc_type=$JDK_DOWNLOAD_LIBC_TYPE&archive_type=$JDK_DOWNLOAD_FILE_TYPE&operating_system=$JDK_DOWNLOAD_OS&package_type=jdk&version=$JAVA_VERSION&architecture=$JDK_DOWNLOAD_ARCH&latest=available"
    info "Downloading JDK $JDK_DOWNLOAD_DISTRIB $JAVA_VERSION to $jdk_cache_dir. It may take a while..."
    download_and_unpack "$download_url" "$jdk_cache_dir" "$JDK_DOWNLOAD_FILE_TYPE"
    if [ "tar.gz" == "$JDK_DOWNLOAD_FILE_TYPE" ]; then
      pushd "$jdk_cache_dir" > /dev/null 2>&1
      local nested_dir
      nested_dir=$(find "." -mindepth 1 -maxdepth 1 -type d | head -n 1 | cut -c 3-)
      popd > /dev/null 2>&1
      temp_dir=$(mktemp -d)
      if [ "$JDK_DOWNLOAD_OS" = "mac" ]; then
          nested_dir+="/Contents/Home"
      fi
      mv "$jdk_cache_dir"/"$nested_dir"/* "$temp_dir"
      mv "$temp_dir"/* "$jdk_cache_dir"
    fi
  fi
  DOWNLOAD_JDK_DIR=$jdk_cache_dir
}

#######################################
# Computes Java command according version, distrib, os and arch, implying optional
# JDK download
# Arguments:
# Global vars:
#    JDK_DOWNLOAD_OS
#    JDK_DOWNLOAD_LIBC_TYPE
#    JDK_DOWNLOAD_ARCH
#    JAVA_VERSION
#    JAVA_HOME
#    DEFAULT_JAVA_VERSION (read)
#    JEKA_JDK_HOME
#    IS_VERBOSE (read)
#    BASE_DIR (read)
#    JAVA_CMD
# Outputs:
#   result in BASE_DIR global args
#######################################
compute_JAVA_CMD() {
  if [ "$JAVA_CMD" != "" ]; then
    return 0;
  fi

  # OS specific support.  $var _must_ be set to either true or false.
  case "$(uname -s)" in
    Linux*)
      JDK_DOWNLOAD_OS="linux"
      if [ -f /etc/alpine-release ]; then
        JDK_DOWNLOAD_OS=alpine-linux
      fi
      ;;
    Darwin*)
      JDK_DOWNLOAD_OS="mac"
      JDK_DOWNLOAD_LIBC_TYPE="libc"; # necessary to download proper JDK
      ;;
  esac

  case "$(uname -m)" in
    i?86)
      JDK_DOWNLOAD_ARCH="x32";;
    x86_64|amd64)
      JDK_DOWNLOAD_ARCH="x64";;
    aarch64)
      JDK_DOWNLOAD_ARCH="aarch64";;
    armv7l)
      JDK_DOWNLOAD_ARCH="arm";;
    ppc64le)
      JDK_DOWNLOAD_ARCH="ppc64le";;
    s390x)
      JDK_DOWNLOAD_ARCH="s390x";;
    arm64)
      JDK_DOWNLOAD_ARCH="arm64"
      ;;
    *)
      JDK_DOWNLOAD_ARCH=""
      ;;
  esac

  # Determines JAVA_HOME
  JAVA_VERSION=$(get_java_version_from_props "$BASE_DIR")

  if [ -n "$JEKA_JDK_HOME" ]; then # We can enforce usage of a specific JDK by setting JEKA_JDK_HOME env var
    JAVA_HOME="$JEKA_JDK_HOME"

  elif [ -n "$JAVA_VERSION" ] || [ -z "$JAVA_HOME" ]; then # if a Java version is specified in then use one of the JeKa managed JDK
    if [ -z "$JAVA_VERSION" ]; then
      JAVA_VERSION=$"$DEFAULT_JAVA_VERSION"
      if [ -n "$IS_VERBOSE" ]; then
        info "No JAVA_HOME defined and no jeka.java.version defined. Use Java $DEFAULT_JAVA_VERSION."
      fi
    fi
    jdkPath=$(get_jdk_home_from_props "$BASE_DIR" "$JAVA_VERSION")
    debug "JDK HOME $JAVA_VERSION from env or props : $jdkPath "
    if [ -z "$jdkPath" ]; then
      get_or_download_jdk "$JAVA_VERSION"
      JAVA_HOME="$DOWNLOAD_JDK_DIR"
    fi
  fi

  # Determines JAVA_CMD to use according JAVA_HOME
  if [ -z "$JAVA_CMD" ] ; then
    if [ -n "$JAVA_HOME"  ] ; then
      if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
        # IBM's JDK on AIX uses strange locations for the executables
        JAVA_CMD="$JAVA_HOME/jre/sh/java"
      else
        JAVA_CMD="$JAVA_HOME/bin/java"
      fi
    else
      JAVA_CMD="$(which java)"
    fi
  fi

  if [ ! -x "$JAVA_CMD" ] ; then
    msg "Error: JAVA_HOME is not defined correctly (valued to $JAVA_HOME )."
    msg "  We cannot execute $JAVA_CMD" >&2
    msg "  You can specify which JDK to use by setting JEKA_JDK environment variable."
    exit 1
  fi

}

#######################################
# Execute java program if requested.
# Program execution is requested when '-p' is present in cmd line args.
# The args following '-p' are to be passed to program args.
# First, Jeka try to find an executable bin or jar, in 'jeka-output'
# If there is none, jeka launches build and retry.
#
# Global Vars:
#   BASE_DIR      (read)
#   JEKA_DIST_DIR (write)
#   RETRY_AFTER_BUILD (read/write)
#   INTERPOLATED_ARGS (read)
#   PROGRAM_OPTION_INDEX (read)
# Outputs:
#   None. Exit anyway if program launch has been requested
#######################################
execute_program_if_requested() {
  if [[ $PROGRAM_OPTION_INDEX == -1 ]]; then
    return 0
  fi
  local -i from_arg_index
  from_arg_index=$((PROGRAM_OPTION_INDEX+1))
  local program_args=("${INTERPOLATED_ARGS[@]:$from_arg_index}")
  execute_and_exit_native_if_present "${program_args[@]}"
  execute_and_exit_java_if_present "${program_args[@]}"

  if [[ "$RETRY_AFTER_BUILD" == "true" ]]; then
    msg "Cannot find a native or jar executable in $BASE_DIR/jeka-output"
    exit 1
  fi

  ## If we are here, this means that no native or jar has been found -> build
  debug "Launch a build to generate executable"
  compute_JAVA_CMD
  compute_JEKA_DIST_DIR "$BASE_DIR"
  compute_JEKA_CLASSPATH "$JEKA_DIST_DIR"
  local -a heading_args=("${INTERPOLATED_ARGS[@]::$PROGRAM_OPTION_INDEX}")

  local build_cmd
  build_cmd=$(get_prop_value_from_base_dir "$BASE_DIR" "jeka.program.build")
  if [[ -z "$build_cmd" ]]; then
    if [ -d "$BASE_DIR/src" ]; then
      build_cmd="project: pack -Djeka.skip.tests=true --stderr"
    else
      build_cmd="base: pack -Djeka.skip.tests=true --stderr"
    fi
  fi

  # shellcheck disable=SC2206
  local -a build_args=($build_cmd)
  # shellcheck disable=SC2145
  info "Launch build with command : ${heading_args[@]} ${build_args[@]}"
  "$JAVA_CMD" "${JEKA_OPTS[@]}" "-Djeka.current.basedir=$BASE_DIR" -cp "$JEKA_CLASSPATH" "dev.jeka.core.tool.Main" "${heading_args[@]}" "${build_args[@]}"
  RETRY_AFTER_BUILD="true"
  execute_program_if_requested

}

#######################################
# Gets the index of '-p' or '--program' in the given array
# Returns -1, if no such element found
# Globals:
#   none
# Arguments:
#   $1 : the arrays where we are searching element in
#   $2 : the array providing elements to search
# Outputs:
#   Write to stdout
#######################################
compute_PROGRAM_OPTION_INDEX() {
  local -i index=0
  local -a items=("$@")
  for item in "${items[@]}"; do
    if [ "$item" == "-p" ] || [ "$item" == "--program" ]; then
      PROGRAM_OPTION_INDEX="$index"
      return 0
    fi
    ((index += 1))

  done
  PROGRAM_OPTION_INDEX=-1
}

######################################
# Execute and exit native program if present
#
# Global Vars:
#   BASE_DIR      (read)
# Arguments:
#   $1 : args array to pass to native program
# Outputs:
#   None. Exit anyway if program found
#######################################
execute_and_exit_native_if_present() {
  local exe_file;
  for file in "$BASE_DIR"/jeka-output/*; do
      if [ -f "$file" ] && [ -x "$file" ] && [[ "$file" != *".jar" ]]; then
        exe_file="$file"
        break
      fi
  done
  if [ "$exe_file" == "" ]; then
    debug "No native exe file found in $BASE_DIR/jeka-output/*"
    return 0
  fi
  exec "$exe_file" "$@"
  exit $?
}

######################################
# Execute and exit java program if present
#
# Global Vars:
#   BASE_DIR      (read)
# Arguments:
#   $1 : args array to pass to native program
# Outputs:
#   None. Exit anyway if program found
#######################################
execute_and_exit_java_if_present() {
  local jar_file;
  for file in "$BASE_DIR"/jeka-output/*; do
      if [ -f "$file" ] && [[ "$file" == *".jar" ]]; then
        jar_file="$file"
        break
      fi
  done
  if [ "$jar_file" == "" ]; then
    debug "No Jar file found in $BASE_DIR/jeka-output/*"
    return 0
  fi
  compute_JAVA_CMD
  local -a sysProp_params
  filter_in_sysProp "$@"
  sysProp_params=("${returned[@]}")
  local -a regular_params
  filter_out_sysProp "$@"
  regular_params=("${returned[@]}")
  exec "$JAVA_CMD" "${sysProp_params[@]}" -jar "$jar_file" "${regular_params[@]}"
  exit $?
}

######################################
# Filter array keeping only items that match '-Dxxx=yyy' (sys prop)
#
# Global Vars:
#   returned     (write)
# Arguments:
#   $@ : arrays to filter
# Outputs:
#   The filtered array is written to in the 'returned' global var
#######################################
filter_in_sysProp() {
  local arr=("$@")
    returned=()
    for i in "${arr[@]}"; do
      if [[ $i == -D* ]] && [[ $i == *"="* ]]; then
        returned+=("$i")
      fi
    done
}

######################################
# Filter array removing items that match '-Dxxx=yyy' (sys prop)
#
# Global Vars:
#   returned     (write)
# Arguments:
#   $@ : arrays to filter
# Outputs:
#   The filtered array is written to in the 'returned' global var
#######################################
filter_out_sysProp() {
  local arr=("$@")
    returned=()
    for i in "${arr[@]}"; do
      if [[ $i != -D* ]] || [[ $i != *"="* ]]; then
        returned+=("$i")
      fi
    done
}

##############################################################
# Script starts here
##############################################################

compute_VERBOSE_QUIET
JEKA_USER_HOME=$(get_jeka_user_home)
GLOBAL_PROP_FILE="$JEKA_USER_HOME/global.properties"

compute_INTERPOLATED_ARGS "${CMD_LINE_ARGS[@]}"
compute_PROGRAM_OPTION_INDEX "${INTERPOLATED_ARGS[@]}"
compute_BASE_DIR "${INTERPOLATED_ARGS[@]}"

execute_program_if_requested

compute_JAVA_CMD

## When debugging we don't want to execute Jeka
if [ -z "$DRY_RUN" ]; then
  compute_JEKA_DIST_DIR "$BASE_DIR"
  compute_JEKA_CLASSPATH "$JEKA_DIST_DIR"

  exec "$JAVA_CMD" "${JEKA_OPTS[@]}" "-Djeka.current.basedir=$BASE_DIR" -cp "$JEKA_CLASSPATH" "dev.jeka.core.tool.Main" "$@"
fi