#!/usr/bin/env bash
#
# A more capable sbt runner, coincidentally also called sbt.
# Author: Paul Phillips 

set -o pipefail

# todo - make this dynamic
declare -r sbt_release_version="0.13.9"
declare -r sbt_unreleased_version="0.13.9"
declare -r buildProps="project/build.properties"

declare sbt_jar sbt_dir sbt_create sbt_version
declare scala_version sbt_explicit_version
declare verbose noshare batch trace_level log_level
declare sbt_saved_stty debugUs

echoerr () { echo >&2 "$@"; }
vlog ()    { [[ -n "$verbose" ]] && echoerr "$@"; }

# spaces are possible, e.g. sbt.version = 0.13.0
build_props_sbt () {
  [[ -r "$buildProps" ]] && \
    grep '^sbt\.version' "$buildProps" | tr '=\r' ' ' | awk '{ print $2; }'
}

update_build_props_sbt () {
  local ver="$1"
  local old="$(build_props_sbt)"

  [[ -r "$buildProps" ]] && [[ "$ver" != "$old" ]] && {
    perl -pi -e "s/^sbt\.version\b.*\$/sbt.version=${ver}/" "$buildProps"
    grep -q '^sbt.version[ =]' "$buildProps" || printf "\nsbt.version=%s\n" "$ver" >> "$buildProps"

    vlog "!!!"
    vlog "!!! Updated file $buildProps setting sbt.version to: $ver"
    vlog "!!! Previous value was: $old"
    vlog "!!!"
  }
}

set_sbt_version () {
  sbt_version="${sbt_explicit_version:-$(build_props_sbt)}"
  [[ -n "$sbt_version" ]] || sbt_version=$sbt_release_version
  export sbt_version
}

# restore stty settings (echo in particular)
onSbtRunnerExit() {
  [[ -n "$sbt_saved_stty" ]] || return
  vlog ""
  vlog "restoring stty: $sbt_saved_stty"
  stty "$sbt_saved_stty"
  unset sbt_saved_stty
}

# save stty and trap exit, to ensure echo is reenabled if we are interrupted.
trap onSbtRunnerExit EXIT
sbt_saved_stty="$(stty -g 2>/dev/null)"
vlog "Saved stty: $sbt_saved_stty"

# this seems to cover the bases on OSX, and someone will
# have to tell me about the others.
get_script_path () {
  local path="$1"
  [[ -L "$path" ]] || { echo "$path" ; return; }

  local target="$(readlink "$path")"
  if [[ "${target:0:1}" == "/" ]]; then
    echo "$target"
  else
    echo "${path%/*}/$target"
  fi
}

die() {
  echo "Aborting: $@"
  exit 1
}

make_url () {
  version="$1"

  case "$version" in
        0.7.*) echo "http://simple-build-tool.googlecode.com/files/sbt-launch-0.7.7.jar" ;;
      0.10.* ) echo "$sbt_launch_repo/org.scala-tools.sbt/sbt-launch/$version/sbt-launch.jar" ;;
    0.11.[12]) echo "$sbt_launch_repo/org.scala-tools.sbt/sbt-launch/$version/sbt-launch.jar" ;;
            *) echo "$sbt_launch_repo/org.scala-sbt/sbt-launch/$version/sbt-launch.jar" ;;
  esac
}

init_default_option_file () {
  local overriding_var="${!1}"
  local default_file="$2"
  if [[ ! -r "$default_file" && "$overriding_var" =~ ^@(.*)$ ]]; then
    local envvar_file="${BASH_REMATCH[1]}"
    if [[ -r "$envvar_file" ]]; then
      default_file="$envvar_file"
    fi
  fi
  echo "$default_file"
}

declare -r cms_opts="-XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC"
declare -r jit_opts="-XX:ReservedCodeCacheSize=256m -XX:+TieredCompilation"
declare -r default_jvm_opts_common="-Xms512m -Xmx1536m -Xss2m $jit_opts $cms_opts"
declare -r noshare_opts="-Dsbt.global.base=project/.sbtboot -Dsbt.boot.directory=project/.boot -Dsbt.ivy.home=project/.ivy"
declare -r latest_28="2.8.2"
declare -r latest_29="2.9.3"
declare -r latest_210="2.10.5"
declare -r latest_211="2.11.7"
declare -r latest_212="2.12.0-M3"

declare -r script_path="$(get_script_path "$BASH_SOURCE")"
declare -r script_name="${script_path##*/}"

# some non-read-onlies set with defaults
declare java_cmd="java"
declare sbt_opts_file="$(init_default_option_file SBT_OPTS .sbtopts)"
declare jvm_opts_file="$(init_default_option_file JVM_OPTS .jvmopts)"
declare sbt_launch_repo="http://repo.typesafe.com/typesafe/ivy-releases"

# pull -J and -D options to give to java.
declare -a residual_args
declare -a java_args
declare -a scalac_args
declare -a sbt_commands

# args to jvm/sbt via files or environment variables
declare -a extra_jvm_opts extra_sbt_opts

addJava () {
  vlog "[addJava] arg = '$1'"
  java_args+=("$1")
}
addSbt () {
  vlog "[addSbt] arg = '$1'"
  sbt_commands+=("$1")
}
setThisBuild () {
  vlog "[addBuild] args = '$@'"
  local key="$1" && shift
  addSbt "set $key in ThisBuild := $@"
}
addScalac () {
  vlog "[addScalac] arg = '$1'"
  scalac_args+=("$1")
}
addResidual () {
  vlog "[residual] arg = '$1'"
  residual_args+=("$1")
}
addResolver () {
  addSbt "set resolvers += $1"
}
addDebugger () {
  addJava "-Xdebug"
  addJava "-Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=$1"
}
setScalaVersion () {
  [[ "$1" == *"-SNAPSHOT" ]] && addResolver 'Resolver.sonatypeRepo("snapshots")'
  addSbt "++ $1"
}
setJavaHome () {
  java_cmd="$1/bin/java"
  setThisBuild javaHome "Some(file(\"$1\"))"
  export JAVA_HOME="$1"
  export JDK_HOME="$1"
  export PATH="$JAVA_HOME/bin:$PATH"
}
setJavaHomeQuietly () {
  addSbt warn
  setJavaHome "$1"
  addSbt info
}

# if set, use JDK_HOME/JAVA_HOME over java found in path
if [[ -e "$JDK_HOME/lib/tools.jar" ]]; then
  setJavaHomeQuietly "$JDK_HOME"
elif [[ -e "$JAVA_HOME/bin/java" ]]; then
  setJavaHomeQuietly "$JAVA_HOME"
fi

# directory to store sbt launchers
declare sbt_launch_dir="$HOME/.sbt/launchers"
[[ -d "$sbt_launch_dir" ]] || mkdir -p "$sbt_launch_dir"
[[ -w "$sbt_launch_dir" ]] || sbt_launch_dir="$(mktemp -d -t sbt_extras_launchers.XXXXXX)"

java_version () {
  local version=$("$java_cmd" -version 2>&1 | grep -E -e '(java|openjdk) version' | awk '{ print $3 }' | tr -d \")
  vlog "Detected Java version: $version"
  echo "${version:2:1}"
}

# MaxPermSize critical on pre-8 jvms but incurs noisy warning on 8+
default_jvm_opts () {
  local v="$(java_version)"
  if [[ $v -ge 8 ]]; then
    echo "$default_jvm_opts_common"
  else
    echo "-XX:MaxPermSize=384m $default_jvm_opts_common"
  fi
}

build_props_scala () {
  if [[ -r "$buildProps" ]]; then
    versionLine="$(grep '^build.scala.versions' "$buildProps")"
    versionString="${versionLine##build.scala.versions=}"
    echo "${versionString%% .*}"
  fi
}

execRunner () {
  # print the arguments one to a line, quoting any containing spaces
  vlog "# Executing command line:" && {
    for arg; do
      if [[ -n "$arg" ]]; then
        if printf "%s\n" "$arg" | grep -q ' '; then
          printf >&2 "\"%s\"\n" "$arg"
        else
          printf >&2 "%s\n" "$arg"
        fi
      fi
    done
    vlog ""
  }

  [[ -n "$batch" ]] && exec /dev/null; then
      curl --fail --silent --location "$url" --output "$jar"
    elif which wget >/dev/null; then
      wget --quiet -O "$jar" "$url"
    fi
  } && [[ -r "$jar" ]]
}

acquire_sbt_jar () {
  sbt_url="$(jar_url "$sbt_version")"
  sbt_jar="$(jar_file "$sbt_version")"

  [[ -r "$sbt_jar" ]] || download_url "$sbt_url" "$sbt_jar"
}

usage () {
  cat  0 )) || {
  vlog "Starting $script_name: invoke with -help for other options"
  residual_args=( shell )
}

# verify this is an sbt dir or -create was given
[[ -r ./build.sbt || -d ./project || -n "$sbt_create" ]] || {
  cat