#!/usr/bin/env bash

#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
#
#    http://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.
#

#
# Shell script for starting the Spark Shell REPL
# Note that it will set MASTER to spark://${SPARK_MASTER_IP}:${SPARK_MASTER_PORT}
# if those two env vars are set in spark-env.sh but MASTER is not.

cygwin=false
case "`uname`" in
    CYGWIN*) cygwin=true;;
esac

# Enter posix mode for bash
set -o posix

CORE_PATTERN="^[0-9]+$"
MEM_PATTERN="^[0-9]+[m|g|M|G]$"

FWDIR="$(cd `dirname $0`/..; pwd)"

if [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
	echo "Usage: spark-shell [OPTIONS]"
	echo "OPTIONS:"
	echo "-c --cores num, the maximum number of cores to be used by the spark shell"
	echo "-em --execmem num[m|g], the memory used by each executor of spark shell"
	echo "-dm --drivermem num[m|g], the memory used by the spark shell and driver"
	echo "-h --help, print this help information" 
	exit
fi

for o in "$@"; do
  if [ "$1" = "-c" -o "$1" = "--cores" ]; then
    shift
    if [[ "$1" =~ $CORE_PATTERN ]]; then
      SPARK_REPL_OPTS="$SPARK_REPL_OPTS -Dspark.cores.max=$1"
      shift
    else
      echo "ERROR: wrong format for -c/--cores"
      exit 1
    fi
  fi
  if [ "$1" = "-em" -o "$1" = "--execmem" ]; then
    shift
    if [[ $1 =~ $MEM_PATTERN ]]; then
      SPARK_REPL_OPTS="$SPARK_REPL_OPTS -Dspark.executor.memory=$1"
      shift
    else
      echo "ERROR: wrong format for --execmem/-em"
      exit 1
    fi
  fi
  if [ "$1" = "-dm" -o "$1" = "--drivermem" ]; then
    shift
    if [[ $1 =~ $MEM_PATTERN ]]; then
      export SPARK_DRIVER_MEMORY=$1
      shift
    else
      echo "ERROR: wrong format for --drivermem/-dm"
      exit 1
    fi
  fi
done

# Set MASTER from spark-env if possible
DEFAULT_SPARK_MASTER_PORT=7077
if [ -z "$MASTER" ]; then
  . $FWDIR/bin/load-spark-env.sh
  if [ "x" != "x$SPARK_MASTER_IP" ]; then
    if [ "y" != "y$SPARK_MASTER_PORT" ]; then
      SPARK_MASTER_PORT="${SPARK_MASTER_PORT}"
    else
      SPARK_MASTER_PORT=$DEFAULT_SPARK_MASTER_PORT
    fi
    export MASTER="spark://${SPARK_MASTER_IP}:${SPARK_MASTER_PORT}"
  fi
fi

# Copy restore-TTY-on-exit functions from Scala script so spark-shell exits properly even in
# binary distribution of Spark where Scala is not installed
exit_status=127
saved_stty=""

# restore stty settings (echo in particular)
function restoreSttySettings() {
  stty $saved_stty
  saved_stty=""
}

function onExit() {
  if [[ "$saved_stty" != "" ]]; then
    restoreSttySettings
  fi
  exit $exit_status
}

# to reenable echo if we are interrupted before completing.
trap onExit INT

# save terminal settings
saved_stty=$(stty -g 2>/dev/null)
# clear on error so we don't later try to restore them
if [[ ! $? ]]; then
  saved_stty=""
fi

if $cygwin; then
  # Workaround for issue involving JLine and Cygwin
  # (see http://sourceforge.net/p/jline/bugs/40/).
  # If you're using the Mintty terminal emulator in Cygwin, may need to set the
  # "Backspace sends ^H" setting in "Keys" section of the Mintty options
  # (see https://github.com/sbt/sbt/issues/562).
  stty -icanon min 1 -echo > /dev/null 2>&1
  export SPARK_REPL_OPTS="$SPARK_REPL_OPTS -Djline.terminal=unix"
  $FWDIR/bin/spark-class org.apache.spark.repl.Main "$@"
  stty icanon echo > /dev/null 2>&1
else
  export SPARK_REPL_OPTS
  $FWDIR/bin/spark-class org.apache.spark.repl.Main "$@"
fi

# record the exit status lest it be overwritten:
# then reenable echo and propagate the code.
exit_status=$?
onExit