#!/bin/bash

RUNNER_SCRIPT_DIR=$(cd ${0%/*} && pwd)

RUNNER_BASE_DIR=${RUNNER_SCRIPT_DIR%/*}
RUNNER_ETC_DIR=$RUNNER_BASE_DIR/etc
RUNNER_LOG_DIR=$RUNNER_BASE_DIR/log
PIPE_DIR=/tmp/$RUNNER_BASE_DIR/
RUNNER_USER=

# Make sure this script is running as the appropriate user
if [ ! -z "$RUNNER_USER" ] && [ `whoami` != "$RUNNER_USER" ]; then
    exec sudo -u $RUNNER_USER -i $0 $@
fi

# Make sure CWD is set to runner base dir
cd $RUNNER_BASE_DIR

# Make sure log directory exists
mkdir -p $RUNNER_LOG_DIR

# Extract the target node name from node.args
NAME_ARG=`grep -e '-[s]*name' $RUNNER_ETC_DIR/vm.args`
if [ -z "$NAME_ARG" ]; then
    echo "vm.args needs to have either -name or -sname parameter."
    exit 1
fi

# Extract the target cookie
COOKIE_ARG=`grep -e '-setcookie' $RUNNER_ETC_DIR/vm.args`
if [ -z "$COOKIE_ARG" ]; then
    echo "vm.args needs to have a -setcookie parameter."
    exit 1
fi

# Identify the script name
SCRIPT=`basename $0`

# Parse out release and erts info
START_ERL=`cat $RUNNER_BASE_DIR/releases/start_erl.data`
ERTS_VSN=${START_ERL% *}
APP_VSN=${START_ERL#* }

# Add ERTS bin dir to our path.
ERTS_PATH=$RUNNER_BASE_DIR/erts-$ERTS_VSN/bin

# Setup command to control the node
NODETOOL="$ERTS_PATH/escript $ERTS_PATH/nodetool $NAME_ARG $COOKIE_ARG"

# Check the first argument for instructions
case "$1" in
    start)
        # Make sure there is not already a node running
        RES=`$NODETOOL ping`
        if [ "$RES" == "pong" ]; then
            echo "Node is already running!"
            exit 1
        fi
        export HEART_COMMAND="$RUNNER_BASE_DIR/bin/$SCRIPT start"
        mkdir -p $PIPE_DIR
        $ERTS_PATH/run_erl -daemon $PIPE_DIR $RUNNER_LOG_DIR "exec $RUNNER_BASE_DIR/bin/$SCRIPT console" 2>&1
        ;;

    stop)
        # Wait for the node to completely stop...
        PID=`ps -ef|grep "$RUNNER_BASE_DIR/.*/[b]eam.smp|awk '{print $2}'"`
        $NODETOOL stop
        while `kill -0 $PID 2>/dev/null`;
        do
             sleep 1
        done
        ;;

    restart)
        ## Restart the VM without exiting the process
        $NODETOOL restart
        ;;

    reboot)
        ## Restart the VM completely (uses heart to restart it)
        $NODETOOL reboot
        ;;

    ping)
        ## See if the VM is alive
        $NODETOOL ping
        ;;

    attach)
        # Make sure a node IS running
        RES=`$NODETOOL ping`
        if [ "$RES" != "pong" ]; then
            echo "Node is not running!"
            exit 1
        fi

        shift
        $ERTS_PATH/to_erl $PIPE_DIR
        ;;

    console)
        RES=`$NODETOOL ping`
        if [ "$RES" == "pong" ]; then
            echo "Node is already running - use '$SCRIPT attach' instead"
            exit 1
        fi
        # Setup beam-required vars
        ROOTDIR=$RUNNER_BASE_DIR
        BINDIR=$ROOTDIR/erts-$ERTS_VSN/bin
        EMU=beam
        PROGNAME=`echo $0 | sed 's/.*\///'`
        CONFIG=""
        for f in `ls $RUNNER_ETC_DIR/*.config`; do CONFIG="$CONFIG -config $f"; done
        CMD="$BINDIR/erlexec -boot $RUNNER_BASE_DIR/releases/$APP_VSN/$SCRIPT -embedded $CONFIG -args_file $RUNNER_ETC_DIR/vm.args -- ${1+"$@"}"
        export EMU
        export ROOTDIR
        export BINDIR
        export PROGNAME

        # Dump environment info for logging purposes
        echo "Exec: $CMD"
        echo "Root: $ROOTDIR"

        # Log the startup
        logger -t "$SCRIPT[$$]" "Starting up"

        # Start the VM
        exec $CMD
        ;;

    *)
        echo "Usage: $SCRIPT {start|stop|restart|reboot|ping|console|attach}"
        exit 1
        ;;
esac

exit 0
