#!/bin/sh

set -e

SCRIPT=$(readlink $0 || true)
if [ -z $SCRIPT ]; then
    SCRIPT=$0
fi;
SCRIPT_DIR="$(cd `dirname "$SCRIPT"` && pwd -P)"
RELEASE_ROOT_DIR="$(cd "$SCRIPT_DIR/.." && pwd -P)"
REL_NAME="{{ rel_name }}"
REL_VSN="{{ rel_vsn }}"
ERTS_VSN="{{ erts_vsn }}"
CODE_LOADING_MODE="${CODE_LOADING_MODE:-embedded}"
REL_DIR="$RELEASE_ROOT_DIR/releases/$REL_VSN"
ERL_OPTS="{{ erl_opts }}"
RUNNER_LOG_DIR="${RUNNER_LOG_DIR:-$RELEASE_ROOT_DIR/log}"

find_erts_dir() {
    __erts_dir="$RELEASE_ROOT_DIR/erts-$ERTS_VSN"
    if [ -d "$__erts_dir" ]; then
        ERTS_DIR="$__erts_dir";
        ROOTDIR="$RELEASE_ROOT_DIR"
    else
        __erl="$(which erl)"
        code="io:format(\"~s\", [code:root_dir()]), halt()."
        __erl_root="$("$__erl" -noshell -eval "$code")"
        ERTS_DIR="$__erl_root/erts-$ERTS_VSN"
        ROOTDIR="$__erl_root"
    fi
}

# Get node pid
relx_get_pid() {
    if output="$(relx_nodetool rpcterms os getpid)"
    then
        echo "$output" | sed -e 's/"//g'
        return 0
    else
        echo "$output"
        return 1
    fi
}

relx_get_longname() {
    id="longname$(relx_gen_id)-${NAME}"
    "$BINDIR/erl" -boot start_clean -eval 'io:format("~s~n", [node()]), halt()' -noshell -name $id | sed -e 's/.*@//g'
}

# Connect to a remote node
relx_rem_sh() {
    # Generate a unique id used to allow multiple remsh to the same node
    # transparently
    id="remsh$(relx_gen_id)-${NAME}"

    # Get the node's ticktime so that we use the same thing.
    TICKTIME="$(relx_nodetool rpcterms net_kernel get_net_ticktime)"

    # Setup remote shell command to control node
    exec "$BINDIR/erl" "$NAME_TYPE" "$id" -remsh "$NAME" -boot start_clean \
         -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
         -setcookie "$COOKIE" -kernel net_ticktime $TICKTIME
}

# Generate a random id
relx_gen_id() {
    od -X -N 4 /dev/urandom | head -n1 | awk '{print $2}'
}

# Control a node
relx_nodetool() {
    command="$1"; shift

    "$ERTS_DIR/bin/escript" "$ROOTDIR/bin/nodetool" "$NAME_TYPE" "$NAME" \
                                -setcookie "$COOKIE" "$command" $@
}

# Run an escript in the node's environment
relx_escript() {
    shift; scriptpath="$1"; shift
    export RELEASE_ROOT_DIR

    "$ERTS_DIR/bin/escript" "$ROOTDIR/$scriptpath" $@
}

# Output a start command for the last argument of run_erl
relx_start_command() {
    printf "exec \"%s\" \"%s\"" "$RELEASE_ROOT_DIR/bin/$REL_NAME" \
           "$START_OPTION"
}

# Use $CWD/vm.args if exists, otherwise releases/VSN/vm.args
if [ -z "$VMARGS_PATH" ]; then
    if [ -f "$RELEASE_ROOT_DIR/vm.args" ]; then
        VMARGS_PATH="$RELEASE_ROOT_DIR/vm.args"
    else
        VMARGS_PATH="$REL_DIR/vm.args"
    fi
fi

if [ $RELX_REPLACE_OS_VARS ]; then
    awk '{while(match($0,"[$]{[^}]*}")) {var=substr($0,RSTART+2,RLENGTH -3);gsub("[$]{"var"}",ENVIRON[var])}}1' < $VMARGS_PATH > $VMARGS_PATH.2.config
    VMARGS_PATH=$VMARGS_PATH.2.config
fi

# Make sure log directory exists
mkdir -p "$RUNNER_LOG_DIR"

# Use $CWD/sys.config if exists, otherwise releases/VSN/sys.config
if [ -z "$RELX_CONFIG_PATH" ]; then
    if [ -f "$RELEASE_ROOT_DIR/sys.config" ]; then
        RELX_CONFIG_PATH="$RELEASE_ROOT_DIR/sys.config"
    else
        RELX_CONFIG_PATH="$REL_DIR/sys.config"
    fi
fi

if [ $RELX_REPLACE_OS_VARS ]; then
    awk '{while(match($0,"[$]{[^}]*}")) {var=substr($0,RSTART+2,RLENGTH -3);gsub("[$]{"var"}",ENVIRON[var])}}1' < $RELX_CONFIG_PATH > $RELX_CONFIG_PATH.2.config
    RELX_CONFIG_PATH=$RELX_CONFIG_PATH.2.config
fi

# Extract the target node name from node.args
NAME_ARG=$(egrep '^-s?name' "$VMARGS_PATH" || true)
if [ -z "$NAME_ARG" ]; then
    echo "vm.args needs to have either -name or -sname parameter."
    exit 1
fi

# Extract the name type and name from the NAME_ARG for REMSH
NAME_TYPE="$(echo "$NAME_ARG" | awk '{print $1}')"
NAME="$(echo "$NAME_ARG" | awk '{print $2}')"

PIPE_DIR="${PIPE_DIR:-/tmp/erl_pipes/$NAME/}"

# Extract the target cookie
COOKIE_ARG="$(grep '^-setcookie' "$VMARGS_PATH" || true)"
if [ -z "$COOKIE_ARG" ]; then
    echo "vm.args needs to have a -setcookie parameter."
    exit 1
fi

# Extract cookie name from COOKIE_ARG
COOKIE="$(echo "$COOKIE_ARG" | awk '{print $2}')"

find_erts_dir
export ROOTDIR="$RELEASE_ROOT_DIR"
export BINDIR="$ERTS_DIR/bin"
export EMU="beam"
export PROGNAME="erl"
export LD_LIBRARY_PATH="$ERTS_DIR/lib:$LD_LIBRARY_PATH"
ERTS_LIB_DIR="$ERTS_DIR/../lib"

cd "$ROOTDIR"

# User can specify an sname without @hostname
# This will fail when creating remote shell
# So here we check for @ and add @hostname if missing
case $NAME in
    *@*)
        # Nothing to do
        ;;
    *)
        # Add @hostname
        case $NAME_TYPE in
             -sname)
                 NAME=$NAME@`hostname -s`
                 ;;
             -name)
                 NAME=$NAME@$(relx_get_longname)
                 ;;
        esac
        ;;
esac

# Check the first argument for instructions
case "$1" in
    start|start_boot)

        # Make sure there is not already a node running
        #RES=`$NODETOOL ping`
        #if [ "$RES" = "pong" ]; then
        #    echo "Node is already running!"
        #    exit 1
        #fi
        # Save this for later.
        CMD=$1
        case "$1" in
            start)
                shift
                START_OPTION="console"
                HEART_OPTION="start"
                ;;
            start_boot)
                shift
                START_OPTION="console_boot"
                HEART_OPTION="start_boot"
                ;;
        esac
        RUN_PARAM="$@"

        # Set arguments for the heart command
        set -- "$SCRIPT_DIR/$REL_NAME" "$HEART_OPTION"
        [ "$RUN_PARAM" ] && set -- "$@" "$RUN_PARAM"

        # Export the HEART_COMMAND
        HEART_COMMAND="$RELEASE_ROOT_DIR/bin/$REL_NAME $CMD"
        export HEART_COMMAND

        mkdir -p "$PIPE_DIR"

        "$BINDIR/run_erl" -daemon "$PIPE_DIR" "$RUNNER_LOG_DIR" \
                          "$(relx_start_command)"
        ;;

    stop)
        # Wait for the node to completely stop...
        PID="$(relx_get_pid)"
        if ! relx_nodetool "stop"; then
            exit 1
        fi
        while $(kill -s 0 "$PID" 2>/dev/null);
        do
            sleep 1
        done
        ;;

    restart)
        ## Restart the VM without exiting the process
        if ! relx_nodetool "restart"; then
            exit 1
        fi
        ;;

    reboot)
        ## Restart the VM completely (uses heart to restart it)
        if ! relx_nodetool "reboot"; then
            exit 1
        fi
        ;;

    pid)
        ## Get the VM's pid
        if ! relx_get_pid; then
            exit 1
        fi
        ;;

    ping)
        ## See if the VM is alive
        if ! relx_nodetool "ping"; then
            exit 1
        fi
        ;;

    escript)
        ## Run an escript under the node's environment
        if ! relx_escript $@; then
            exit 1
        fi
        ;;

    attach)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        shift
        exec "$BINDIR/to_erl" "$PIPE_DIR"
        ;;

    remote_console)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        shift
        relx_rem_sh
        ;;

    upgrade|downgrade|install)
        if [ -z "$2" ]; then
            echo "Missing package argument"
            echo "Usage: $REL_NAME $1 {package base name}"
            echo "NOTE {package base name} MUST NOT include the .tar.gz suffix"
            exit 1
        fi

        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        exec "$BINDIR/escript" "$ROOTDIR/bin/install_upgrade.escript" \
             "install" "$REL_NAME" "$NAME" "$COOKIE" "$2"
        ;;

    unpack)
        if [ -z "$2" ]; then
            echo "Missing package argument"
            echo "Usage: $REL_NAME $1 {package base name}"
            echo "NOTE {package base name} MUST NOT include the .tar.gz suffix"
            exit 1
        fi

        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        exec "$BINDIR/escript" "$ROOTDIR/bin/install_upgrade.escript" \
             "unpack" "$REL_NAME" "$NAME" "$COOKIE" "$2"
        ;;

    console|console_clean|console_boot)
        # .boot file typically just $REL_NAME (ie, the app name)
        # however, for debugging, sometimes start_clean.boot is useful.
        # For e.g. 'setup', one may even want to name another boot script.
        case "$1" in
            console)
                if [ -f "$REL_DIR/$REL_NAME.boot" ]; then
                  BOOTFILE="$REL_DIR/$REL_NAME"
                else
                  BOOTFILE="$REL_DIR/start"
                fi
                ;;
            console_clean)
                BOOTFILE="$ROOTDIR/bin/start_clean"
                ;;
            console_boot)
                shift
                BOOTFILE="$1"
                shift
                ;;
        esac
        # Setup beam-required vars
        EMU="beam"
        PROGNAME="${0#*/}"

        export EMU
        export PROGNAME

        # Store passed arguments since they will be erased by `set`
        ARGS="$@"

        # Build an array of arguments to pass to exec later on
        # Build it here because this command will be used for logging.
        set -- "$BINDIR/erlexec" -boot "$BOOTFILE" \
            -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
            -config "$RELX_CONFIG_PATH" \
            -args_file "$VMARGS_PATH"

        # Dump environment info for logging purposes
        echo "Exec: $@" -- ${1+$ARGS}
        echo "Root: $ROOTDIR"

        # Log the startup
        echo "$RELEASE_ROOT_DIR"
        logger -t "$REL_NAME[$$]" "Starting up"

        # Start the VM
        exec "$@" -- ${1+$ARGS}
        ;;

    foreground)
        # start up the release in the foreground for use by runit
        # or other supervision services

        [ -f "$REL_DIR/$REL_NAME.boot" ] && BOOTFILE="$REL_NAME" || BOOTFILE=start
        FOREGROUNDOPTIONS="-noshell -noinput +Bd"

        # Setup beam-required vars
        EMU=beam
        PROGNAME="${0#*/}"

        export EMU
        export PROGNAME

        # Store passed arguments since they will be erased by `set`
        ARGS="$@"

        # Build an array of arguments to pass to exec later on
        # Build it here because this command will be used for logging.
        set -- "$BINDIR/erlexec" $FOREGROUNDOPTIONS \
            -boot "$REL_DIR/$BOOTFILE" -mode "$CODE_LOADING_MODE" -config "$RELX_CONFIG_PATH" \
            -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
            -args_file "$VMARGS_PATH"

        # Dump environment info for logging purposes
        echo "Exec: $@" -- ${1+$ARGS}
        echo "Root: $ROOTDIR"

        # Start the VM
        exec "$@" -- ${1+$ARGS}
        ;;
    rpc)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        shift

        relx_nodetool rpc $@
        ;;
    rpcterms)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        shift

        relx_nodetool rpcterms $@
        ;;

    *)
        echo "Usage: $REL_NAME {start|start_boot <file>|foreground|stop|restart|reboot|pid|ping|console|console_clean|console_boot <file>|attach|remote_console|upgrade|escript|rpc|rpcterms}"
        exit 1
        ;;
esac

exit 0