#!/bin/sh

# define default configuration
POLL=true
SMP=auto
ERL_MAX_PORTS=32000
ERL_PROCESSES=250000
ERL_MAX_ETS_TABLES=1400
FIREWALL_WINDOW=""
ERLANG_NODE=ejabberd@localhost

# define default environment variables
SCRIPT_DIR=`cd ${0%/*} && pwd`
ERL={{erl}}
IEX={{bindir}}/iex
EPMD={{epmd}}
INSTALLUSER={{installuser}}
ERL_LIBS={{libdir}}

# check the proper system user is used if defined
if [ "$INSTALLUSER" != "" ] ; then
    EXEC_CMD="false"
    for GID in `id -G`; do
        if [ $GID -eq 0 ] ; then
            INSTALLUSER_HOME=$(getent passwd "$INSTALLUSER" | cut -d: -f6)
            if [ -n "$INSTALLUSER_HOME" ] && [ ! -d "$INSTALLUSER_HOME" ] ; then
                mkdir -p "$INSTALLUSER_HOME"
                chown "$INSTALLUSER" "$INSTALLUSER_HOME"
            fi
            EXEC_CMD="as_install_user"
        fi
    done
    if [ `id -g` -eq `id -g $INSTALLUSER` ] ; then
        EXEC_CMD="as_current_user"
    fi
    if [ "$EXEC_CMD" = "false" ] ; then
        echo "This command can only be run by root or the user $INSTALLUSER" >&2
        exit 4
    fi
else
    EXEC_CMD="as_current_user"
fi

# run command either directly or via su $INSTALLUSER
exec_cmd()
{
    if [ "EXEC_CMD" = as_install_user ]; then
        su -c '"$0" $@"' "INSTALLUSER" -- "$@"
    else
        "$@"
    fi
}

# parse command line parameters
next=init
for arg; do
    # Empty argument list as it is already saved in the for buffer
    if [ "$next" = init ]; then
        next=
        set --
    fi
    case $next in
        node) ERLANG_NODE_ARG=$arg; next=;;
        config-dir) ETC_DIR=$arg; next=;;
        config) EJABBERD_CONFIG_PATH=$arg; next=;;
        ctl-config) EJABBERDCTL_CONFIG_PATH=$arg; next=;;
        logs) LOGS_DIR=$arg; next=;;
        spool) SPOOL_DIR=$arg; next=;;
        "")
            case $arg in
                --) next=raw;;
                --no-timeout) EJABBERD_NO_TIMEOUT="--no-timeout" ;;
                --node) next=node;;
                --config-dir) next=config-dir;;
                --config) next=config;;
                --ctl-config) next=ctl-config;;
                --logs) next=logs;;
                --spool) next=spool;;
                *) set -- "$@" "$arg";; # unknown option, keep it.
            esac;;
        raw) # we are after --, keep options as it is.
            set -- "$@" "$arg";;
    esac
done

# Define ejabberd variable if they have not been defined from the command line
if [ "$ETC_DIR" = "" ] ; then
    ETC_DIR={{sysconfdir}}/ejabberd
fi
if [ "$EJABBERDCTL_CONFIG_PATH" = "" ] ; then
    EJABBERDCTL_CONFIG_PATH=$ETC_DIR/ejabberdctl.cfg
fi
if [ -f "$EJABBERDCTL_CONFIG_PATH" ] ; then
    . "$EJABBERDCTL_CONFIG_PATH"
fi
if [ "$EJABBERD_CONFIG_PATH" = "" ] ; then
    EJABBERD_CONFIG_PATH=$ETC_DIR/ejabberd.yml
fi
if [ "$LOGS_DIR" = "" ] ; then
    LOGS_DIR={{localstatedir}}/log/ejabberd
fi
if [ "$SPOOL_DIR" = "" ] ; then
    SPOOL_DIR={{localstatedir}}/lib/ejabberd
fi
if [ "$EJABBERD_DOC_PATH" = "" ] ; then
    EJABBERD_DOC_PATH={{docdir}}
fi
if [ "$ERLANG_NODE_ARG" != "" ] ; then
    ERLANG_NODE=$ERLANG_NODE_ARG
fi
if [ "{{release}}" != "true" -a "$EJABBERD_BIN_PATH" = "" ] ; then
    EJABBERD_BIN_PATH={{libdir}}/ejabberd/priv/bin
fi
EJABBERD_LOG_PATH=$LOGS_DIR/ejabberd.log
DATETIME=`date "+%Y%m%d-%H%M%S"`
ERL_CRASH_DUMP=$LOGS_DIR/erl_crash_$DATETIME.dump
ERL_INETRC=$ETC_DIR/inetrc

# define mnesia options
MNESIA_OPTS="-mnesia dir \"$SPOOL_DIR\" $MNESIA_OPTIONS"
# define erl parameters
ERLANG_OPTS="+K $POLL -smp $SMP +P $ERL_PROCESSES $ERL_OPTIONS"
KERNEL_OPTS=""
if [ "$FIREWALL_WINDOW" != "" ] ; then
    KERNEL_OPTS="${KERNEL_OPTS} -kernel inet_dist_listen_min ${FIREWALL_WINDOW%-*} inet_dist_listen_max ${FIREWALL_WINDOW#*-}"
fi
if [ "$INET_DIST_INTERFACE" != "" ] ; then
    INET_DIST_INTERFACE2="$(echo $INET_DIST_INTERFACE | sed 's/\./,/g')"
    if [ "$INET_DIST_INTERFACE" != "$INET_DIST_INTERFACE2" ] ; then
        INET_DIST_INTERFACE2="{$INET_DIST_INTERFACE2}"
    fi
    KERNEL_OPTS="${KERNEL_OPTS} -kernel inet_dist_use_interface \"${INET_DIST_INTERFACE2}\""
fi
if [ "$ERLANG_NODE" = "${ERLANG_NODE%.*}" ] ; then
    NAME="-sname"
else
    NAME="-name"
fi
IEXNAME="-$NAME"

# define ejabberd environment parameters
if [ "$EJABBERD_CONFIG_PATH" != "${EJABBERD_CONFIG_PATH%.yml}" ] ; then
    rate=$(sed '/^[ 	]*log_rate_limit/!d;s/.*://;s/ *//' $EJABBERD_CONFIG_PATH)
    rotate=$(sed '/^[ 	]*log_rotate_size/!d;s/.*://;s/ *//' $EJABBERD_CONFIG_PATH)
    count=$(sed '/^[ 	]*log_rotate_count/!d;s/.*://;s/ *//' $EJABBERD_CONFIG_PATH)
    date=$(sed '/^[ 	]*log_rotate_date/!d;s/.*://;s/ *//' $EJABBERD_CONFIG_PATH)
else
    rate=$(sed '/^[ 	]*log_rate_limit/!d;s/.*,//;s/ *//;s/}\.//' $EJABBERD_CONFIG_PATH)
    rotate=$(sed '/^[ 	]*log_rotate_size/!d;s/.*,//;s/ *//;s/}\.//' $EJABBERD_CONFIG_PATH)
    count=$(sed '/^[ 	]*log_rotate_count/!d;s/.*,//;s/ *//;s/}\.//' $EJABBERD_CONFIG_PATH)
    date=$(sed '/^[ 	]*log_rotate_date/!d;s/.*,//;s/ *//;s/}\.//' $EJABBERD_CONFIG_PATH)
fi
[ -z "$rate" ] || EJABBERD_OPTS="log_rate_limit $rate"
[ -z "$rotate" ] || EJABBERD_OPTS="${EJABBERD_OPTS} log_rotate_size $rotate"
[ -z "$count" ] || EJABBERD_OPTS="${EJABBERD_OPTS} log_rotate_count $count"
[ -z "$date" ] || EJABBERD_OPTS="${EJABBERD_OPTS} log_rotate_date '$date'"
[ -z "$EJABBERD_OPTS" ] || EJABBERD_OPTS="-ejabberd ${EJABBERD_OPTS}"

[ -d "$SPOOL_DIR" ] || $EXEC_CMD "mkdir -p $SPOOL_DIR"
cd "$SPOOL_DIR"

# export global variables
export EJABBERD_CONFIG_PATH
export EJABBERD_LOG_PATH
export EJABBERD_BIN_PATH
export EJABBERD_DOC_PATH
export EJABBERD_PID_PATH
export ERL_CRASH_DUMP
export ERL_EPMD_ADDRESS
export ERL_INETRC
export ERL_MAX_PORTS
export ERL_MAX_ETS_TABLES
export CONTRIB_MODULES_PATH
export CONTRIB_MODULES_CONF_DIR
export ERL_LIBS

# TODO: Too much copy-and-paste below, factorize!
# start server
start()
{
    check_start
    exec_cmd $ERL \
             $NAME $ERLANG_NODE \
             -noinput -detached \
             $MNESIA_OPTS \
             $KERNEL_OPTS \
             $EJABBERD_OPTS \
             -s ejabberd \
             $ERLANG_OPTS \
             "$@"
}

# attach to server
debug()
{
    debugwarning
    NID=$(uid debug)
    exec_cmd $ERL $NAME $NID \
             -remsh $ERLANG_NODE \
             -hidden \
             $KERNEL_OPTS \
             $ERLANG_OPTS \
             "$@"
}

# attach to server using Elixir
iexdebug()
{
    debugwarning
    # Elixir shell is hidden as default
    NID=$(uid debug)
    exec_cmd $IEX $IEXNAME $NID \
             -remsh "$ERLANG_NODE" \
             --erl "$KERNEL_OPTS" \
             --erl "$ERLANG_OPTS" \
             --erl "$@"
}

# start interactive server
live()
{
    livewarning
    exec_cmd $ERL $NAME $ERLANG_NODE \
             $MNESIA_OPTS \
             $KERNEL_OPTS \
             $EJABBERD_OPTS \
             -s ejabberd \
             $ERLANG_OPTS \
             "$@"
}

# start interactive server with Elixir
iexlive()
{
    livewarning
    echo $@
    exec_cmd $IEX $IEXNAME $ERLANG_NODE \
         --erl "-mnesia dir \"$SPOOL_DIR\"" \
         --erl "$KERNEL_OPTS" \
         --erl "$EJABBERD_OPTS" \
         --app ejabberd \
         --erl "$ERLANG_OPTS" \
         --erl "$@"
}

# start server in the foreground
foreground()
{
    check_start
    exec_cmd $ERL $NAME $ERLANG_NODE \
         -noinput \
         $MNESIA_OPTS \
         $KERNEL_OPTS \
         $EJABBERD_OPTS \
         -s ejabberd \
         $ERLANG_OPTS \
         "$@"
}

debugwarning()
{
    if [ "$EJABBERD_BYPASS_WARNINGS" != "true" ] ; then
        echo "--------------------------------------------------------------------"
        echo ""
        echo "IMPORTANT: we will attempt to attach an INTERACTIVE shell"
        echo "to an already running ejabberd node."
        echo "If an ERROR is printed, it means the connection was not successful."
        echo "You can interact with the ejabberd node if you know how to use it."
        echo "Please be extremely cautious with your actions,"
        echo "and exit immediately if you are not completely sure."
        echo ""
        echo "To detach this shell from ejabberd, press:"
        echo "  control+c, control+c"
        echo ""
        echo "--------------------------------------------------------------------"
        echo "To bypass permanently this warning, add to ejabberdctl.cfg the line:"
        echo "  EJABBERD_BYPASS_WARNINGS=true"
        echo "Press return to continue"
        read foo
        echo ""
    fi
}

livewarning()
{
    check_start
    if [ "$EJABBERD_BYPASS_WARNINGS" != "true" ] ; then
        echo "--------------------------------------------------------------------"
        echo ""
        echo "IMPORTANT: ejabberd is going to start in LIVE (interactive) mode."
        echo "All log messages will be shown in the command shell."
        echo "You can interact with the ejabberd node if you know how to use it."
        echo "Please be extremely cautious with your actions,"
        echo "and exit immediately if you are not completely sure."
        echo ""
        echo "To exit this LIVE mode and stop ejabberd, press:"
        echo "  q().  and press the Enter key"
        echo ""
        echo "--------------------------------------------------------------------"
        echo "To bypass permanently this warning, add to ejabberdctl.cfg the line:"
        echo "  EJABBERD_BYPASS_WARNINGS=true"
        echo "Press return to continue"
        read foo
        echo ""
    fi
}

etop()
{
    NID=$(uid top)
    exec_cmd $ERL \
      $NAME $NID \
      -hidden -s etop -s erlang halt -output text -node $ERLANG_NODE
}

ping()
{
    [ -z "$1" ] && PEER=${ERLANG_NODE} || PEER=$1
    if [ "$PEER" = "${PEER%.*}" ] ; then
        PING_NAME="-sname"
        PING_NODE=$(hostname -s)
    else
        PING_NAME="-name"
        PING_NODE=$(hostname)
    fi
    NID=$(uid ping ${PING_NODE})
    exec_cmd $ERL \
             $PING_NAME $NID \
             -hidden $KERNEL_OPTS $ERLANG_OPTS \
             -eval 'io:format("~p~n",[net_adm:ping('"$PEER"')])' \
             -s erlang halt -output text -noinput
}

help()
{
    echo ""
    echo "Commands to start an ejabberd node:"
    echo "  start      Start an ejabberd node in server mode"
    echo "  debug      Attach an interactive Erlang shell to a running ejabberd node"
    echo "  iexdebug   Attach an interactive Elixir shell to a running ejabberd node"
    echo "  live       Start an ejabberd node in live (interactive) mode"
    echo "  iexlive    Start an ejabberd node in live (interactive) mode, within an Elixir shell"
    echo "  foreground Start an ejabberd node in server mode (attached)"
    echo ""
    echo "Optional parameters when starting an ejabberd node:"
    echo "  --config-dir dir   Config ejabberd:    $ETC_DIR"
    echo "  --config file      Config ejabberd:    $EJABBERD_CONFIG_PATH"
    echo "  --ctl-config file  Config ejabberdctl: $EJABBERDCTL_CONFIG_PATH"
    echo "  --logs dir         Directory for logs: $LOGS_DIR"
    echo "  --spool dir        Database spool dir: $SPOOL_DIR"
    echo "  --node nodename    ejabberd node name: $ERLANG_NODE"
    echo ""
}

# common control function
ctl()
{
    NID=$(uid ctl)
    exec_cmd $ERL $NAME $NID \
         -noinput -hidden $KERNEL_OPTS -s ejabberd_ctl \
         -extra $ERLANG_NODE $EJABBERD_NO_TIMEOUT \
         "$@"
    result=$?
    case $result in
        2) help;;
        3) help;;
        *) :;;
    esac
    return $result
}

uid()
{
    uuid=$(uuidgen 2>/dev/null)
    [ -z "$uuid" -a -f /proc/sys/kernel/random/uuid ] && \
        uuid=$(cat /proc/sys/kernel/random/uuid)
    [ -z "$uuid" ] && uuid=$(printf "%X" $RANDOM$(date +%M%S)$$)
    uuid=${uuid%%-*}
    [ $# -eq 0 ] && echo ${uuid}-${ERLANG_NODE}
    [ $# -eq 1 ] && echo ${uuid}-${1}-${ERLANG_NODE}
    [ $# -eq 2 ] && echo ${uuid}-${1}@${2}
}

# stop epmd if there is no other running node
stop_epmd()
{
    "$EPMD" -names 2>/dev/null | grep -q name || "$EPMD" -kill >/dev/null
}

# make sure node not already running and node name unregistered
check_start()
{
    "$EPMD" -names 2>/dev/null | grep -q " ${ERLANG_NODE%@*} " && {
        ps ux | grep -v grep | grep -q " $ERLANG_NODE " && {
            echo "ERROR: The ejabberd node '$ERLANG_NODE' is already running."
            exit 4
        } || {
            ps ux | grep -v grep | grep -q beam && {
                echo "ERROR: The ejabberd node '$ERLANG_NODE' is registered,"
                echo "       but no related beam process has been found."
                echo "Shutdown all other erlang nodes, and call 'epmd -kill'."
                exit 5
            } || {
                "$EPMD" -kill >/dev/null
            }
        }
    }
}

# allow sync calls
wait_for_status()
{
    # args: status try delay
    # return: 0 OK, 1 KO
    timeout=$2
    status=4
    while [ $status -ne $1 ] ; do
        sleep $3
        timeout=`expr $timeout - 1`
        [ $timeout -eq 0 ] && {
            status=$1
        } || {
            ctl status > /dev/null
            status=$?
        }
    done
    [ $timeout -eq 0 ] && return 1 || return 0
}

# main handler
case $@ in
    'start') start;;
    'debug') debug;;
    'iexdebug') iexdebug;;
    'live') live;;
    'iexlive') iexlive;;
    'foreground') foreground;;
    'ping'*) shift; ping "$@";;
    'etop') etop;;
    'started') wait_for_status 0 30 2;; # wait 30x2s before timeout
    'stopped') wait_for_status 3 30 2 && stop_epmd;; # wait 30x2s before timeout
    *) ctl "$@";;
esac