#!/bin/bash

# Add the current ejabberd node in a cluster

# copyright (c) 2010 ProcessOne
#
# This script is proprietary software and cannot be published or redistribute.

# Return Code:
#  0 : groovy baby
# 11 : erl not found
# 12 : erlc not found
# 20 : database dir doesn't exist
# 21 : database dir not writable
# 21 : database dir variable not set
# 30 : network issue
# 31 : node names incompatibility

function error
{
    echo "Error: $1" >&2
    exit $2
}

echo "--------------------------------------------------------------------"
echo ""
echo "ejabberd cluster configuration"
echo ""
echo "This ejabberd node will be configured for use in an ejabberd cluster."
echo "IMPORTANT: all local data from the database will be lost, and"
echo "cluster database will be initialized. All data from the master"
echo "node will be replicated to this one."
echo ""
echo "--------------------------------------------------------------------"
echo "Press any key to continue, or Ctrl+C to stop now"
read foo
echo ""

echo "Make sure you have a running remote master ejabberd node"
echo "Before continuing, you must copy the ~/.erlang.cookie file from"
echo "remote master node and check ejabberd.cfg compatibility."
echo "e.g. hosts definition must match on all nodes"
echo ""
echo "The remote master node name is defined as ERLANG_NODE into"
echo "ejabberdctl.cfg on that remote node."
echo ""
echo -n "Remote master node name: "
read REMOTE
echo ""

cont=Y
ping -q -c 1 ${REMOTE#*@} 2>/dev/null >/dev/null
[ $? -eq 0 ] || {
    echo "Cannot ping ${REMOTE#*@}. Are you sure network setup is correct ?"
    echo -n "Should we continue anyway ? (Y/n) "
    read cont
}
cont=`echo $cont | tr a-z A-Z`
[ "$cont" == "Y" ] || error "Check your network configuration (dns, firewall, etc...)" 30

HERE=`which "$0"`
BASE=`dirname $HERE`/..
ROOTDIR=`cd $BASE; pwd`
. $ROOTDIR/bin/ejabberdctl stop 2>/dev/null >/dev/null
NAME=-name
[ "$ERLANG_NODE" = "${ERLANG_NODE%.*}" ] && NAME=-sname
PA=/tmp/clustersetup_$$
CLUSTERSETUP=clustersetup
CLUSTERSETUP_ERL=$PA/$CLUSTERSETUP.erl

REMOTENAME=-name
[ "$REMOTE" = "${REMOTE%.*}" ] && REMOTENAME=-sname
[ "$REMOTENAME" = "$NAME" ] || {
    echo "IMPORTANT!: node names are incompatible"
    echo "Remote node name is $REMOTE"
    echo "Local node name is $ERLANG_NODE"
    echo ""
    echo "Both node names must be short or fqdn names."
    echo "Using short and fqdn names is impossible."
    echo ""
    error "incompatible node names" 31
}

set -o errexit
set -o nounset

echo "Using commands:"
which erl  || error "can't find erl"  11
which erlc || error "can't find erlc" 12
echo ""

[ -d $EJABBERD_DB ] && rm -Rf $EJABBERD_DB
mkdir $EJABBERD_DB || error "$EJABBERD_DB cannot be created" 20
[ -w $EJABBERD_DB ] || error "$EJABBERD_DB directory is not writable" 21

cd $ROOTDIR
mkdir -p $PA
cat <<EOF > $CLUSTERSETUP_ERL
-module($CLUSTERSETUP).

-export([start/0]).

set_table_copy(Table, _Node, {badrpc, Reason}) ->
    io:format("Error: cannot get storage type for table ~p on node $REMOTE:~n ~p~n",[Table, Reason]);
set_table_copy(Table, Node, Type) ->
    io:format("setting table ~p to mode ~p~n",[Table, Type]),
    case mnesia:add_table_copy(Table, Node, Type) of
    {aborted, _} ->
        mnesia:change_table_copy_type(Table, Node, Type);
    _ ->
        ok
    end.

set_tables({badrpc, Reason}) ->
    io:format("ERROR: cannot get tables list on $REMOTE : ~p~n",[Reason]);
set_tables([]) ->
    ok;
set_tables([schema | Tables]) ->
    set_tables(Tables);
set_tables([s2s | Tables]) ->
    set_tables(Tables);
set_tables([session | Tables]) ->
    set_tables(Tables);
set_tables([Table | Tables]) ->
    set_table_copy(Table, node(),
                   rpc:call('$REMOTE', mnesia, table_info, [Table, storage_type])),
    set_tables(Tables).

start() ->
    io:format("~n",[]),
    set_table_copy(schema, node(), disc_copies),
    set_tables(rpc:call('$REMOTE', mnesia, system_info, [tables])),
    halt(0).
EOF
erlc -o $PA $CLUSTERSETUP_ERL
erl $NAME $ERLANG_NODE -pa $PA $KERNEL_OPTS -mnesia extra_db_nodes "['$REMOTE']" dir "\"$EJABBERD_DB\"" -s mnesia -s $CLUSTERSETUP start
rm -Rf $PA

echo "End."
echo "Check that there is no error in the above messages."