######## Generic Hash Table container in shared memory ########
modparam("htable", "htable", "failover=>size=16;autoexpire=120")

####### Dispatcher module  ########
loadmodule "dispatcher.so"
modparam("dispatcher", "list_file", "/etc/kazoo/kamailio/dbtext/dispatcher")
modparam("dispatcher", "flags", 2)
modparam("dispatcher", "use_default", 0)
modparam("dispatcher", "force_dst", 1)
modparam("dispatcher", "dst_avp", "$avp(ds_dst)")
modparam("dispatcher", "attrs_avp", "$avp(ds_attrs)")
modparam("dispatcher", "grp_avp", "$avp(ds_grp)")
modparam("dispatcher", "cnt_avp", "$avp(ds_cnt)")
modparam("dispatcher", "hash_pvar", "$avp(ds_grp)")
# modparam("dispatcher", "setid_pvar", "$var(setid)")
modparam("dispatcher", "ds_ping_method", "OPTIONS")
modparam("dispatcher", "ds_ping_interval", 10)
modparam("dispatcher", "ds_probing_threshhold", 3)
modparam("dispatcher", "ds_probing_mode", 1)
modparam("dispatcher", "ds_ping_reply_codes", "501,403,404,400,200")
modparam("dispatcher", "ds_ping_from", "sip:sipcheck@MY_IP_ADDRESS")
# modparam("dispatcher", "ds_ping_sock", "udp:MY_IP_ADDRESS:5060")


## Dispatcher Groups:
## 1 - Primary media servers
## 2 - Backup media servers
## 3 - Alternate media server IPs (used only for classification)
## 10 - Presence servers (if not locally handled)
## 20 - Registrar servers (if not locally handled)

####### Dispatcher Logic ########
route[DISPATCHER_CLASSIFY_SOURCE]
{
    if (ds_is_from_list(1, 3) ||
        ds_is_from_list(2, 3) ||
        ds_is_from_list(3, 3) ||
        ds_is_from_list(10, 3) ||
        ds_is_from_list(20, 3)) {
        xlog("L_INFO", "$ci|log|originated from internal sources");

        setflag(FLAG_INTERNALLY_SOURCED);
    } else {
        xlog("L_INFO", "$ci|log|originated from external sources");
    }
}

# Take the routes from dispatcher - hash over callid
# If prefered route defined, reorder the destionations
route[DISPATCHER_FIND_ROUTES]
{
    if ($sht(failover=>$ci::current) != $null) {
        $du = $sht(failover=>$ci::current);
        return;
    }

    $var(ds_group) = 1;

    #!ifndef PRESENCE-ROLE
    if (is_method("SUBSCRIBE")) {
        $var(ds_group) = 10;
    }
    #!endif

    #!ifndef REGISTRAR-ROLE
    if (is_method("REGISTER")) {
        $var(ds_group) = 20;
    }
    #!endif

    if (is_method("INVITE")) {
       if($hdr(Replaces)!= $null) {
          $var(replaced_call_id) = $(hdr(Replaces){s.select,0,;});
          xlog("L_INFO", "$ci|log|replaces call-id $var(replaced_call_id)");
          $var(amqp_payload_request) = '{"Event-Category" : "call_event" , "Event-Name" : "channel_status_req", "Call-ID" : "' + $var(replaced_call_id) + '", "Active-Only" : true }';
          $var(amqp_routing_key) = "call.status_req." + $(var(replaced_call_id){kz.encode});
          if(kazoo_query("callevt", $var(amqp_routing_key), $var(amqp_payload_request))) {
               $du = $(kzR{kz.json,Switch-URL});
               if($du != $null) {
                  xlog("L_INFO", "$ci|log|call-id $var(replaced_call_id) found redirecting call to $du, courtesy of kazoo");
                  return;
               }
          }
       }
    }

    if (!ds_select_dst("$var(ds_group)", "0") || $(avp(ds_dst)[0]) == $null) {
        # if we selected from group 1, try again in group 2
        if ($var(ds_group) == 1) {
                if (!ds_select_dst("2", "0")) {
                    xlog("L_WARN", "$ci|end|no servers avaliable in group 1 or 2");
                    sl_send_reply("480", "All servers busy");
                    exit;
                }
        } else {
            xlog("L_INFO", "$ci|end|no servers avaliable in group $var(ds_group)");
            sl_send_reply("480", "All servers busy");
            exit;
        }
    }

    $var(contact_uri) = $(ct{tobody.user}) + "@" + $(ct{tobody.host});
    $var(redirect) = @from.uri.user + "@" + @from.uri.host + "->"
        + @ruri.user + "@" + @ruri.host;
    if ($sht(redirects=>$var(redirect)) != $null) {
        $var(prefered_route) = $sht(redirects=>$var(redirect));
        xlog("L_INFO", "$ci|log|found redirect for $var(redirect)");
        if (route(DISPATCHER_REORDER_ROUTES)) {
            $avp(AVP_REDIRECT_KEY) = $var(redirect);
        }
    } else if ($sht(associations=>$var(contact_uri)) != $null) {
        $var(prefered_route) = $sht(associations=>$var(contact_uri));
        xlog("L_INFO", "$ci|log|found association for contact uri $var(contact_uri)");
        if (!route(DISPATCHER_REORDER_ROUTES)) {
            $sht(associations=>$var(association)) = $null;
        }
    }
}

route[DISPATCHER_REORDER_ROUTES]
{
    $var(i) = 0;
    $var(found) = 0;
    while($(avp(ds_dst)[$var(i)]) != $null) {
        if($(avp(ds_dst)[$var(i)]) != $var(prefered_route)) {
            $avp(tmp_ds_dst) = $(avp(ds_dst)[$var(i)]);
        } else {
            $var(found) = 1;
        }

        $var(i) = $var(i) + 1;
    }

    if (!$var(found) && $var(ds_group) == 1 && ds_select_dst("2", "0")) {
        $var(i) = 0;
        while($(avp(ds_dst)[$var(i)]) != $null) {
            if($(avp(ds_dst)[$var(i)]) == $var(prefered_route)) {
                xlog("L_INFO", "$ci|log|found associated media server in backup list");
                $var(found) = 1;
                break;
            }
            $var(i) = $var(i) + 1;
        }
    }

    if ($var(found)) {
        xlog("L_INFO", "$ci|log|re-ordering the dispatcher list to maintain association with $var(prefered_route)");

        $(avp(ds_dst)[*]) = $null;

        $var(i) = 0;
        while($(avp(tmp_ds_dst)[$var(i)]) != $null) {
            $avp(ds_dst) = $(avp(tmp_ds_dst)[$var(i)]);

            $var(i) = $var(i) + 1;
        }
        $avp(ds_dst) = $var(prefered_route);
        $du = $var(prefered_route);

        $(avp(tmp_ds_dst)[*]) = $null;
    } else {
        xlog("L_INFO", "$ci|log|associated media server $var(prefered_route) is inactive, moving to $rd");
        return -1;
    }

    return 1;
}

route[DISPATCHER_NEXT_ROUTE]
{
    $var(failover_count) = $sht(failover=>$ci::counts);

    if ($sht(failover=>$ci::counts) == $null) {
        $var(i) = 0;
        while($(avp(ds_dst)[$var(i)]) != $null) {
            $sht(failover=>$ci[$var(i)]) = $(avp(ds_dst)[$var(i)]);
            $var(i) = $var(i) + 1;
            if ($var(i) >= 3) {
                break;
            }
        }
        $sht(failover=>$ci::counts) = $var(i);
        $var(failover_count) = $var(i);
    }

    # try to find a new media server to send the call to
    if ($var(failover_count) > 1) {
        $var(failover_count) = $var(failover_count) - 1;

        $du = $sht(failover=>$ci[$var(failover_count)]);
        $sht(failover=>$ci::counts) = $var(failover_count);
        $sht(failover=>$ci::current) = $du;

        xlog("L_INFO", "$ci|log|remaining failed retry attempts: $var(failover_count)");
        xlog("L_INFO", "$ci|log|routing call to next media server $du");

        setflag(FLAG_SKIP_NAT_CORRECTION);

        # reset the final reply timer
        $avp(final_reply_timer) = 3;

        t_on_reply("INTERNAL_REPLY");

        t_on_failure("INTERNAL_FAULT");

        # relay the request to the new media server
        route(EXTERNAL_TO_INTERNAL_RELAY);

        exit();
    }
}

# vim: tabstop=4 softtabstop=4 shiftwidth=4 expandtab