// Copyright (C) 2007-2010 David Sugar, Tycho Softworks.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#include <sipwitch-config.h>
#include <sipwitch/sipwitch.h>

NAMESPACE_SIPWITCH
using namespace UCOMMON_NAMESPACE;

#ifdef  ZEROCONF_AVAHI

extern "C" {
    #include <avahi-client/client.h>
    #include <avahi-client/publish.h>
    #include <avahi-common/alternative.h>
    #include <avahi-common/thread-watch.h>
    #include <avahi-common/malloc.h>
    #include <avahi-common/error.h>
    #include <avahi-common/timeval.h>
}

class __LOCAL zeroconf : public modules::generic
{
public:
    zeroconf();

    void setClient(AvahiClientState state);
    void setGroup(AvahiEntryGroupState state);

    inline void setClient(AvahiClient *c)
        {client = c;};

    static zeroconf plugin;

private:
    void start(service *cfg);
    void stop(service *cfg);
    void reload(service *cfg);
    void publish(service *cfg);

    AvahiThreadedPoll *poller;
    AvahiClient *client;
    AvahiEntryGroup *group;
    char *name;
    const char *protocol;
    int error;
};

extern "C" {

    static void client_callback(AvahiClient *c, AvahiClientState state, void *userdata)
    {
        if(!c)
            return;

        zeroconf::plugin.setClient(c);
        zeroconf::plugin.setClient(state);
    }

    static void group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, void *userdata)
    {
        zeroconf::plugin.setGroup(state);
    }
}

zeroconf::zeroconf() :
modules::generic()
{
    protocol = "_sip._udp";
    poller = NULL;
    client = NULL;
    group = NULL;
    name = avahi_strdup("sipwitch");
    shell::log(shell::ERR, "zeroconf plugin using avahi");
}

void zeroconf::setGroup(AvahiEntryGroupState state)
{
    char *newname;

    switch(state)
    {
    case AVAHI_ENTRY_GROUP_ESTABLISHED:
        shell::log(shell::INFO, "zeroconf %s service(s) established", name);
        break;
    case AVAHI_ENTRY_GROUP_COLLISION:
        newname = avahi_alternative_service_name(name);
        shell::log(shell::NOTIFY, "zeroconf service %s renamed %s", name, newname);
        avahi_free(name);
        name = newname;
        setClient(AVAHI_CLIENT_S_RUNNING);
        break;
    case AVAHI_ENTRY_GROUP_FAILURE:
        shell::log(shell::ERR, "zeroconf service failure; error=%s",
            avahi_strerror(avahi_client_errno(client)));
        // avahi_thread_poll_quit(poller);
    default:
        break;
    }
}

void zeroconf::setClient(AvahiClientState state)
{
    int ret;
    AvahiProtocol avifamily = AVAHI_PROTO_UNSPEC;

    switch(state) {
    case AVAHI_CLIENT_S_RUNNING:
        goto add;
    case AVAHI_CLIENT_FAILURE:
failed:
        shell::log(shell::ERR, "zeroconf failure; error=%s",
            avahi_strerror(avahi_client_errno(client)));
        break;
    case AVAHI_CLIENT_S_COLLISION:
    case AVAHI_CLIENT_S_REGISTERING:
        if(group)
            avahi_entry_group_reset(group);
    default:
        break;
    }
    return;
add:
    if(!group)
        group = avahi_entry_group_new(client, group_callback, NULL);
    if(!group)
        goto failed;

    shell::log(shell::INFO, "zeroconf adding sip on port %d", sip_port);
    if(sip_domain) {
        char domain[256];
        char prefix[32];
        char range[32];
        char uuid[64];

        snprintf(domain, sizeof(domain), "domain=%s", sip_domain);
        snprintf(prefix, sizeof(prefix), "prefix=%u", sip_prefix);
        snprintf(range, sizeof(range), "range=%u", sip_range);
        snprintf(uuid, sizeof(uuid), "uuid=%s", session_uuid);
        ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, avifamily,
            (AvahiPublishFlags)0, name, protocol, NULL, NULL, sip_port,
            "type=sipwitch", domain, prefix, range, uuid, NULL);
    }
    else
        ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, avifamily,
            (AvahiPublishFlags)0, name, protocol, NULL, NULL, sip_port,
            "type=sipwitch", NULL);

    if(ret < 0)
        shell::log(shell::ERR, "zeroconf %s failed; error=%s",
            protocol, avahi_strerror(ret));

    ret = avahi_entry_group_commit(group);
    if(ret >= 0)
        return;

    shell::log(shell::ERR, "zeroconf service commit failure; error=%s",
        avahi_strerror(ret));
}

void zeroconf::stop(service *cfg)
{
    if(poller)
        avahi_threaded_poll_stop(poller);
    if(client)
        avahi_client_free(client);
    if(name)
        avahi_free(name);
//  if(poller)
//      avahi_threaded_poll_free(poller);
    client = NULL;
    poller = NULL;
    name = NULL;
}

void zeroconf::start(service *cfg)
{
    poller = avahi_threaded_poll_new();

    if(!poller) {
        shell::log(shell::ERR, "zeroconf service failed to start");
        return;
    }

    client = avahi_client_new(avahi_threaded_poll_get(poller),
        (AvahiClientFlags)0, client_callback, NULL, &error);

    shell::log(shell::INFO, "zeroconf service started");
    avahi_threaded_poll_start(poller);
}

void zeroconf::reload(service *cfg)
{
    if(sip_protocol == IPPROTO_TCP)
        protocol = "_sip._tcp";
}

void zeroconf::publish(service *cfg)
{
    assert(cfg != NULL);

    char domain[256];
    char prefix[32];
    char range[32];
    char uuid[64];

    static bool started = false;
    AvahiProtocol avifamily = AVAHI_PROTO_UNSPEC;
    int ret = 0;

    if(started && group && sip_domain) {
        snprintf(domain, sizeof(domain), "domain=%s", sip_domain);
        snprintf(prefix, sizeof(prefix), "prefix=%u", sip_prefix);
        snprintf(range, sizeof(range), "range=%u", sip_range);
        snprintf(uuid, sizeof(uuid), "uuid=%s", session_uuid);
        ret = avahi_entry_group_update_service_txt(group, AVAHI_IF_UNSPEC, avifamily,
            (AvahiPublishFlags)0, name, protocol, NULL,
            "type=sipwitch", domain, prefix, range, uuid, NULL);
    }
    else if(started && group) {
        ret = avahi_entry_group_update_service_txt(group, AVAHI_IF_UNSPEC, avifamily,
            (AvahiPublishFlags)0, name, protocol, NULL,
            "type=sipwitch", NULL);
    }

    if(ret < 0)
        shell::log(shell::ERR, "zeroconf %s failed; error=%s",
            protocol, avahi_strerror(ret));

    started = true;
}

#else

class __LOCAL zeroconf : modules::generic
{
public:
    static zeroconf plugin;

    zeroconf();
};

zeroconf::zeroconf() :
modules::generic()
{
    shell::log(shell::ERR, "zeroconf plugin could not be built");
}

#endif

zeroconf zeroconf::plugin;

END_NAMESPACE