/**
 * GMyth Library
 *
 * @file gmyth/gmyth_upnp.c
 * 
 * @brief <p> GMythUPnP allows that a MythTV frontend discovers a 
 * MythTV backend, using the UPnP architecture.
 *
 * Copyright (C) 2006 INdT - Instituto Nokia de Tecnologia.
 * @author Rosfran Lins Borges <rosfran.borges@indt.org.br>
 * @authon Renato Araujo Oliveira Filho <renato.filho@indt.org.br>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "gmyth_upnp.h"

#include <gmyth/gmyth.h>
#include <upnp/upnp.h>
#include <string.h>


#define UPNP_SEARCH_TIMEOUT 5
#define UPNP_SERVICE_FILTER  "urn:schemas-mythtv-org:service:MythTv:1"
#define SERVER_ID           "MythTV AV Media Server"

typedef struct _GMythUPnPPrivate GMythUPnPPrivate;
typedef struct _GMythUPnPIdleData GMythUPnPIdleData;

#define GMYTH_UPNP_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GMYTH_UPNP_TYPE, GMythUPnPPrivate))

enum
{
    DEVICE_FOUND,
    DEVICE_LOST,
    LAST_SIGNAL
};

struct _GMythUPnPIdleData
{
    GMythUPnP *parent;
    GMythBackendInfo *server;
};

struct _GMythUPnPPrivate {
    GHashTable     *servers;
    GMythUPnPDeviceStatus last_status;
    gboolean        upnp_dev_found;
    gchar          *udn;
    GMutex         *mutex;
    gint            idle_count;

    /* upnp */
    UpnpClient_Handle client_id;
};

static void     gmyth_upnp_class_init   (GMythUPnPClass* klass);
static void     gmyth_upnp_init         (GMythUPnP* object);
static void     gmyth_upnp_dispose      (GObject* object);
static void     gmyth_upnp_finalize     (GObject* object);
static GObject* gmyth_upnp_constructor  (GType type,
                                         guint n_construct_params,
                                         GObjectConstructParam *construct_params);


static int      _upnp_event_handler     (Upnp_EventType e_type,
                                         void* e,
                                         void* data);


static int signals[LAST_SIGNAL] = {0};

static GMythUPnP *singleton = NULL;

G_DEFINE_TYPE(GMythUPnP, gmyth_upnp, G_TYPE_OBJECT);

static void
gmyth_upnp_class_init(GMythUPnPClass * klass)
{
    GObjectClass   *gobject_class;
    GMythUPnPClass *gupnp_class;

    gobject_class = (GObjectClass *) klass;
    gupnp_class = (GMythUPnPClass *) gobject_class;

    gobject_class->dispose = gmyth_upnp_dispose;
    gobject_class->finalize = gmyth_upnp_finalize;
    gobject_class->constructor = gmyth_upnp_constructor;

    g_type_class_add_private (gobject_class, sizeof(GMythUPnPPrivate));



    signals[DEVICE_FOUND] = g_signal_new("device-found",
                                         G_TYPE_FROM_CLASS(gupnp_class),
                                         G_SIGNAL_RUN_LAST,
                                         0, NULL, NULL,
                                         g_cclosure_marshal_VOID__OBJECT,
                                         G_TYPE_NONE, 1,
                                         GMYTH_BACKEND_INFO_TYPE);

    signals[DEVICE_LOST] = g_signal_new("device-lost",
                                         G_TYPE_FROM_CLASS(gupnp_class),
                                         G_SIGNAL_RUN_LAST,
                                         0, NULL, NULL,
                                         g_cclosure_marshal_VOID__OBJECT,
                                         G_TYPE_NONE, 1,
                                         GMYTH_BACKEND_INFO_TYPE);

}

static void
gmyth_upnp_init(GMythUPnP* self)
{
    gint ret;
    GMythUPnPPrivate *priv;

    priv = GMYTH_UPNP_GET_PRIVATE (self);

    priv->mutex = g_mutex_new ();
    priv->servers = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_object_unref);

    /* initalize upnp client */
    ret = UpnpInit (NULL, 0);
    if (ret != UPNP_E_SUCCESS)
        g_warning ("Fail to inilialize upnp SDK: %d", ret);
    else
    {
        ret = UpnpRegisterClient (_upnp_event_handler,
                                  &priv->client_id, &priv->client_id);

        if (ret != UPNP_E_SUCCESS)
            g_warning ("Fail to start upnp client: %d", ret);
    }
}

static GObject*
gmyth_upnp_constructor (GType type,
                        guint n_construct_params,
                        GObjectConstructParam *construct_params)
{
    GObject *object;

    if (!singleton)
    {
        object = G_OBJECT_CLASS (gmyth_upnp_parent_class)->constructor (type,
                                                             n_construct_params,
                                                             construct_params);

        singleton = GMYTH_UPNP (object);
    }
    else
        object = g_object_ref (G_OBJECT (singleton));

    return object;
}

static void
gmyth_upnp_dispose(GObject * object)
{
    /* finalize upnp client */
    UpnpFinish ();
    G_OBJECT_CLASS(gmyth_upnp_parent_class)->dispose(object);
}

static void
gmyth_upnp_finalize(GObject * object)
{
    G_OBJECT_CLASS(gmyth_upnp_parent_class)->finalize(object);
    singleton = NULL;
}


GMythUPnP*
gmyth_upnp_get_instance (void)
{
    return GMYTH_UPNP(g_object_new(GMYTH_UPNP_TYPE, NULL));
}


void
gmyth_upnp_search (GMythUPnP *self)
{
    int ret;
    GMythUPnPPrivate *priv;

    priv = GMYTH_UPNP_GET_PRIVATE (self);

    ret = UpnpSearchAsync (priv->client_id,
                           UPNP_SEARCH_TIMEOUT,
                           UPNP_SERVICE_FILTER,
                           NULL);

    if (ret != UPNP_E_SUCCESS)
        g_warning ("Fail to start upnp listener: %d", ret);
}

static void
_fill_servers_cb (gpointer key,
                  gpointer value,
                  gpointer user_data)
{
    GList **lst;

    lst = (GList **) user_data;

    *lst = g_list_append (*lst, g_object_ref (value));
}

GList*
gmyth_upnp_get_devices (GMythUPnP *self)
{
    GMythUPnPPrivate *priv;
    GList *lst;

    priv = GMYTH_UPNP_GET_PRIVATE (self);
    lst = NULL;
    g_hash_table_foreach (priv->servers, (GHFunc) _fill_servers_cb, &lst);

    return lst;
}

static gboolean
_idle_emit_device_found_signal (gpointer data)
{
    GMythUPnPPrivate *priv;
    GMythUPnPIdleData *idle_data;

    idle_data = (GMythUPnPIdleData *) data;
    priv = GMYTH_UPNP_GET_PRIVATE (idle_data->parent);

    g_signal_emit (idle_data->parent, signals[DEVICE_FOUND], 0, idle_data->server);

    g_object_unref (idle_data->server);
    g_free (idle_data);
    priv->idle_count--;

    return FALSE;
}

static gboolean
_idle_emit_device_lost_signal (gpointer data)
{
    GMythUPnPPrivate *priv;
    GMythUPnPIdleData *idle_data;

    idle_data = (GMythUPnPIdleData *) data;
    priv = GMYTH_UPNP_GET_PRIVATE (idle_data->parent);

    g_signal_emit (idle_data->parent, signals[DEVICE_LOST], 0, idle_data->server);

    g_object_unref (idle_data->server);
    g_free (idle_data);
    priv->idle_count--;

    return FALSE;
}

static char*
_xml_get_first_document_item (IXML_Document * doc,
                              const gchar *item )
{
    IXML_NodeList *node_list = NULL;
    IXML_Node *text_node = NULL;
    IXML_Node *tmp_node = NULL;

    gchar *ret = NULL;

    node_list = ixmlDocument_getElementsByTagName (doc,
                                                  (char *) item);

    if (node_list)
    {
        if ((tmp_node = ixmlNodeList_item (node_list, 0))) 
        {
            text_node = ixmlNode_getFirstChild (tmp_node);

            ret = strdup (ixmlNode_getNodeValue (text_node));
        }
    }

    if (node_list)
        ixmlNodeList_free (node_list);

    return ret;
}


static void
_append_mythtv_server_from_loation (GMythUPnP *self,
                                    const gchar *uuid,
                                    const gchar *location)
{
    GMythUPnPPrivate *priv;
    gchar *base_url;
    gchar *end;

    priv = GMYTH_UPNP_GET_PRIVATE (self);

    base_url = g_strdup (location);
    end = g_strrstr (base_url, "/");
    if (end)
    {
        gint ret;
        IXML_Document *desc_doc;
        gchar *info_url;

        end[0] = '\0';
        info_url = g_strconcat (base_url,
                                "Myth/GetConnectionInfo",
                                NULL);
        g_free (base_url);
        desc_doc = NULL;
        ret = UpnpDownloadXmlDoc (info_url, &desc_doc);
        if (ret != UPNP_E_SUCCESS)
        {
            g_warning ("Error obtaining device desc: %d", ret);
        }
        else
        {
            GMythBackendInfo *info;
            GMythUPnPIdleData *idle_data;

            info = gmyth_backend_info_new_full (
                _xml_get_first_document_item (desc_doc, "Host"),
                _xml_get_first_document_item (desc_doc, "UserName"),
                _xml_get_first_document_item (desc_doc, "Password"),
                _xml_get_first_document_item (desc_doc, "Name"),
                // Current mythtv version not export port number
                6543);

            if (desc_doc)
                ixmlDocument_free (desc_doc);

            g_mutex_lock (priv->mutex);
            g_hash_table_insert (priv->servers, 
                                 g_strdup (uuid),
                                 g_object_ref (info));
            g_mutex_unlock (priv->mutex);
            g_free (info_url);

            idle_data = g_new0 (GMythUPnPIdleData, 1);
            idle_data->parent = self;
            idle_data->server = g_object_ref (info);

            priv->idle_count++;
            g_idle_add (_idle_emit_device_found_signal, idle_data);
        }
    }
}

static void
_remove_mythtv_server (GMythUPnP *self,
                       const gchar *uuid)
{
    GMythUPnPPrivate *priv;
    GMythBackendInfo *info;

    priv = GMYTH_UPNP_GET_PRIVATE (self);

    g_mutex_lock (priv->mutex);
    info = g_hash_table_lookup (priv->servers, uuid);
    if (info)
    {
        GMythUPnPIdleData *idle_data;

        idle_data = g_new0 (GMythUPnPIdleData, 1);
        idle_data->parent = self;
        idle_data->server = g_object_ref (info);

        g_hash_table_remove (priv->servers, uuid);

        priv->idle_count++;
        g_idle_add (_idle_emit_device_lost_signal, idle_data);
    }
    g_mutex_unlock (priv->mutex);

}

static GMythBackendInfo*
_find_service_by_uuid (GMythUPnP *self,
                      const gchar *uuid)
{
    GMythUPnPPrivate *priv;
    GMythBackendInfo *info;

    priv = GMYTH_UPNP_GET_PRIVATE (self);
    info = NULL;

    g_mutex_lock (priv->mutex);
    info = g_hash_table_lookup (priv->servers, uuid);
    g_mutex_unlock (priv->mutex);

    return info;
}

static int
_upnp_event_handler (Upnp_EventType e_type,
                     void* e,
                     void* data)
{
    g_return_val_if_fail (singleton != NULL, 0);

    switch (e_type)
    {
        case UPNP_DISCOVERY_ADVERTISEMENT_ALIVE:
        case UPNP_DISCOVERY_SEARCH_RESULT:
        {
            struct Upnp_Discovery *d_event;

            d_event = (struct Upnp_Discovery *) e;

            if (strcmp (d_event->ServiceType, UPNP_SERVICE_FILTER) != 0)
            {
                g_warning ("invalid device : %s", d_event->DeviceId);
                break;
            }


            if (d_event->ErrCode != UPNP_E_SUCCESS)
            {
                g_warning ("Error in Discovery: %d", d_event->ErrCode);
                break;
            }

            if (_find_service_by_uuid (GMYTH_UPNP (singleton), d_event->DeviceId) == NULL)
                _append_mythtv_server_from_loation (singleton,
                                                    d_event->DeviceId,
                                                    d_event->Location);


            break;
        }
        case UPNP_DISCOVERY_ADVERTISEMENT_BYEBYE:
        {
            GMythUPnPPrivate *priv;
            struct Upnp_Discovery *d_event;

            d_event = (struct Upnp_Discovery *) e;
            if (d_event->ErrCode != UPNP_E_SUCCESS)
            {
                g_warning ("Error in Discovery: %d", d_event->ErrCode);
                break;
            }

            priv = GMYTH_UPNP_GET_PRIVATE (singleton);
            _remove_mythtv_server (singleton,
                                   d_event->DeviceId);

            break;

        }
        default:
            break;
    }

    return 0;
}