path: root/calendar/pcs/cal-factory.c

/* Evolution calendar factory
 *
 * Copyright (C) 2000-2003 Ximian, Inc.
 *
 * Authors: 
 *   Federico Mena-Quintero <federico@ximian.com>
 *   JP Rosevear <jpr@ximian.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */

#include <bonobo-activation/bonobo-activation.h>
#include <bonobo/bonobo-exception.h>
#include <bonobo/bonobo-main.h>
#include "e-util/e-url.h"
#include "evolution-calendar.h"
#include "cal-backend.h"
#include "cal.h"
#include "cal-factory.h"

#define PARENT_TYPE                BONOBO_TYPE_OBJECT
#define DEFAULT_CAL_FACTORY_OAF_ID "OAFIID:GNOME_Evolution_Wombat_CalendarFactory"

static BonoboObjectClass *parent_class;

/* Private part of the CalFactory structure */
struct _CalFactoryPrivate {
    /* Hash table from URI method strings to GType * for backend class types */
    GHashTable *methods;

    /* Hash table from GnomeVFSURI structures to CalBackend objects */
    GHashTable *backends;

    /* OAFIID of the factory */
    char *iid;

    /* Whether we have been registered with OAF yet */
    guint registered : 1;
};

/* Signal IDs */
enum SIGNALS {
    LAST_CALENDAR_GONE,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL];

/* Opening calendars */
static icalcomponent_kind
calobjtype_to_icalkind (const GNOME_Evolution_Calendar_CalObjType type)
{
    switch (type){
    case GNOME_Evolution_Calendar_TYPE_EVENT:
        return ICAL_VEVENT_COMPONENT;
    case GNOME_Evolution_Calendar_TYPE_TODO:
        return ICAL_VTODO_COMPONENT;
    case GNOME_Evolution_Calendar_TYPE_JOURNAL:
        return ICAL_VJOURNAL_COMPONENT;
    }
    
    return ICAL_NO_COMPONENT;
}

static GType
get_backend_type (GHashTable *methods, const char *method, icalcomponent_kind kind)
{
    GHashTable *kinds;
    GType type;
    
    kinds = g_hash_table_lookup (methods, method);
    if (!kinds)
        return 0;

    type = GPOINTER_TO_INT (g_hash_table_lookup (kinds, GINT_TO_POINTER (kind)));

    return type;
}

/* Looks up a calendar backend in a factory's hash table of uri->cal.  If
 * *non-NULL, orig_uri_return will be set to point to the original key in the
 * *hash table.
 */
static CalBackend *
lookup_backend (CalFactory *factory, const char *uristr)
{
    CalFactoryPrivate *priv;
    EUri *uri;
    CalBackend *backend;
    char *tmp;

    priv = factory->priv;

    uri = e_uri_new (uristr);
    if (!uri)
        return NULL;

    tmp = e_uri_to_string (uri, FALSE);
    backend = g_hash_table_lookup (priv->backends, tmp);
    g_free (tmp);
    e_uri_free (uri);

    return backend;
}

/* Callback used when a backend loses its last connected client */
static void
backend_last_client_gone_cb (CalBackend *backend, gpointer data)
{
    CalFactory *factory;
    CalFactoryPrivate *priv;
    CalBackend *ret_backend;
    const char *uristr;

    fprintf (stderr, "backend_last_client_gone_cb() called!\n");

    factory = CAL_FACTORY (data);
    priv = factory->priv;

    /* Remove the backend from the hash table */

    uristr = cal_backend_get_uri (backend);
    g_assert (uristr != NULL);

    ret_backend = lookup_backend (factory, uristr);
    g_assert (ret_backend != NULL);
    g_assert (ret_backend == backend);

    g_hash_table_remove (priv->backends, uristr);

    /* Notify upstream if there are no more backends */

    if (g_hash_table_size (priv->backends) == 0)
        g_signal_emit (G_OBJECT (factory), signals[LAST_CALENDAR_GONE], 0);
}



static GNOME_Evolution_Calendar_Cal
impl_CalFactory_getCal (PortableServer_Servant servant,
            const CORBA_char *str_uri,
            const GNOME_Evolution_Calendar_CalObjType type,
            const GNOME_Evolution_Calendar_Listener listener,
            CORBA_Environment *ev)
{
    CalFactory *factory;
    CalFactoryPrivate *priv;
    Cal *cal = CORBA_OBJECT_NIL;
    CalBackend *backend;
    CORBA_Environment ev2;
    GNOME_Evolution_Calendar_Listener listener_copy;
    GType backend_type;
    EUri *uri;
    char *uri_string;
    
    factory = CAL_FACTORY (bonobo_object_from_servant (servant));
    priv = factory->priv;

    /* Parse the uri */
    uri = e_uri_new (str_uri);
    if (!uri) {
        bonobo_exception_set (ev, ex_GNOME_Evolution_Calendar_CalFactory_InvalidURI);

        return CORBA_OBJECT_NIL;
    }
    uri_string = e_uri_to_string (uri, FALSE);  

    /* Find the associated backend type (if any) */
    backend_type = get_backend_type (priv->methods, uri->protocol, calobjtype_to_icalkind (type));
    if (!backend_type) {
        /* FIXME Distinguish between method and kind failures? */
        bonobo_exception_set (ev, ex_GNOME_Evolution_Calendar_CalFactory_UnsupportedMethod);
        goto cleanup;
    }
        
    /* Duplicate the listener object */
    CORBA_exception_init (&ev2);
    listener_copy = CORBA_Object_duplicate (listener, &ev2);

    if (BONOBO_EX (&ev2)) {
        g_warning (G_STRLOC ": could not duplicate the listener");
        bonobo_exception_set (ev, ex_GNOME_Evolution_Calendar_CalFactory_NilListener);
        CORBA_exception_free (&ev2);
        goto cleanup;
    }
    CORBA_exception_free (&ev2);

    /* Look for an existing backend */
    backend = lookup_backend (factory, uri_string);
    if (!backend) {
        /* There was no existing backend, create a new one */
        backend = g_object_new (backend_type, "uri", uri_string, "kind", calobjtype_to_icalkind (type), NULL);
        if (!backend) {
            g_warning (G_STRLOC ": could not instantiate backend");
            bonobo_exception_set (ev, ex_GNOME_Evolution_Calendar_CalFactory_UnsupportedMethod);
            goto cleanup;
        }

        /* Track the backend */
        g_hash_table_insert (priv->backends, g_strdup (uri_string), backend);

        g_signal_connect (G_OBJECT (backend), "last_client_gone",
                  G_CALLBACK (backend_last_client_gone_cb),
                  factory);
    }
    
    /* Create the corba calendar */
    cal = cal_new (backend, uri_string, listener);
    if (!cal) {
        g_warning (G_STRLOC ": could not create the corba calendar");
        bonobo_exception_set (ev, ex_GNOME_Evolution_Calendar_CalFactory_UnsupportedMethod);
        goto cleanup;
    }

    /* Let the backend know about its clients corba clients */
    cal_backend_add_client (backend, cal);
    
 cleanup:
    e_uri_free (uri);
    g_free (uri_string);

    return CORBA_Object_duplicate (BONOBO_OBJREF (cal), ev);
}



/**
 * cal_factory_new:
 * @void:
 *
 * Creates a new #CalFactory object.
 *
 * Return value: A newly-created #CalFactory, or NULL if its corresponding CORBA
 * object could not be created.
 **/
CalFactory *
cal_factory_new (void)
{
    CalFactory *factory;

    factory = g_object_new (CAL_FACTORY_TYPE, 
                "poa", bonobo_poa_get_threaded (ORBIT_THREAD_HINT_PER_REQUEST, NULL), 
                NULL);

    return factory;
}

/* Destroy handler for the calendar */
static void
cal_factory_finalize (GObject *object)
{
    CalFactory *factory;
    CalFactoryPrivate *priv;

    g_return_if_fail (object != NULL);
    g_return_if_fail (IS_CAL_FACTORY (object));

    factory = CAL_FACTORY (object);
    priv = factory->priv;

    g_hash_table_destroy (priv->methods);
    priv->methods = NULL;

    /* Should we assert that there are no more backends? */
    g_hash_table_destroy (priv->backends);
    priv->backends = NULL;

    if (priv->registered) {
        bonobo_activation_active_server_unregister (priv->iid, BONOBO_OBJREF (factory));
        priv->registered = FALSE;
    }
    g_free (priv->iid);

    g_free (priv);
    factory->priv = NULL;

    if (G_OBJECT_CLASS (parent_class)->finalize)
        (* G_OBJECT_CLASS (parent_class)->finalize) (object);
}

/* Class initialization function for the calendar factory */
static void
cal_factory_class_init (CalFactoryClass *klass)
{
    GObjectClass *object_class = (GObjectClass *) klass;
    POA_GNOME_Evolution_Calendar_CalFactory__epv *epv = &klass->epv;

    parent_class = g_type_class_peek_parent (klass);

    signals[LAST_CALENDAR_GONE] =
        g_signal_new ("last_calendar_gone",
                  G_TYPE_FROM_CLASS (klass),
                  G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (CalFactoryClass, last_calendar_gone),
                  NULL, NULL,
                  g_cclosure_marshal_VOID__VOID,
                  G_TYPE_NONE, 0);

    /* Class method overrides */
    object_class->finalize = cal_factory_finalize;

    /* Epv methods */
    epv->getCal = impl_CalFactory_getCal;
}

/* Object initialization function for the calendar factory */
static void
cal_factory_init (CalFactory *factory, CalFactoryClass *klass)
{
    CalFactoryPrivate *priv;

    priv = g_new0 (CalFactoryPrivate, 1);
    factory->priv = priv;

    priv->methods = g_hash_table_new_full (g_str_hash, g_str_equal, 
                           (GDestroyNotify) g_free, (GDestroyNotify) g_hash_table_destroy);
    priv->backends = g_hash_table_new_full (g_str_hash, g_str_equal, 
                        (GDestroyNotify) g_free, (GDestroyNotify) g_object_unref);
    priv->registered = FALSE;
}

BONOBO_TYPE_FUNC_FULL (CalFactory,
               GNOME_Evolution_Calendar_CalFactory,
               PARENT_TYPE,
               cal_factory);

/**
 * cal_factory_register_storage:
 * @factory: A calendar factory.
 * @iid: OAFIID for the factory to be registered.
 * 
 * Registers a calendar factory with the OAF object activation daemon.  This
 * function must be called before any clients can activate the factory.
 * 
 * Return value: TRUE on success, FALSE otherwise.
 **/
gboolean
cal_factory_register_storage (CalFactory *factory, const char *iid)
{
    CalFactoryPrivate *priv;
    Bonobo_RegistrationResult result;
    char *tmp_iid;

    g_return_val_if_fail (factory != NULL, FALSE);
    g_return_val_if_fail (IS_CAL_FACTORY (factory), FALSE);

    priv = factory->priv;

    g_return_val_if_fail (!priv->registered, FALSE);

    /* if iid is NULL, use the default factory OAFIID */
    if (iid)
        tmp_iid = g_strdup (iid);
    else
        tmp_iid = g_strdup (DEFAULT_CAL_FACTORY_OAF_ID);

    result = bonobo_activation_active_server_register (tmp_iid, BONOBO_OBJREF (factory));

    switch (result) {
    case Bonobo_ACTIVATION_REG_SUCCESS:
        priv->registered = TRUE;
        priv->iid = tmp_iid;
        return TRUE;

    case Bonobo_ACTIVATION_REG_NOT_LISTED:
        g_warning (G_STRLOC ": cannot register the calendar factory (not listed)");
        break;

    case Bonobo_ACTIVATION_REG_ALREADY_ACTIVE:
        g_warning (G_STRLOC ": cannot register the calendar factory (already active)");
        break;

    case Bonobo_ACTIVATION_REG_ERROR:
    default:
        g_warning (G_STRLOC ": cannot register the calendar factory (generic error)");
        break;
    }

    g_free (tmp_iid);

    return FALSE;
}

/**
 * cal_factory_register_method:
 * @factory: A calendar factory.
 * @method: Method for the URI, i.e. "http", "file", etc.
 * @backend_type: Class type of the backend to create for this @method.
 * 
 * Registers the type of a #CalBackend subclass that will be used to handle URIs
 * with a particular method.  When the factory is asked to open a particular
 * URI, it will look in its list of registered methods and create a backend of
 * the appropriate type.
 **/
void
cal_factory_register_method (CalFactory *factory, const char *method, icalcomponent_kind kind, GType backend_type)
{
    CalFactoryPrivate *priv;
    char *method_str;
    GHashTable *kinds;
    GType type;
    
    g_return_if_fail (factory != NULL);
    g_return_if_fail (IS_CAL_FACTORY (factory));
    g_return_if_fail (method != NULL);
    g_return_if_fail (backend_type != 0);
    g_return_if_fail (g_type_is_a (backend_type, CAL_BACKEND_TYPE));

    priv = factory->priv;

    method_str = g_ascii_strdown (method, -1);

    kinds = g_hash_table_lookup (priv->methods, method_str);
    if (kinds) {
        type = GPOINTER_TO_INT (g_hash_table_lookup (kinds, GINT_TO_POINTER (kind)));
        if (type) {
            g_warning (G_STRLOC ": method `%s' already registered", method_str);
            g_free (method_str);

            return;
        }       
    } else {
        kinds = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, NULL);
        g_hash_table_insert (priv->methods, method_str, kinds);
    }   
    
    g_hash_table_insert (kinds, GINT_TO_POINTER (kind), GINT_TO_POINTER (backend_type));
}

/**
 * cal_factory_get_n_backends
 * @factory: A calendar factory.
 *
 * Get the number of backends currently active in the given factory.
 *
 * Returns: the number of backends.
 */
int
cal_factory_get_n_backends (CalFactory *factory)
{
    CalFactoryPrivate *priv;

    g_return_val_if_fail (IS_CAL_FACTORY (factory), 0);

    priv = factory->priv;
    return g_hash_table_size (priv->backends);
}

/* Frees a uri/backend pair from the backends hash table */
static void
dump_backend (gpointer key, gpointer value, gpointer data)
{
    char *uri;
    CalBackend *backend;

    uri = key;
    backend = value;

    g_message ("  %s: %p", uri, backend);
}

void
cal_factory_dump_active_backends   (CalFactory *factory)
{
    CalFactoryPrivate *priv;

    g_message ("Active PCS backends");

    priv = factory->priv;
    g_hash_table_foreach (priv->backends, dump_backend, NULL);
}