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

/* Evolution calendar factory
 *
 * Copyright (C) 2000 Ximian, Inc.
 * Copyright (C) 2000 Ximian, Inc.
 *
 * Author: Federico Mena-Quintero <federico@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 <config.h>
#include <ctype.h>
#include <stdio.h>
#include <bonobo-activation/bonobo-activation.h>
#include "e-util/e-url.h"
#include "evolution-calendar.h"
#include "cal.h"
#include "cal-backend.h"
#include "cal-factory.h"
#include "job.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;
};

typedef struct 
{
    CalFactory *factory;    
    GNOME_Evolution_Calendar_CalMode mode;  
    GNOME_Evolution_Calendar_StringSeq *list;
} CalFactoryUriData;

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

static guint signals[LAST_SIGNAL];

/* Frees a method/GType * pair from the methods hash table */
static void
free_method (gpointer key, gpointer value, gpointer data)
{
    char *method;
    GType *type;

    method = key;
    type = value;

    g_free (method);
    g_free (type);
}

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

    uri = key;
    backend = value;

    g_free (uri);
    g_object_unref (backend);
}

/* Opening calendars */

/* 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, char **orig_uri_return)
{
    CalFactoryPrivate *priv;
    EUri *uri;
    char *tmp;
    gboolean found;
    gpointer orig_key;
    gpointer data;

    priv = factory->priv;

    uri = e_uri_new (uristr);
    if (!uri) {
        if (orig_uri_return)
            *orig_uri_return = NULL;

        return NULL;
    }

    tmp = e_uri_to_string (uri, FALSE);
    found = g_hash_table_lookup_extended (priv->backends, tmp, &orig_key, &data);
    g_free (tmp);
    e_uri_free (uri);

    if (found) {
        if (orig_uri_return)
            *orig_uri_return = orig_key;

        return CAL_BACKEND (data);
    } else {
        if (orig_uri_return)
            *orig_uri_return = NULL;

        return NULL;
    }
}

/* 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;
    char *orig_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, &orig_uristr);
    g_assert (ret_backend != NULL);
    g_assert (ret_backend == backend);

    g_hash_table_remove (priv->backends, orig_uristr);
    g_free (orig_uristr);

    g_object_unref (backend);

    /* 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);
}

/* Adds a backend to the calendar factory's hash table */
static void
add_backend (CalFactory *factory, const char *uristr, CalBackend *backend)
{
    CalFactoryPrivate *priv;
    EUri *uri;
    char *tmp;

    priv = factory->priv;

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

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

    g_signal_connect (G_OBJECT (backend), "last_client_gone",
              G_CALLBACK (backend_last_client_gone_cb),
              factory);
}

/* Tries to launch a backend for the method of the specified URI.  If there is
 * no such method registered in the factory, it sends the listener the
 * MethodNotSupported error code.
 */
static CalBackend *
launch_backend_for_uri (CalFactory *factory,
            const char *uristr,
            GNOME_Evolution_Calendar_Listener listener)
{
    CalFactoryPrivate *priv;
    const char *method;
    GType *type;
    CalBackend *backend;
    EUri *uri;

    priv = factory->priv;

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

    method = uri->protocol;
    type = g_hash_table_lookup (priv->methods, method);
    e_uri_free (uri);

    if (!type) {
        CORBA_Environment ev;

        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_METHOD_NOT_SUPPORTED,
            CORBA_OBJECT_NIL,
            &ev);

        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("launch_backend_for_uri(): could not notify the listener");

        CORBA_exception_free (&ev);
        return NULL;
    }

    backend = g_object_new (*type, NULL);
    if (!backend)
        g_message ("launch_backend_for_uri(): could not launch the backend");

    return backend;
}

/* Opens a calendar backend and puts it in the factory's backend hash table */
static CalBackend *
open_backend (CalFactory *factory, const char *uristr, gboolean only_if_exists,
          GNOME_Evolution_Calendar_Listener listener)
{
    CalFactoryPrivate *priv;
    CalBackend *backend;
    CalBackendOpenStatus status;
    CORBA_Environment ev;

    priv = factory->priv;

    backend = launch_backend_for_uri (factory, uristr, listener);
    if (!backend)
        return NULL;

    status = cal_backend_open (backend, uristr, only_if_exists);

    switch (status) {
    case CAL_BACKEND_OPEN_SUCCESS:
        add_backend (factory, uristr, backend);
        return backend;

    case CAL_BACKEND_OPEN_ERROR:
        g_object_unref (backend);

        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_ERROR,
            CORBA_OBJECT_NIL,
            &ev);

        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("open_backend(): could not notify the listener");

        CORBA_exception_free (&ev);
        return NULL;

    case CAL_BACKEND_OPEN_NOT_FOUND:
        g_object_unref (backend);

        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_NOT_FOUND,
            CORBA_OBJECT_NIL,
            &ev);

        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("open_backend(): could not notify the listener");

        CORBA_exception_free (&ev);
        return NULL;

    case CAL_BACKEND_OPEN_PERMISSION_DENIED :
        g_object_unref (backend);

        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_PERMISSION_DENIED,
            CORBA_OBJECT_NIL,
            &ev);

        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("open_backend(): could not notify the listener");

        CORBA_exception_free (&ev);
        return NULL;

    default:
        g_assert_not_reached ();
        return NULL;
    }
}

/* Adds a listener to a calendar backend by creating a calendar client interface
 * object.
 */
static void
add_calendar_client (CalFactory *factory,
             CalBackend *backend,
             GNOME_Evolution_Calendar_Listener listener)
{
    Cal *cal;
    CORBA_Environment ev;

    cal = cal_new (backend, listener);
    if (!cal) {
        g_message ("add_calendar_client(): could not create the calendar client interface");

        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_ERROR,
            CORBA_OBJECT_NIL,
            &ev);
        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("add_calendar_client(): could not notify the listener");

        CORBA_exception_free (&ev);
        return;
    }

    cal_backend_add_cal (backend, cal);

    CORBA_exception_init (&ev);
    GNOME_Evolution_Calendar_Listener_notifyCalOpened (
        listener,
        GNOME_Evolution_Calendar_Listener_SUCCESS,
        BONOBO_OBJREF (cal),
        &ev);

    if (ev._major != CORBA_NO_EXCEPTION) {
        g_message ("add_calendar_client(): could not notify the listener");
        bonobo_object_unref (BONOBO_OBJECT (cal));
    }

    CORBA_exception_free (&ev);
}

/* Add a uri to a string list */
static void
add_uri (gpointer key, gpointer value, gpointer data)
{
    CalFactoryUriData *cfud = data;
    CalFactory *factory = cfud->factory;    
    GNOME_Evolution_Calendar_StringSeq *list = cfud->list;
    GNOME_Evolution_Calendar_CalMode mode = cfud->mode;
    char *uri_string = key;
    CalBackend *backend;

    switch (mode) {
    case GNOME_Evolution_Calendar_MODE_LOCAL:
        backend = lookup_backend (factory, uri_string, NULL);
        if (backend == NULL || cal_backend_get_mode (backend) != CAL_MODE_LOCAL)
            return;
        break;      
    case GNOME_Evolution_Calendar_MODE_REMOTE:
        backend = lookup_backend (factory, uri_string, NULL);
        if (backend == NULL || cal_backend_get_mode (backend) != CAL_MODE_REMOTE)
            return;
        break;      
    case GNOME_Evolution_Calendar_MODE_ANY:
        break;
    }
    
    list->_buffer[list->_length] = CORBA_string_dup (uri_string);
    list->_length++;
}

/* Job data */
typedef struct {
    CalFactory *factory;
    char *uri;
    gboolean only_if_exists;
    GNOME_Evolution_Calendar_Listener listener;
} OpenJobData;

/* Job handler for the open calendar command */
static void
open_fn (gpointer data)
{
    OpenJobData *jd;
    CalFactory *factory;
    gboolean only_if_exists;
    GNOME_Evolution_Calendar_Listener listener;
    CalBackend *backend;
    CORBA_Environment ev;
    char *uri_string;

    jd = data;
    g_assert (jd->uri != NULL);

    /* Check the URI */
    uri_string = g_strdup (jd->uri);
    g_free (jd->uri);

    only_if_exists = jd->only_if_exists;
    factory = jd->factory;
    listener = jd->listener;
    g_free (jd);

    if (!uri_string) {
        CORBA_exception_init (&ev);
        GNOME_Evolution_Calendar_Listener_notifyCalOpened (
            listener,
            GNOME_Evolution_Calendar_Listener_ERROR,
            CORBA_OBJECT_NIL,
            &ev);

        if (ev._major != CORBA_NO_EXCEPTION)
            g_message ("open_fn(): Could not notify the listener!");

        CORBA_exception_free (&ev);
        goto out;
    }

    /* Look up the backend and create it if needed */

    backend = lookup_backend (factory, uri_string, NULL);

    if (!backend)
        backend = open_backend (factory, uri_string, only_if_exists, listener);
    
    g_free (uri_string);
    
    if (backend)
        add_calendar_client (factory, backend, listener);

 out:

    CORBA_exception_init (&ev);
    CORBA_Object_release (listener, &ev);

    if (ev._major != CORBA_NO_EXCEPTION)
        g_message ("open_fn(): could not release the listener");

    CORBA_exception_free (&ev);
}



static void
impl_CalFactory_open (PortableServer_Servant servant,
              const CORBA_char *str_uri,
              CORBA_boolean only_if_exists,
              GNOME_Evolution_Calendar_Listener listener,
              CORBA_Environment *ev)
{
    CalFactory *factory;
    CalFactoryPrivate *priv;
    CORBA_Environment ev2;
    gboolean result;
    OpenJobData *jd;
    GNOME_Evolution_Calendar_Listener listener_copy;
    GType *type;
    EUri *uri;

    factory = CAL_FACTORY (bonobo_object_from_servant (servant));
    priv = factory->priv;

    /* check URI to see if we support it */

    uri = e_uri_new (str_uri);
    if (!uri) {
        CORBA_exception_set (ev, CORBA_USER_EXCEPTION,
                     ex_GNOME_Evolution_Calendar_CalFactory_InvalidURI,
                     NULL);
        return;
    }

    type = g_hash_table_lookup (priv->methods, uri->protocol);

    e_uri_free (uri);
    if (!type) {
        CORBA_exception_set (ev, CORBA_USER_EXCEPTION,
                     ex_GNOME_Evolution_Calendar_CalFactory_UnsupportedMethod,
                     NULL);
        return;
    }
        
    /* duplicate the listener object */
    CORBA_exception_init (&ev2);
    result = CORBA_Object_is_nil (listener, &ev2);

    if (ev2._major != CORBA_NO_EXCEPTION || result) {
        CORBA_exception_set (ev, CORBA_USER_EXCEPTION,
                     ex_GNOME_Evolution_Calendar_CalFactory_NilListener,
                     NULL);

        CORBA_exception_free (&ev2);
        return;
    }
    CORBA_exception_free (&ev2);

    CORBA_exception_init (&ev2);
    listener_copy = CORBA_Object_duplicate (listener, &ev2);

    if (ev2._major != CORBA_NO_EXCEPTION) {
        g_message ("CalFactory_open(): could not duplicate the listener");
        CORBA_exception_free (&ev2);
        CORBA_exception_set (ev, CORBA_USER_EXCEPTION,
                     ex_GNOME_Evolution_Calendar_CalFactory_NilListener,
                     NULL);
        return;
    }

    CORBA_exception_free (&ev2);

    /* add new asynchronous job */
    jd = g_new (OpenJobData, 1);
    jd->factory = factory;
    jd->uri = g_strdup (str_uri);
    jd->only_if_exists = only_if_exists;
    jd->listener = listener_copy;

    job_add (open_fn, jd);
}

static GNOME_Evolution_Calendar_StringSeq *
impl_CalFactory_uriList (PortableServer_Servant servant,
             GNOME_Evolution_Calendar_CalMode mode,
             CORBA_Environment *ev)
{
    CalFactory *factory;
    CalFactoryPrivate *priv;
    CalFactoryUriData cfud;
    GNOME_Evolution_Calendar_StringSeq *list;

    factory = CAL_FACTORY (bonobo_object_from_servant (servant));
    priv = factory->priv;

    list = GNOME_Evolution_Calendar_StringSeq__alloc ();
    list->_length = 0;
    list->_maximum = g_hash_table_size (priv->backends); 
    list->_buffer = CORBA_sequence_CORBA_string_allocbuf (list->_maximum);

    cfud.factory = factory; 
    cfud.mode = mode;   
    cfud.list = list;
    g_hash_table_foreach (priv->backends, add_uri, &cfud);
    
    return list;    

}



/**
 * 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, 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_foreach (priv->methods, free_method, NULL);
    g_hash_table_destroy (priv->methods);
    priv->methods = NULL;

    /* Should we assert that there are no more backends? */

    g_hash_table_foreach (priv->backends, free_backend, NULL);
    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->open = impl_CalFactory_open;
    epv->uriList = impl_CalFactory_uriList;
}

/* 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 (g_str_hash, g_str_equal);
    priv->backends = g_hash_table_new (g_str_hash, g_str_equal);
    priv->registered = FALSE;
}

BONOBO_TYPE_FUNC_FULL (CalFactory,
               GNOME_Evolution_Calendar_CalFactory,
               PARENT_TYPE,
               cal_factory);

/* Returns the lowercase version of a string */
static char *
str_tolower (const char *s)
{
    char *str;
    unsigned char *p;

    str = g_strdup (s);
    for (p = str; *p; p++)
        if (isalpha (*p))
            *p = tolower (*p);

    return str;
}

/**
 * cal_factory_oaf_register:
 * @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_oaf_register (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_message ("cal_factory_oaf_register(): Cannot register the calendar factory: "
               "not listed");
        break;

    case Bonobo_ACTIVATION_REG_ALREADY_ACTIVE:
        g_message ("cal_factory_oaf_register(): Cannot register the calendar factory: "
               "already active");
        break;

    case Bonobo_ACTIVATION_REG_ERROR:
    default:
        g_message ("cal_factory_oaf_register(): 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, GType backend_type)
{
    CalFactoryPrivate *priv;
    GType *type;
    char *method_str;

    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 = str_tolower (method);

    type = g_hash_table_lookup (priv->methods, method_str);
    if (type) {
        g_message ("cal_factory_register_method(): Method `%s' already registered!",
               method_str);
        g_free (method_str);
        return;
    }

    type = g_new (GType, 1);
    *type = backend_type;

    g_hash_table_insert (priv->methods, method_str, type);
}

/**
 * cal_factory_get_n_backends:
 * @factory: A calendar factory.
 * 
 * Queries the number of running calendar backends in a calendar factory.
 * 
 * Return value: Number of running backends.
 **/
int
cal_factory_get_n_backends (CalFactory *factory)
{
    CalFactoryPrivate *priv;

    g_return_val_if_fail (factory != NULL, -1);
    g_return_val_if_fail (IS_CAL_FACTORY (factory), -1);

    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);
}