path: root/camel/camel-disco-store.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-disco-store.c: abstract class for a disconnectable remote store */

/*
 *  Authors: Dan Winship <danw@ximian.com>
 *
 *  Copyright 2001 Ximian, Inc.
 *
 * 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.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "camel-disco-store.h"
#include "camel-disco-diary.h"
#include "camel-exception.h"
#include "camel-session.h"

#define CDS_CLASS(o) (CAMEL_DISCO_STORE_CLASS (CAMEL_OBJECT_GET_CLASS (o)))

static CamelRemoteStoreClass *remote_store_class = NULL;

static void disco_construct (CamelService *service, CamelSession *session,
                 CamelProvider *provider, CamelURL *url,
                 CamelException *ex);
static gboolean disco_connect (CamelService *service, CamelException *ex);
static void disco_cancel_connect (CamelService *service);
static gboolean disco_disconnect (CamelService *service, gboolean clean, CamelException *ex);
static CamelFolder *disco_get_folder (CamelStore *store, const char *name,
                      guint32 flags, CamelException *ex);
static CamelFolderInfo *disco_get_folder_info (CamelStore *store,
                           const char *top, guint32 flags,
                           CamelException *ex);
static void set_status (CamelDiscoStore *disco_store,
            CamelDiscoStoreStatus status,
            CamelException *ex);
static gboolean can_work_offline (CamelDiscoStore *disco_store);

static void
camel_disco_store_class_init (CamelDiscoStoreClass *camel_disco_store_class)
{
    CamelServiceClass *camel_service_class =
        CAMEL_SERVICE_CLASS (camel_disco_store_class);
    CamelStoreClass *camel_store_class =
        CAMEL_STORE_CLASS (camel_disco_store_class);

    remote_store_class = CAMEL_REMOTE_STORE_CLASS (camel_type_get_global_classfuncs (camel_remote_store_get_type ()));

    /* virtual method definition */
    camel_disco_store_class->set_status = set_status;
    camel_disco_store_class->can_work_offline = can_work_offline;

    /* virtual method overload */
    camel_service_class->construct = disco_construct;
    camel_service_class->connect = disco_connect;
    camel_service_class->disconnect = disco_disconnect;
    camel_service_class->cancel_connect = disco_cancel_connect;

    camel_store_class->get_folder = disco_get_folder;
    camel_store_class->get_folder_info = disco_get_folder_info;
}

CamelType
camel_disco_store_get_type (void)
{
    static CamelType camel_disco_store_type = CAMEL_INVALID_TYPE;

    if (camel_disco_store_type == CAMEL_INVALID_TYPE) {
        camel_disco_store_type = camel_type_register (
            CAMEL_REMOTE_STORE_TYPE, "CamelDiscoStore",
            sizeof (CamelDiscoStore),
            sizeof (CamelDiscoStoreClass),
            (CamelObjectClassInitFunc) camel_disco_store_class_init,
            NULL,
            NULL,
            NULL);
    }

    return camel_disco_store_type;
}

static void
disco_construct (CamelService *service, CamelSession *session,
         CamelProvider *provider, CamelURL *url,
         CamelException *ex)
{
    CamelDiscoStore *disco = CAMEL_DISCO_STORE (service);

    CAMEL_SERVICE_CLASS (remote_store_class)->construct (service, session, provider, url, ex);
    if (camel_exception_is_set (ex))
        return;

    disco->status = camel_session_is_online (session) ?
        CAMEL_DISCO_STORE_ONLINE : CAMEL_DISCO_STORE_OFFLINE;
}

static gboolean
disco_connect (CamelService *service, CamelException *ex)
{
    CamelDiscoStore *store = CAMEL_DISCO_STORE (service);
    CamelDiscoStoreStatus status;

    status = camel_disco_store_status (store);
    if (status != CAMEL_DISCO_STORE_OFFLINE) {
        if (!CAMEL_SERVICE_CLASS (remote_store_class)->connect (service, ex)) {
            status = camel_disco_store_status (store);
            if (status != CAMEL_DISCO_STORE_OFFLINE)
                return FALSE;
            camel_exception_clear (ex);
        }
    }

    switch (status) {
    case CAMEL_DISCO_STORE_ONLINE:
    case CAMEL_DISCO_STORE_RESYNCING:
        if (!CDS_CLASS (service)->connect_online (service, ex))
            return FALSE;
        if (camel_disco_diary_empty (store->diary))
            return TRUE;

        /* Need to resync */
        store->status = CAMEL_DISCO_STORE_RESYNCING;
        camel_disco_diary_replay (store->diary, ex);
        store->status = CAMEL_DISCO_STORE_ONLINE;
        if (camel_exception_is_set (ex))
            return FALSE;

        if (!camel_service_disconnect (service, TRUE, ex))
            return FALSE;
        return camel_service_connect (service, ex);

    case CAMEL_DISCO_STORE_OFFLINE:
        return CDS_CLASS (service)->connect_offline (service, ex);
    }

    g_assert_not_reached ();
    return FALSE;
}

static void
disco_cancel_connect (CamelService *service)
{
    CamelDiscoStore *store = CAMEL_DISCO_STORE (service);

    /* Fall back */
    store->status = CAMEL_DISCO_STORE_OFFLINE;

    CAMEL_SERVICE_CLASS (remote_store_class)->cancel_connect (service);
}

static gboolean
disco_disconnect (CamelService *service, gboolean clean, CamelException *ex)
{
    CamelDiscoStore *store = CAMEL_DISCO_STORE (service);

    switch (camel_disco_store_status (store)) {
    case CAMEL_DISCO_STORE_ONLINE:
    case CAMEL_DISCO_STORE_RESYNCING:
        if (!CDS_CLASS (service)->disconnect_online (service, clean, ex))
            return FALSE;
        break;

    case CAMEL_DISCO_STORE_OFFLINE:
        if (!CDS_CLASS (service)->disconnect_offline (service, clean, ex))
            return FALSE;
        break;

    }

    return CAMEL_SERVICE_CLASS (remote_store_class)->disconnect (service, clean, ex);
}

static CamelFolder *
disco_get_folder (CamelStore *store, const char *name,
          guint32 flags, CamelException *ex)
{
    CamelDiscoStore *disco_store = CAMEL_DISCO_STORE (store);
    
    switch (camel_disco_store_status (disco_store)) {
    case CAMEL_DISCO_STORE_ONLINE:
        return CDS_CLASS (store)->get_folder_online (store, name, flags, ex);
        
    case CAMEL_DISCO_STORE_OFFLINE:
        return CDS_CLASS (store)->get_folder_offline (store, name, flags, ex);
        
    case CAMEL_DISCO_STORE_RESYNCING:
        return CDS_CLASS (store)->get_folder_resyncing (store, name, flags, ex);    
    }
    
    g_assert_not_reached ();
    return NULL;
}

static CamelFolderInfo *
disco_get_folder_info (CamelStore *store, const char *top,
               guint32 flags, CamelException *ex)
{
    CamelDiscoStore *disco_store = CAMEL_DISCO_STORE (store);

    /* Do this first so if we get forced offline, we'll switch to
     * the correct branch below. (FIXME: This only works because
     * we know that get_folder_info is the first call that the
     * mailer makes on a store.)
     */
    if (CAMEL_SERVICE (store)->status == CAMEL_SERVICE_DISCONNECTED) {
        if (!camel_service_connect (CAMEL_SERVICE (store), ex))
            return NULL;
    }

    switch (camel_disco_store_status (disco_store)) {
    case CAMEL_DISCO_STORE_ONLINE:
        return CDS_CLASS (store)->get_folder_info_online (store, top, flags, ex);
        
    case CAMEL_DISCO_STORE_OFFLINE:
        /* Can't edit subscriptions while offline */
        if ((store->flags & CAMEL_STORE_SUBSCRIPTIONS) &&
            !(flags & CAMEL_STORE_FOLDER_INFO_SUBSCRIBED)) {
            camel_disco_store_check_online (disco_store, ex);
            return NULL;
        }
        
        return CDS_CLASS (store)->get_folder_info_offline (store, top, flags, ex);
        
    case CAMEL_DISCO_STORE_RESYNCING:
        return CDS_CLASS (store)->get_folder_info_resyncing (store, top, flags, ex);
    }
    
    g_assert_not_reached ();
    return NULL;
}


/**
 * camel_disco_store_status:
 * @store: a disconnectable store
 *
 * Return value: the current online/offline status of @store.
 **/
CamelDiscoStoreStatus
camel_disco_store_status (CamelDiscoStore *store)
{
    g_return_val_if_fail (CAMEL_IS_DISCO_STORE (store), CAMEL_DISCO_STORE_ONLINE);

    return store->status;
}


static void
set_status (CamelDiscoStore *disco_store, CamelDiscoStoreStatus status,
        CamelException *ex)
{
    if (disco_store->status == status)
        return;

    camel_store_sync (CAMEL_STORE (disco_store), ex);
    if (camel_exception_is_set (ex))
        return;
    if (!camel_service_disconnect (CAMEL_SERVICE (disco_store), TRUE, ex))
        return;

    disco_store->status = status;
    camel_service_connect (CAMEL_SERVICE (disco_store), ex);
}

/**
 * camel_disco_store_set_status:
 * @store: a disconnectable store
 * @status: the new status
 * @ex: a CamelException
 *
 * Sets @store to @status. If an error occurrs and the status cannot
 * be set to @status, @ex will be set.
 **/
void
camel_disco_store_set_status (CamelDiscoStore *store,
                  CamelDiscoStoreStatus status,
                  CamelException *ex)
{
    CDS_CLASS (store)->set_status (store, status, ex);
}


static gboolean
can_work_offline (CamelDiscoStore *disco_store)
{
    g_warning ("CamelDiscoStore::can_work_offline not implemented for `%s'",
           camel_type_to_name (CAMEL_OBJECT_GET_TYPE (disco_store)));
    return FALSE;
}

/**
 * camel_disco_store_can_work_offline:
 * @store: a disconnectable store
 *
 * Return value: whether or not @store can be used offline. (Will be
 * %FALSE if the store is not caching data to local disk, for example.)
 **/
gboolean
camel_disco_store_can_work_offline (CamelDiscoStore *store)
{
    return CDS_CLASS (store)->can_work_offline (store);
}


/**
 * camel_disco_store_check_online:
 * @store: a disconnectable store
 * @ex: a CamelException
 *
 * This checks that @store is online, and sets @ex if it is not. This
 * can be used as a simple way to set a generic error message in @ex
 * for operations that won't work offline.
 *
 * Return value: whether or not @store is online.
 **/
gboolean
camel_disco_store_check_online (CamelDiscoStore *store, CamelException *ex)
{
    if (camel_disco_store_status (store) != CAMEL_DISCO_STORE_ONLINE) {
        camel_exception_set (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                     _("You must be working online to "
                       "complete this operation"));
        return FALSE;
    }

    return TRUE;
}