path: root/camel/providers/imap/camel-imap-store.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-imap-store.c : class for an imap store */

/*
 *  Authors: Jeffrey Stedfast <fejj@helixcode.com>
 *
 *  Copyright 2000 Helix Code, Inc. (www.helixcode.com)
 *
 *  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 2 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, write to the Free Software
 *  Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA.
 *
 */


#include <config.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include <e-util/e-util.h>

#include "camel-imap-store.h"
#include "camel-imap-folder.h"
#include "camel-imap-utils.h"
#include "camel-folder.h"
#include "camel-exception.h"
#include "camel-session.h"
#include "camel-stream.h"
#include "camel-stream-buffer.h"
#include "camel-stream-fs.h"
#include "camel-url.h"
#include "string-utils.h"

#define d(x) x

/* Specified in RFC 2060 */
#define IMAP_PORT 143

static CamelServiceClass *service_class = NULL;

static void finalize (GtkObject *object);
static gboolean imap_create (CamelFolder *folder, CamelException *ex);
static gboolean imap_connect (CamelService *service, CamelException *ex);
static gboolean imap_disconnect (CamelService *service, CamelException *ex);
static GList *query_auth_types (CamelService *service, CamelException *ex);
static void free_auth_types (CamelService *service, GList *authtypes);
static char *get_name (CamelService *service, gboolean brief);
static CamelFolder *get_folder (CamelStore *store, const char *folder_name, gboolean create,
                CamelException *ex);
static char *get_folder_name (CamelStore *store, const char *folder_name, CamelException *ex);
static gboolean imap_noop (gpointer data);
/*static gboolean stream_is_alive (CamelStream *istream);*/
static int camel_imap_status (char *cmdid, char *respbuf);

static void
camel_imap_store_class_init (CamelImapStoreClass *camel_imap_store_class)
{
    /* virtual method overload */
    GtkObjectClass *object_class =
        GTK_OBJECT_CLASS (camel_imap_store_class);
    CamelServiceClass *camel_service_class =
        CAMEL_SERVICE_CLASS (camel_imap_store_class);
    CamelStoreClass *camel_store_class =
        CAMEL_STORE_CLASS (camel_imap_store_class);
    
    service_class = gtk_type_class (camel_service_get_type ());

    /* virtual method overload */
    object_class->finalize = finalize;

    camel_service_class->connect = imap_connect;
    camel_service_class->disconnect = imap_disconnect;
    camel_service_class->query_auth_types = query_auth_types;
    camel_service_class->free_auth_types = free_auth_types;
    camel_service_class->get_name = get_name;

    camel_store_class->get_folder = get_folder;
    camel_store_class->get_folder_name = get_folder_name;
}

static void
camel_imap_store_init (gpointer object, gpointer klass)
{
    CamelService *service = CAMEL_SERVICE (object);
    CamelStore *store = CAMEL_STORE (object);

    service->url_flags = (CAMEL_SERVICE_URL_NEED_USER |
                  CAMEL_SERVICE_URL_NEED_HOST |
                  CAMEL_SERVICE_URL_ALLOW_PATH);

    store->folders = g_hash_table_new (g_str_hash, g_str_equal);
    CAMEL_IMAP_STORE (store)->dir_sep = NULL;
    CAMEL_IMAP_STORE (store)->current_folder = NULL;
    CAMEL_IMAP_STORE (store)->timeout_id = 0;
}

GtkType
camel_imap_store_get_type (void)
{
    static GtkType camel_imap_store_type = 0;
    
    if (!camel_imap_store_type) {
        GtkTypeInfo camel_imap_store_info = 
        {
            "CamelImapStore",
            sizeof (CamelImapStore),
            sizeof (CamelImapStoreClass),
            (GtkClassInitFunc) camel_imap_store_class_init,
            (GtkObjectInitFunc) camel_imap_store_init,
                /* reserved_1 */ NULL,
                /* reserved_2 */ NULL,
            (GtkClassInitFunc) NULL,
        };

        camel_imap_store_type = gtk_type_unique (CAMEL_STORE_TYPE, &camel_imap_store_info);
    }
    
    return camel_imap_store_type;
}

static void
finalize (GtkObject *object)
{
    CamelException ex;
    
    camel_exception_init (&ex);
    imap_disconnect (CAMEL_SERVICE (object), &ex);
    camel_exception_clear (&ex);
}

static CamelServiceAuthType password_authtype = {
    "Password",
    
    "This option will connect to the IMAP server using a "
    "plaintext password.",
    
    "",
    TRUE
};

static gboolean
try_connect (CamelService *service, CamelException *ex)
{
    struct hostent *h;
    struct sockaddr_in sin;
    gint fd;
    
    h = camel_service_gethost (service, ex);
    if (!h)
        return FALSE;
    
    sin.sin_family = h->h_addrtype;
    sin.sin_port = htons (service->url->port ? service->url->port : IMAP_PORT);
    memcpy (&sin.sin_addr, h->h_addr, sizeof (sin.sin_addr));
    
    fd = socket (h->h_addrtype, SOCK_STREAM, 0);
    if (fd == -1 || connect (fd, (struct sockaddr *)&sin, sizeof (sin)) == -1) {    
        /* We don't want to set a CamelException here */
        
        if (fd > -1)
            close (fd);
        
        return FALSE;
    }
    
    close (fd);
    return TRUE;
}

static GList *
query_auth_types (CamelService *service, CamelException *ex)
{
    GList *ret = NULL;
    gboolean passwd = TRUE;
    
    if (service->url) {
        passwd = try_connect (service, ex);
        if (camel_exception_get_id (ex) != CAMEL_EXCEPTION_NONE)
            return NULL;
    }
    
    if (passwd)
        ret = g_list_append (ret, &password_authtype);
    
    if (!ret) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not connect to IMAP server on %s.",
                      service->url->host ? service->url->host : 
                      "(unknown host)");
    }                     
    
    return ret;
}

static void
free_auth_types (CamelService *service, GList *authtypes)
{
    g_list_free (authtypes);
}

static char *
get_name (CamelService *service, gboolean brief)
{
    if (brief)
        return g_strdup_printf ("IMAP server %s", service->url->host);
    else {
        return g_strdup_printf ("IMAP service for %s on %s",
                    service->url->user,
                    service->url->host);
    }
}

static gboolean
imap_connect (CamelService *service, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (service);
    struct hostent *h;
    struct sockaddr_in sin;
    gint fd, status;
    gchar *buf, *msg, *result, *errbuf = NULL;
    gboolean authenticated = FALSE;

    /* FIXME: do we really need this here? */
    if (store->timeout_id) {
        gtk_timeout_remove (store->timeout_id);
        store->timeout_id = 0;
    }
    
    h = camel_service_gethost (service, ex);
    if (!h)
        return FALSE;

    /* connect to the IMAP server */
    sin.sin_family = h->h_addrtype;
    if (service->url->port)
        sin.sin_port = htons(service->url->port);
    else
        sin.sin_port = htons(IMAP_PORT);
    
    memcpy (&sin.sin_addr, h->h_addr, sizeof (sin.sin_addr));
    
    fd = socket (h->h_addrtype, SOCK_STREAM, 0);
    if (fd == -1 || connect (fd, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not connect to %s (port %d): %s",
                      service->url->host ? service->url->host : "(unknown host)", 
                      service->url->port ? service->url->port : IMAP_PORT,
                      strerror(errno));
        if (fd > -1)
            close (fd);
        
        return FALSE;
    }

    /* parent class conect initialization */
    service_class->connect (service, ex);
    
    store->ostream = camel_stream_fs_new_with_fd (fd);
    store->istream = camel_stream_buffer_new (store->ostream, CAMEL_STREAM_BUFFER_READ);
    store->command = 0;
    g_free (store->dir_sep);
    store->dir_sep = g_strdup ("/");  /* default dir sep */
    
    /* Read the greeting, if any. */
    buf = camel_stream_buffer_read_line (CAMEL_STREAM_BUFFER (store->istream));
    if (!buf) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not read greeting from IMAP "
                      "server: %s",
                      camel_exception_get_description (ex));
        
        imap_disconnect (service, ex);
        return FALSE;
    }
    g_free (buf);

    /* authenticate the user */
    while (!authenticated) {
        if (errbuf) {
            /* We need to un-cache the password before prompting again */
            camel_session_query_authenticator (camel_service_get_session (service),
                               CAMEL_AUTHENTICATOR_TELL, NULL,
                               TRUE, service, "password", ex);
            g_free (service->url->passwd);
            service->url->passwd = NULL;
        }

        if (!service->url->authmech && !service->url->passwd) {
            gchar *prompt;
            
            prompt = g_strdup_printf ("%sPlease enter the IMAP password for %s@%s",
                          errbuf ? errbuf : "", service->url->user, h->h_name);
            service->url->passwd =
                camel_session_query_authenticator (camel_service_get_session (service),
                                   CAMEL_AUTHENTICATOR_ASK, prompt,
                                   TRUE, service, "password", ex);
            g_free (prompt);
            g_free (errbuf);
            errbuf = NULL;
            
            if (!service->url->passwd) {
                imap_disconnect (service, ex);
                return FALSE;
            }
        }

        status = camel_imap_command (store, NULL, &msg, "LOGIN \"%s\" \"%s\"",
                         service->url->user,
                         service->url->passwd);

        if (status != CAMEL_IMAP_OK) {
            errbuf = g_strdup_printf ("Unable to authenticate to IMAP server.\n"
                          "Error sending password: %s\n\n",
                          msg ? msg : "(Unknown)");
        } else {
            g_message ("IMAP Service sucessfully authenticated user %s", service->url->user);
            authenticated = TRUE;
        }
    }
    
    /* Now lets find out the IMAP capabilities */
    status = camel_imap_command_extended (store, NULL, &result, "CAPABILITY");
    
    if (status != CAMEL_IMAP_OK) {
        /* Non-fatal error, but we should still warn the user... */
        CamelService *service = CAMEL_SERVICE (store);
        
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not get capabilities on IMAP server %s: %s.",
                      service->url->host, 
                      status != CAMEL_IMAP_FAIL && result ? result :
                      "Unknown error");
    }

    /* parse for capabilities here. */
    if (e_strstrcase (result, "IMAP4REV1"))
        store->server_level = IMAP_LEVEL_IMAP4REV1;
    else if (e_strstrcase (result, "IMAP4"))
        store->server_level = IMAP_LEVEL_IMAP4;
    else
        store->server_level = IMAP_LEVEL_UNKNOWN;
    
    if ((store->server_level >= IMAP_LEVEL_IMAP4REV1) || (e_strstrcase (result, "STATUS")))
        store->has_status_capability = TRUE;
    else
        store->has_status_capability = FALSE;
    
    g_free (result);
    
    /* We now need to find out which directory separator this daemon uses */
    status = camel_imap_command_extended (store, NULL, &result, "LIST \"\" \"\"");
    
    if (status != CAMEL_IMAP_OK) {
        /* Again, this is non-fatal */
        CamelService *service = CAMEL_SERVICE (store);
        
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not get directory separator on IMAP server %s: %s.",
                      service->url->host, 
                      status != CAMEL_IMAP_FAIL && result ? result :
                      "Unknown error");
    } else {
        char *flags, *sep, *folder;
        
        if (imap_parse_list_response (result, "", &flags, &sep, &folder)) {
            if (*sep) {
                g_free (store->dir_sep);
                store->dir_sep = g_strdup (sep);
            }
        }
        
        g_free (flags);
        g_free (sep);
        g_free (folder);
    }
    
    /* default directory separator */
    if (!store->dir_sep)
        store->dir_sep = g_strdup ("/");
    
    g_free (result);

    /* Lets add a timeout so that we can hopefully prevent getting disconnected */
    store->timeout_id = gtk_timeout_add (600000, imap_noop, store);
    
    return TRUE;
}

static gboolean
imap_disconnect (CamelService *service, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (service);
    char *result;
    int status;
    
    if (!service->connected)
        return TRUE;
    
    /* send the logout command */
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (service), NULL, &result, "LOGOUT");
    if (status != CAMEL_IMAP_OK) {
        /* Oh fuck it, we're disconnecting anyway... */
    }
    g_free (result);
    
    if (!service_class->disconnect (service, ex))
        return FALSE;
    
    if (store->istream) {
        gtk_object_unref (GTK_OBJECT (store->istream));
        store->istream = NULL;
    }
    
    if (store->ostream) {
        gtk_object_unref (GTK_OBJECT (store->ostream));
        store->ostream = NULL;
    }
    
    g_free (store->dir_sep);
    store->dir_sep = NULL;
    
    store->current_folder = NULL;
    
    if (store->timeout_id) {
        gtk_timeout_remove (store->timeout_id);
        store->timeout_id = 0;
    }
    
    return TRUE;
}

const gchar *
camel_imap_store_get_toplevel_dir (CamelImapStore *store)
{
    CamelURL *url = CAMEL_SERVICE (store)->url;
    
    g_assert (url != NULL);
    return url->path;
}

static gboolean
imap_folder_exists (CamelFolder *folder)
{
    CamelStore *store = CAMEL_STORE (folder->parent_store);
    CamelURL *url = CAMEL_SERVICE (store)->url;
    gchar *result, *folder_path, *dir_sep;
    gint status;
    
    dir_sep = CAMEL_IMAP_STORE (folder->parent_store)->dir_sep;
    
    if (url && url->path && *(url->path + 1) && strcmp (folder->full_name, "INBOX"))
        folder_path = g_strdup_printf ("%s%s%s", url->path + 1, dir_sep, folder->full_name);
    else
        folder_path = g_strdup (folder->full_name);
    
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), NULL,
                          &result, "EXAMINE %s", folder_path);
    
    if (status != CAMEL_IMAP_OK) {
        g_free (result);
        g_free (folder_path);
        return FALSE;
    }
    g_free (folder_path);
    g_free (result);
    
    return TRUE;
}

static gboolean
imap_create (CamelFolder *folder, CamelException *ex)
{
    CamelStore *store = CAMEL_STORE (folder->parent_store);
    CamelURL *url = CAMEL_SERVICE (store)->url;
    gchar *result, *folder_path, *dir_sep;
    gint status;
    
    g_return_val_if_fail (folder != NULL, FALSE);
    
    if (!(folder->full_name || folder->name)) {
        camel_exception_set (ex, CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }
    
    if (!strcmp (folder->full_name, "INBOX"))
        return TRUE;
    
    if (imap_folder_exists (folder))
        return TRUE;
    
        /* create the directory for the subfolder */
    dir_sep = CAMEL_IMAP_STORE (folder->parent_store)->dir_sep;
    
    if (url && url->path && *(url->path + 1) && strcmp (folder->full_name, "INBOX"))
        folder_path = g_strdup_printf ("%s%s%s", url->path + 1, dir_sep, folder->full_name);
    else
        folder_path = g_strdup (folder->full_name);
    
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), NULL,
                          &result, "CREATE %s", folder_path);
    
    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not CREATE %s on IMAP server %s: %s.",
                      folder_path, service->url->host,
                      status != CAMEL_IMAP_FAIL && result ? result :
                      "Unknown error");
        g_free (result);
        g_free (folder_path);
        return FALSE;
    }
    g_free (folder_path);
    g_free (result);
    
    return TRUE;
}

static gboolean
folder_is_selectable (CamelStore *store, const char *folder_path)
{
    char *result, *flags, *sep, *folder;
    int status;
    
    if (!strcmp (folder_path, "INBOX"))
        return TRUE;
    
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (store), NULL,
                          &result, "LIST \"\" %s", folder_path);
    if (status != CAMEL_IMAP_OK) {
        g_free (result);
        return FALSE;
    }
    
    if (imap_parse_list_response (result, "", &flags, &sep, &folder)) {
        gboolean retval;
        
        retval = !e_strstrcase (flags, "NoSelect");
        g_free (flags);
        g_free (sep);
        g_free (folder);
        
        return retval;
    }
    g_free (flags);
    g_free (sep);
    g_free (folder);
    
    return FALSE;
}

static CamelFolder *
get_folder (CamelStore *store, const char *folder_name, gboolean create, CamelException *ex)
{
    CamelURL *url = CAMEL_SERVICE (store)->url;
    CamelFolder *new_folder;
    char *folder_path, *dir_sep;
    
    g_return_val_if_fail (store != NULL, NULL);
    g_return_val_if_fail (folder_name != NULL, NULL);
    
    dir_sep = CAMEL_IMAP_STORE (store)->dir_sep;
    
    /* if we're trying to get the top-level dir, we really want the namespace */
    if (!strcmp (folder_name, dir_sep))
        folder_path = g_strdup (url->path + 1);
    else
        folder_path = g_strdup (folder_name);
    
    new_folder = camel_imap_folder_new (store, folder_path, ex);
    
    /* this is the top-level dir, we already know it exists - it has to! */
    if (!strcmp (folder_name, dir_sep))
        return new_folder;
    
    if (create && !imap_create (new_folder, ex)) {
        if (!folder_is_selectable (store, folder_path)) {
            camel_exception_clear (ex);
            new_folder->can_hold_messages = FALSE;
            return new_folder;
        } else {
            g_free (folder_path);
            gtk_object_unref (GTK_OBJECT (new_folder));     
            return NULL;
        }
    }
    
    return new_folder;
}

static gchar *
get_folder_name (CamelStore *store, const char *folder_name, CamelException *ex)
{
    return g_strdup (folder_name);
}

static gboolean
imap_noop (gpointer data)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (data);
    char *result;
    int status;

    status = camel_imap_command_extended (store, store->current_folder, &result, "NOOP");

    g_free (result);

    return TRUE;
}

#if 0
static gboolean
stream_is_alive (CamelStream *istream)
{
    CamelStreamFs *fs_stream;
    char buf;
    
    g_return_val_if_fail (istream != NULL, FALSE);
    
    fs_stream = CAMEL_STREAM_FS (CAMEL_STREAM_BUFFER (istream)->stream);
    g_return_val_if_fail (fs_stream->fd != -1, FALSE);
    
    if (read (fs_stream->fd, (void *) &buf, 0) == 0)
        return TRUE;
    
    return FALSE;
}
#endif

static int
camel_imap_status (char *cmdid, char *respbuf)
{
    char *retcode;
    
    if (respbuf) {
        if (!strncmp (respbuf, cmdid, strlen (cmdid))) {
            retcode = imap_next_word (respbuf);
            
            if (!strncmp (retcode, "OK", 2))
                return CAMEL_IMAP_OK;
            else if (!strncmp (retcode, "NO", 2))
                return CAMEL_IMAP_NO;
            else if (!strncmp (retcode, "BAD", 3))
                return CAMEL_IMAP_BAD;
        }
    }
    
    return CAMEL_IMAP_FAIL;
}

/**
 * camel_imap_command: Send a command to a IMAP server.
 * @store: the IMAP store
 * @folder: The folder to perform the operation in
 * @ret: a pointer to return the full server response in
 * @fmt: a printf-style format string, followed by arguments
 * 
 * This camel method sends the command specified by @fmt and the following
 * arguments to the connected IMAP store specified by @store. It then
 * reads the server's response and parses out the status code. If
 * the caller passed a non-NULL pointer for @ret, camel_imap_command
 * will set it to point to a buffer containing the rest of the
 * response from the IMAP server. (If @ret was passed but there was
 * no extended response, @ret will be set to NULL.) The caller function is
 * responsible for freeing @ret.
 * 
 * Return value: one of CAMEL_IMAP_OK (command executed successfully),
 * CAMEL_IMAP_NO (operational error message), CAMEL_IMAP_BAD (error
 * message from the server), or CAMEL_IMAP_FAIL (a protocol-level error
 * occurred, and Camel is uncertain of the result of the command.)
 **/
gint
camel_imap_command (CamelImapStore *store, CamelFolder *folder, char **ret, char *fmt, ...)
{
    CamelURL *url = CAMEL_SERVICE (store)->url;
    gchar *cmdbuf, *respbuf;
    gchar *cmdid;
    va_list ap;
    gint status = CAMEL_IMAP_OK;
    
    if (folder && store->current_folder != folder && strncmp (fmt, "CREATE", 5)) {
        /* We need to select the correct mailbox first */
        char *r, *folder_path, *dir_sep;
        int s;
        
        dir_sep = store->dir_sep;
        if (url && url->path && *(url->path + 1) && strcmp (folder->full_name, "INBOX"))
            folder_path = g_strdup_printf ("%s%s%s", url->path + 1, dir_sep, folder->full_name);
        else
            folder_path = g_strdup (folder->full_name);
        
        s = camel_imap_command_extended (store, NULL, &r, "SELECT %s", folder_path);
        g_free (folder_path);
        if (!r || s != CAMEL_IMAP_OK) {
            *ret = r;
            store->current_folder = NULL;
            
            return s;
        }
        
        g_free (r);
        
        store->current_folder = folder;
    }
    
    /* create the command */
    cmdid = g_strdup_printf ("A%.5d", store->command++);
    va_start (ap, fmt);
    cmdbuf = g_strdup_vprintf (fmt, ap);
    va_end (ap);
    
    d(fprintf (stderr, "sending : %s %s\r\n", cmdid, cmdbuf));
    
    if (camel_stream_printf (store->ostream, "%s %s\r\n", cmdid, cmdbuf) == -1) {
        g_free (cmdbuf);
        g_free (cmdid);
        if (*ret)
            *ret = g_strdup (strerror (errno));
        return CAMEL_IMAP_FAIL;
    }
    g_free (cmdbuf);
    
    /* Read the response */
    respbuf = camel_stream_buffer_read_line (CAMEL_STREAM_BUFFER (store->istream));
    if (respbuf == NULL) {
        if (*ret)
            *ret = g_strdup (strerror (errno));
        return CAMEL_IMAP_FAIL;
    }
    
    d(fprintf (stderr, "received: %s\n", respbuf ? respbuf : "(null)"));
    
    status = camel_imap_status (cmdid, respbuf);
    g_free (cmdid);

    if (ret) {
        if (status != CAMEL_IMAP_FAIL && respbuf) {
            char *word;
            
            word = imap_next_word (respbuf); /* word should now point to NO or BAD */
            
            *ret = g_strdup (imap_next_word (word));
        } else {
            *ret = NULL;
        }
    }

    g_free (respbuf);
    
    return status;
}

/**
 * camel_imap_command_extended: Send a command to a IMAP server and get
 * a multi-line response.
 * @store: the IMAP store
 * @folder: The folder to perform the operation in
 * @ret: a pointer to return the full server response in
 * @fmt: a printf-style format string, followed by arguments
 *
 * This camel method sends the IMAP command specified by @fmt and the
 * following arguments to the IMAP store specified by @store. If the
 * store is in a disconnected state, camel_imap_command_extended will first
 * re-connect the store before sending the specified IMAP command. It then
 * reads the server's response and parses out the status code. If the caller
 * passed a non-NULL pointer for @ret, camel_imap_command_extended will set
 * it to point to a buffer containing the rest of the response from the IMAP
 * server. (If @ret was passed but there was no extended response, @ret will
 * be set to NULL.) The caller function is responsible for freeing @ret.
 * 
 * This camel method gets the additional data returned by "multi-line" IMAP
 * commands, such as SELECT, LIST, FETCH, and various other commands.
 * The returned data is un-byte-stuffed, and has lines termined by
 * newlines rather than CR/LF pairs.
 * 
 * Return value: one of CAMEL_IMAP_OK (command executed successfully),
 * CAMEL_IMAP_NO (operational error message), CAMEL_IMAP_BAD (error
 * message from the server), or CAMEL_IMAP_FAIL (a protocol-level error
 * occurred, and Camel is uncertain of the result of the command.)
 **/
gint
camel_imap_command_extended (CamelImapStore *store, CamelFolder *folder, char **ret, char *fmt, ...)
{
    CamelService *service = CAMEL_SERVICE (store);
    CamelURL *url = service->url;
    gint len = 0, recent = 0, status = CAMEL_IMAP_OK;
    gchar *cmdid, *cmdbuf, *respbuf;
    GPtrArray *data;
    va_list app;
    int i;
    
#if 0   
    /* First make sure we're connected... */
    if (!service->connected || !stream_is_alive (store->istream)) {
        CamelException *ex;
        
        ex = camel_exception_new ();
        
        if (!imap_disconnect (service, ex) || !imap_connect (service, ex)) {
            camel_exception_free (ex);
            
            *ret = NULL;
            
            return CAMEL_IMAP_FAIL;
        }
        service->connected = TRUE;
        
        camel_exception_free (ex);
    }
#endif  
    
    if (folder && store->current_folder != folder && strncmp (fmt, "CREATE", 6)) {
        /* We need to select the correct mailbox first */
        char *r, *folder_path, *dir_sep;
        int s;
        
        dir_sep = store->dir_sep;
        
        if (url && url->path && *(url->path + 1) && strcmp (folder->full_name, "INBOX"))
            folder_path = g_strdup_printf ("%s%s%s", url->path + 1, dir_sep, folder->full_name);
        else
            folder_path = g_strdup (folder->full_name);
        
        s = camel_imap_command_extended (store, NULL, &r, "SELECT %s", folder_path);
        g_free (folder_path);
        if (!r || s != CAMEL_IMAP_OK) {
            *ret = r;
            store->current_folder = NULL;
            
            return s;
        }
        
        g_free (r);
        
        store->current_folder = folder;
    }
    
    /* Create the command */
    cmdid = g_strdup_printf ("A%.5d", store->command++);
    va_start (app, fmt);
    cmdbuf = g_strdup_vprintf (fmt, app);
    va_end (app);
    
    d(fprintf (stderr, "sending : %s %s\r\n", cmdid, cmdbuf));
    
    if (camel_stream_printf (store->ostream, "%s %s\r\n", cmdid, cmdbuf) == -1) {
        g_free (cmdbuf);
        g_free (cmdid);
        
        *ret = g_strdup (strerror (errno));
        
        return CAMEL_IMAP_FAIL;
    }
    g_free (cmdbuf);
    
    data = g_ptr_array_new ();
    
    while (1) {
        CamelStreamBuffer *stream = CAMEL_STREAM_BUFFER (store->istream);
        char *ptr;
        
        respbuf = camel_stream_buffer_read_line (stream);
        if (!respbuf || !strncmp (respbuf, cmdid, strlen (cmdid))) {
            /* IMAP's last response starts with our command id */
            d(fprintf (stderr, "received: %s\n", respbuf ? respbuf : "(null)"));
#if 0           
            if (!respbuf && strcmp (fmt, "LOGOUT")) {
                /* we need to force a disconnect here? */
                CamelException *ex;
                
                ex = camel_exception_new ();
                imap_disconnect (service, ex);
                camel_exception_free (ex);
                }
#endif  
            break;
        }
        
        d(fprintf (stderr, "received: %s\n", respbuf));
        
        g_ptr_array_add (data, respbuf);
        len += strlen (respbuf) + 1;
        
        /* If recent was somehow set and this response doesn't begin with a '*'
           then recent must have been misdetected */
        if (recent && *respbuf != '*')
            recent = 0;
        
        if (*respbuf == '*' && (ptr = strstr (respbuf, "RECENT"))) {
            char *rcnt;
            
            d(fprintf (stderr, "*** We may have found a 'RECENT' flag: %s\n", respbuf));
            /* Make sure it's in the form: "* %d RECENT" */
            rcnt = imap_next_word (respbuf);
            if (*rcnt >= '0' && *rcnt <= '9' && !strncmp ("RECENT", imap_next_word (rcnt), 6))
                recent = atoi (rcnt);
        }
    }
    
    if (respbuf) {
        g_ptr_array_add (data, respbuf);
        len += strlen (respbuf) + 1;
        
        status = camel_imap_status (cmdid, respbuf);
    } else {
        status = CAMEL_IMAP_FAIL;
    }
    g_free (cmdid);
    
    if (status == CAMEL_IMAP_OK) {
        char *p;
        
        *ret = g_malloc0 (len + 1);
        
        for (i = 0, p = *ret; i < data->len; i++) {
            char *ptr, *datap;
            
            datap = (char *) data->pdata[i];
            ptr = (*datap == '.') ? datap + 1 : datap;
            len = strlen (ptr);
            memcpy (p, ptr, len);
            p += len;
            *p++ = '\n';
        }
        *p = '\0';
    } else {
        if (status != CAMEL_IMAP_FAIL && respbuf) {
            char *word;

            word = imap_next_word (respbuf); /* word should now point to NO or BAD */
            
            *ret = g_strdup (imap_next_word (word));
        } else {
            *ret = NULL;
        }
    }
    
    for (i = 0; i < data->len; i++)
        g_free (data->pdata[i]);
    g_ptr_array_free (data, TRUE);
    
    if (folder && recent > 0) {
        CamelException *ex;
        
        ex = camel_exception_new ();
        camel_imap_folder_changed (folder, recent, ex);
        camel_exception_free (ex);
    }
    
    return status;
}