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

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; fill-column: 160 -*- */
/* camel-imap-folder.c : Abstract class for an email folder */

/* 
 * Authors: Jeffrey Stedfast <fejj@helixcode.com> 
 *
 * Copyright (C) 2000 Helix Code, Inc.
 *
 * 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 Place, Suite 330, Boston, MA 02111-1307
 * USA
 */


#include <config.h> 

#include <stdlib.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>

#include "camel-imap-folder.h"
#include "camel-imap-store.h"
#include "string-utils.h"
#include "camel-stream.h"
#include "camel-stream-fs.h"
#include "camel-stream-mem.h"
#include "camel-stream-buffer.h"
#include "camel-data-wrapper.h"
#include "camel-mime-message.h"
#include "camel-stream-filter.h"
#include "camel-mime-filter-from.h"
#include "camel-exception.h"

#define d(x)

static CamelFolderClass *parent_class = NULL;

static void imap_init (CamelFolder *folder, CamelStore *parent_store,
               CamelFolder *parent_folder, const gchar *name,
               gchar separator, CamelException *ex);

static void imap_open (CamelFolder *folder, CamelFolderOpenMode mode, CamelException *ex);
static void imap_close (CamelFolder *folder, gboolean expunge, CamelException *ex);
static gboolean imap_exists (CamelFolder *folder, CamelException *ex);
static gboolean imap_create(CamelFolder *folder, CamelException *ex);
static gboolean imap_delete (CamelFolder *folder, gboolean recurse, CamelException *ex);
static gboolean imap_delete_messages (CamelFolder *folder, CamelException *ex);
static gint imap_get_message_count (CamelFolder *folder, CamelException *ex);
static void imap_append_message (CamelFolder *folder, CamelMimeMessage *message, CamelException *ex);
static GPtrArray *imap_get_uids (CamelFolder *folder, CamelException *ex);
static GPtrArray *imap_get_subfolder_names (CamelFolder *folder, CamelException *ex);
static GPtrArray *imap_get_summary (CamelFolder *folder, CamelException *ex);
static void imap_free_summary (CamelFolder *folder, GPtrArray *array);
static CamelMimeMessage *imap_get_message_by_uid (CamelFolder *folder, const gchar *uid, 
                          CamelException *ex);

static void imap_expunge (CamelFolder *folder, CamelException *ex);

#if 0
static void _copy_message_to (CamelFolder *folder, CamelMimeMessage *message, 
                  CamelFolder *dest_folder, CamelException *ex);
static const gchar *_get_message_uid (CamelFolder *folder, CamelMimeMessage *message, 
                      CamelException *ex);
#endif

static void imap_delete_message_by_uid(CamelFolder *folder, const gchar *uid, CamelException *ex);

static const CamelMessageInfo *imap_summary_get_by_uid(CamelFolder *f, const char *uid);

static GList *imap_search_by_expression(CamelFolder *folder, const char *expression, CamelException *ex);

static void imap_finalize (GtkObject *object);

static void
camel_imap_folder_class_init (CamelImapFolderClass *camel_imap_folder_class)
{
    CamelFolderClass *camel_folder_class = CAMEL_FOLDER_CLASS (camel_imap_folder_class);
    GtkObjectClass *gtk_object_class = GTK_OBJECT_CLASS (camel_folder_class);

    parent_class = gtk_type_class (camel_folder_get_type ());
        
    /* virtual method definition */

    /* virtual method overload */
    camel_folder_class->init = imap_init;

    camel_folder_class->open = imap_open;
    camel_folder_class->close = imap_close;

    camel_folder_class->exists = imap_exists;
    camel_folder_class->create = imap_create;
    camel_folder_class->delete = imap_delete;

    camel_folder_class->delete_messages = imap_delete_messages;
    camel_folder_class->get_message_count = imap_get_message_count;
    camel_folder_class->append_message = imap_append_message;
    camel_folder_class->get_uids = imap_get_uids;
    camel_folder_class->get_subfolder_names = imap_get_subfolder_names;
    camel_folder_class->get_summary = imap_get_summary;
    camel_folder_class->free_summary = imap_free_summary;
    camel_folder_class->expunge = imap_expunge;

    camel_folder_class->get_message_by_uid = imap_get_message_by_uid;
    camel_folder_class->delete_message_by_uid = imap_delete_message_by_uid;

    camel_folder_class->search_by_expression = imap_search_by_expression;

    camel_folder_class->summary_get_by_uid = imap_summary_get_by_uid;

    gtk_object_class->finalize = imap_finalize; 
}

static void
camel_imap_folder_init (gpointer object, gpointer klass)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (object);
    CamelFolder *folder = CAMEL_FOLDER (object);

    folder->can_hold_messages = TRUE;
    folder->can_hold_folders = TRUE;
    folder->has_summary_capability = FALSE;
    folder->has_search_capability = FALSE;

    imap_folder->count = -1;
}

GtkType
camel_imap_folder_get_type (void)
{
    static GtkType camel_imap_folder_type = 0;
    
    if (!camel_imap_folder_type)    {
        GtkTypeInfo camel_imap_folder_info =    
        {
            "CamelImapFolder",
            sizeof (CamelImapFolder),
            sizeof (CamelImapFolderClass),
            (GtkClassInitFunc) camel_imap_folder_class_init,
            (GtkObjectInitFunc) NULL,
                /* reserved_1 */ NULL,
                /* reserved_2 */ NULL,
            (GtkClassInitFunc) NULL,
        };
        
        camel_imap_folder_type = gtk_type_unique (CAMEL_FOLDER_TYPE, &camel_imap_folder_info);
    }
    
    return camel_imap_folder_type;
}

CamelFolder *
camel_imap_folder_new (CamelStore *parent, CamelException *ex)
{
    /* TODO: code this - do we need this? */
    CamelFolder *folder = CAMEL_FOLDER (gtk_object_new (camel_imap_folder_get_type (), NULL));

    CAMEL_FOLDER_CLASS (folder)->init (folder, parent, NULL, "inbox", '/', ex);
    return folder;
}

static void           
imap_finalize (GtkObject *object)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (object);

    g_free (imap_folder->folder_file_path);
    g_free (imap_folder->folder_dir_path);

    GTK_OBJECT_CLASS (parent_class)->finalize (object);
}

static void 
imap_init (CamelFolder *folder, CamelStore *parent_store, CamelFolder *parent_folder,
       const gchar *name, gchar separator, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    const gchar *root_dir_path;
    
    /* call parent method */
    parent_class->init (folder, parent_store, parent_folder, name, separator, ex);
    if (camel_exception_get_id (ex))
        return;

    /* we assume that the parent init
       method checks for the existance of @folder */
    folder->can_hold_messages = TRUE;
    folder->can_hold_folders = TRUE;
    folder->has_summary_capability = FALSE;  /* TODO: double-check this */
    folder->has_search_capability = TRUE;    /* This is really a "maybe" */

    
        /* some IMAP daemons support user-flags           *
     * I would not, however, rely on this feature as  *
     * most IMAP daemons are not 100% RFC compliant   */
    folder->permanent_flags = CAMEL_MESSAGE_SEEN |
        CAMEL_MESSAGE_ANSWERED |
        CAMEL_MESSAGE_FLAGGED |
        CAMEL_MESSAGE_DELETED |
        CAMEL_MESSAGE_DRAFT |
        CAMEL_MESSAGE_USER;

    
    imap_folder->summary = NULL;
    imap_folder->search = NULL;

    /* now set the name info */
    g_free (imap_folder->folder_file_path);
    g_free (imap_folder->folder_dir_path);
    g_free (imap_folder->index_file_path);

    root_dir_path = camel_imap_store_get_toplevel_dir (CAMEL_IMAP_STORE(folder->parent_store));

    imap_folder->folder_file_path = g_strdup_printf ("%s/%s", root_dir_path, folder->full_name);
#if 0
    imap_folder->folder_dir_path = g_strdup_printf ("%s/%s.sdb", root_dir_path, folder->full_name);
    imap_folder->index_file_path = g_strdup_printf ("%s/%s.ibex", root_dir_path, folder->full_name);
#endif
}

static void
imap_open (CamelFolder *folder, CamelFolderOpenMode mode, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    gchar *result;
    gint status;

    camel_imap_store_open (CAMEL_IMAP_STORE (folder->parent_store), ex);
    if (camel_exception_get_id (ex) == CAMEL_EXCEPTION_NONE) {
        /* do we actually want to do this? probably not */
        parent_class->open (folder, mode, ex);

        /* SELECT the IMAP mail spool */
        status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), &result,
                              "SELECT %s", imap_folder->folder_file_path);

        if (status != CAMEL_IMAP_OK) {
            CamelService *service = CAMEL_SERVICE (folder->parent_store);
            camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                          "Could not SELECT %s on IMAP server %s: %s.",
                          imap_folder->folder_file_path, 
                          service->url->host, 
                          status == CAMEL_IMAP_ERR ? result :
                          "Unknown error");
            g_free (result);
            return;
        }

        g_free(result);
    }
}

static void
imap_close (CamelFolder *folder, gboolean expunge, CamelException *ex)
{
    /* TODO: actually code this method */
    camel_imap_store_close (CAMEL_IMAP_STORE (folder->parent_store), expunge, ex);
    if (camel_exception_get_id (ex) == CAMEL_EXCEPTION_NONE) 
        parent_class->close (folder, expunge, ex);

    
}

static void
imap_expunge (CamelFolder *folder, CamelException *ex)
{
    /*CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);*/
    gchar *result;
    gint status;

    g_return_if_fail (folder != NULL);
    
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), &result,
                          "EXPUNGE");
    
    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not EXPUNGE from IMAP server %s: %s.",
                      service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return;
    }
    
    g_free(result);
}

static gboolean
imap_exists (CamelFolder *folder, CamelException *ex)
{
    /* make sure the folder exists */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    GPtrArray *lsub;
    gboolean exists = FALSE;
    int i, max;

    g_return_val_if_fail (folder != NULL, FALSE);

    imap_folder = CAMEL_IMAP_FOLDER (folder);

    /* check if the imap file path is determined */
    if (!imap_folder->folder_file_path) {
        camel_exception_set (ex, CAMEL_EXCEPTION_FOLDER_INVALID,
                     "undetermined folder file path. Maybe use set_name ?");
        return FALSE;
    }

    /* check if the imap dir path is determined */
    if (!imap_folder->folder_dir_path) {
        camel_exception_set (ex, CAMEL_EXCEPTION_FOLDER_INVALID,
                     "undetermined folder directory path. Maybe use set_name ?");
        return FALSE;
    }

    /* Get a listing of the folders that exist */
    lsub = imap_get_subfolder_names (folder, ex);

    /* look to see if any of those subfolders match... */
    max = lsub->len;
    for (i = 0; i < max; i++)
        if (!strcmp(g_ptr_array_index(lsub, i), imap_folder->folder_file_path))
        {
            exists = TRUE;
            break;
        }

    g_ptr_array_free (lsub, TRUE);

    return exists;
}

static gboolean
imap_create (CamelFolder *folder, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    const gchar *folder_file_path, *folder_dir_path;
    gboolean folder_already_exists;
    gchar *result;
    gint status;

    g_return_val_if_fail (folder != NULL, FALSE);

    /* call default implementation */
    parent_class->create (folder, ex);
    if (camel_exception_get_id (ex))
        return FALSE;
    
    /* get the paths of what we need to create */
    folder_file_path = imap_folder->folder_file_path;
    folder_dir_path = imap_folder->folder_dir_path;
    
    if (!(folder_file_path || folder_dir_path)) {
        camel_exception_set (ex, CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }
    
    /* if the folder already exists, simply return */
    folder_already_exists = camel_folder_exists (folder, ex);
    if (camel_exception_get_id (ex))
        return FALSE;

    if (folder_already_exists)
        return TRUE;

    /* create the directory for the subfolder */
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), &result,
                          "CREATE %s", imap_folder->folder_file_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.",
                      imap_folder->folder_file_path,
                      service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return FALSE;
    }
    
    g_free(result);

    return TRUE;
}

static gboolean
imap_delete (CamelFolder *folder, gboolean recurse, CamelException *ex)
{
    /* TODO: code this & what should this do? delete messages or the folder? */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    const gchar *folder_file_path, *folder_dir_path;
    gboolean folder_already_exists;

    g_return_val_if_fail (folder != NULL, FALSE);

    /* check if the folder object exists */

    /* in the case where the folder does not exist, 
       return immediatly */
    folder_already_exists = camel_folder_exists (folder, ex);
    if (camel_exception_get_id (ex))
        return FALSE;

    if (!folder_already_exists)
        return TRUE;


    /* call default implementation.
       It should delete the messages in the folder
       and recurse the operation to subfolders */
    parent_class->delete (folder, recurse, ex);
    if (camel_exception_get_id (ex))
        return FALSE;

    /* get the paths of what we need to be deleted */
    folder_file_path = imap_folder->folder_file_path;
    folder_dir_path = imap_folder->folder_file_path;
    
    if (!(folder_file_path || folder_dir_path)) {
        camel_exception_set (ex, CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }
    
        /* delete the directory - we must start with the leaves and work
       back to the root if we are to delete recursively */

    /* TODO: Finish this... */

    return TRUE;
}

/* TODO: remove this - don't bother coding, it'll be moved/removed */
gboolean
imap_delete_messages (CamelFolder *folder, CamelException *ex)
{
    /* TODO: delete the messages (mark as deleted/whatever) */
#if 0
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    gchar *result;
    gint status;
#endif

    g_return_val_if_fail (folder != NULL, FALSE);

    return TRUE;
}

static gint
imap_get_message_count (CamelFolder *folder, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    gchar *result, *msg_count;
    gint status;

    g_return_val_if_fail (folder != NULL, -1);

    /* If we already have a count, return */
    if (imap_folder->count != -1)
        return imap_folder->count;

    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), &result,
                          "STATUS %s (MESSAGES)", imap_folder->folder_file_path);

    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not get message count from IMAP "
                      "server %s: %s.", service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return -1;
    }

    /* parse out the message count - should come in the form: "* STATUS <folder> (MESSAGES <count>)\r\n" */
    if (result && *result == '*') {
        if ((msg_count = strstr(result, "MESSAGES")) != NULL) {
            msg_count += strlen("MESSAGES") + 1;

            for ( ; *msg_count == ' '; msg_count++);
            
            /* we should now be pointing to the message count */
            imap_folder->count = atoi(msg_count);
        }
    }
    g_free(result);

    return imap_folder->count;
}

/* TODO: Optimize this later - there may be times when moving/copying a message from the
   same IMAP store in which case we'd want to use IMAP's COPY command */
static void
imap_append_message (CamelFolder *folder, CamelMimeMessage *message, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    CamelStreamMem *mem;
    gchar *result;
    gint status;

    g_return_if_fail (folder != NULL);
    g_return_if_fail (message != NULL);

    /* write the message to a CamelStreamMem so we can get it's size */
    mem = camel_stream_mem_new();
    if (camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (message), CAMEL_STREAM (mem)) == -1) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "Could not APPEND message to IMAP server %s: %s.",
                      service->url->host,
                      g_strerror (errno));

            return;
    }

    mem->buffer = g_byte_array_append(mem->buffer, g_strdup("\n"), 2);
    status = camel_imap_command(CAMEL_IMAP_STORE (folder->parent_store),
                    &result,
                    "APPEND %s (\\Seen) {%d}\r\n%s",
                    imap_folder->folder_file_path,
                    mem->buffer->len,
                    mem->buffer->data);

    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not APPEND message to IMAP server %s: %s.",
                      service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return;
    }

    g_free(result);
    return;
}

static GPtrArray *
imap_get_uids (CamelFolder *folder, CamelException *ex) 
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    CamelImapMessageInfo *info;
    GPtrArray *array;
    gint i, count;

    count = camel_folder_summary_count(CAMEL_FOLDER_SUMMARY (imap_folder->summary));
    array = g_ptr_array_new ();
    g_ptr_array_set_size (array, count);
    for (i = 0; i < count; i++) {
        info = CAMEL_IMAP_MESSAGE_INFO (camel_folder_summary_index(CAMEL_FOLDER_SUMMARY (imap_folder->summary), i));
        array->pdata[i] = g_strdup(info->info.uid);
    }
    
    return array;
}

static GPtrArray *
imap_get_subfolder_names (CamelFolder *folder, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    GPtrArray *listing;
    gint status;
    gchar *result;
    
    g_return_val_if_fail (folder != NULL, g_ptr_array_new());
    
    if (imap_folder->count != -1)
        return g_ptr_array_new ();
    
    status = camel_imap_command_extended (CAMEL_IMAP_STORE (folder->parent_store), &result,
                          "LSUB \"\" \"%s\"", imap_folder->folder_file_path);
    
    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not get subfolder listing from IMAP "
                      "server %s: %s.", service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return g_ptr_array_new ();
    }
    
    /* parse out the subfolders */
    listing = g_ptr_array_new ();
    g_ptr_array_add(listing, g_strdup("INBOX"));
    if (result) {
        char *ptr = result;
        
        while (*ptr == '*') {
            gchar *flags, *end, *dir_sep, *param = NULL;
            
            ptr = flags = strchr(ptr, '(') + 1;    /* jump to the flags section */
            end = strchr(flags, ')');              /* locate end of flags */
            flags = g_strndup(flags, (gint)(end - flags));
            
            if (strstr(flags, "\\NoSelect")) {
                g_free(flags);
                continue;
            }
            g_free(flags);

            ptr = dir_sep = strchr(ptr, '"') + 1;  /* jump to the first param */
            end = strchr(param, '"');              /* locate the end of the param */
            dir_sep = g_strndup(dir_sep, (gint)(end - param));

            /* skip to the actual directory parameter */
            for (ptr = end++; *ptr == ' '; ptr++);
                        for (end = ptr; *end && *end != '\n'; end++);
            param = g_strndup(ptr, (gint)(end - ptr));

            g_ptr_array_add(listing, param);

            g_free(dir_sep);  /* TODO: decide if we really need dir_sep */

            if (*end)
                ptr = end + 1;
            else
                ptr = end;
        }
    }
    g_free(result);

    return listing;
}

static void
imap_delete_message_by_uid (CamelFolder *folder, const gchar *uid, CamelException *ex)
{
    /*CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);*/
    gchar *result;
    gint status;

    status = camel_imap_command_extended(CAMEL_IMAP_STORE (folder->parent_store),
                         &result, "UID STORE %s +FLAGS.SILENT (\\Deleted)", uid);

    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not mark message %s as 'Deleted' on IMAP server %s: %s",
                      uid, service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return;
    }

    g_free (result);
    return;
}

/* track flag changes in the summary */
static void
message_changed (CamelMimeMessage *m, int type, CamelImapFolder *mf)
{
    CamelMessageInfo *info;
    CamelFlag *flag;

    printf("Message changed: %s: %d\n", m->message_uid, type);
    switch (type) {
    case MESSAGE_FLAGS_CHANGED:
        info = camel_folder_summary_uid(CAMEL_FOLDER_SUMMARY (mf->summary), m->message_uid);
        if (info) {
            info->flags = m->flags | CAMEL_MESSAGE_FOLDER_FLAGGED;
            camel_flag_list_free(&info->user_flags);
            flag = m->user_flags;
            while (flag) {
                camel_flag_set(&info->user_flags, flag->name, TRUE);
                flag = flag->next;
            }
            camel_folder_summary_touch(CAMEL_FOLDER_SUMMARY (mf->summary));
        } else
            g_warning("Message changed event on message not in summary: %s", m->message_uid);
        break;
    default:
        printf("Unhandled message change event: %d\n", type);
        break;
    }
}

static CamelMimeMessage *
imap_get_message_by_uid (CamelFolder *folder, const gchar *uid, CamelException *ex)
{
    /* NOTE: extremely easy to do in IMAP - just needa code it ;-) */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    CamelStreamMem *message_stream = NULL;
    CamelMimeMessage *message = NULL;
    CamelImapMessageInfo *info;
    CamelMimeParser *parser = NULL;
    gchar *buffer, *result;
    gint len, status;

    /* get the message summary info */
    info = (CamelImapMessageInfo *)camel_folder_summary_uid(CAMEL_FOLDER_SUMMARY (imap_folder->summary), uid);

    if (info == NULL) {
        errno = ENOENT;
        goto fail;
    }

    /* if this has no content, its an error in the library */
    g_assert(info->info.content);
    g_assert(info->frompos != -1);

    /* get our message buffer */
    status = camel_imap_command_extended(CAMEL_IMAP_STORE (folder->parent_store),
                         &result, "UID FETCH %s (FLAGS BODY[])", uid);

    if (status != CAMEL_IMAP_OK) {
        CamelService *service = CAMEL_SERVICE (folder->parent_store);
        
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      "Could not mark message %s as 'Deleted' on IMAP server %s: %s",
                      uid, service->url->host,
                      status == CAMEL_IMAP_ERR ? result :
                      "Unknown error");
        g_free (result);
        return;
    }
    
    /* where we read from */
    message_stream = camel_stream_mem_new_with_buffer (result, strlen(result));
    if (message_stream == NULL)
        goto fail;

    /* we use a parser to verify the message is correct, and in the correct position */
    parser = camel_mime_parser_new();
    camel_mime_parser_init_with_stream(parser, message_stream);
    gtk_object_unref(GTK_OBJECT (message_stream));
    camel_mime_parser_scan_from(parser, TRUE);

    camel_mime_parser_seek(parser, info->frompos, SEEK_SET);
    if (camel_mime_parser_step(parser, &buffer, &len) != HSCAN_FROM) {
        g_warning("File appears truncated");
        goto fail;
    }

    if (camel_mime_parser_tell_start_from(parser) != info->frompos) {
        g_warning("Summary doesn't match the folder contents!  eek!"
              "  expecting offset %ld got %ld", (long int)info->frompos,
              (long int)camel_mime_parser_tell_start_from(parser));
        errno = EINVAL;
        goto fail;
    }

    message = camel_mime_message_new();
    if (camel_mime_part_construct_from_parser(CAMEL_MIME_PART (message), parser) == -1) {
        g_warning("Construction failed");
        goto fail;
    }

    /* we're constructed, finish setup and clean up */
    message->folder = folder;
    gtk_object_ref(GTK_OBJECT (folder));
    message->message_uid = g_strdup(uid);
    message->flags = info->info.flags;
    gtk_signal_connect(GTK_OBJECT (message), "message_changed", message_changed, folder);

    gtk_object_unref(GTK_OBJECT (parser));

    return message;

 fail:
    camel_exception_setv (ex, CAMEL_EXCEPTION_FOLDER_INVALID_UID,
                  "Cannot get message: %s",
                  g_strerror(errno));

    if (parser)
        gtk_object_unref(GTK_OBJECT (parser));
    if (message)
        gtk_object_unref(GTK_OBJECT (message));

    return NULL;
}

GPtrArray *
imap_get_summary (CamelFolder *folder, CamelException *ex)
{
    /* TODO: what should we do here?? */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);

    return CAMEL_FOLDER_SUMMARY (imap_folder->summary)->messages;
}

void
imap_free_summary (CamelFolder *folder, GPtrArray *array)
{
    /* no-op */
    return;
}

/* get a single message info, by uid */
static const CamelMessageInfo *
imap_summary_get_by_uid (CamelFolder *f, const char *uid)
{
    /* TODO: what do we do here? */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (f);

    return camel_folder_summary_uid(CAMEL_FOLDER_SUMMARY (imap_folder->summary), uid);
}

static GList *
imap_search_by_expression (CamelFolder *folder, const char *expression, CamelException *ex)
{
    /* TODO: find a good way of doing this */
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);

    if (imap_folder->search == NULL) {
        imap_folder->search = camel_folder_search_new();
    }

    camel_folder_search_set_folder(imap_folder->search, folder);
    if (imap_folder->summary)
        /* FIXME: dont access summary array directly? */
        camel_folder_search_set_summary(imap_folder->search,
                        CAMEL_FOLDER_SUMMARY (imap_folder->summary)->messages);
    camel_folder_search_set_body_index(imap_folder->search, imap_folder->index);

    return camel_folder_search_execute_expression(imap_folder->search, expression, ex);
}