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

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-imap-folder.c: class for an imap 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 <ctype.h>

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

#include "camel-imap-folder.h"
#include "camel-imap-command.h"
#include "camel-imap-search.h"
#include "camel-imap-store.h"
#include "camel-imap-summary.h"
#include "camel-imap-utils.h"
#include "camel-imap-wrapper.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-mime-filter-crlf.h"
#include "camel-exception.h"
#include "camel-mime-utils.h"
#include "camel-imap-private.h"
#include "camel-multipart.h"

#define d(x) x

#define CF_CLASS(o) (CAMEL_FOLDER_CLASS (CAMEL_OBJECT_GET_CLASS(o)))

static CamelFolderClass *parent_class = NULL;

static void imap_finalize (CamelObject *object);
static void imap_rescan (CamelFolder *folder, int exists, CamelException *ex);
static void imap_refresh_info (CamelFolder *folder, CamelException *ex);
static void imap_sync (CamelFolder *folder, gboolean expunge, CamelException *ex);
static const char *imap_get_full_name (CamelFolder *folder);
static void imap_expunge (CamelFolder *folder, CamelException *ex);

/* message manipulation */
static CamelMimeMessage *imap_get_message (CamelFolder *folder, const gchar *uid,
                       CamelException *ex);
static void imap_append_message (CamelFolder *folder, CamelMimeMessage *message,
                 const CamelMessageInfo *info, CamelException *ex);
static void imap_copy_message_to (CamelFolder *source, const char *uid,
                  CamelFolder *destination, CamelException *ex);
static void imap_move_message_to (CamelFolder *source, const char *uid,
                  CamelFolder *destination, CamelException *ex);

/* summary info */
static void imap_update_summary (CamelFolder *folder, int first, int last,
                 CamelFolderChangeInfo *changes,
                 CamelException *ex);

/* searching */
static GPtrArray *imap_search_by_expression (CamelFolder *folder, const char *expression, CamelException *ex);
static void       imap_search_free          (CamelFolder *folder, GPtrArray *uids);

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

    parent_class = CAMEL_FOLDER_CLASS(camel_type_get_global_classfuncs (camel_folder_get_type ()));
    
    /* virtual method definition */
    
    /* virtual method overload */
    camel_folder_class->refresh_info = imap_refresh_info;
    camel_folder_class->sync = imap_sync;
    camel_folder_class->expunge = imap_expunge;
    camel_folder_class->get_full_name = imap_get_full_name;
    
    camel_folder_class->get_message = imap_get_message;
    camel_folder_class->append_message = imap_append_message;
    camel_folder_class->copy_message_to = imap_copy_message_to;
    camel_folder_class->move_message_to = imap_move_message_to;
    
    camel_folder_class->search_by_expression = imap_search_by_expression;
    camel_folder_class->search_free = imap_search_free;
}

static void
camel_imap_folder_init (gpointer object, gpointer klass)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (object);
    CamelFolder *folder = CAMEL_FOLDER (object);
    
    folder->has_summary_capability = TRUE;
    folder->has_search_capability = TRUE;
    
    imap_folder->priv = g_malloc0(sizeof(*imap_folder->priv));
#ifdef ENABLE_THREADS
    imap_folder->priv->search_lock = g_mutex_new();
#endif
}

CamelType
camel_imap_folder_get_type (void)
{
    static CamelType camel_imap_folder_type = CAMEL_INVALID_TYPE;
    
    if (camel_imap_folder_type == CAMEL_INVALID_TYPE) {
        camel_imap_folder_type =
            camel_type_register (CAMEL_FOLDER_TYPE, "CamelImapFolder",
                         sizeof (CamelImapFolder),
                         sizeof (CamelImapFolderClass),
                         (CamelObjectClassInitFunc) camel_imap_folder_class_init,
                         NULL,
                         (CamelObjectInitFunc) camel_imap_folder_init,
                         (CamelObjectFinalizeFunc) imap_finalize);
    }
    
    return camel_imap_folder_type;
}

CamelFolder *
camel_imap_folder_new (CamelStore *parent, const char *folder_name,
               const char *short_name, const char *summary_file,
               CamelException *ex)
{
    CamelImapStore *imap_store = CAMEL_IMAP_STORE (parent);
    CamelFolder *folder = CAMEL_FOLDER (camel_object_new (camel_imap_folder_get_type ()));
    CamelImapResponse *response;
    char *resp;
    guint32 validity = 0;
    int i, exists = 0;

    camel_folder_construct (folder, parent, folder_name, short_name);

    CAMEL_IMAP_STORE_LOCK(imap_store, command_lock);
    response = camel_imap_command (imap_store, folder, ex, NULL);
    CAMEL_IMAP_STORE_UNLOCK(imap_store, command_lock);

    if (!response) {
        camel_object_unref ((CamelObject *)folder);
        return NULL;
    }

    for (i = 0; i < response->untagged->len; i++) {
        resp = response->untagged->pdata[i] + 2;
        if (!g_strncasecmp (resp, "FLAGS ", 6)) {
            resp += 6;
            folder->permanent_flags = imap_parse_flag_list (&resp);
        } else if (!g_strncasecmp (resp, "OK [PERMANENTFLAGS ", 19)) {
            resp += 19;
            folder->permanent_flags = imap_parse_flag_list (&resp);
        } else if (!g_strncasecmp (resp, "OK [UIDVALIDITY ", 16)) {
            validity = strtoul (resp + 16, NULL, 10);
        } else if (isdigit ((unsigned char)*resp)) {
            unsigned long num = strtoul (resp, &resp, 10);

            if (!g_strncasecmp (resp, " EXISTS", 7))
                exists = num;
        }
    }
    camel_imap_response_free (response);

    folder->summary = camel_imap_summary_new (summary_file, validity);
    if (!folder->summary) {
        camel_object_unref (CAMEL_OBJECT (folder));
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Could not load summary for %s"),
                      folder_name);
        return NULL;
    }

    CAMEL_IMAP_STORE_LOCK(imap_store, command_lock);
    imap_rescan (folder, exists, ex);
    CAMEL_IMAP_STORE_UNLOCK(imap_store, command_lock);
    if (camel_exception_is_set (ex)) {
        camel_object_unref (CAMEL_OBJECT (folder));
        return NULL;
    }

    return folder;
}

/* Called with the store's command_lock locked */
void
camel_imap_folder_selected (CamelFolder *folder, CamelImapResponse *response,
                CamelException *ex)
{
    unsigned long exists = 0, val, uid;
    CamelMessageInfo *info;
    int i, count;
    char *resp;

    for (i = 0; i < response->untagged->len; i++) {
        resp = response->untagged->pdata[i] + 2;

        exists = strtoul (resp, &resp, 10);
        if (!g_strncasecmp (resp, " EXISTS", 7))
            break;
    }
    if (i == response->untagged->len) {
        g_warning ("Server response did not include EXISTS info");
        return;
    }

    count = camel_folder_summary_count (folder->summary);

    /* If we've lost messages, we have to rescan everything */
    if (exists < count) {
        imap_rescan (folder, exists, ex);
        return;
    }

    if (count != 0) {
        /* Similarly, if the UID of the highest message we
         * know about has changed, then that indicates that
         * messages have been both added and removed, so we
         * have to rescan to find the removed ones. (We pass
         * NULL for the folder since we know that this folder
         * is selected, and we don't want camel_imap_command
         * to worry about it.)
         */
        response = camel_imap_command (CAMEL_IMAP_STORE (folder->parent_store),
                           NULL, ex, "FETCH %d UID", count);
        if (!response)
            return;
        uid = 0;
        for (i = 0; i < response->untagged->len; i++) {
            resp = response->untagged->pdata[i];
            val = strtoul (resp + 2, &resp, 10);
            if (val != count || g_strncasecmp (resp, " FETCH (", 8) != 0)
                continue;
            resp = e_strstrcase (resp, "UID ");
            if (!resp)
                continue;
            uid = strtoul (resp + 4, NULL, 10);
            break;
        }
        camel_imap_response_free (response);

        info = camel_folder_summary_index (folder->summary, count - 1);
        val = strtoul (camel_message_info_uid (info), NULL, 10);
        camel_folder_summary_info_free (folder->summary, info);
        if (uid == 0 || uid != val) {
            imap_rescan (folder, exists, ex);
            return;
        }
    }

    /* OK. So now we know that no messages have been expunged. Whew.
     * Now see if messages have been added.
     */
    if (exists > count)
        camel_imap_folder_changed (folder, exists, NULL, ex);

    /* And we're done. */
}   

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

    if (imap_folder->search)
        camel_object_unref ((CamelObject *)imap_folder->search);

#ifdef ENABLE_THREADS
    g_mutex_free(imap_folder->priv->search_lock);
#endif
    g_free(imap_folder->priv);
}

static void
imap_refresh_info (CamelFolder *folder, CamelException *ex)
{
    CAMEL_IMAP_STORE_LOCK (folder->parent_store, command_lock);
    imap_rescan (folder, camel_folder_summary_count (folder->summary), ex);
    CAMEL_IMAP_STORE_UNLOCK (folder->parent_store, command_lock);
}

/* Called with the store's command_lock locked */
static void
imap_rescan (CamelFolder *folder, int exists, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelImapResponse *response;
    struct {
        char *uid;
        guint32 flags;
    } *new = NULL;
    char *resp, *p, *flags;
    const char *uid;
    int i, j, seq, summary_len;
    CamelMessageInfo *info;
    CamelImapMessageInfo *iinfo;
    GArray *removed;

    /* Get UIDs and flags of all messages. */
    if (exists > 0) {
        response = camel_imap_command (store, folder, ex,
                           "FETCH 1:%d (UID FLAGS)",
                           exists);
        if (!response)
            return;

        new = g_malloc0 (exists * sizeof (*new));
        for (i = 0; i < response->untagged->len; i++) {
            resp = response->untagged->pdata[i];

            seq = strtoul (resp + 2, &resp, 10);
            if (g_strncasecmp (resp, " FETCH ", 7) != 0)
                continue;

            uid = e_strstrcase (resp, "UID ");
            if (uid) {
                uid += 4;
                strtoul (uid, &p, 10);
                new[seq - 1].uid = g_strndup (uid, p - uid);
            }

            flags = e_strstrcase (resp, "FLAGS ");
            if (flags) {
                flags += 6;
                new[seq - 1].flags = imap_parse_flag_list (&flags);
            }
        }
        camel_imap_response_free (response);
    }

    /* If we find a UID in the summary that doesn't correspond to
     * the UID in the folder, that it means the message was
     * deleted on the server, so we remove it from the summary.
     */
    removed = g_array_new (FALSE, FALSE, sizeof (int));
    summary_len = camel_folder_summary_count (folder->summary);
    for (i = 0; i < summary_len && i < exists; i++) {
        /* Shouldn't happen, but... */
        if (!new[i].uid)
            continue;

        info = camel_folder_summary_index (folder->summary, i);
        iinfo = (CamelImapMessageInfo *)info;

        if (strcmp (camel_message_info_uid (info), new[i].uid) != 0) {
            seq = i + 1;
            g_array_append_val (removed, seq);
            i--;
            summary_len--;
            continue;
        }

        /* Update summary flags */
        if (new[i].flags != iinfo->server_flags) {
            guint32 server_set, server_cleared;

            server_set = new[i].flags & ~iinfo->server_flags;
            server_cleared = iinfo->server_flags & ~new[i].flags;

            info->flags = (info->flags | server_set) & ~server_cleared;
            iinfo->server_flags = new[i].flags;

            camel_object_trigger_event (CAMEL_OBJECT (folder),
                            "message_changed",
                            g_strdup (new[i].uid));
        }

        camel_folder_summary_info_free(folder->summary, info);

        g_free (new[i].uid);
    }

    /* Remove any leftover cached summary messages. */
    for (j = i + 1; j < summary_len; j++) {
        seq = j - removed->len;
        g_array_append_val (removed, seq);
    }

    /* Free remaining memory. */
    while (i < exists)
        g_free (new[i++].uid);
    g_free (new);

    /* And finally update the summary. */
    camel_imap_folder_changed (folder, exists, removed, ex);
    g_array_free (removed, TRUE);
}

static void
sync_message (CamelImapStore *store, CamelFolder *folder,
          CamelMessageInfo *mi, CamelException *ex)
{
    CamelImapResponse *response;
    char *flags;

    flags = imap_create_flag_list (mi->flags);
    CAMEL_IMAP_STORE_LOCK (store, command_lock);
    response = camel_imap_command (store, folder, ex,
                       "UID STORE %s FLAGS.SILENT %s",
                       camel_message_info_uid (mi), flags);
    CAMEL_IMAP_STORE_UNLOCK (store, command_lock);
    g_free (flags);
    if (camel_exception_is_set (ex))
        return;
    camel_imap_response_free (response);

    mi->flags &= ~CAMEL_MESSAGE_FOLDER_FLAGGED;
    ((CamelImapMessageInfo *)mi)->server_flags =
        mi->flags & CAMEL_IMAP_SERVER_FLAGS;
}

static void
imap_sync (CamelFolder *folder, gboolean expunge, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelImapResponse *response;
    int i, max;

    /* Set the flags on any messages that have changed this session */
    max = camel_folder_summary_count (folder->summary);
    for (i = 0; i < max; i++) {
        CamelMessageInfo *info;

        info = camel_folder_summary_index (folder->summary, i);
        if (info && (info->flags & CAMEL_MESSAGE_FOLDER_FLAGGED))
            sync_message (store, folder, info, ex);
        camel_folder_summary_info_free(folder->summary, info);

        if (camel_exception_is_set (ex))
            return;
    }

    if (expunge) {
        CAMEL_IMAP_STORE_LOCK(store, command_lock);
        response = camel_imap_command (store, folder, ex, "EXPUNGE");
        CAMEL_IMAP_STORE_UNLOCK(store, command_lock);
        camel_imap_response_free (response);
    }

    camel_folder_summary_save (folder->summary);
}

static void
imap_expunge (CamelFolder *folder, CamelException *ex)
{
    imap_sync (folder, TRUE, ex);
}

static const char *
imap_get_full_name (CamelFolder *folder)
{
    CamelURL *url = ((CamelService *)folder->parent_store)->url;
    int len;

    if (!url->path || !*url->path || !strcmp (url->path, "/"))
        return folder->full_name;
    len = strlen (url->path + 1);
    if (!strncmp (url->path + 1, folder->full_name, len) &&
        strlen (folder->full_name) > len + 1)
        return folder->full_name + len + 1;
    return folder->full_name;
}   

static void
imap_append_message (CamelFolder *folder, CamelMimeMessage *message,
             const CamelMessageInfo *info, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelImapResponse *response;
    CamelStream *memstream;
    CamelMimeFilter *crlf_filter;
    CamelStreamFilter *streamfilter;
    GByteArray *ba;
    char *flagstr, *result;
    
    /* create flag string param */
    if (info && info->flags)
        flagstr = imap_create_flag_list (info->flags);
    else
        flagstr = NULL;

    /* FIXME: We could avoid this if we knew how big the message was. */
    memstream = camel_stream_mem_new ();
    ba = g_byte_array_new ();
    camel_stream_mem_set_byte_array (CAMEL_STREAM_MEM (memstream), ba);

    streamfilter = camel_stream_filter_new_with_stream (memstream);
    crlf_filter = camel_mime_filter_crlf_new (
        CAMEL_MIME_FILTER_CRLF_ENCODE,
        CAMEL_MIME_FILTER_CRLF_MODE_CRLF_ONLY);
    camel_stream_filter_add (streamfilter, crlf_filter);
    camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (message),
                        CAMEL_STREAM (streamfilter));
    camel_object_unref (CAMEL_OBJECT (streamfilter));
    camel_object_unref (CAMEL_OBJECT (crlf_filter));
    camel_object_unref (CAMEL_OBJECT (memstream));

    CAMEL_IMAP_STORE_LOCK(store, command_lock);
    response = camel_imap_command (store, NULL, ex, "APPEND %S%s%s {%d}",
                       folder->full_name, flagstr ? " " : "",
                       flagstr ? flagstr : "", ba->len);
    g_free (flagstr);
    
    if (!response) {
        g_byte_array_free (ba, TRUE);
        CAMEL_IMAP_STORE_UNLOCK(store, command_lock);
        return;
    }
    result = camel_imap_response_extract_continuation (response, ex);
    if (!result) {
        g_byte_array_free (ba, TRUE);
        CAMEL_IMAP_STORE_UNLOCK(store, command_lock);
        return;
    }
    g_free (result);

    /* send the rest of our data - the mime message */
    g_byte_array_append (ba, "\0", 3);
    response = camel_imap_command_continuation (store, ex, ba->data);
    g_byte_array_free (ba, TRUE);
    CAMEL_IMAP_STORE_UNLOCK(store, command_lock);
    if (!response)
        return;
    camel_imap_response_free (response);
}

static void
imap_copy_message_to (CamelFolder *source, const char *uid,
              CamelFolder *destination, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (source->parent_store);
    CamelImapResponse *response;
    CamelMessageInfo *mi;

    mi = camel_folder_summary_uid (source->summary, uid);
    g_return_if_fail (mi != NULL);

    /* Sync message flags if needed. */
    if (mi->flags & CAMEL_MESSAGE_FOLDER_FLAGGED)
        sync_message (store, source, mi, ex);
    camel_folder_summary_info_free (source->summary, mi);

    if (camel_exception_is_set (ex))
        return;

    /* Now copy it */
    CAMEL_IMAP_STORE_LOCK(store, command_lock);
    response = camel_imap_command (store, source, ex, "UID COPY %s %S",
                       uid, destination->full_name);
    CAMEL_IMAP_STORE_UNLOCK(store, command_lock);

    if (camel_exception_is_set (ex))
        return;

    camel_imap_response_free (response);

    /* Force the destination folder to notice its new messages. */
    response = camel_imap_command (store, destination, NULL, "NOOP");
    camel_imap_response_free (response);
 }

static void
imap_move_message_to (CamelFolder *source, const char *uid,
              CamelFolder *destination, CamelException *ex)
{
    imap_copy_message_to (source, uid, destination, ex);
    if (camel_exception_is_set (ex))
        return;

    camel_folder_delete_message (source, uid);
}

static GPtrArray *
imap_search_by_expression (CamelFolder *folder, const char *expression, CamelException *ex)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);
    GPtrArray *matches, *summary;

    /* we could get around this by creating a new search object each time,
       but i doubt its worth it since any long operation would lock the
       command channel too */
    CAMEL_IMAP_FOLDER_LOCK(folder, search_lock);

    if (!imap_folder->search)
        imap_folder->search = camel_imap_search_new ();

    camel_folder_search_set_folder (imap_folder->search, folder);
    summary = camel_folder_get_summary(folder);
    camel_folder_search_set_summary(imap_folder->search, summary);
    matches = camel_folder_search_execute_expression (imap_folder->search, expression, ex);

    CAMEL_IMAP_FOLDER_UNLOCK(folder, search_lock);

    camel_folder_free_summary(folder, summary);

    return matches;
}

static void
imap_search_free (CamelFolder *folder, GPtrArray *uids)
{
    CamelImapFolder *imap_folder = CAMEL_IMAP_FOLDER (folder);

    g_return_if_fail (imap_folder->search);

    CAMEL_IMAP_FOLDER_LOCK(folder, search_lock);

    camel_folder_search_free_result (imap_folder->search, uids);

    CAMEL_IMAP_FOLDER_UNLOCK(folder, search_lock);
}

/* parse a header response (starting after the first ' ' after
 * *@headers_p) and construct a content-free CamelMedium from it.
 */
static CamelMedium *
parse_headers (char **headers_p, CamelType medium_type)
{
    CamelMedium *medium; 
    CamelStream *stream;
    char *headers;
    int len;

    *headers_p = strchr (*headers_p, ' ');
    if (!*headers_p)
        return FALSE;
    (*headers_p)++;

    headers = imap_parse_nstring (headers_p, &len);
    if (!headers)
        return FALSE;
    stream = camel_stream_mem_new_with_buffer (headers, len);
    g_free (headers);

    medium = CAMEL_MEDIUM (camel_object_new (medium_type));
    camel_data_wrapper_construct_from_stream (CAMEL_DATA_WRAPPER (medium), stream);
    camel_object_unref (CAMEL_OBJECT (stream));

    return medium;
}

static CamelMedium *
fetch_medium (CamelFolder *folder, const char *uid, const char *section_text,
          CamelType type, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelImapResponse *response;
    CamelMedium *medium;
    char *result, *p;

    CAMEL_IMAP_STORE_LOCK (store, command_lock);
    if (store->server_level < IMAP_LEVEL_IMAP4REV1 && !*section_text) {
        response = camel_imap_command (store, folder, ex,
                           "UID FETCH %s RFC822.PEEK",
                           uid);
    } else {
        response = camel_imap_command (store, folder, ex,
                           "UID FETCH %s BODY.PEEK[%s]",
                           uid, section_text);
    }
    CAMEL_IMAP_STORE_UNLOCK (store, command_lock);
    if (!response)
        return NULL;

    /* FIXME: there could be multiple lines of FETCH response. */
    result = camel_imap_response_extract (response, "FETCH", ex);
    if (!result)
        return NULL;

    
    if (store->server_level < IMAP_LEVEL_IMAP4REV1 && !*section_text)
        p = e_strstrcase (result, "RFC822");
    else
        p = e_strstrcase (result, "BODY");

    if (p)
        medium = parse_headers (&p, type);
    else {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      _("Could not find message body in FETCH "
                    "response."));
        medium = NULL;
    }
    g_free (result);

    return medium;
}

static CamelMimeMessage *get_message (CamelFolder *folder, const char *uid,
                      const char *part_specifier,
                      CamelMessageContentInfo *ci,
                      CamelException *ex);

/* Fetch the contents of the MIME part indicated by @ci, which is part
 * of message @uid in @folder.
 */
static CamelDataWrapper *
get_content (CamelFolder *folder, const char *uid, const char *part_spec,
         CamelMimePart *part, CamelMessageContentInfo *ci,
         CamelException *ex)
{
    char *child_spec;

    /* There are three cases: multipart, message/rfc822, and "other" */

    if (header_content_type_is (ci->type, "multipart", "*")) {
        CamelMultipart *body_mp;
        CamelDataWrapper *content;
        int speclen, num;

        body_mp = camel_multipart_new ();
        camel_data_wrapper_set_mime_type_field (
            CAMEL_DATA_WRAPPER (body_mp), ci->type);
        camel_multipart_set_boundary (body_mp, NULL);

        speclen = strlen (part_spec);
        child_spec = g_malloc (speclen + 15);
        memcpy (child_spec, part_spec, speclen);
        if (speclen > 0)
            child_spec[speclen++] = '.';

        ci = ci->childs;
        num = 1;
        while (ci) {
            sprintf (child_spec + speclen, "%d.MIME", num++);
            part = (CamelMimePart *)fetch_medium (folder, uid, child_spec, CAMEL_MIME_PART_TYPE, ex);
            *(strchr (child_spec + speclen, '.')) = '\0';
            if (part)
                content = get_content (folder, uid, child_spec, part, ci, ex);
            if (!part || !content) {
                g_free (child_spec);
                camel_object_unref (CAMEL_OBJECT (part));
                camel_object_unref (CAMEL_OBJECT (body_mp));
                return NULL;
            }
            camel_medium_set_content_object (CAMEL_MEDIUM (part),
                             content);
            camel_object_unref (CAMEL_OBJECT (content));
            camel_multipart_add_part (body_mp, part);
            camel_object_unref (CAMEL_OBJECT (part));

            ci = ci->next;
        }
        g_free (child_spec);

        return (CamelDataWrapper *)body_mp;
    } else if (header_content_type_is (ci->type, "message", "rfc822")) {
        return (CamelDataWrapper *)
            get_message (folder, uid, part_spec, ci->childs, ex);
    } else {
        CamelDataWrapper *content;

        if (!ci->parent || header_content_type_is (ci->parent->type, "message", "rfc822"))
            child_spec = g_strdup_printf ("%s%s1", part_spec, *part_spec ? "." : "");
        else
            child_spec = g_strdup (part_spec);
        content = camel_imap_wrapper_new (folder, ci->type, uid, child_spec, part);
        g_free (child_spec);
        return content;
    }
}

static CamelMimeMessage *
get_message (CamelFolder *folder, const char *uid, const char *part_spec,
         CamelMessageContentInfo *ci, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelDataWrapper *content;
    CamelMimeMessage *msg;
    char *section_text;

    section_text = g_strdup_printf ("%s%s%s", part_spec, *part_spec ? "." : "",
                    store->server_level >= IMAP_LEVEL_IMAP4REV1 ? "HEADER" : "0");
    msg = (CamelMimeMessage *)fetch_medium (folder, uid, section_text, CAMEL_MIME_MESSAGE_TYPE, ex);
    g_free (section_text);
    if (!msg)
        return NULL;

    content = get_content (folder, uid, part_spec, CAMEL_MIME_PART (msg), ci, ex);
    if (!content) {
        camel_object_unref (CAMEL_OBJECT (msg));
        return NULL;
    }

    camel_medium_set_content_object (CAMEL_MEDIUM (msg), content);
    camel_object_unref (CAMEL_OBJECT (content));

    return msg;
}

/* FIXME: I pulled this number out of my butt. */
#define IMAP_SMALL_BODY_SIZE 5120

static CamelMimeMessage *
imap_get_message (CamelFolder *folder, const char *uid, CamelException *ex)
{
    CamelMessageInfo *mi;
    CamelMimeMessage *msg;

    mi = camel_folder_summary_uid (folder->summary, uid);
    g_return_val_if_fail (mi != NULL, NULL);

    /* Fetch small messages directly. */
    if (mi->size < IMAP_SMALL_BODY_SIZE) {
        camel_folder_summary_info_free (folder->summary, mi);
        return (CamelMimeMessage *)fetch_medium (folder, uid, "", CAMEL_MIME_MESSAGE_TYPE, ex);
    }

    /* For larger messages, fetch the structure and build a message
     * with offline parts. (We check mi->content->type rather than
     * mi->content because camel_folder_summary_info_new always creates
     * an empty content struct.)
     */
    if (!mi->content->type) {
        CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
        CamelImapResponse *response;
        char *result, *p;

        CAMEL_IMAP_STORE_LOCK (store, command_lock);
        response = camel_imap_command (store, folder, ex,
                           "UID FETCH %s BODY", uid);
        CAMEL_IMAP_STORE_UNLOCK (store, command_lock);
        if (!response) {
            camel_folder_summary_info_free (folder->summary, mi);
            return NULL;
        }
        /* FIXME, wrong */
        result = camel_imap_response_extract (response, "FETCH", ex);
        if (!result) {
            camel_folder_summary_info_free (folder->summary, mi);
            return NULL;
        }

        p = e_strstrcase (result, "BODY ");
        if (p) {
            p += 5;
            imap_parse_body (&p, folder, mi->content);
        }
        g_free (result);
        if (!mi->content->type) {
            camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                          _("Could not find message body in FETCH response."));
            camel_folder_summary_info_free (folder->summary, mi);
            return NULL;
        }
    }

    msg = get_message (folder, uid, "", mi->content, ex);
    camel_folder_summary_info_free (folder->summary, mi);

    return msg;
}

static const char *
imap_protocol_get_summary_specifier (CamelImapStore *store)
{
    if (store->server_level >= IMAP_LEVEL_IMAP4REV1)
        return "UID FLAGS RFC822.SIZE BODY.PEEK[HEADER]";
    else
        return "UID FLAGS RFC822.SIZE RFC822.HEADER";
}

static void
imap_update_summary (CamelFolder *folder, int first, int last,
             CamelFolderChangeInfo *changes, CamelException *ex)
{
    CamelImapStore *store = CAMEL_IMAP_STORE (folder->parent_store);
    CamelImapResponse *response;
    GPtrArray *headers, *messages;
    const char *summary_specifier;
    char *p, *uid;
    int i, seq, count;
    CamelMimeMessage *msg;
    CamelMessageInfo *mi;
    guint32 flags, size;

    summary_specifier = imap_protocol_get_summary_specifier (store);
    /* We already have the command lock */
    if (first == last) {
        response = camel_imap_command (store, folder, ex,
                           "FETCH %d (%s)", first,
                           summary_specifier);
    } else {
        response = camel_imap_command (store, folder, ex,
                           "FETCH %d:%d (%s)", first,
                           last, summary_specifier);
    }

    if (!response)
        return;

    count = camel_folder_summary_count (folder->summary);
    messages = g_ptr_array_new ();
    g_ptr_array_set_size (messages, last - first + 1);
    headers = response->untagged;
    for (i = 0; i < headers->len; i++) {
        p = headers->pdata[i];
        if (*p++ != '*' || *p++ != ' ')
            continue;
        seq = strtoul (p, &p, 10);
        if (!seq || seq < count)
            continue;
        if (g_strncasecmp (p, " FETCH (", 8) != 0)
            continue;
        p += 8;

        mi = messages->pdata[seq - first];
        flags = size = 0;
        uid = NULL;
        while (p && *p != ')') {
            if (*p == ' ')
                p++;
            if (!g_strncasecmp (p, "FLAGS ", 6)) {
                p += 6;
                /* FIXME user flags */
                flags = imap_parse_flag_list (&p);
            } else if (!g_strncasecmp (p, "RFC822.SIZE ", 12)) {
                size = strtoul (p + 12, &p, 10);
            } else if (!g_strncasecmp (p, "UID ", 4)) {
                uid = p + 4;
                strtoul (uid, &p, 10);
                uid = g_strndup (uid, p - uid);
            } else if (!g_strncasecmp (p, "BODY[HEADER", 11) ||
                   !g_strncasecmp (p, "RFC822.HEADER", 13)) {
                msg = (CamelMimeMessage *) parse_headers (&p, CAMEL_MIME_MESSAGE_TYPE);
                mi = camel_folder_summary_info_new_from_message (folder->summary, msg);
                camel_object_unref (CAMEL_OBJECT (msg));
            } else {
                g_warning ("Waiter, I did not order this %.*s",
                       (int)strcspn (p, " \n"), p);
                p = NULL;
            }
        }

        /* Ideally we got everything on one line, but if we
         * we didn't, and we didn't get the body yet, then we
         * have to postpone this line for later.
         */
        if (mi == NULL) {
            p = headers->pdata[i];
            g_ptr_array_remove_index (headers, i);
            g_ptr_array_add (headers, p);
            continue;
        }

        messages->pdata[seq - first] = mi;
        if (uid)
            camel_message_info_set_uid (mi, uid);
        if (flags)
            mi->flags = flags;
        if (size)
            mi->size = size;
    }
    camel_imap_response_free (response);

    for (i = 0; i < messages->len; i++) {
        mi = messages->pdata[i];
        camel_folder_summary_add (folder->summary, mi);
        camel_folder_change_info_add_uid (changes, camel_message_info_uid (mi));
    }
    g_ptr_array_free (messages, TRUE);
}

/* Called with the store's command_lock locked */
void
camel_imap_folder_changed (CamelFolder *folder, int exists,
               GArray *expunged, CamelException *ex)
{
    CamelFolderChangeInfo *changes;
    CamelMessageInfo *info;
    int len;

    changes = camel_folder_change_info_new ();
    if (expunged) {
        int i, id;

        for (i = 0; i < expunged->len; i++) {
            id = g_array_index (expunged, int, i);
            info = camel_folder_summary_index (folder->summary, id - 1);
            camel_folder_change_info_remove_uid (changes, camel_message_info_uid (info));
            camel_folder_summary_remove (folder->summary, info);
            camel_folder_summary_info_free(folder->summary, info);
        }
    }

    len = camel_folder_summary_count (folder->summary);
    if (exists > len)
        imap_update_summary (folder, len + 1, exists, changes, ex);

    if (camel_folder_change_info_changed (changes)) {
        camel_object_trigger_event (CAMEL_OBJECT (folder),
                        "folder_changed", changes);
    }
    camel_folder_change_info_free (changes);
}