path: root/libemail-engine/mail-folder-cache.c

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Authors:
 *   Peter Williams <peterw@ximian.com>
 *   Michael Zucchi <notzed@ximian.com>
 *   Jonathon Jongsma <jonathon.jongsma@collabora.co.uk>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 * Copyright (C) 2009 Intel Corporation
 *
 */

/**
 * SECTION: mail-folder-cache
 * @short_description: Stores information about open folders
 **/

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

#include <string.h>
#include <time.h>

#include <glib/gi18n.h>
#include <glib/gstdio.h>

#include <libedataserver/libedataserver.h>

#include <libemail-engine/mail-mt.h>

#include "mail-folder-cache.h"
#include "e-mail-utils.h"
#include "e-mail-folder-utils.h"
#include "e-mail-session.h"
#include "e-mail-store-utils.h"

#define w(x)
#define d(x)

#define MAIL_FOLDER_CACHE_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), MAIL_TYPE_FOLDER_CACHE, MailFolderCachePrivate))

/* This code is a mess, there is no reason it should be so complicated. */

typedef struct _StoreInfo StoreInfo;

struct _MailFolderCachePrivate {
    gpointer session;  /* weak pointer */

    /* source id for the ping timeout callback */
    guint ping_id;
    /* Store to storeinfo table, active stores */
    GHashTable *stores;
    /* mutex to protect access to the stores hash */
    GRecMutex stores_mutex;
    /* List of folder changes to be executed in gui thread */
    GQueue updates;
    /* idle source id for flushing all pending updates */
    guint update_id;
    /* hack for people who LIKE to have unsent count */
    gint count_sent;
    gint count_trash;

    GQueue local_folder_uris;
    GQueue remote_folder_uris;
};

enum {
    PROP_0,
    PROP_SESSION
};

enum {
    FOLDER_AVAILABLE,
    FOLDER_UNAVAILABLE,
    FOLDER_DELETED,
    FOLDER_RENAMED,
    FOLDER_UNREAD_UPDATED,
    FOLDER_CHANGED,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL];

struct _folder_info {
    StoreInfo *store_info;  /* 'parent' link */

    gchar *full_name;   /* full name of folder/folderinfo */

    guint32 flags;
    gboolean has_children;

    gpointer folder;    /* if known (weak pointer) */
};

/* pending list of updates */
struct _folder_update {
    guint remove:1; /* removing from vfolders */
    guint delete:1; /* deleting as well? */
    guint add:1;    /* add to vfolder */
    guint unsub:1;   /* unsubcribing? */
    guint new;     /* new mail arrived? */

    gchar *full_name;
    gchar *oldfull;

    gint unread;
    CamelStore *store;

    /* for only one new message... */
    gchar *msg_uid;     /* ... its uid ... */
    gchar *msg_sender;  /* ... its sender ... */
    gchar *msg_subject; /* ... and its subject. */
};

struct _StoreInfo {
    GHashTable *folders;    /* by full_name */
    CamelStore *store;  /* the store for these folders */
    gboolean first_update;  /* TRUE initially, then FALSE forever */

    /* Hold a reference to keep them alive. */
    CamelFolder *vjunk;
    CamelFolder *vtrash;

    /* Outstanding folderinfo requests */
    GQueue folderinfo_updates;
};

struct _update_data {
    NoteDoneFunc done;
    gpointer data;
    MailFolderCache *cache;
    GCancellable *cancellable;
};

G_DEFINE_TYPE (MailFolderCache, mail_folder_cache, G_TYPE_OBJECT)

static void
free_update (struct _folder_update *up)
{
    g_free (up->full_name);
    if (up->store)
        g_object_unref (up->store);
    g_free (up->oldfull);
    g_free (up->msg_uid);
    g_free (up->msg_sender);
    g_free (up->msg_subject);
    g_free (up);
}

static void
free_folder_info (struct _folder_info *mfi)
{
    g_free (mfi->full_name);
    g_free (mfi);
}

static StoreInfo *
store_info_new (CamelStore *store)
{
    StoreInfo *info;
    GHashTable *folders;

    folders = g_hash_table_new_full (
        (GHashFunc) g_str_hash,
        (GEqualFunc) g_str_equal,
        (GDestroyNotify) NULL,
        (GDestroyNotify) free_folder_info);

    info = g_slice_new0 (StoreInfo);
    info->folders = folders;
    info->store = g_object_ref (store);
    info->first_update = TRUE;

    /* If these are vfolders then they need to be opened
     * now, otherwise they won't keep track of all folders. */
    if (store->flags & CAMEL_STORE_VJUNK)
        info->vjunk = camel_store_get_junk_folder_sync (
            store, NULL, NULL);
    if (store->flags & CAMEL_STORE_VTRASH)
        info->vtrash = camel_store_get_trash_folder_sync (
            store, NULL, NULL);

    g_queue_init (&info->folderinfo_updates);

    return info;
}

static void
store_info_free (StoreInfo *info)
{
    struct _update_data *ud;

    while (!g_queue_is_empty (&info->folderinfo_updates)) {
        ud = g_queue_pop_head (&info->folderinfo_updates);
        g_cancellable_cancel (ud->cancellable);
    }

    g_hash_table_destroy (info->folders);
    g_object_unref (info->store);

    if (info->vjunk != NULL)
        g_object_unref (info->vjunk);

    if (info->vtrash != NULL)
        g_object_unref (info->vtrash);

    g_slice_free (StoreInfo, info);
}

static gboolean
flush_updates_idle_cb (MailFolderCache *cache)
{
    struct _folder_update *up;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    while ((up = g_queue_pop_head (&cache->priv->updates)) != NULL) {
        g_rec_mutex_unlock (&cache->priv->stores_mutex);

        if (up->remove) {
            if (up->delete) {
                g_signal_emit (
                    cache, signals[FOLDER_DELETED], 0,
                    up->store, up->full_name);
            } else
                g_signal_emit (
                    cache, signals[FOLDER_UNAVAILABLE], 0,
                    up->store, up->full_name);
        } else {
            if (up->oldfull && up->add) {
                g_signal_emit (
                    cache, signals[FOLDER_RENAMED], 0,
                    up->store, up->oldfull, up->full_name);
            }

            if (!up->oldfull && up->add)
                g_signal_emit (
                    cache, signals[FOLDER_AVAILABLE], 0,
                    up->store, up->full_name);
        }

        /* update unread counts */
        g_signal_emit (
            cache, signals[FOLDER_UNREAD_UPDATED], 0,
            up->store, up->full_name, up->unread);

        /* indicate that the folder has changed (new mail received, etc) */
        if (up->store != NULL && up->full_name != NULL) {
            g_signal_emit (
                cache, signals[FOLDER_CHANGED], 0, up->store,
                up->full_name, up->new, up->msg_uid,
                up->msg_sender, up->msg_subject);
        }

        if (CAMEL_IS_VEE_STORE (up->store) && !up->remove) {
            /* Normally the vfolder store takes care of the
             * folder_opened event itself, but we add folder to
             * the noting system later, thus we do not know about
             * search folders to update them in a tree, thus
             * ensure their changes will be tracked correctly. */
            CamelFolder *folder;

            /* FIXME camel_store_get_folder_sync() may block. */
            folder = camel_store_get_folder_sync (
                up->store, up->full_name, 0, NULL, NULL);

            if (folder) {
                mail_folder_cache_note_folder (cache, folder);
                g_object_unref (folder);
            }
        }

        free_update (up);

        g_rec_mutex_lock (&cache->priv->stores_mutex);
    }
    cache->priv->update_id = 0;
    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    return FALSE;
}

static void
flush_updates (MailFolderCache *cache)
{
    if (cache->priv->update_id > 0)
        return;

    if (g_queue_is_empty (&cache->priv->updates))
        return;

    cache->priv->update_id = g_idle_add (
        (GSourceFunc) flush_updates_idle_cb, cache);
}

/* This is how unread counts work (and don't work):
 *
 * camel_folder_unread_message_count() only gives a correct answer if
 * the store is paying attention to the folder. (Some stores always
 * pay attention to all folders, but IMAP can only pay attention to
 * one folder at a time.) But it doesn't have any way to know when
 * it's lying, so it's only safe to call it when you know for sure
 * that the store is paying attention to the folder, such as when it's
 * just been created, or you get a folder_changed signal on it.
 *
 * camel_store_get_folder_info() always gives correct answers for the
 * folders it checks, but it can also return -1 for a folder, meaning
 * it didn't check, and so you should stick with your previous answer.
 *
 * update_1folder is called from three places: with info != NULL when
 * the folder is created (or get_folder_info), with info == NULL when
 * a folder changed event is emitted.
 *
 * So if info is NULL, camel_folder_unread_message_count is correct,
 * and if it's not NULL and its unread_message_count isn't -1, then
 * it's correct.  */

static void
update_1folder (MailFolderCache *cache,
                struct _folder_info *mfi,
                gint new,
                const gchar *msg_uid,
                const gchar *msg_sender,
                const gchar *msg_subject,
                CamelFolderInfo *info)
{
    EMailSession *session;
    ESourceRegistry *registry;
    struct _folder_update *up;
    CamelFolder *folder;
    gint unread = -1;
    gint deleted;

    session = mail_folder_cache_get_session (cache);
    registry = e_mail_session_get_registry (session);

    folder = mfi->folder;
    if (folder) {
        gboolean folder_is_sent;
        gboolean folder_is_drafts;
        gboolean folder_is_outbox;
        gboolean folder_is_vtrash;
        gboolean special_case;

        folder_is_sent = em_utils_folder_is_sent (registry, folder);
        folder_is_drafts = em_utils_folder_is_drafts (registry, folder);
        folder_is_outbox = em_utils_folder_is_outbox (registry, folder);
        folder_is_vtrash = CAMEL_IS_VTRASH_FOLDER (folder);

        special_case =
            (cache->priv->count_trash && folder_is_vtrash) ||
            (cache->priv->count_sent && folder_is_sent) ||
            folder_is_drafts || folder_is_outbox;

        if (special_case) {
            d (printf (" total count\n"));
            unread = camel_folder_get_message_count (folder);
            if (folder_is_drafts || folder_is_outbox) {
                guint32 junked = 0;

                deleted = camel_folder_get_deleted_message_count (folder);
                if (deleted > 0)
                    unread -= deleted;

                junked = camel_folder_summary_get_junk_count (folder->summary);
                if (junked > 0)
                    unread -= junked;
            }
        } else {
            d (printf (" unread count\n"));
            if (info)
                unread = info->unread;
            else
                unread = camel_folder_get_unread_message_count (folder);
        }
    }

    d (printf ("folder updated: unread %d: '%s'\n", unread, mfi->full_name));

    if (unread == -1)
        return;

    up = g_malloc0 (sizeof (*up));
    up->full_name = g_strdup (mfi->full_name);
    up->unread = unread;
    up->new = new;
    up->store = g_object_ref (mfi->store_info->store);
    up->msg_uid = g_strdup (msg_uid);
    up->msg_sender = g_strdup (msg_sender);
    up->msg_subject = g_strdup (msg_subject);
    g_queue_push_tail (&cache->priv->updates, up);
    flush_updates (cache);
}

static void
folder_changed_cb (CamelFolder *folder,
                   CamelFolderChangeInfo *changes,
                   MailFolderCache *cache)
{
    static GHashTable *last_newmail_per_folder = NULL;
    time_t latest_received, new_latest_received;
    CamelFolder *local_drafts;
    CamelFolder *local_outbox;
    CamelFolder *local_sent;
    CamelSession *session;
    CamelStore *parent_store;
    CamelMessageInfo *info;
    StoreInfo *si;
    struct _folder_info *mfi;
    const gchar *full_name;
    gint new = 0;
    gint i;
    guint32 flags;
    gchar *uid = NULL, *sender = NULL, *subject = NULL;

    full_name = camel_folder_get_full_name (folder);
    parent_store = camel_folder_get_parent_store (folder);
    session = camel_service_get_session (CAMEL_SERVICE (parent_store));

    if (!last_newmail_per_folder)
        last_newmail_per_folder = g_hash_table_new (g_direct_hash, g_direct_equal);

    /* it's fine to hash them by folder pointer here */
    latest_received = GPOINTER_TO_INT (
        g_hash_table_lookup (last_newmail_per_folder, folder));
    new_latest_received = latest_received;

    local_drafts = e_mail_session_get_local_folder (
        E_MAIL_SESSION (session), E_MAIL_LOCAL_FOLDER_DRAFTS);
    local_outbox = e_mail_session_get_local_folder (
        E_MAIL_SESSION (session), E_MAIL_LOCAL_FOLDER_OUTBOX);
    local_sent = e_mail_session_get_local_folder (
        E_MAIL_SESSION (session), E_MAIL_LOCAL_FOLDER_SENT);

    if (!CAMEL_IS_VEE_FOLDER (folder)
        && folder != local_drafts
        && folder != local_outbox
        && folder != local_sent
        && changes && (changes->uid_added->len > 0)) {
        /* for each added message, check to see that it is
         * brand new, not junk and not already deleted */
        for (i = 0; i < changes->uid_added->len; i++) {
            info = camel_folder_get_message_info (
                folder, changes->uid_added->pdata[i]);
            if (info) {
                flags = camel_message_info_flags (info);
                if (((flags & CAMEL_MESSAGE_SEEN) == 0) &&
                    ((flags & CAMEL_MESSAGE_JUNK) == 0) &&
                    ((flags & CAMEL_MESSAGE_DELETED) == 0) &&
                    (camel_message_info_date_received (info) > latest_received)) {
                    if (camel_message_info_date_received (info) > new_latest_received)
                        new_latest_received = camel_message_info_date_received (info);
                    new++;
                    if (new == 1) {
                        uid = g_strdup (camel_message_info_uid (info));
                        sender = g_strdup (camel_message_info_from (info));
                        subject = g_strdup (camel_message_info_subject (info));
                    } else {
                        g_free (uid);
                        g_free (sender);
                        g_free (subject);

                        uid = NULL;
                        sender = NULL;
                        subject = NULL;
                    }
                }
                camel_folder_free_message_info (folder, info);
            }
        }
    }

    if (new > 0)
        g_hash_table_insert (
            last_newmail_per_folder, folder,
            GINT_TO_POINTER (new_latest_received));

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    if (cache->priv->stores != NULL
        && (si = g_hash_table_lookup (cache->priv->stores, parent_store)) != NULL
        && (mfi = g_hash_table_lookup (si->folders, full_name)) != NULL
        && mfi->folder == folder) {
        update_1folder (cache, mfi, new, uid, sender, subject, NULL);
    }
    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    g_free (uid);
    g_free (sender);
    g_free (subject);
}

static void
unset_folder_info (MailFolderCache *cache,
                   struct _folder_info *mfi,
                   gint delete,
                   gint unsub)
{
    struct _folder_update *up;

    d (printf ("unset folderinfo '%s'\n", mfi->uri));

    if (mfi->folder) {
        CamelFolder *folder = mfi->folder;

        g_signal_handlers_disconnect_by_func (
            folder, folder_changed_cb, cache);

        g_object_remove_weak_pointer (
            G_OBJECT (mfi->folder), &mfi->folder);
    }

    if ((mfi->flags & CAMEL_FOLDER_NOSELECT) == 0) {
        up = g_malloc0 (sizeof (*up));

        up->remove = TRUE;
        up->delete = delete;
        up->unsub = unsub;
        up->store = g_object_ref (mfi->store_info->store);
        up->full_name = g_strdup (mfi->full_name);

        g_queue_push_tail (&cache->priv->updates, up);
        flush_updates (cache);
    }
}

static void
setup_folder (MailFolderCache *cache,
              CamelFolderInfo *fi,
              StoreInfo *si)
{
    struct _folder_info *mfi;
    struct _folder_update *up;

    mfi = g_hash_table_lookup (si->folders, fi->full_name);
    if (mfi) {
        update_1folder (cache, mfi, 0, NULL, NULL, NULL, fi);
    } else {
        mfi = g_malloc0 (sizeof (*mfi));
        mfi->full_name = g_strdup (fi->full_name);
        mfi->store_info = si;
        mfi->flags = fi->flags;
        mfi->has_children = fi->child != NULL;

        g_hash_table_insert (si->folders, mfi->full_name, mfi);

        up = g_malloc0 (sizeof (*up));
        up->full_name = g_strdup (mfi->full_name);
        up->unread = fi->unread;
        up->store = g_object_ref (si->store);

        if ((fi->flags & CAMEL_FOLDER_NOSELECT) == 0)
            up->add = TRUE;

        g_queue_push_tail (&cache->priv->updates, up);
        flush_updates (cache);
    }
}

static void
create_folders (MailFolderCache *cache,
                CamelFolderInfo *fi,
                StoreInfo *si)
{
    while (fi) {
        setup_folder (cache, fi, si);

        if (fi->child)
            create_folders (cache, fi->child, si);

        fi = fi->next;
    }
}

static void
store_folder_subscribed_cb (CamelStore *store,
                            CamelFolderInfo *info,
                            MailFolderCache *cache)
{
    StoreInfo *si;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    si = g_hash_table_lookup (cache->priv->stores, store);
    if (si)
        setup_folder (cache, info, si);
    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
store_folder_created_cb (CamelStore *store,
                         CamelFolderInfo *info,
                         MailFolderCache *cache)
{
    /* We only want created events to do more work
     * if we dont support subscriptions. */
    if (!CAMEL_IS_SUBSCRIBABLE (store))
        store_folder_subscribed_cb (store, info, cache);
}

static void
store_folder_opened_cb (CamelStore *store,
                        CamelFolder *folder,
                        MailFolderCache *cache)
{
    mail_folder_cache_note_folder (cache, folder);
}

static void
store_folder_unsubscribed_cb (CamelStore *store,
                              CamelFolderInfo *info,
                              MailFolderCache *cache)
{
    StoreInfo *si;
    struct _folder_info *mfi;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    si = g_hash_table_lookup (cache->priv->stores, store);
    if (si) {
        mfi = g_hash_table_lookup (si->folders, info->full_name);
        if (mfi) {
            unset_folder_info (cache, mfi, TRUE, TRUE);
            g_hash_table_remove (si->folders, mfi->full_name);
        }
    }
    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
store_folder_deleted_cb (CamelStore *store,
                         CamelFolderInfo *info,
                         MailFolderCache *cache)
{
    /* We only want deleted events to do more work
     * if we dont support subscriptions. */
    if (!CAMEL_IS_SUBSCRIBABLE (store))
        store_folder_unsubscribed_cb (store, info, cache);
}

static void
rename_folders (MailFolderCache *cache,
                StoreInfo *si,
                const gchar *oldbase,
                const gchar *newbase,
                CamelFolderInfo *fi)
{
    gchar *old, *olduri, *oldfile, *newuri, *newfile;
    struct _folder_info *mfi;
    struct _folder_update *up;
    const gchar *config_dir;

    up = g_malloc0 (sizeof (*up));

    /* Form what was the old name, and try and look it up */
    old = g_strdup_printf ("%s%s", oldbase, fi->full_name + strlen (newbase));
    mfi = g_hash_table_lookup (si->folders, old);
    if (mfi) {
        up->oldfull = mfi->full_name;

        /* Be careful not to invoke the destroy function. */
        g_hash_table_steal (si->folders, mfi->full_name);

        /* Its a rename op */
        mfi->full_name = g_strdup (fi->full_name);
        mfi->flags = fi->flags;
        mfi->has_children = fi->child != NULL;

        g_hash_table_insert (si->folders, mfi->full_name, mfi);
    } else {
        /* Its a new op */
        mfi = g_malloc0 (sizeof (*mfi));
        mfi->full_name = g_strdup (fi->full_name);
        mfi->store_info = si;
        mfi->flags = fi->flags;
        mfi->has_children = fi->child != NULL;

        g_hash_table_insert (si->folders, mfi->full_name, mfi);
    }

    up->full_name = g_strdup (mfi->full_name);
    up->unread = fi->unread==-1 ? 0 : fi->unread;
    up->store = g_object_ref (si->store);

    if ((fi->flags & CAMEL_FOLDER_NOSELECT) == 0)
        up->add = TRUE;

    g_queue_push_tail (&cache->priv->updates, up);
    flush_updates (cache);

    /* rename the meta-data we maintain ourselves */
    config_dir = mail_session_get_config_dir ();
    olduri = e_mail_folder_uri_build (si->store, old);
    e_filename_make_safe (olduri);
    newuri = e_mail_folder_uri_build (si->store, fi->full_name);
    e_filename_make_safe (newuri);
    oldfile = g_strdup_printf ("%s/custom_view-%s.xml", config_dir, olduri);
    newfile = g_strdup_printf ("%s/custom_view-%s.xml", config_dir, newuri);
    g_rename (oldfile, newfile);
    g_free (oldfile);
    g_free (newfile);
    oldfile = g_strdup_printf ("%s/current_view-%s.xml", config_dir, olduri);
    newfile = g_strdup_printf ("%s/current_view-%s.xml", config_dir, newuri);
    g_rename (oldfile, newfile);
    g_free (oldfile);
    g_free (newfile);
    g_free (olduri);
    g_free (newuri);

    g_free (old);
}

static void
get_folders (CamelFolderInfo *fi,
             GPtrArray *folders)
{
    while (fi) {
        g_ptr_array_add (folders, fi);

        if (fi->child)
            get_folders (fi->child, folders);

        fi = fi->next;
    }
}

static gint
folder_cmp (gconstpointer ap,
            gconstpointer bp)
{
    const CamelFolderInfo *a = ((CamelFolderInfo **) ap)[0];
    const CamelFolderInfo *b = ((CamelFolderInfo **) bp)[0];

    return strcmp (a->full_name, b->full_name);
}

static void
store_folder_renamed_cb (CamelStore *store,
                         const gchar *old_name,
                         CamelFolderInfo *info,
                         MailFolderCache *cache)
{
    StoreInfo *si;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    si = g_hash_table_lookup (cache->priv->stores, store);
    if (si) {
        GPtrArray *folders = g_ptr_array_new ();
        CamelFolderInfo *top;
        gint i;

        /* Ok, so for some reason the folderinfo we have comes in all messed up from
         * imap, should find out why ... this makes it workable */
        get_folders (info, folders);
        qsort (folders->pdata, folders->len, sizeof (folders->pdata[0]), folder_cmp);

        top = folders->pdata[0];
        for (i = 0; i < folders->len; i++) {
            rename_folders (cache, si, old_name, top->full_name, folders->pdata[i]);
        }

        g_ptr_array_free (folders, TRUE);

    }
    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
unset_folder_info_hash (gchar *path,
                        struct _folder_info *mfi,
                        gpointer data)
{
    MailFolderCache *cache = (MailFolderCache *) data;
    unset_folder_info (cache, mfi, FALSE, FALSE);
}

static void
mail_folder_cache_first_update (MailFolderCache *cache,
                                StoreInfo *info)
{
    EMailSession *session;
    const gchar *uid;

    session = mail_folder_cache_get_session (cache);
    uid = camel_service_get_uid (CAMEL_SERVICE (info->store));

    if (info->vjunk != NULL)
        mail_folder_cache_note_folder (cache, info->vjunk);

    if (info->vtrash != NULL)
        mail_folder_cache_note_folder (cache, info->vtrash);

    /* Some extra work for the "On This Computer" store. */
    if (g_strcmp0 (uid, E_MAIL_SESSION_LOCAL_UID) == 0) {
        CamelFolder *folder;
        gint ii;

        for (ii = 0; ii < E_MAIL_NUM_LOCAL_FOLDERS; ii++) {
            folder = e_mail_session_get_local_folder (session, ii);
            mail_folder_cache_note_folder (cache, folder);
        }
    }
}

static void
update_folders (CamelStore *store,
                GAsyncResult *result,
                struct _update_data *ud)
{
    CamelFolderInfo *fi;
    StoreInfo *si;
    GError *error = NULL;
    gboolean free_fi = TRUE;

    fi = camel_store_get_folder_info_finish (store, result, &error);

    /* Silently ignore cancellation errors. */
    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
        g_error_free (error);

    } else if (error != NULL) {
        g_warning ("%s", error->message);
        g_error_free (error);
    }

    g_rec_mutex_lock (&ud->cache->priv->stores_mutex);
    si = g_hash_table_lookup (ud->cache->priv->stores, store);
    if (si && !g_cancellable_is_cancelled (ud->cancellable)) {
        /* The 'si' is still there, so we can remove ourselves from
         * its list.  Or else its not, and we're on our own and free
         * anyway. */
        g_queue_remove (&si->folderinfo_updates, ud);

        if (fi != NULL)
            create_folders (ud->cache, fi, si);
    }
    g_rec_mutex_unlock (&ud->cache->priv->stores_mutex);

    /* Do some extra work for the first update. */
    if (si != NULL && si->first_update) {
        mail_folder_cache_first_update (ud->cache, si);
        si->first_update = FALSE;
    }

    if (ud->done != NULL)
        free_fi = ud->done (ud->cache, store, fi, ud->data);
    if (fi && free_fi)
        camel_store_free_folder_info (store, fi);

    if (ud->cancellable != NULL)
        g_object_unref (ud->cancellable);

    g_free (ud);
}

struct _ping_store_msg {
    MailMsg base;
    CamelStore *store;
};

static gchar *
ping_store_desc (struct _ping_store_msg *m)
{
    gchar *service_name;
    gchar *msg;

    service_name = camel_service_get_name (CAMEL_SERVICE (m->store), TRUE);
    msg = g_strdup_printf (_("Pinging %s"), service_name);
    g_free (service_name);

    return msg;
}

static void
ping_store_exec (struct _ping_store_msg *m,
                 GCancellable *cancellable,
                 GError **error)
{
    CamelServiceConnectionStatus status;
    CamelService *service;
    gboolean online = FALSE;

    service = CAMEL_SERVICE (m->store);
    status = camel_service_get_connection_status (service);

    if (status == CAMEL_SERVICE_CONNECTED) {
        if (CAMEL_IS_DISCO_STORE (m->store) &&
            camel_disco_store_status (
            CAMEL_DISCO_STORE (m->store)) !=CAMEL_DISCO_STORE_OFFLINE)
            online = TRUE;
        else if (CAMEL_IS_OFFLINE_STORE (m->store) &&
            camel_offline_store_get_online (
            CAMEL_OFFLINE_STORE (m->store)))
            online = TRUE;
    }
    if (online)
        camel_store_noop_sync (m->store, cancellable, error);
}

static void
ping_store_free (struct _ping_store_msg *m)
{
    g_object_unref (m->store);
}

static MailMsgInfo ping_store_info = {
    sizeof (struct _ping_store_msg),
    (MailMsgDescFunc) ping_store_desc,
    (MailMsgExecFunc) ping_store_exec,
    (MailMsgDoneFunc) NULL,
    (MailMsgFreeFunc) ping_store_free
};

static void
ping_store (CamelStore *store)
{
    CamelServiceConnectionStatus status;
    CamelService *service;
    struct _ping_store_msg *m;

    service = CAMEL_SERVICE (store);
    status = camel_service_get_connection_status (service);

    if (status != CAMEL_SERVICE_CONNECTED)
        return;

    m = mail_msg_new (&ping_store_info);
    m->store = g_object_ref (store);

    mail_msg_slow_ordered_push (m);
}

static gboolean
ping_cb (MailFolderCache *cache)
{
    g_rec_mutex_lock (&cache->priv->stores_mutex);

    g_hash_table_foreach (cache->priv->stores, (GHFunc) ping_store, NULL);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    return TRUE;
}

static gboolean
store_has_folder_hierarchy (CamelStore *store)
{
    CamelProvider *provider;

    g_return_val_if_fail (store != NULL, FALSE);

    provider = camel_service_get_provider (CAMEL_SERVICE (store));
    g_return_val_if_fail (provider != NULL, FALSE);

    if (provider->flags & CAMEL_PROVIDER_IS_STORAGE)
        return TRUE;

    if (provider->flags & CAMEL_PROVIDER_IS_EXTERNAL)
        return TRUE;

    return FALSE;
}

static void
store_go_online_cb (CamelStore *store,
                    GAsyncResult *result,
                    struct _update_data *ud)
{
    /* FIXME Not checking result for error. */

    g_rec_mutex_lock (&ud->cache->priv->stores_mutex);

    if (g_hash_table_lookup (ud->cache->priv->stores, store) != NULL &&
        !g_cancellable_is_cancelled (ud->cancellable)) {
        /* We're already in the store update list. */
        if (store_has_folder_hierarchy (store))
            camel_store_get_folder_info (
                store, NULL,
                CAMEL_STORE_FOLDER_INFO_FAST |
                CAMEL_STORE_FOLDER_INFO_RECURSIVE |
                CAMEL_STORE_FOLDER_INFO_SUBSCRIBED,
                G_PRIORITY_DEFAULT, ud->cancellable,
                (GAsyncReadyCallback) update_folders, ud);
    } else {
        /* The store vanished, that means we were probably cancelled,
         * or at any rate, need to clean ourselves up. */
        if (ud->cancellable != NULL)
            g_object_unref (ud->cancellable);
        g_free (ud);
    }

    g_rec_mutex_unlock (&ud->cache->priv->stores_mutex);
}

static GList *
find_folder_uri (GQueue *queue,
                 CamelSession *session,
                 const gchar *folder_uri)
{
    GList *head, *link;

    head = g_queue_peek_head_link (queue);

    for (link = head; link != NULL; link = g_list_next (link))
        if (e_mail_folder_uri_equal (session, link->data, folder_uri))
            break;

    return link;
}

struct _find_info {
    const gchar *folder_uri;
    struct _folder_info *fi;
};

static void
storeinfo_find_folder_info (CamelStore *store,
                            StoreInfo *si,
                            struct _find_info *fi)
{
    gchar *folder_name;
    gboolean success;

    if (fi->fi != NULL)
        return;

    success = e_mail_folder_uri_parse (
        camel_service_get_session (CAMEL_SERVICE (store)),
        fi->folder_uri, NULL, &folder_name, NULL);

    if (success) {
        fi->fi = g_hash_table_lookup (si->folders, folder_name);
        g_free (folder_name);
    }
}

static void
mail_folder_cache_set_session (MailFolderCache *cache,
                               EMailSession *session)
{
    g_return_if_fail (E_IS_MAIL_SESSION (session));
    g_return_if_fail (cache->priv->session == NULL);

    cache->priv->session = session;

    g_object_add_weak_pointer (
        G_OBJECT (cache->priv->session),
        &cache->priv->session);
}

static void
mail_folder_cache_set_property (GObject *object,
                                guint property_id,
                                const GValue *value,
                                GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_SESSION:
            mail_folder_cache_set_session (
                MAIL_FOLDER_CACHE (object),
                g_value_get_object (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
mail_folder_cache_get_property (GObject *object,
                                guint property_id,
                                GValue *value,
                                GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_SESSION:
            g_value_set_object (
                value,
                mail_folder_cache_get_session (
                MAIL_FOLDER_CACHE (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
mail_folder_cache_dispose (GObject *object)
{
    MailFolderCachePrivate *priv;

    priv = MAIL_FOLDER_CACHE_GET_PRIVATE (object);

    if (priv->session != NULL) {
        g_object_remove_weak_pointer (
            G_OBJECT (priv->session), &priv->session);
        priv->session = NULL;
    }

    /* Chain up to parent's dispose() method. */
    G_OBJECT_CLASS (mail_folder_cache_parent_class)->dispose (object);
}

static void
mail_folder_cache_finalize (GObject *object)
{
    MailFolderCachePrivate *priv;

    priv = MAIL_FOLDER_CACHE_GET_PRIVATE (object);

    g_hash_table_destroy (priv->stores);
    g_rec_mutex_clear (&priv->stores_mutex);

    if (priv->ping_id > 0) {
        g_source_remove (priv->ping_id);
        priv->ping_id = 0;
    }

    if (priv->update_id > 0) {
        g_source_remove (priv->update_id);
        priv->update_id = 0;
    }

    while (!g_queue_is_empty (&priv->local_folder_uris))
        g_free (g_queue_pop_head (&priv->local_folder_uris));

    while (!g_queue_is_empty (&priv->remote_folder_uris))
        g_free (g_queue_pop_head (&priv->remote_folder_uris));

    /* Chain up to parent's finalize() method. */
    G_OBJECT_CLASS (mail_folder_cache_parent_class)->finalize (object);
}

static void
mail_folder_cache_folder_available (MailFolderCache *cache,
                                    CamelStore *store,
                                    const gchar *folder_name)
{
    CamelService *service;
    CamelSession *session;
    CamelProvider *provider;
    GQueue *queue;
    gchar *folder_uri;

    /* Disregard virtual stores. */
    if (CAMEL_IS_VEE_STORE (store))
        return;

    /* Disregard virtual Junk folders. */
    if (store->flags & CAMEL_STORE_VJUNK)
        if (g_strcmp0 (folder_name, CAMEL_VJUNK_NAME) == 0)
            return;

    /* Disregard virtual Trash folders. */
    if (store->flags & CAMEL_STORE_VTRASH)
        if (g_strcmp0 (folder_name, CAMEL_VTRASH_NAME) == 0)
            return;

    service = CAMEL_SERVICE (store);
    session = camel_service_get_session (service);
    provider = camel_service_get_provider (service);

    /* Reuse the stores mutex just because it's handy. */
    g_rec_mutex_lock (&cache->priv->stores_mutex);

    folder_uri = e_mail_folder_uri_build (store, folder_name);

    if (provider->flags & CAMEL_PROVIDER_IS_REMOTE)
        queue = &cache->priv->remote_folder_uris;
    else
        queue = &cache->priv->local_folder_uris;

    if (find_folder_uri (queue, session, folder_uri) == NULL)
        g_queue_push_tail (queue, folder_uri);
    else
        g_free (folder_uri);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
mail_folder_cache_folder_unavailable (MailFolderCache *cache,
                                      CamelStore *store,
                                      const gchar *folder_name)
{
    CamelService *service;
    CamelSession *session;
    CamelProvider *provider;
    GQueue *queue;
    GList *link;
    gchar *folder_uri;

    /* Disregard virtual stores. */
    if (CAMEL_IS_VEE_STORE (store))
        return;

    /* Disregard virtual Junk folders. */
    if (store->flags & CAMEL_STORE_VJUNK)
        if (g_strcmp0 (folder_name, CAMEL_VJUNK_NAME) == 0)
            return;

    /* Disregard virtual Trash folders. */
    if (store->flags & CAMEL_STORE_VTRASH)
        if (g_strcmp0 (folder_name, CAMEL_VTRASH_NAME) == 0)
            return;

    service = CAMEL_SERVICE (store);
    session = camel_service_get_session (service);
    provider = camel_service_get_provider (service);

    /* Reuse the stores mutex just because it's handy. */
    g_rec_mutex_lock (&cache->priv->stores_mutex);

    folder_uri = e_mail_folder_uri_build (store, folder_name);

    if (provider->flags & CAMEL_PROVIDER_IS_REMOTE)
        queue = &cache->priv->remote_folder_uris;
    else
        queue = &cache->priv->local_folder_uris;

    link = find_folder_uri (queue, session, folder_uri);
    if (link != NULL) {
        g_free (link->data);
        g_queue_delete_link (queue, link);
    }

    g_free (folder_uri);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
mail_folder_cache_folder_deleted (MailFolderCache *cache,
                                  CamelStore *store,
                                  const gchar *folder_name)
{
    CamelService *service;
    CamelSession *session;
    GQueue *queue;
    GList *link;
    gchar *folder_uri;

    /* Disregard virtual stores. */
    if (CAMEL_IS_VEE_STORE (store))
        return;

    /* Disregard virtual Junk folders. */
    if (store->flags & CAMEL_STORE_VJUNK)
        if (g_strcmp0 (folder_name, CAMEL_VJUNK_NAME) == 0)
            return;

    /* Disregard virtual Trash folders. */
    if (store->flags & CAMEL_STORE_VTRASH)
        if (g_strcmp0 (folder_name, CAMEL_VTRASH_NAME) == 0)
            return;

    service = CAMEL_SERVICE (store);
    session = camel_service_get_session (service);

    /* Reuse the stores mutex just because it's handy. */
    g_rec_mutex_lock (&cache->priv->stores_mutex);

    folder_uri = e_mail_folder_uri_build (store, folder_name);

    queue = &cache->priv->local_folder_uris;
    link = find_folder_uri (queue, session, folder_uri);
    if (link != NULL) {
        g_free (link->data);
        g_queue_delete_link (queue, link);
    }

    queue = &cache->priv->remote_folder_uris;
    link = find_folder_uri (queue, session, folder_uri);
    if (link != NULL) {
        g_free (link->data);
        g_queue_delete_link (queue, link);
    }

    g_free (folder_uri);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

static void
mail_folder_cache_class_init (MailFolderCacheClass *class)
{
    GObjectClass *object_class;

    g_type_class_add_private (class, sizeof (MailFolderCachePrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = mail_folder_cache_set_property;
    object_class->get_property = mail_folder_cache_get_property;
    object_class->dispose = mail_folder_cache_dispose;
    object_class->finalize = mail_folder_cache_finalize;

    class->folder_available = mail_folder_cache_folder_available;
    class->folder_unavailable = mail_folder_cache_folder_unavailable;
    class->folder_deleted = mail_folder_cache_folder_deleted;

    g_object_class_install_property (
        object_class,
        PROP_SESSION,
        g_param_spec_object (
            "session",
            "Session",
            "Mail session",
            E_TYPE_MAIL_SESSION,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT_ONLY |
            G_PARAM_STATIC_STRINGS));

    /**
     * MailFolderCache::folder-available
     * @store: the #CamelStore containing the folder
     * @folder_name: the name of the folder
     *
     * Emitted when a folder becomes available
     **/
    signals[FOLDER_AVAILABLE] = g_signal_new (
        "folder-available",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_available),
        NULL, NULL, NULL,
        G_TYPE_NONE, 2,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING);

    /**
     * MailFolderCache::folder-unavailable
     * @store: the #CamelStore containing the folder
     * @folder_name: the name of the folder
     *
     * Emitted when a folder becomes unavailable.  This represents a
     * transient condition.  See MailFolderCache::folder-deleted to be
     * notified when a folder is permanently removed.
     **/
    signals[FOLDER_UNAVAILABLE] = g_signal_new (
        "folder-unavailable",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_unavailable),
        NULL, NULL, NULL,
        G_TYPE_NONE, 2,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING);

    /**
     * MailFolderCache::folder-deleted
     * @store: the #CamelStore containing the folder
     * @folder_name: the name of the folder
     *
     * Emitted when a folder is deleted
     **/
    signals[FOLDER_DELETED] = g_signal_new (
        "folder-deleted",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_deleted),
        NULL, NULL, /* accumulator */
        NULL,
        G_TYPE_NONE, 2,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING);

    /**
     * MailFolderCache::folder-renamed
     * @store: the #CamelStore containing the folder
     * @old_folder_name: the old name of the folder
     * @new_folder_name: the new name of the folder
     *
     * Emitted when a folder is renamed
     **/
    signals[FOLDER_RENAMED] = g_signal_new (
        "folder-renamed",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_renamed),
        NULL, NULL, NULL,
        G_TYPE_NONE, 3,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING,
        G_TYPE_STRING);

    /**
     * MailFolderCache::folder-unread-updated
     * @store: the #CamelStore containing the folder
     * @folder_name: the name of the folder
     * @unread: the number of unread mails in the folder
     *
     * Emitted when a we receive an update to the unread count for a folder
     **/
    signals[FOLDER_UNREAD_UPDATED] = g_signal_new (
        "folder-unread-updated",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_unread_updated),
        NULL, NULL, NULL,
        G_TYPE_NONE, 3,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING,
        G_TYPE_INT);

    /**
     * MailFolderCache::folder-changed
     * @store: the #CamelStore containing the folder
     * @folder_name: the name of the folder
     * @new_messages: the number of new messages for the folder
     * @msg_uid: uid of the new message, or NULL
     * @msg_sender: sender of the new message, or NULL
     * @msg_subject: subject of the new message, or NULL
     *
     * Emitted when a folder has changed.  If @new_messages is not
     * exactly 1, @msg_uid, @msg_sender, and @msg_subject will be NULL.
     **/
    signals[FOLDER_CHANGED] = g_signal_new (
        "folder-changed",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (MailFolderCacheClass, folder_changed),
        NULL, NULL, NULL,
        G_TYPE_NONE, 6,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING,
        G_TYPE_INT,
        G_TYPE_STRING,
        G_TYPE_STRING,
        G_TYPE_STRING);
}

static void
mail_folder_cache_init (MailFolderCache *cache)
{
    const gchar *buf;
    guint timeout;

    cache->priv = MAIL_FOLDER_CACHE_GET_PRIVATE (cache);

    /* initialize values */
    cache->priv->stores = g_hash_table_new (NULL, NULL);
    g_rec_mutex_init (&cache->priv->stores_mutex);

    g_queue_init (&cache->priv->updates);
    cache->priv->count_sent = getenv ("EVOLUTION_COUNT_SENT") != NULL;
    cache->priv->count_trash = getenv ("EVOLUTION_COUNT_TRASH") != NULL;

    buf = getenv ("EVOLUTION_PING_TIMEOUT");
    timeout = buf ? strtoul (buf, NULL, 10) : 600;
    cache->priv->ping_id = g_timeout_add_seconds (
        timeout, (GSourceFunc) ping_cb, cache);

    g_queue_init (&cache->priv->local_folder_uris);
    g_queue_init (&cache->priv->remote_folder_uris);
}

MailFolderCache *
mail_folder_cache_new (EMailSession *session)
{
    g_return_val_if_fail (E_IS_MAIL_SESSION (session), NULL);

    return g_object_new (
        MAIL_TYPE_FOLDER_CACHE,
        "session", session, NULL);
}

EMailSession *
mail_folder_cache_get_session (MailFolderCache *cache)
{
    g_return_val_if_fail (MAIL_IS_FOLDER_CACHE (cache), NULL);

    return E_MAIL_SESSION (cache->priv->session);
}

/**
 * mail_folder_cache_note_store:
 *
 * Add a store whose folders should appear in the shell The folders are scanned
 * from the store, and/or added at runtime via the folder_created event.  The
 * @done function returns if we can free folder info.
 */
void
mail_folder_cache_note_store (MailFolderCache *cache,
                              CamelStore *store,
                              GCancellable *cancellable,
                              NoteDoneFunc done,
                              gpointer data)
{
    CamelSession *session;
    StoreInfo *si;
    struct _update_data *ud;
    gint hook = 0;

    g_return_if_fail (MAIL_IS_FOLDER_CACHE (cache));
    g_return_if_fail (CAMEL_IS_STORE (store));

    session = camel_service_get_session (CAMEL_SERVICE (store));

    g_rec_mutex_lock (&cache->priv->stores_mutex);

    si = g_hash_table_lookup (cache->priv->stores, store);
    if (si == NULL) {
        si = store_info_new (store);
        g_hash_table_insert (cache->priv->stores, store, si);
        hook = TRUE;
    }

    ud = g_malloc0 (sizeof (*ud));
    ud->done = done;
    ud->data = data;
    ud->cache = cache;

    if (G_IS_CANCELLABLE (cancellable))
        ud->cancellable = g_object_ref (cancellable);

    /* We might get a race when setting up a store, such that it is
     * still left in offline mode, after we've gone online.  This
     * catches and fixes it up when the shell opens us. */
    if (CAMEL_IS_DISCO_STORE (store)) {
        if (camel_session_get_online (session) &&
             camel_disco_store_status (CAMEL_DISCO_STORE (store)) ==
            CAMEL_DISCO_STORE_OFFLINE) {
            e_mail_store_go_online (
                store, G_PRIORITY_DEFAULT, cancellable,
                (GAsyncReadyCallback) store_go_online_cb, ud);
        } else {
            goto normal_setup;
        }
    } else if (CAMEL_IS_OFFLINE_STORE (store)) {
        if (camel_session_get_online (session) &&
            !camel_offline_store_get_online (
            CAMEL_OFFLINE_STORE (store))) {
            e_mail_store_go_online (
                store, G_PRIORITY_DEFAULT, cancellable,
                (GAsyncReadyCallback) store_go_online_cb, ud);
        } else {
            goto normal_setup;
        }
    } else {
    normal_setup:
        if (store_has_folder_hierarchy (store))
            camel_store_get_folder_info (
                store, NULL,
                CAMEL_STORE_FOLDER_INFO_FAST |
                CAMEL_STORE_FOLDER_INFO_RECURSIVE |
                CAMEL_STORE_FOLDER_INFO_SUBSCRIBED,
                G_PRIORITY_DEFAULT, cancellable,
                (GAsyncReadyCallback) update_folders, ud);
    }

    g_queue_push_tail (&si->folderinfo_updates, ud);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    /* there is potential for race here, but it is safe as we check
     * for the store anyway */
    if (hook) {
        g_signal_connect (
            store, "folder-opened",
            G_CALLBACK (store_folder_opened_cb), cache);
        g_signal_connect (
            store, "folder-created",
            G_CALLBACK (store_folder_created_cb), cache);
        g_signal_connect (
            store, "folder-deleted",
            G_CALLBACK (store_folder_deleted_cb), cache);
        g_signal_connect (
            store, "folder-renamed",
            G_CALLBACK (store_folder_renamed_cb), cache);
    }

    if (hook && CAMEL_IS_SUBSCRIBABLE (store)) {
        g_signal_connect (
            store, "folder-subscribed",
            G_CALLBACK (store_folder_subscribed_cb), cache);
        g_signal_connect (
            store, "folder-unsubscribed",
            G_CALLBACK (store_folder_unsubscribed_cb), cache);
    }
}

/**
 * mail_folder_cache_note_folder:
 *
 * When a folder has been opened, notify it for watching.  The folder must have
 * already been created on the store (which has already been noted) before the
 * folder can be opened
 */
void
mail_folder_cache_note_folder (MailFolderCache *cache,
                               CamelFolder *folder)
{
    CamelStore *parent_store;
    StoreInfo *si;
    struct _folder_info *mfi;
    const gchar *full_name;

    g_return_if_fail (MAIL_IS_FOLDER_CACHE (cache));
    g_return_if_fail (CAMEL_IS_FOLDER (folder));

    full_name = camel_folder_get_full_name (folder);
    parent_store = camel_folder_get_parent_store (folder);

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    if (cache->priv->stores == NULL
        || (si = g_hash_table_lookup (cache->priv->stores, parent_store)) == NULL
        || (mfi = g_hash_table_lookup (si->folders, full_name)) == NULL) {
        w (g_warning ("Noting folder before store initialised"));
        g_rec_mutex_unlock (&cache->priv->stores_mutex);
        return;
    }

    /* dont do anything if we already have this */
    if (mfi->folder == folder) {
        g_rec_mutex_unlock (&cache->priv->stores_mutex);
        return;
    }

    mfi->folder = folder;

    g_object_add_weak_pointer (G_OBJECT (folder), &mfi->folder);

    update_1folder (cache, mfi, 0, NULL, NULL, NULL, NULL);

    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    g_signal_connect (
        folder, "changed",
        G_CALLBACK (folder_changed_cb), cache);
}

/**
 * mail_folder_cache_get_folder_from_uri:
 *
 * Gets the #CamelFolder for the supplied @uri.
 *
 * Returns: %TRUE if the URI is available, folderp is set to a reffed
 *          folder if the folder has also already been opened
 */
gboolean
mail_folder_cache_get_folder_from_uri (MailFolderCache *cache,
                                       const gchar *uri,
                                       CamelFolder **folderp)
{
    struct _find_info fi = { uri, NULL };

    if (cache->priv->stores == NULL)
        return FALSE;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    g_hash_table_foreach (
        cache->priv->stores, (GHFunc)
        storeinfo_find_folder_info, &fi);
    if (folderp) {
        if (fi.fi && fi.fi->folder)
            *folderp = g_object_ref (fi.fi->folder);
        else
            *folderp = NULL;
    }
    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    return fi.fi != NULL;
}

gboolean
mail_folder_cache_get_folder_info_flags (MailFolderCache *cache,
                                         CamelFolder *folder,
                                         CamelFolderInfoFlags *flags)
{
    struct _find_info fi = { NULL, NULL };
    gchar *folder_uri;

    if (cache->priv->stores == NULL)
        return FALSE;

    folder_uri = e_mail_folder_uri_from_folder (folder);
    fi.folder_uri = folder_uri;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    g_hash_table_foreach (
        cache->priv->stores, (GHFunc)
        storeinfo_find_folder_info, &fi);
    if (flags) {
        if (fi.fi)
            *flags = fi.fi->flags;
        else
            *flags = 0;
    }
    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    g_free (folder_uri);

    return fi.fi != NULL;
}

/* Returns whether folder 'folder' has children based on folder_info->child property.
 * If not found returns FALSE and sets 'found' to FALSE, if not NULL. */
gboolean
mail_folder_cache_get_folder_has_children (MailFolderCache *cache,
                                           CamelFolder *folder,
                                           gboolean *found)
{
    struct _find_info fi = { NULL, NULL };
    gchar *folder_uri;

    g_return_val_if_fail (MAIL_IS_FOLDER_CACHE (cache), FALSE);
    g_return_val_if_fail (CAMEL_IS_FOLDER (folder), FALSE);

    if (cache->priv->stores == NULL)
        return FALSE;

    folder_uri = e_mail_folder_uri_from_folder (folder);
    fi.folder_uri = folder_uri;

    g_rec_mutex_lock (&cache->priv->stores_mutex);
    g_hash_table_foreach (
        cache->priv->stores, (GHFunc)
        storeinfo_find_folder_info, &fi);
    if (found != NULL)
        *found = fi.fi != NULL;
    g_rec_mutex_unlock (&cache->priv->stores_mutex);

    g_free (folder_uri);

    return fi.fi != NULL && fi.fi->has_children;
}

void
mail_folder_cache_get_local_folder_uris (MailFolderCache *self,
                                         GQueue *out_queue)
{
    GList *head, *link;

    g_return_if_fail (MAIL_IS_FOLDER_CACHE (self));
    g_return_if_fail (out_queue != NULL);

    /* Reuse the stores mutex just because it's handy. */
    g_rec_mutex_lock (&self->priv->stores_mutex);

    head = g_queue_peek_head_link (&self->priv->local_folder_uris);

    for (link = head; link != NULL; link = g_list_next (link))
        g_queue_push_tail (out_queue, g_strdup (link->data));

    g_rec_mutex_unlock (&self->priv->stores_mutex);
}

void
mail_folder_cache_get_remote_folder_uris (MailFolderCache *self,
                                          GQueue *out_queue)
{
    GList *head, *link;

    g_return_if_fail (MAIL_IS_FOLDER_CACHE (self));
    g_return_if_fail (out_queue != NULL);

    /* Reuse the stores mutex just because it's handy. */
    g_rec_mutex_lock (&self->priv->stores_mutex);

    head = g_queue_peek_head_link (&self->priv->remote_folder_uris);

    for (link = head; link != NULL; link = g_list_next (link))
        g_queue_push_tail (out_queue, g_strdup (link->data));

    g_rec_mutex_unlock (&self->priv->stores_mutex);
}

void
mail_folder_cache_service_removed (MailFolderCache *cache,
                                   CamelService *service)
{
    StoreInfo *si;

    g_return_if_fail (MAIL_IS_FOLDER_CACHE (cache));
    g_return_if_fail (CAMEL_IS_SERVICE (service));

    if (cache->priv->stores == NULL)
        return;

    g_rec_mutex_lock (&cache->priv->stores_mutex);

    si = g_hash_table_lookup (cache->priv->stores, service);
    if (si != NULL) {
        g_hash_table_remove (cache->priv->stores, service);

        g_signal_handlers_disconnect_matched (
            service, G_SIGNAL_MATCH_DATA,
            0, 0, NULL, NULL, cache);

        g_hash_table_foreach (
            si->folders, (GHFunc)
            unset_folder_info_hash, cache);

        store_info_free (si);
    }

    g_rec_mutex_unlock (&cache->priv->stores_mutex);
}

void
mail_folder_cache_service_enabled (MailFolderCache *cache,
                                   CamelService *service)
{
    g_return_if_fail (MAIL_IS_FOLDER_CACHE (cache));
    g_return_if_fail (CAMEL_IS_SERVICE (service));

    mail_folder_cache_note_store (
        cache, CAMEL_STORE (service), NULL, NULL, NULL);
}

void
mail_folder_cache_service_disabled (MailFolderCache *cache,
                                    CamelService *service)
{
    g_return_if_fail (MAIL_IS_FOLDER_CACHE (cache));
    g_return_if_fail (CAMEL_IS_SERVICE (service));

    /* To the folder cache, disabling a service is the same as
     * removing it.  We keep a separate callback function only
     * to use as a breakpoint target in a debugger. */
    mail_folder_cache_service_removed (cache, service);
}