path: root/mail/em-folder-tree.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:
 *      Jeffrey Stedfast <fejj@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

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

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

#include <libxml/tree.h>

#include <glib/gi18n.h>
#include <gdk/gdkkeysyms.h>
#include <glib/gi18n.h>

#include "e-util/e-account-utils.h"
#include "e-util/e-mktemp.h"
#include "e-util/e-icon-factory.h"
#include "e-util/e-alert-dialog.h"
#include "e-util/e-util.h"

#include "misc/e-selectable.h"

#include "em-vfolder-rule.h"

#include "mail-mt.h"
#include "mail-ops.h"
#include "mail-tools.h"
#include "mail-send-recv.h"
#include "mail-vfolder.h"

#include "em-utils.h"
#include "em-folder-tree.h"
#include "em-folder-utils.h"
#include "em-folder-selector.h"
#include "em-folder-properties.h"
#include "em-event.h"

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

#define d(x)

struct _selected_uri {
    gchar *key;     /* store:path or account/path */
    gchar *uri;
    CamelService *service;
    gchar *path;
};

struct _EMFolderTreePrivate {
    EMailSession *session;

    /* selected_uri structures of each path pending selection. */
    GSList *select_uris;

    /* Removed as they're encountered, so use this
     * to find URI's not presnet but selected. */
    GHashTable *select_uris_table;

    guint32 excluded;
    gboolean    (*excluded_func)    (EMFolderTree *folder_tree,
                         GtkTreeModel *model,
                         GtkTreeIter *iter,
                         gpointer data);
    gpointer excluded_data;

    guint cursor_set:1; /* set to TRUE means we or something
                 * else has set the cursor, otherwise
                 * we need to set it when we set the
                 * selection */

    guint autoscroll_id;
    guint autoexpand_id;
    GtkTreeRowReference *autoexpand_row;

    guint loading_row_id;
    guint loaded_row_id;

    GtkTreeRowReference *drag_row;
    gboolean skip_double_click;

    GtkCellRenderer *text_renderer;
    PangoEllipsizeMode ellipsize;

    GtkWidget *selectable; /* an ESelectable, where to pass selectable calls */

    /* Signal handler IDs */
    gulong selection_changed_handler_id;
};

enum {
    PROP_0,
    PROP_COPY_TARGET_LIST,
    PROP_ELLIPSIZE,
    PROP_PASTE_TARGET_LIST,
    PROP_SESSION
};

enum {
    FOLDER_ACTIVATED,  /* aka double-clicked or user hit enter */
    FOLDER_SELECTED,
    POPUP_EVENT,
    HIDDEN_KEY_EVENT,
    LAST_SIGNAL
};

/* Drag & Drop types */
enum DndDragType {
    DND_DRAG_TYPE_FOLDER,          /* drag an evo folder */
    DND_DRAG_TYPE_TEXT_URI_LIST,   /* drag to an mbox file */
    NUM_DRAG_TYPES
};

enum DndDropType {
    DND_DROP_TYPE_UID_LIST,        /* drop a list of message uids */
    DND_DROP_TYPE_FOLDER,          /* drop an evo folder */
    DND_DROP_TYPE_MESSAGE_RFC822,  /* drop a message/rfc822 stream */
    DND_DROP_TYPE_TEXT_URI_LIST,   /* drop an mbox file */
    NUM_DROP_TYPES
};

static GtkTargetEntry drag_types[] = {
    { (gchar *) "x-folder",         0, DND_DRAG_TYPE_FOLDER         },
    { (gchar *) "text/uri-list",    0, DND_DRAG_TYPE_TEXT_URI_LIST  },
};

static GtkTargetEntry drop_types[] = {
    { (gchar *) "x-uid-list" ,      0, DND_DROP_TYPE_UID_LIST       },
    { (gchar *) "x-folder",         0, DND_DROP_TYPE_FOLDER         },
    { (gchar *) "message/rfc822",   0, DND_DROP_TYPE_MESSAGE_RFC822 },
    { (gchar *) "text/uri-list",    0, DND_DROP_TYPE_TEXT_URI_LIST  },
};

static GdkAtom drag_atoms[NUM_DRAG_TYPES];
static GdkAtom drop_atoms[NUM_DROP_TYPES];

static guint signals[LAST_SIGNAL] = { 0 };

extern CamelStore *vfolder_store;

struct _folder_tree_selection_data {
    GtkTreeModel *model;
    GtkTreeIter *iter;
    gboolean set;
};

static gpointer parent_class = NULL;

struct _EMFolderTreeGetFolderInfo {
    MailMsg base;

    /* input data */
    GtkTreeRowReference *root;
    EMFolderTree *folder_tree;
    CamelStore *store;
    guint32 flags;
    gchar *top;

    /* output data */
    CamelFolderInfo *fi;
};

static gchar *
folder_tree_get_folder_info__desc (struct _EMFolderTreeGetFolderInfo *m)
{
    gchar *ret, *name;

    name = camel_service_get_name ((CamelService *) m->store, TRUE);
    ret = g_strdup_printf(_("Scanning folders in \"%s\""), name);
    g_free (name);
    return ret;
}

static void
folder_tree_get_folder_info__exec (struct _EMFolderTreeGetFolderInfo *m,
                                   GCancellable *cancellable,
                                   GError **error)
{
    guint32 flags = m->flags | CAMEL_STORE_FOLDER_INFO_SUBSCRIBED;
    GError *local_error = NULL;

    m->fi = camel_store_get_folder_info_sync (
        m->store, m->top, flags, cancellable, &local_error);

    /* XXX POP3 stores always return an error because they have
     *     no folder hierarchy to scan.  Clear that error so the
     *     user doesn't see it. */
    if (g_error_matches (local_error,
        CAMEL_STORE_ERROR, CAMEL_STORE_ERROR_NO_FOLDER))
        g_error_free (local_error);
    else if (local_error != NULL)
        g_propagate_error (error, local_error);
}

static void
folder_tree_get_folder_info__done (struct _EMFolderTreeGetFolderInfo *m)
{
    struct _EMFolderTreeModelStoreInfo *si;
    GtkTreeIter root, iter, titer;
    CamelFolderInfo *fi;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GtkTreePath *path;
    gboolean is_store, need_add_node;

    /* check that we haven't been destroyed */
    g_return_if_fail (GTK_IS_TREE_VIEW (m->folder_tree));

    /* check that our parent folder hasn't been deleted/unsubscribed */
    if (!gtk_tree_row_reference_valid (m->root))
        return;

    tree_view = GTK_TREE_VIEW (m->folder_tree);
    model = gtk_tree_view_get_model (tree_view);

    si = em_folder_tree_model_lookup_store_info (
        EM_FOLDER_TREE_MODEL (model), m->store);
    if (si == NULL) {
        /* store has been removed in the interim - do nothing */
        return;
    }

    path = gtk_tree_row_reference_get_path (m->root);
    gtk_tree_model_get_iter (model, &root, path);

    /* If we had an error, then we need to re-set the
     * load subdirs state and collapse the node. */
    if (!m->fi && m->base.error != NULL) {
        gtk_tree_store_set (
            GTK_TREE_STORE (model), &root,
            COL_BOOL_LOAD_SUBDIRS, TRUE, -1);
        gtk_tree_view_collapse_row (tree_view, path);
        gtk_tree_path_free (path);
        return;
    }

    gtk_tree_path_free (path);

    /* make sure we still need to load the tree subfolders... */
    gtk_tree_model_get (model, &root, COL_BOOL_IS_STORE, &is_store, -1);

    /* get the first child (which will be a dummy node) */
    gtk_tree_model_iter_children (model, &iter, &root);

    need_add_node = TRUE;

    /* Traverse to the last valid iter, or the "Loading..." node */
    do {
        gboolean is_store_node = FALSE, is_folder_node = FALSE;

        titer = iter; /* Preserve the last valid iter */

        gtk_tree_model_get (
            model, &iter, COL_BOOL_IS_STORE, &is_store_node,
            COL_BOOL_IS_FOLDER, &is_folder_node, -1);

        /* stop on a "Loading..." node */
        if (!is_store_node && !is_folder_node) {
            /* remember it found a "Loading..." node and overwrite or remove it later */
            need_add_node = FALSE;
            break;
        }

    } while (gtk_tree_model_iter_next (model, &iter));

    iter = titer;

    /* FIXME: camel's IMAP code is totally on crack here, @top's
     * folder info should be @fi and fi->child should be what we
     * want to fill our tree with... *sigh* */
    if (m->top && m->fi && !strcmp (m->fi->full_name, m->top)) {
        if (!(fi = m->fi->child))
            fi = m->fi->next;
    } else
        fi = m->fi;

    if (fi == NULL) {
        /* no children afterall... remove the "Loading..." placeholder node */
        if (!need_add_node)
            gtk_tree_store_remove (GTK_TREE_STORE (model), &iter);

        if (is_store) {
            path = gtk_tree_model_get_path (model, &root);
            gtk_tree_view_collapse_row (tree_view, path);
            gtk_tree_path_free (path);
            return;
        }
    } else {
        gint fully_loaded;

        fully_loaded =
            ((m->flags & CAMEL_STORE_FOLDER_INFO_RECURSIVE) != 0);

        do {
            if (g_hash_table_lookup (si->full_hash, fi->full_name) == NULL) {
                if (need_add_node)
                    gtk_tree_store_append (GTK_TREE_STORE (model), &iter, &root);
                need_add_node = TRUE;

                em_folder_tree_model_set_folder_info (
                    EM_FOLDER_TREE_MODEL (model),
                    &iter, si, fi, fully_loaded);
            }

            fi = fi->next;
        } while (fi != NULL);

        /* all children are known, remove the "Loading..." node */
        if (!need_add_node)
            gtk_tree_store_remove (GTK_TREE_STORE (model), &iter);
    }

    gtk_tree_store_set (
        GTK_TREE_STORE (model), &root,
        COL_BOOL_LOAD_SUBDIRS, FALSE, -1);
}

static void
folder_tree_get_folder_info__free (struct _EMFolderTreeGetFolderInfo *m)
{
    camel_store_free_folder_info (m->store, m->fi);

    gtk_tree_row_reference_free (m->root);
    g_object_unref (m->folder_tree);
    g_object_unref (m->store);
    g_free (m->top);
}

static MailMsgInfo get_folder_info_info = {
    sizeof (struct _EMFolderTreeGetFolderInfo),
    (MailMsgDescFunc) folder_tree_get_folder_info__desc,
    (MailMsgExecFunc) folder_tree_get_folder_info__exec,
    (MailMsgDoneFunc) folder_tree_get_folder_info__done,
    (MailMsgFreeFunc) folder_tree_get_folder_info__free
};

static void
folder_tree_emit_popup_event (EMFolderTree *folder_tree,
                              GdkEvent *event)
{
    g_signal_emit (folder_tree, signals[POPUP_EVENT], 0, event);
}

static void
folder_tree_free_select_uri (struct _selected_uri *u)
{
    g_free (u->uri);
    if (u->service)
        g_object_unref (u->service);
    g_free (u->key);
    g_free (u->path);
    g_free (u);
}

static gboolean
folder_tree_select_func (GtkTreeSelection *selection,
                         GtkTreeModel *model,
                         GtkTreePath *path,
                         gboolean selected)
{
    EMFolderTreePrivate *priv;
    GtkTreeView *tree_view;
    gboolean is_store;
    guint32 flags;
    GtkTreeIter iter;

    tree_view = gtk_tree_selection_get_tree_view (selection);

    priv = EM_FOLDER_TREE (tree_view)->priv;

    if (selected)
        return TRUE;

    if (priv->excluded == 0 && priv->excluded_func == NULL)
        return TRUE;

    if (!gtk_tree_model_get_iter (model, &iter, path))
        return TRUE;

    if (priv->excluded_func != NULL)
        return priv->excluded_func (
            EM_FOLDER_TREE (tree_view), model,
            &iter, priv->excluded_data);

    gtk_tree_model_get (
        model, &iter, COL_UINT_FLAGS, &flags,
        COL_BOOL_IS_STORE, &is_store, -1);

    if (is_store)
        flags |= CAMEL_FOLDER_NOSELECT;

    return (flags & priv->excluded) == 0;
}

/* NOTE: Removes and frees the selected uri structure */
static void
folder_tree_select_uri (EMFolderTree *folder_tree,
                        GtkTreePath *path,
                        struct _selected_uri *u)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);
    gtk_tree_selection_select_path (selection, path);
    if (!priv->cursor_set) {
        gtk_tree_view_set_cursor (tree_view, path, NULL, FALSE);
        priv->cursor_set = TRUE;
    }
    gtk_tree_view_scroll_to_cell (tree_view, path, NULL, TRUE, 0.8f, 0.0f);
    g_hash_table_remove (priv->select_uris_table, u->key);
    priv->select_uris = g_slist_remove (priv->select_uris, u);
    folder_tree_free_select_uri (u);
}

static void
folder_tree_expand_node (const gchar *key,
                         EMFolderTree *folder_tree)
{
    struct _EMFolderTreeModelStoreInfo *si;
    GtkTreeRowReference *row;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GtkTreePath *path;
    EAccount *account;
    EMailSession *session;
    CamelStore *store;
    const gchar *p;
    gchar *uid;
    gsize n;
    struct _selected_uri *u;

    if (!(p = strchr (key, '/')))
        n = strlen (key);
    else
        n = (p - key);

    uid = g_alloca (n + 1);
    memcpy (uid, key, n);
    uid[n] = '\0';

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = gtk_tree_view_get_model (tree_view);

    session = em_folder_tree_get_session (folder_tree);

    if ((account = e_get_account_by_uid (uid)) && account->enabled) {
        store = (CamelStore *) camel_session_get_service (
            CAMEL_SESSION (session), account->uid);

        if (store == NULL)
            return;

        g_object_ref (store);
    } else if (!strcmp (uid, "vfolder")) {
        if (!(store = vfolder_store))
            return;

        g_object_ref (store);
    } else if (!strcmp (uid, "local")) {
        if (!(store = e_mail_local_get_store ()))
            return;

        g_object_ref (store);
    } else {
        return;
    }

    si = em_folder_tree_model_lookup_store_info (
        EM_FOLDER_TREE_MODEL (model), store);
    if (si == NULL) {
        g_object_unref (store);
        return;
    }

    g_object_unref (store);

    if (p != NULL) {
        if (!(row = g_hash_table_lookup (si->full_hash, p + 1)))
            return;
    } else
        row = si->row;

    path = gtk_tree_row_reference_get_path (row);
    gtk_tree_view_expand_to_path (tree_view, path);

    u = g_hash_table_lookup (folder_tree->priv->select_uris_table, key);
    if (u)
        folder_tree_select_uri (folder_tree, path, u);

    gtk_tree_path_free (path);
}

static void
folder_tree_maybe_expand_row (EMFolderTreeModel *model,
                              GtkTreePath *tree_path,
                              GtkTreeIter *iter,
                              EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    struct _EMFolderTreeModelStoreInfo *si;
    gboolean is_store;
    CamelStore *store;
    EAccount *account;
    gchar *full_name;
    gchar *key;
    struct _selected_uri *u;

    gtk_tree_model_get ((GtkTreeModel *) model, iter,
                COL_STRING_FULL_NAME, &full_name,
                COL_POINTER_CAMEL_STORE, &store,
                COL_BOOL_IS_STORE, &is_store,
                -1);

    si = em_folder_tree_model_lookup_store_info (model, store);
    if ((account = e_get_account_by_name (si->display_name))) {
        key = g_strdup_printf ("%s/%s", account->uid, full_name ? full_name : "");
    } else if (CAMEL_IS_VEE_STORE (store)) {
        /* vfolder store */
        key = g_strdup_printf ("vfolder/%s", full_name ? full_name : "");
    } else {
        /* local store */
        key = g_strdup_printf ("local/%s", full_name ? full_name : "");
    }

    u = g_hash_table_lookup (priv->select_uris_table, key);
    if (u) {
        gchar *c = strrchr (key, '/');

        *c = '\0';
        folder_tree_expand_node (key, folder_tree);

        folder_tree_select_uri (folder_tree, tree_path, u);
    }

    g_free (full_name);
    g_free (key);
}

static void
folder_tree_clear_selected_list (EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;

    g_slist_foreach (priv->select_uris, (GFunc) folder_tree_free_select_uri, NULL);
    g_slist_free (priv->select_uris);
    g_hash_table_destroy (priv->select_uris_table);
    priv->select_uris = NULL;
    priv->select_uris_table = g_hash_table_new (g_str_hash, g_str_equal);
    priv->cursor_set = FALSE;
}

static void
folder_tree_cell_edited_cb (EMFolderTree *folder_tree,
                            const gchar *path_string,
                            const gchar *new_name)
{
    CamelFolderInfo *folder_info;
    CamelStore *store;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GtkTreePath *path;
    GtkTreeIter iter;
    gchar *old_name = NULL;
    gchar *old_full_name = NULL;
    gchar *new_full_name = NULL;
    gchar **strv;
    gpointer parent;
    guint index;
    GError *local_error = NULL;

    /* XXX Consider splitting this into separate async functions:
     *     em_folder_tree_rename_folder_async()
     *     em_folder_tree_rename_folder_finish() */

    parent = gtk_widget_get_toplevel (GTK_WIDGET (folder_tree));
    parent = gtk_widget_is_toplevel (parent) ? parent : NULL;

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = gtk_tree_view_get_model (tree_view);
    path = gtk_tree_path_new_from_string (path_string);
    gtk_tree_model_get_iter (model, &iter, path);
    gtk_tree_path_free (path);

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_STRING_DISPLAY_NAME, &old_name,
        COL_STRING_FULL_NAME, &old_full_name, -1);

    if (!old_name || !old_full_name || g_strcmp0 (new_name, old_name) == 0)
        goto exit;

    /* Check for invalid characters. */
    if (strchr (new_name, '/') != NULL) {
        e_alert_run_dialog_for_args (
            parent, "mail:no-rename-folder",
            old_name, new_name,
            _("Folder names cannot contain '/'"), NULL);
        goto exit;
    }

    /* Build the new name from the old name. */
    strv = g_strsplit_set (old_full_name, "/", 0);
    index = g_strv_length (strv) - 1;
    g_free (strv[index]);
    strv[index] = g_strdup (new_name);
    new_full_name = g_strjoinv ("/", strv);
    g_strfreev (strv);

    /* Check for duplicate folder name. */
    /* FIXME camel_store_get_folder_info() may block. */
    folder_info = camel_store_get_folder_info_sync (
        store, new_full_name,
        CAMEL_STORE_FOLDER_INFO_FAST, NULL, NULL);
    if (folder_info != NULL) {
        e_alert_run_dialog_for_args (
            parent, "mail:no-rename-folder-exists",
            old_name, new_name, NULL);
        camel_store_free_folder_info (store, folder_info);
        goto exit;
    }

    /* FIXME camel_store_rename_folder_sync() may block. */
    if (!camel_store_rename_folder_sync (
        store, old_full_name, new_full_name, NULL, &local_error)) {
        e_alert_run_dialog_for_args (
            parent, "mail:no-rename-folder",
            old_full_name, new_full_name,
            local_error ? local_error->message : _("Unknown error"), NULL);
        if (local_error)
            g_clear_error (&local_error);
        goto exit;
    }

exit:

    g_free (old_name);
    g_free (old_full_name);
    g_free (new_full_name);
}

static void
folder_tree_selection_changed_cb (EMFolderTree *folder_tree,
                                  GtkTreeSelection *selection)
{
    GtkTreeModel *model;
    GtkTreeIter iter;
    GList *list;
    CamelStore *store = NULL;
    CamelFolderInfoFlags flags = 0;
    guint unread = 0;
    guint old_unread = 0;
    gchar *folder_name = NULL;

    list = gtk_tree_selection_get_selected_rows (selection, &model);

    if (list == NULL)
        goto exit;

    gtk_tree_model_get_iter (model, &iter, list->data);

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_STRING_FULL_NAME, &folder_name,
        COL_UINT_FLAGS, &flags,
        COL_UINT_UNREAD, &unread,
        COL_UINT_UNREAD_LAST_SEL, &old_unread, -1);

    /* Sync unread counts to distinguish new incoming mail. */
    if (unread != old_unread)
        gtk_tree_store_set (
            GTK_TREE_STORE (model), &iter,
            COL_UINT_UNREAD_LAST_SEL, unread, -1);

exit:
    g_signal_emit (
        folder_tree, signals[FOLDER_SELECTED], 0,
        store, folder_name, flags);

    g_free (folder_name);

    g_list_foreach (list, (GFunc) gtk_tree_path_free, NULL);
    g_list_free (list);
}

static void
folder_tree_set_session (EMFolderTree *folder_tree,
                         EMailSession *session)
{
    g_return_if_fail (CAMEL_IS_SESSION (session));
    g_return_if_fail (folder_tree->priv->session == NULL);

    folder_tree->priv->session = g_object_ref (session);
}

static GtkTargetList *
folder_tree_get_copy_target_list (EMFolderTree *folder_tree)
{
    GtkTargetList *target_list = NULL;

    if (E_IS_SELECTABLE (folder_tree->priv->selectable)) {
        ESelectable *selectable;

        selectable = E_SELECTABLE (folder_tree->priv->selectable);
        target_list = e_selectable_get_copy_target_list (selectable);
    }

    return target_list;
}

static GtkTargetList *
folder_tree_get_paste_target_list (EMFolderTree *folder_tree)
{
    GtkTargetList *target_list = NULL;

    if (E_IS_SELECTABLE (folder_tree->priv->selectable)) {
        ESelectable *selectable;

        selectable = E_SELECTABLE (folder_tree->priv->selectable);
        target_list = e_selectable_get_paste_target_list (selectable);
    }

    return target_list;
}

static void
folder_tree_set_property (GObject *object,
                          guint property_id,
                          const GValue *value,
                          GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_ELLIPSIZE:
            em_folder_tree_set_ellipsize (
                EM_FOLDER_TREE (object),
                g_value_get_enum (value));
            return;

        case PROP_SESSION:
            folder_tree_set_session (
                EM_FOLDER_TREE (object),
                g_value_get_object (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
folder_tree_get_property (GObject *object,
                          guint property_id,
                          GValue *value,
                          GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_COPY_TARGET_LIST:
            g_value_set_boxed (
                value,
                folder_tree_get_copy_target_list (
                EM_FOLDER_TREE (object)));
            return;

        case PROP_ELLIPSIZE:
            g_value_set_enum (
                value,
                em_folder_tree_get_ellipsize (
                EM_FOLDER_TREE (object)));
            return;

        case PROP_PASTE_TARGET_LIST:
            g_value_set_boxed (
                value,
                folder_tree_get_paste_target_list (
                EM_FOLDER_TREE (object)));
            return;

        case PROP_SESSION:
            g_value_set_object (
                value,
                em_folder_tree_get_session (
                EM_FOLDER_TREE (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
folder_tree_dispose (GObject *object)
{
    EMFolderTreePrivate *priv;
    GtkTreeModel *model;

    priv = EM_FOLDER_TREE (object)->priv;
    model = gtk_tree_view_get_model (GTK_TREE_VIEW (object));

    if (priv->loaded_row_id != 0) {
        g_signal_handler_disconnect (model, priv->loaded_row_id);
        priv->loaded_row_id = 0;
    }

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

    if (priv->autoexpand_id != 0) {
        gtk_tree_row_reference_free (priv->autoexpand_row);
        priv->autoexpand_row = NULL;

        g_source_remove (priv->autoexpand_id);
        priv->autoexpand_id = 0;
    }

    if (priv->session != NULL) {
        g_object_unref (priv->session);
        priv->session = NULL;
    }

    if (priv->text_renderer != NULL) {
        g_object_unref (priv->text_renderer);
        priv->text_renderer = NULL;
    }

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

static void
folder_tree_finalize (GObject *object)
{
    EMFolderTreePrivate *priv;

    priv = EM_FOLDER_TREE (object)->priv;

    if (priv->select_uris != NULL) {
        g_slist_foreach (
            priv->select_uris,
            (GFunc) folder_tree_free_select_uri, NULL);
        g_slist_free (priv->select_uris);
        g_hash_table_destroy (priv->select_uris_table);
        priv->select_uris = NULL;
    }

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

static gboolean
folder_tree_button_press_event (GtkWidget *widget,
                                GdkEventButton *event)
{
    EMFolderTreePrivate *priv;
    GtkWidgetClass *widget_class;
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;
    GtkTreePath *path;
    gulong handler_id;

    priv = EM_FOLDER_TREE (widget)->priv;

    tree_view = GTK_TREE_VIEW (widget);
    selection = gtk_tree_view_get_selection (tree_view);

    if (gtk_tree_selection_get_mode (selection) == GTK_SELECTION_SINGLE)
        folder_tree_clear_selected_list (EM_FOLDER_TREE (widget));

    priv->cursor_set = TRUE;

    if (event->button != 3)
        goto chainup;

    if (!gtk_tree_view_get_path_at_pos (
        tree_view, event->x, event->y,
        &path, NULL, NULL, NULL))
        goto chainup;

    /* Select and focus the row that was right-clicked, but prevent
     * a "folder-selected" signal emission since this does not count
     * as a folder selection in the sense we mean. */
    handler_id = priv->selection_changed_handler_id;
    g_signal_handler_block (selection, handler_id);
    gtk_tree_selection_select_path (selection, path);
    gtk_tree_view_set_cursor (tree_view, path, NULL, FALSE);
    g_signal_handler_unblock (selection, handler_id);

    gtk_tree_path_free (path);

    folder_tree_emit_popup_event (
        EM_FOLDER_TREE (tree_view), (GdkEvent *) event);

chainup:

    /* Chain up to parent's button_press_event() method. */
    widget_class = GTK_WIDGET_CLASS (parent_class);
    return widget_class->button_press_event (widget, event);
}

static gboolean
folder_tree_key_press_event (GtkWidget *widget,
                             GdkEventKey *event)
{
    EMFolderTreePrivate *priv;
    GtkWidgetClass *widget_class;
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;

    if (event && event->type == GDK_KEY_PRESS &&
        (event->keyval == GDK_KEY_space ||
         event->keyval == '.' ||
         event->keyval == ',' ||
         event->keyval == '[' ||
         event->keyval == ']')) {
        g_signal_emit (widget, signals[HIDDEN_KEY_EVENT], 0, event);

        return TRUE;
    }

    priv = EM_FOLDER_TREE (widget)->priv;

    tree_view = GTK_TREE_VIEW (widget);
    selection = gtk_tree_view_get_selection (tree_view);

    if (gtk_tree_selection_get_mode (selection) == GTK_SELECTION_SINGLE)
        folder_tree_clear_selected_list (EM_FOLDER_TREE (widget));

    priv->cursor_set = TRUE;

    /* Chain up to parent's key_press_event() method. */
    widget_class = GTK_WIDGET_CLASS (parent_class);
    return widget_class->key_press_event (widget, event);
}

static gboolean
folder_tree_popup_menu (GtkWidget *widget)
{
    folder_tree_emit_popup_event (EM_FOLDER_TREE (widget), NULL);

    return TRUE;
}

static void
folder_tree_row_activated (GtkTreeView *tree_view,
                           GtkTreePath *path,
                           GtkTreeViewColumn *column)
{
    EMFolderTreePrivate *priv;
    GtkTreeModel *model;
    gchar *folder_name;
    GtkTreeIter iter;
    CamelStore *store;
    CamelFolderInfoFlags flags;

    priv = EM_FOLDER_TREE (tree_view)->priv;

    model = gtk_tree_view_get_model (tree_view);

    if (priv->skip_double_click)
        return;

    if (!gtk_tree_model_get_iter (model, &iter, path))
        return;

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_STRING_FULL_NAME, &folder_name,
        COL_UINT_FLAGS, &flags, -1);

    folder_tree_clear_selected_list (EM_FOLDER_TREE (tree_view));

    g_signal_emit (
        tree_view, signals[FOLDER_SELECTED], 0,
        store, folder_name, flags);

    g_signal_emit (
        tree_view, signals[FOLDER_ACTIVATED], 0,
        store, folder_name);

    g_free (folder_name);
}

static gboolean
folder_tree_test_collapse_row (GtkTreeView *tree_view,
                               GtkTreeIter *iter,
                               GtkTreePath *path)
{
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter cursor;

    selection = gtk_tree_view_get_selection (tree_view);

    if (!gtk_tree_selection_get_selected (selection, &model, &cursor))
        goto exit;

    /* Select the collapsed node IFF it is a
     * parent of the currently selected folder. */
    if (gtk_tree_store_is_ancestor (GTK_TREE_STORE (model), iter, &cursor))
        gtk_tree_view_set_cursor (tree_view, path, NULL, FALSE);

exit:
    return FALSE;
}

static void
folder_tree_row_expanded (GtkTreeView *tree_view,
                          GtkTreeIter *iter,
                          GtkTreePath *path)
{
    struct _EMFolderTreeGetFolderInfo *msg;
    GtkTreeModel *model;
    CamelStore *store;
    gchar *full_name;
    gboolean load;

    model = gtk_tree_view_get_model (tree_view);

    gtk_tree_model_get (
        model, iter,
        COL_STRING_FULL_NAME, &full_name,
        COL_POINTER_CAMEL_STORE, &store,
        COL_BOOL_LOAD_SUBDIRS, &load, -1);

    if (!load) {
        g_free (full_name);
        return;
    }

    gtk_tree_store_set (
        GTK_TREE_STORE (model), iter,
        COL_BOOL_LOAD_SUBDIRS, FALSE, -1);

    msg = mail_msg_new (&get_folder_info_info);
    msg->root = gtk_tree_row_reference_new (model, path);
    g_object_ref (store);
    msg->store = store;
    msg->folder_tree = g_object_ref (tree_view);
    msg->top = full_name;
    msg->flags =
        CAMEL_STORE_FOLDER_INFO_RECURSIVE |
        CAMEL_STORE_FOLDER_INFO_FAST;

    mail_msg_unordered_push (msg);
}

static void
folder_tree_class_init (EMFolderTreeClass *class)
{
    GObjectClass *object_class;
    GtkWidgetClass *widget_class;
    GtkTreeViewClass *tree_view_class;

    parent_class = g_type_class_peek_parent (class);
    g_type_class_add_private (class, sizeof (EMFolderTreePrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = folder_tree_set_property;
    object_class->get_property = folder_tree_get_property;
    object_class->dispose = folder_tree_dispose;
    object_class->finalize = folder_tree_finalize;

    widget_class = GTK_WIDGET_CLASS (class);
    widget_class->button_press_event = folder_tree_button_press_event;
    widget_class->key_press_event = folder_tree_key_press_event;
    widget_class->popup_menu = folder_tree_popup_menu;

    tree_view_class = GTK_TREE_VIEW_CLASS (class);
    tree_view_class->row_activated = folder_tree_row_activated;
    tree_view_class->test_collapse_row = folder_tree_test_collapse_row;
    tree_view_class->row_expanded = folder_tree_row_expanded;

    /* Inherited from ESelectableInterface */
    g_object_class_override_property (
        object_class,
        PROP_COPY_TARGET_LIST,
        "copy-target-list");

    g_object_class_install_property (
        object_class,
        PROP_ELLIPSIZE,
        g_param_spec_enum (
            "ellipsize",
            NULL,
            NULL,
            PANGO_TYPE_ELLIPSIZE_MODE,
            PANGO_ELLIPSIZE_NONE,
            G_PARAM_READWRITE));

    /* Inherited from ESelectableInterface */
    g_object_class_override_property (
        object_class,
        PROP_PASTE_TARGET_LIST,
        "paste-target-list");

    g_object_class_install_property (
        object_class,
        PROP_SESSION,
        g_param_spec_object (
            "session",
            NULL,
            NULL,
            E_TYPE_MAIL_SESSION,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT_ONLY));

    signals[FOLDER_SELECTED] = g_signal_new (
        "folder-selected",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (EMFolderTreeClass, folder_selected),
        NULL, NULL,
        e_marshal_VOID__OBJECT_STRING_UINT,
        G_TYPE_NONE, 3,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING,
        G_TYPE_UINT);

    signals[FOLDER_ACTIVATED] = g_signal_new (
        "folder-activated",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (EMFolderTreeClass, folder_activated),
        NULL, NULL,
        e_marshal_VOID__OBJECT_STRING,
        G_TYPE_NONE, 2,
        CAMEL_TYPE_STORE,
        G_TYPE_STRING);

    signals[POPUP_EVENT] = g_signal_new (
        "popup-event",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_FIRST | G_SIGNAL_ACTION,
        G_STRUCT_OFFSET (EMFolderTreeClass, popup_event),
        NULL, NULL,
        g_cclosure_marshal_VOID__BOXED,
        G_TYPE_NONE, 1,
        GDK_TYPE_EVENT | G_SIGNAL_TYPE_STATIC_SCOPE);

    signals[HIDDEN_KEY_EVENT] = g_signal_new (
        "hidden-key-event",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (EMFolderTreeClass, hidden_key_event),
        NULL, NULL,
        g_cclosure_marshal_VOID__BOXED,
        G_TYPE_NONE, 1,
        GDK_TYPE_EVENT | G_SIGNAL_TYPE_STATIC_SCOPE);
}

static gboolean
subdirs_contain_unread (GtkTreeModel *model, GtkTreeIter *root)
{
    guint unread;
    GtkTreeIter iter;

    if (!gtk_tree_model_iter_children (model, &iter, root))
        return FALSE;

    do {
        gtk_tree_model_get (model, &iter, COL_UINT_UNREAD, &unread, -1);
        if (unread)
            return TRUE;

        if (gtk_tree_model_iter_has_child (model, &iter))
            if (subdirs_contain_unread (model, &iter))
                return TRUE;
    } while (gtk_tree_model_iter_next (model, &iter));

    return FALSE;
}

static void
render_display_name (GtkTreeViewColumn *column, GtkCellRenderer *renderer,
             GtkTreeModel *model, GtkTreeIter *iter, gpointer user_data)
{
    gboolean is_store, bold, subdirs_unread = FALSE;
    gboolean editable;
    guint unread;
    gchar *display;
    gchar *name;

    gtk_tree_model_get (model, iter, COL_STRING_DISPLAY_NAME, &name,
                COL_BOOL_IS_STORE, &is_store,
                COL_UINT_UNREAD, &unread, -1);

    g_object_get (renderer, "editable", &editable, NULL);

    bold = is_store || unread;

    if (gtk_tree_model_iter_has_child (model, iter)) {
        gboolean expanded = TRUE;

        g_object_get (renderer, "is-expanded", &expanded, NULL);

        if (!bold || !expanded)
            subdirs_unread = subdirs_contain_unread (model, iter);
    }

    bold = !editable && (bold || subdirs_unread);

    if (!is_store && !editable && unread) {
        /* Translators: This is the string used for displaying the
         * folder names in folder trees. The first "%s" will be
         * replaced by the folder's name and "%u" will be replaced
         * with the number of unread messages in the folder. The
         * second %s will be replaced with a "+" letter for collapsed
         * folders with unread messages in some subfolder too,
         * or with an empty string for other cases.
         *
         * Most languages should translate this as "%s (%u%s)". The
         * languages that use localized digits (like Persian) may
         * need to replace "%u" with "%Iu". Right-to-left languages
         * (like Arabic and Hebrew) may need to add bidirectional
         * formatting codes to take care of the cases the folder
         * name appears in either direction.
         *
         * Do not translate the "folder-display|" part. Remove it
         * from your translation.
         */
        display = g_strdup_printf (
            C_("folder-display", "%s (%u%s)"),
            name, unread, subdirs_unread ? "+" : "");
        g_free (name);
    } else
        display = name;

    g_object_set (renderer, "text", display,
              "weight", bold ? PANGO_WEIGHT_BOLD : PANGO_WEIGHT_NORMAL,
              NULL);

    g_free (display);
}

static void
render_icon (GtkTreeViewColumn *column,
             GtkCellRenderer *renderer,
             GtkTreeModel *model,
             GtkTreeIter *iter)
{
    GtkTreeSelection *selection;
    GtkTreePath *drag_dest_row;
    GtkWidget *tree_view;
    GIcon *icon;
    guint unread;
    guint old_unread;
    gchar *icon_name;
    gboolean is_selected;
    gboolean is_drafts = FALSE;
    gboolean is_drag_dest = FALSE;

    gtk_tree_model_get (
        model, iter,
        COL_STRING_ICON_NAME, &icon_name,
        COL_UINT_UNREAD_LAST_SEL, &old_unread,
        COL_UINT_UNREAD, &unread,
        COL_BOOL_IS_DRAFT, &is_drafts,
        -1);

    if (icon_name == NULL)
        return;

    tree_view = gtk_tree_view_column_get_tree_view (column);
    selection = gtk_tree_view_get_selection (GTK_TREE_VIEW (tree_view));
    is_selected = gtk_tree_selection_iter_is_selected (selection, iter);

    gtk_tree_view_get_drag_dest_row (
        GTK_TREE_VIEW (tree_view), &drag_dest_row, NULL);
    if (drag_dest_row != NULL) {
        GtkTreePath *path;

        path = gtk_tree_model_get_path (model, iter);
        if (gtk_tree_path_compare (path, drag_dest_row) == 0)
            is_drag_dest = TRUE;
        gtk_tree_path_free (path);

        gtk_tree_path_free (drag_dest_row);
    }

    if (g_strcmp0 (icon_name, "folder") == 0) {
        if (is_selected) {
            g_free (icon_name);
            icon_name = g_strdup ("folder-open");
        } else if (is_drag_dest) {
            g_free (icon_name);
            icon_name = g_strdup ("folder-drag-accept");
        }
    }

    icon = g_themed_icon_new (icon_name);

    /* Show an emblem if there's new mail. */
    if (!is_selected && unread > old_unread && !is_drafts) {
        GIcon *temp_icon;
        GEmblem *emblem;

        temp_icon = g_themed_icon_new ("emblem-new");
        emblem = g_emblem_new (temp_icon);
        g_object_unref (temp_icon);

        temp_icon = g_emblemed_icon_new (icon, emblem);
        g_object_unref (emblem);
        g_object_unref (icon);

        icon = temp_icon;
    }

    g_object_set (renderer, "gicon", icon, NULL);

    g_object_unref (icon);
    g_free (icon_name);
}

static GtkTreeView *
folder_tree_new (EMFolderTree *folder_tree)
{
    GtkTreeSelection *selection;
    GtkTreeViewColumn *column;
    GtkCellRenderer *renderer;
    GtkWidget *tree;

    /* FIXME Gross hack */
    tree = GTK_WIDGET (folder_tree);
    gtk_widget_set_can_focus (tree, TRUE);

    folder_tree->priv->selectable = NULL;

    column = gtk_tree_view_column_new ();
    gtk_tree_view_append_column ((GtkTreeView *) tree, column);

    renderer = gtk_cell_renderer_pixbuf_new ();
    gtk_tree_view_column_pack_start (column, renderer, FALSE);
    gtk_tree_view_column_add_attribute (
        column, renderer, "visible", COL_BOOL_IS_FOLDER);
    gtk_tree_view_column_set_cell_data_func (
        column, renderer, (GtkTreeCellDataFunc)
        render_icon, NULL, NULL);

    renderer = gtk_cell_renderer_text_new ();
    gtk_tree_view_column_pack_start (column, renderer, TRUE);
    gtk_tree_view_column_set_cell_data_func (
        column, renderer, render_display_name, NULL, NULL);
    folder_tree->priv->text_renderer = g_object_ref (renderer);

    g_object_bind_property (
        folder_tree, "ellipsize",
        renderer, "ellipsize",
        G_BINDING_SYNC_CREATE);

    g_signal_connect_swapped (
        renderer, "edited",
        G_CALLBACK (folder_tree_cell_edited_cb), folder_tree);

    selection = gtk_tree_view_get_selection ((GtkTreeView *) tree);
    gtk_tree_selection_set_mode (selection, GTK_SELECTION_SINGLE);
    gtk_tree_selection_set_select_function (
        selection, (GtkTreeSelectionFunc)
        folder_tree_select_func, NULL, NULL);
    gtk_tree_view_set_headers_visible ((GtkTreeView *) tree, FALSE);

    gtk_tree_view_set_search_column ((GtkTreeView *) tree, COL_STRING_DISPLAY_NAME);

    return (GtkTreeView *) tree;
}

static void
folder_tree_copy_expanded_cb (GtkTreeView *unused,
                              GtkTreePath *path,
                              GtkTreeView *tree_view)
{
    gtk_tree_view_expand_row (tree_view, path, FALSE);
}

static void
folder_tree_copy_selection_cb (GtkTreeModel *model,
                               GtkTreePath *path,
                               GtkTreeIter *iter,
                               GtkTreeView *tree_view)
{
    GtkTreeSelection *selection;

    selection = gtk_tree_view_get_selection (tree_view);
    gtk_tree_selection_select_path (selection, path);

    /* Center the tree view on the selected path. */
    gtk_tree_view_scroll_to_cell (tree_view, path, NULL, TRUE, 0.5, 0.0);
}

static void
folder_tree_copy_state (EMFolderTree *folder_tree)
{
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;
    GtkTreeModel *model;

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = gtk_tree_view_get_model (tree_view);

    selection = em_folder_tree_model_get_selection (
        EM_FOLDER_TREE_MODEL (model));
    if (selection == NULL)
        return;

    gtk_tree_view_map_expanded_rows (
        tree_view, (GtkTreeViewMappingFunc)
        folder_tree_copy_expanded_cb, folder_tree);

    gtk_tree_selection_selected_foreach (
        selection, (GtkTreeSelectionForeachFunc)
        folder_tree_copy_selection_cb, folder_tree);
}

static void
em_folder_tree_construct (EMFolderTree *folder_tree)
{
    folder_tree_new (folder_tree);
    folder_tree_copy_state (folder_tree);
    gtk_widget_show (GTK_WIDGET (folder_tree));
}

static void
folder_tree_init (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GHashTable *select_uris_table;
    EMFolderTreeModel *model;
    gulong handler_id;
    AtkObject *a11y;

    select_uris_table = g_hash_table_new (g_str_hash, g_str_equal);

    folder_tree->priv = G_TYPE_INSTANCE_GET_PRIVATE (
        folder_tree, EM_TYPE_FOLDER_TREE, EMFolderTreePrivate);
    folder_tree->priv->select_uris_table = select_uris_table;

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = em_folder_tree_model_get_default ();
    selection = gtk_tree_view_get_selection (tree_view);

    gtk_tree_view_set_model (tree_view, GTK_TREE_MODEL (model));

    handler_id = g_signal_connect (
        model, "loading-row",
        G_CALLBACK (folder_tree_maybe_expand_row), folder_tree);
    folder_tree->priv->loading_row_id = handler_id;

    handler_id = g_signal_connect (
        model, "loaded-row",
        G_CALLBACK (folder_tree_maybe_expand_row), folder_tree);
    folder_tree->priv->loaded_row_id = handler_id;

    handler_id = g_signal_connect_swapped (
        selection, "changed",
        G_CALLBACK (folder_tree_selection_changed_cb), folder_tree);
    folder_tree->priv->selection_changed_handler_id = handler_id;

    a11y = gtk_widget_get_accessible (GTK_WIDGET (folder_tree));
    atk_object_set_name (a11y, _("Mail Folder Tree"));

    /* FIXME Kill this thing. */
    em_folder_tree_construct (folder_tree);
}

/* Sets a selectable widget, which will be used for update-actions and
 * select-all selectable interface functions. This can be NULL, then nothing
 * can be selected and calling selectable function does nothing. */
void
em_folder_tree_set_selectable_widget (EMFolderTree *folder_tree,
                                      GtkWidget *selectable)
{
    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    if (selectable != NULL)
        g_return_if_fail (E_IS_SELECTABLE (selectable));

    folder_tree->priv->selectable = selectable;
}

static void
folder_tree_selectable_update_actions (ESelectable *selectable,
                                        EFocusTracker *focus_tracker,
                                        GdkAtom *clipboard_targets,
                                        gint n_clipboard_targets)
{
    EMFolderTree *folder_tree;

    folder_tree = EM_FOLDER_TREE (selectable);
    g_return_if_fail (folder_tree != NULL);

    if (folder_tree->priv->selectable != NULL) {
        ESelectableInterface *interface;
        ESelectable *selectable;

        selectable = E_SELECTABLE (folder_tree->priv->selectable);
        interface = E_SELECTABLE_GET_INTERFACE (selectable);
        g_return_if_fail (interface->update_actions != NULL);

        interface->update_actions (
            selectable, focus_tracker,
            clipboard_targets, n_clipboard_targets);
    }
}

static void
folder_tree_selectable_cut_clipboard (ESelectable *selectable)
{
    ESelectableInterface *interface;
    EMFolderTree *folder_tree;
    GtkWidget *proxy;

    folder_tree = EM_FOLDER_TREE (selectable);
    proxy = folder_tree->priv->selectable;

    if (!E_IS_SELECTABLE (proxy))
        return;

    interface = E_SELECTABLE_GET_INTERFACE (proxy);

    if (interface->cut_clipboard == NULL)
        return;

    if (gtk_widget_get_can_focus (proxy))
        gtk_widget_grab_focus (proxy);

    interface->cut_clipboard (E_SELECTABLE (proxy));
}

static void
folder_tree_selectable_copy_clipboard (ESelectable *selectable)
{
    ESelectableInterface *interface;
    EMFolderTree *folder_tree;
    GtkWidget *proxy;

    folder_tree = EM_FOLDER_TREE (selectable);
    proxy = folder_tree->priv->selectable;

    if (!E_IS_SELECTABLE (proxy))
        return;

    interface = E_SELECTABLE_GET_INTERFACE (proxy);

    if (interface->copy_clipboard == NULL)
        return;

    if (gtk_widget_get_can_focus (proxy))
        gtk_widget_grab_focus (proxy);

    interface->copy_clipboard (E_SELECTABLE (proxy));
}

static void
folder_tree_selectable_paste_clipboard (ESelectable *selectable)
{
    ESelectableInterface *interface;
    EMFolderTree *folder_tree;
    GtkWidget *proxy;

    folder_tree = EM_FOLDER_TREE (selectable);
    proxy = folder_tree->priv->selectable;

    if (!E_IS_SELECTABLE (proxy))
        return;

    interface = E_SELECTABLE_GET_INTERFACE (proxy);

    if (interface->paste_clipboard == NULL)
        return;

    if (gtk_widget_get_can_focus (proxy))
        gtk_widget_grab_focus (proxy);

    interface->paste_clipboard (E_SELECTABLE (proxy));
}

static void
folder_tree_selectable_delete_selection (ESelectable *selectable)
{
    ESelectableInterface *interface;
    EMFolderTree *folder_tree;
    GtkWidget *proxy;

    folder_tree = EM_FOLDER_TREE (selectable);
    proxy = folder_tree->priv->selectable;

    if (!E_IS_SELECTABLE (proxy))
        return;

    interface = E_SELECTABLE_GET_INTERFACE (proxy);

    if (interface->delete_selection == NULL)
        return;

    if (gtk_widget_get_can_focus (proxy))
        gtk_widget_grab_focus (proxy);

    interface->delete_selection (E_SELECTABLE (proxy));
}

static void
folder_tree_selectable_select_all (ESelectable *selectable)
{
    ESelectableInterface *interface;
    EMFolderTree *folder_tree;
    GtkWidget *proxy;

    folder_tree = EM_FOLDER_TREE (selectable);
    proxy = folder_tree->priv->selectable;

    if (!E_IS_SELECTABLE (proxy))
        return;

    interface = E_SELECTABLE_GET_INTERFACE (proxy);

    if (interface->select_all == NULL)
        return;

    if (gtk_widget_get_can_focus (proxy))
        gtk_widget_grab_focus (proxy);

    interface->select_all (E_SELECTABLE (proxy));
}

static void
folder_tree_selectable_init (ESelectableInterface *interface)
{
    interface->update_actions = folder_tree_selectable_update_actions;
    interface->cut_clipboard = folder_tree_selectable_cut_clipboard;
    interface->copy_clipboard = folder_tree_selectable_copy_clipboard;
    interface->paste_clipboard = folder_tree_selectable_paste_clipboard;
    interface->delete_selection = folder_tree_selectable_delete_selection;
    interface->select_all = folder_tree_selectable_select_all;
}

GType
em_folder_tree_get_type (void)
{
    static GType type = 0;

    if (G_UNLIKELY (type == 0)) {
        static const GTypeInfo type_info = {
            sizeof (EMFolderTreeClass),
            (GBaseInitFunc) NULL,
            (GBaseFinalizeFunc) NULL,
            (GClassInitFunc) folder_tree_class_init,
            (GClassFinalizeFunc) NULL,
            NULL,  /* class_data */
            sizeof (EMFolderTree),
            0,     /* n_preallocs */
            (GInstanceInitFunc) folder_tree_init,
            NULL   /* value_table */
        };

        static const GInterfaceInfo selectable_info = {
            (GInterfaceInitFunc) folder_tree_selectable_init,
            (GInterfaceFinalizeFunc) NULL,
            NULL   /* interface_data */
        };

        type = g_type_register_static (
            GTK_TYPE_TREE_VIEW, "EMFolderTree", &type_info, 0);

        g_type_add_interface_static (
            type, E_TYPE_SELECTABLE, &selectable_info);
    }

    return type;
}

GtkWidget *
em_folder_tree_new (EMailSession *session)
{
    const gchar *data_dir;
    EShell *default_shell;
    EShellBackend *mail_backend;

    g_return_val_if_fail (E_IS_MAIL_SESSION (session), NULL);

    default_shell = e_shell_get_default ();
    mail_backend = e_shell_get_backend_by_name (default_shell, "mail");
    data_dir = e_shell_backend_get_data_dir (mail_backend);

    e_mail_store_init (session, data_dir);

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

PangoEllipsizeMode
em_folder_tree_get_ellipsize (EMFolderTree *folder_tree)
{
    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), 0);

    return folder_tree->priv->ellipsize;
}

void
em_folder_tree_set_ellipsize (EMFolderTree *folder_tree,
                              PangoEllipsizeMode ellipsize)
{
    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    if (ellipsize == folder_tree->priv->ellipsize)
        return;

    folder_tree->priv->ellipsize = ellipsize;

    g_object_notify (G_OBJECT (folder_tree), "ellipsize");
}

EMailSession *
em_folder_tree_get_session (EMFolderTree *folder_tree)
{
    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), NULL);

    return folder_tree->priv->session;
}

static void
tree_drag_begin (GtkWidget *widget,
                 GdkDragContext *context,
                 EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;
    cairo_surface_t *s;
    GtkTreeModel *model;
    GtkTreePath *path;
    GtkTreeIter iter;

    tree_view = GTK_TREE_VIEW (widget);
    selection = gtk_tree_view_get_selection (tree_view);
    if (!gtk_tree_selection_get_selected (selection, &model, &iter))
        return;

    path = gtk_tree_model_get_path (model, &iter);
    priv->drag_row = gtk_tree_row_reference_new (model, path);

    s = gtk_tree_view_create_row_drag_icon (tree_view, path);
    gtk_drag_set_icon_surface (context, s);

    gtk_tree_path_free (path);
}

static void
tree_drag_data_delete (GtkWidget *widget,
                       GdkDragContext *context,
                       EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    gchar *full_name = NULL;
    GtkTreeModel *model;
    GtkTreePath *src_path;
    gboolean is_store;
    CamelStore *store;
    GtkTreeIter iter;

    if (!priv->drag_row)
        return;

    src_path = gtk_tree_row_reference_get_path (priv->drag_row);
    if (src_path == NULL)
        return;

    model = gtk_tree_view_get_model (GTK_TREE_VIEW (folder_tree));

    if (!gtk_tree_model_get_iter (model, &iter, src_path))
        goto fail;

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_STRING_FULL_NAME, &full_name,
        COL_BOOL_IS_STORE, &is_store, -1);

    if (is_store)
        goto fail;

    /* FIXME camel_store_delete_folder_sync() may block. */
    camel_store_delete_folder_sync (store, full_name, NULL, NULL);

fail:
    gtk_tree_path_free (src_path);
    g_free (full_name);
}

static void
tree_drag_data_get (GtkWidget *widget,
                    GdkDragContext *context,
                    GtkSelectionData *selection,
                    guint info,
                    guint time,
                    EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    gchar *full_name = NULL, *uri = NULL;
    GtkTreeModel *model;
    GtkTreePath *src_path;
    CamelFolder *folder;
    CamelStore *store;
    GtkTreeIter iter;

    if (!priv->drag_row || !(src_path =
        gtk_tree_row_reference_get_path (priv->drag_row)))
        return;

    model = gtk_tree_view_get_model (GTK_TREE_VIEW (folder_tree));

    if (!gtk_tree_model_get_iter (model, &iter, src_path))
        goto fail;

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_STRING_FULL_NAME, &full_name,
        COL_STRING_URI, &uri, -1);

    /* make sure user isn't trying to drag on a placeholder row */
    if (full_name == NULL)
        goto fail;

    switch (info) {
    case DND_DRAG_TYPE_FOLDER:
        /* dragging to a new location in the folder tree */
        gtk_selection_data_set (
            selection, drag_atoms[info], 8,
            (guchar *) uri, strlen (uri) + 1);
        break;
    case DND_DRAG_TYPE_TEXT_URI_LIST:
        /* dragging to nautilus or something, probably */
        /* FIXME camel_store_get_folder_sync() may block. */
        if ((folder = camel_store_get_folder_sync (
            store, full_name, 0, NULL, NULL))) {

            GPtrArray *uids = camel_folder_get_uids (folder);

            em_utils_selection_set_urilist (selection, folder, uids);
            camel_folder_free_uids (folder, uids);
            g_object_unref (folder);
        }
        break;
    default:
        abort ();
    }

fail:
    gtk_tree_path_free (src_path);
    g_free (full_name);
    g_free (uri);
}

/* Drop handling */
struct _DragDataReceivedAsync {
    MailMsg base;

    /* input data */
    GdkDragContext *context;

    /* Only selection->data and selection->length are valid */
    GtkSelectionData *selection;

    EMailSession *session;
    CamelStore *store;
    gchar *full_name;
    guint32 action;
    guint info;

    guint move:1;
    guint moved:1;
    guint aborted:1;
};

static void
folder_tree_drop_folder (struct _DragDataReceivedAsync *m)
{
    CamelFolder *folder;
    CamelStore *parent_store;
    GCancellable *cancellable;
    const gchar *full_name;
    const guchar *data;

    data = gtk_selection_data_get_data (m->selection);

    d(printf(" * Drop folder '%s' onto '%s'\n", data, m->full_name));

    cancellable = e_activity_get_cancellable (m->base.activity);

    folder = e_mail_session_uri_to_folder_sync (
        m->session, (gchar *) data, 0,
        cancellable, &m->base.error);
    if (folder == NULL)
        return;

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

    em_folder_utils_copy_folders (
        parent_store, full_name, m->store,
        m->full_name ? m->full_name : "", m->move);

    g_object_unref (folder);
}

static gchar *
folder_tree_drop_async__desc (struct _DragDataReceivedAsync *m)
{
    CamelURL *url;
    const guchar *data;
    gchar *buf;

    data = gtk_selection_data_get_data (m->selection);

    if (m->info == DND_DROP_TYPE_FOLDER) {
        url = camel_url_new ((gchar *) data, NULL);

        if (m->move)
            buf = g_strdup_printf (
                _("Moving folder %s"), url->fragment ?
                url->fragment : url->path + 1);
        else
            buf = g_strdup_printf (
                _("Copying folder %s"), url->fragment ?
                url->fragment : url->path + 1);

        camel_url_free (url);

        return buf;
    } else {
        if (m->move)
            return g_strdup_printf (
                _("Moving messages into folder %s"),
                m->full_name);
        else
            return g_strdup_printf (
                _("Copying messages into folder %s"),
                m->full_name);
    }
}

static void
folder_tree_drop_async__exec (struct _DragDataReceivedAsync *m,
                              GCancellable *cancellable,
                              GError **error)
{
    CamelFolder *folder;

    /* for types other than folder, we can't drop to the root path */
    if (m->info == DND_DROP_TYPE_FOLDER) {
        /* copy or move (aka rename) a folder */
        folder_tree_drop_folder (m);
    } else if (m->full_name == NULL) {
        g_set_error (
            error, CAMEL_ERROR, CAMEL_ERROR_GENERIC,
            _("Cannot drop message(s) into toplevel store"));
    } else if ((folder = camel_store_get_folder_sync (
        m->store, m->full_name, 0, cancellable, error))) {

        switch (m->info) {
        case DND_DROP_TYPE_UID_LIST:
            /* import a list of uids from another evo folder */
            em_utils_selection_get_uidlist (
                m->selection, m->session, folder, m->move,
                cancellable, error);
            m->moved = m->move && (!error || !*error);
            break;
        case DND_DROP_TYPE_MESSAGE_RFC822:
            /* import a message/rfc822 stream */
            em_utils_selection_get_message (m->selection, folder);
            break;
        case DND_DROP_TYPE_TEXT_URI_LIST:
            /* import an mbox, maildir, or mh folder? */
            em_utils_selection_get_urilist (m->selection, folder);
            break;
        default:
            abort ();
        }
        g_object_unref (folder);
    }
}

static void
folder_tree_drop_async__free (struct _DragDataReceivedAsync *m)
{
    g_object_unref (m->session);
    g_object_unref (m->context);
    g_object_unref (m->store);
    g_free (m->full_name);
    gtk_selection_data_free (m->selection);
}

static MailMsgInfo folder_tree_drop_async_info = {
    sizeof (struct _DragDataReceivedAsync),
    (MailMsgDescFunc) folder_tree_drop_async__desc,
    (MailMsgExecFunc) folder_tree_drop_async__exec,
    (MailMsgDoneFunc) NULL,
    (MailMsgFreeFunc) folder_tree_drop_async__free
};

static void
tree_drag_data_action (struct _DragDataReceivedAsync *m)
{
    m->move = m->action == GDK_ACTION_MOVE;
    mail_msg_unordered_push (m);
}

static void
tree_drag_data_received (GtkWidget *widget,
                         GdkDragContext *context,
                         gint x,
                         gint y,
                         GtkSelectionData *selection,
                         guint info,
                         guint time,
                         EMFolderTree *folder_tree)
{
    GtkTreeViewDropPosition pos;
    GtkTreeModel *model;
    GtkTreeView *tree_view;
    GtkTreePath *dest_path = NULL;
    EMailSession *session;
    struct _DragDataReceivedAsync *m;
    gboolean is_store;
    CamelStore *store;
    GtkTreeIter iter;
    gchar *full_name;

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = gtk_tree_view_get_model (tree_view);

    session = em_folder_tree_get_session (folder_tree);

    if (!gtk_tree_view_get_dest_row_at_pos (tree_view, x, y, &dest_path, &pos))
        return;

    /* this means we are receiving no data */
    if (gtk_selection_data_get_data (selection) == NULL) {
        gtk_drag_finish (context, FALSE, FALSE, GDK_CURRENT_TIME);
        gtk_tree_path_free (dest_path);
        return;
    }

    if (gtk_selection_data_get_length (selection) == -1) {
        gtk_drag_finish (context, FALSE, FALSE, GDK_CURRENT_TIME);
        gtk_tree_path_free (dest_path);
        return;
    }

    if (!gtk_tree_model_get_iter (model, &iter, dest_path)) {
        gtk_drag_finish (context, FALSE, FALSE, GDK_CURRENT_TIME);
        gtk_tree_path_free (dest_path);
        return;
    }

    gtk_tree_model_get (
        model, &iter,
        COL_POINTER_CAMEL_STORE, &store,
        COL_BOOL_IS_STORE, &is_store,
        COL_STRING_FULL_NAME, &full_name, -1);

    /* make sure user isn't try to drop on a placeholder row */
    if (full_name == NULL && !is_store) {
        gtk_drag_finish (context, FALSE, FALSE, GDK_CURRENT_TIME);
        gtk_tree_path_free (dest_path);
        return;
    }

    m = mail_msg_new (&folder_tree_drop_async_info);
    m->session = g_object_ref (session);
    m->context = g_object_ref (context);
    m->store = g_object_ref (store);
    m->full_name = full_name;
    m->action = gdk_drag_context_get_selected_action (context);
    m->info = info;

    /* need to copy, goes away once we exit */
    m->selection = gtk_selection_data_copy (selection);

    tree_drag_data_action (m);
    gtk_tree_path_free (dest_path);
}

static gboolean
is_special_local_folder (const gchar *name)
{
    return strcmp (name, "Drafts") == 0
        || strcmp (name, "Inbox") == 0
        || strcmp (name, "Outbox") == 0
        || strcmp (name, "Sent") == 0
        || strcmp (name, "Templates") == 0;
}

static GdkAtom
folder_tree_drop_target (EMFolderTree *folder_tree,
                         GdkDragContext *context,
                         GtkTreePath *path,
                         GdkDragAction *actions,
                         GdkDragAction *suggested_action)
{
    EMFolderTreePrivate *p = folder_tree->priv;
    gchar *full_name = NULL, *uri = NULL, *src_uri = NULL;
    CamelStore *local, *sstore, *dstore;
    GdkAtom atom = GDK_NONE;
    gboolean is_store;
    GtkTreeModel *model;
    GtkTreeIter iter;
    GList *targets;
    guint32 flags = 0;

    /* This is a bit of a mess, but should handle all the cases properly */

    model = gtk_tree_view_get_model (GTK_TREE_VIEW (folder_tree));

    if (!gtk_tree_model_get_iter (model, &iter, path))
        return GDK_NONE;

    /* We may override these further down. */
    *actions = gdk_drag_context_get_actions (context);
    *suggested_action = gdk_drag_context_get_suggested_action (context);

    gtk_tree_model_get (
        model, &iter,
        COL_BOOL_IS_STORE, &is_store,
        COL_STRING_FULL_NAME, &full_name,
        COL_UINT_FLAGS, &flags,
        COL_POINTER_CAMEL_STORE, &dstore,
        COL_STRING_URI, &uri, -1);

    local = e_mail_local_get_store ();

    targets = gdk_drag_context_list_targets (context);

    /* Check for special destinations */
    if (uri && full_name) {
        /* don't allow copying/moving into the UNMATCHED vfolder */
        if (!strncmp (uri, "vfolder:", 8) && !strcmp (full_name, CAMEL_UNMATCHED_NAME))
            goto done;

        /* don't allow copying/moving into a vTrash/vJunk folder */
        if (!strcmp (full_name, CAMEL_VTRASH_NAME)
            || !strcmp (full_name, CAMEL_VJUNK_NAME))
            goto done;

        if (flags & CAMEL_FOLDER_NOSELECT)
            goto done;
    }

    if (p->drag_row) {
        GtkTreePath *src_path = gtk_tree_row_reference_get_path (p->drag_row);

        if (src_path) {
            guint32 src_flags = 0;

            if (gtk_tree_model_get_iter (model, &iter, src_path))
                gtk_tree_model_get (
                    model, &iter,
                    COL_POINTER_CAMEL_STORE, &sstore,
                    COL_STRING_URI, &src_uri,
                    COL_UINT_FLAGS, &src_flags, -1);

            /* can't dnd onto itself or below itself - bad things happen,
               no point dragging to where we were either */
            if (gtk_tree_path_compare (path, src_path) == 0
                || gtk_tree_path_is_descendant (path, src_path)
                || (gtk_tree_path_is_ancestor (path, src_path)
                && gtk_tree_path_get_depth (path) ==
                   gtk_tree_path_get_depth (src_path) - 1)) {
                gtk_tree_path_free (src_path);
                goto done;
            }

            gtk_tree_path_free (src_path);

            if ((src_flags & CAMEL_FOLDER_TYPE_MASK) == CAMEL_FOLDER_TYPE_INBOX ||
                (src_flags & CAMEL_FOLDER_SYSTEM) != 0) {
                /* allow only copy of the Inbox and other system folders */
                GdkAtom xfolder;

                /* force copy for special local folders */
                *suggested_action = GDK_ACTION_COPY;
                *actions = GDK_ACTION_COPY;
                xfolder = drop_atoms[DND_DROP_TYPE_FOLDER];
                while (targets != NULL) {
                    if (targets->data == (gpointer) xfolder) {
                        atom = xfolder;
                        goto done;
                    }

                    targets = targets->next;
                }

                goto done;
            }
        }
    }

    /* Check for special sources, and vfolder stuff */
    if (src_uri) {
        CamelURL *url;
        gchar *url_path;

        /* FIXME: this is a total hack, but i think all we can do at present */
        /* Check for dragging from special folders which can't be moved/copied */
        url = camel_url_new (src_uri, NULL);
        url_path = url->fragment?url->fragment:url->path;
        if (url_path && url_path[0]) {
            /* don't allow moving any of the the local special folders */
            if (sstore == local && is_special_local_folder (url_path)) {
                GdkAtom xfolder;

                camel_url_free (url);

                /* force copy for special local folders */
                *suggested_action = GDK_ACTION_COPY;
                *actions = GDK_ACTION_COPY;
                xfolder = drop_atoms[DND_DROP_TYPE_FOLDER];
                while (targets != NULL) {
                    if (targets->data == (gpointer) xfolder) {
                        atom = xfolder;
                        goto done;
                    }

                    targets = targets->next;
                }

                goto done;
            }

            /* Don't allow copying/moving the UNMATCHED vfolder. */
            if (!strcmp (url->protocol, "vfolder") &&
                !strcmp (url_path, CAMEL_UNMATCHED_NAME)) {
                camel_url_free (url);
                goto done;
            }

            /* Don't allow copying/moving any vTrash/vJunk
             * folder nor maildir 'inbox'. */
            if (strcmp (url_path, CAMEL_VTRASH_NAME) == 0
                || strcmp (url_path, CAMEL_VJUNK_NAME) == 0
                /* Dont allow drag from maildir 'inbox' */
                || strcmp(url_path, ".") == 0) {
                camel_url_free (url);
                goto done;
            }
        }
        camel_url_free (url);

        /* Search Folders can only be dropped into other Search Folders */
        if (strncmp(src_uri, "vfolder:", 8) == 0) {
            /* force move only for vfolders */
            *suggested_action = GDK_ACTION_MOVE;

            if (uri && strncmp(uri, "vfolder:", 8) == 0) {
                GdkAtom xfolder;

                xfolder = drop_atoms[DND_DROP_TYPE_FOLDER];
                while (targets != NULL) {
                    if (targets->data == (gpointer) xfolder) {
                        atom = xfolder;
                        goto done;
                    }

                    targets = targets->next;
                }
            }

            goto done;
        }
    }

    /* can't drag anything but a vfolder into a vfolder */
    if (uri && strncmp(uri, "vfolder:", 8) == 0)
        goto done;

    /* Now we either have a store or a normal folder */

    if (is_store) {
        GdkAtom xfolder;

        xfolder = drop_atoms[DND_DROP_TYPE_FOLDER];
        while (targets != NULL) {
            if (targets->data == (gpointer) xfolder) {
                atom = xfolder;
                goto done;
            }

            targets = targets->next;
        }
    } else {
        gint i;

        while (targets != NULL) {
            for (i = 0; i < NUM_DROP_TYPES; i++) {
                if (targets->data == (gpointer) drop_atoms[i]) {
                    atom = drop_atoms[i];
                    goto done;
                }
            }

            targets = targets->next;
        }
    }

 done:

    g_free (full_name);
    g_free (uri);

    return atom;
}

static gboolean
tree_drag_drop (GtkWidget *widget,
                GdkDragContext *context,
                gint x,
                gint y,
                guint time,
                EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeViewColumn *column;
    GtkTreeView *tree_view;
    gint cell_x, cell_y;
    GdkDragAction actions;
    GdkDragAction suggested_action;
    GtkTreePath *path;
    GdkAtom target;

    tree_view = GTK_TREE_VIEW (folder_tree);

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

    if (priv->autoexpand_id != 0) {
        gtk_tree_row_reference_free (priv->autoexpand_row);
        priv->autoexpand_row = NULL;

        g_source_remove (priv->autoexpand_id);
        priv->autoexpand_id = 0;
    }

    if (!gtk_tree_view_get_path_at_pos (
        tree_view, x, y, &path, &column, &cell_x, &cell_y))
        return FALSE;

    target = folder_tree_drop_target (
        folder_tree, context, path,
        &actions, &suggested_action);

    gtk_tree_path_free (path);

    return (target != GDK_NONE);
}

static void
tree_drag_end (GtkWidget *widget,
               GdkDragContext *context,
               EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;

    if (priv->drag_row != NULL) {
        gtk_tree_row_reference_free (priv->drag_row);
        priv->drag_row = NULL;
    }

    /* FIXME: undo anything done in drag-begin */
}

static void
tree_drag_leave (GtkWidget *widget,
                 GdkDragContext *context,
                 guint time,
                 EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeView *tree_view;

    tree_view = GTK_TREE_VIEW (folder_tree);

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

    if (priv->autoexpand_id != 0) {
        gtk_tree_row_reference_free (priv->autoexpand_row);
        priv->autoexpand_row = NULL;

        g_source_remove (priv->autoexpand_id);
        priv->autoexpand_id = 0;
    }

    gtk_tree_view_set_drag_dest_row (
        tree_view, NULL, GTK_TREE_VIEW_DROP_BEFORE);
}

#define SCROLL_EDGE_SIZE 15

static gboolean
tree_autoscroll (EMFolderTree *folder_tree)
{
    GtkAdjustment *adjustment;
    GtkTreeView *tree_view;
    GdkRectangle rect;
    GdkWindow *window;
    gdouble value;
    gint offset, y;

    /* Get the y pointer position relative to the treeview. */
    tree_view = GTK_TREE_VIEW (folder_tree);
    window = gtk_tree_view_get_bin_window (tree_view);
    gdk_window_get_pointer (window, NULL, &y, NULL);

    /* Rect is in coorinates relative to the scrolled window,
     * relative to the treeview. */
    gtk_tree_view_get_visible_rect (tree_view, &rect);

    /* Move y into the same coordinate system as rect. */
    y += rect.y;

    /* See if we are near the top edge. */
    offset = y - (rect.y + 2 * SCROLL_EDGE_SIZE);
    if (offset > 0) {
        /* See if we are near the bottom edge. */
        offset = y - (rect.y + rect.height - 2 * SCROLL_EDGE_SIZE);
        if (offset < 0)
            return TRUE;
    }

    adjustment = gtk_tree_view_get_vadjustment (tree_view);
    value = gtk_adjustment_get_value (adjustment);
    gtk_adjustment_set_value (adjustment, MAX (value + offset, 0.0));

    return TRUE;
}

static gboolean
tree_autoexpand (EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeView *tree_view;
    GtkTreePath *path;

    tree_view = GTK_TREE_VIEW (folder_tree);
    path = gtk_tree_row_reference_get_path (priv->autoexpand_row);
    gtk_tree_view_expand_row (tree_view, path, FALSE);
    gtk_tree_path_free (path);

    return TRUE;
}

static gboolean
tree_drag_motion (GtkWidget *widget,
                  GdkDragContext *context,
                  gint x,
                  gint y,
                  guint time,
                  EMFolderTree *folder_tree)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    GtkTreeViewDropPosition pos;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GdkDragAction actions;
    GdkDragAction suggested_action;
    GdkDragAction chosen_action = 0;
    GtkTreePath *path = NULL;
    GtkTreeIter iter;
    GdkAtom target;
    gint i;

    tree_view = GTK_TREE_VIEW (folder_tree);
    model = gtk_tree_view_get_model (tree_view);

    if (!gtk_tree_view_get_dest_row_at_pos (tree_view, x, y, &path, &pos))
        return FALSE;

    if (priv->autoscroll_id == 0)
        priv->autoscroll_id = g_timeout_add (
            150, (GSourceFunc) tree_autoscroll, folder_tree);

    gtk_tree_model_get_iter (model, &iter, path);

    if (gtk_tree_model_iter_has_child (model, &iter) &&
        !gtk_tree_view_row_expanded (tree_view, path)) {

        if (priv->autoexpand_id != 0) {
            GtkTreePath *autoexpand_path;

            autoexpand_path = gtk_tree_row_reference_get_path (priv->autoexpand_row);
            if (gtk_tree_path_compare (autoexpand_path, path) != 0) {
                /* row changed, restart timer */
                gtk_tree_row_reference_free (priv->autoexpand_row);
                priv->autoexpand_row = gtk_tree_row_reference_new (model, path);
                g_source_remove (priv->autoexpand_id);
                priv->autoexpand_id = g_timeout_add (
                    600, (GSourceFunc)
                    tree_autoexpand, folder_tree);
            }

            gtk_tree_path_free (autoexpand_path);
        } else {
            priv->autoexpand_id = g_timeout_add (
                600, (GSourceFunc)
                tree_autoexpand, folder_tree);
            priv->autoexpand_row = gtk_tree_row_reference_new (model, path);
        }
    } else if (priv->autoexpand_id != 0) {
        gtk_tree_row_reference_free (priv->autoexpand_row);
        priv->autoexpand_row = NULL;

        g_source_remove (priv->autoexpand_id);
        priv->autoexpand_id = 0;
    }

    target = folder_tree_drop_target (
        folder_tree, context, path,
        &actions, &suggested_action);
    for (i = 0; target != GDK_NONE && i < NUM_DROP_TYPES; i++) {
        if (drop_atoms[i] != target)
            continue;
        switch (i) {
            case DND_DROP_TYPE_UID_LIST:
            case DND_DROP_TYPE_FOLDER:
                chosen_action = suggested_action;
                if (chosen_action == GDK_ACTION_COPY && (actions & GDK_ACTION_MOVE))
                    chosen_action = GDK_ACTION_MOVE;
                gtk_tree_view_set_drag_dest_row (
                    tree_view, path,
                    GTK_TREE_VIEW_DROP_INTO_OR_AFTER);
                break;
            default:
                gtk_tree_view_set_drag_dest_row (
                    tree_view, path,
                    GTK_TREE_VIEW_DROP_INTO_OR_AFTER);
                chosen_action = suggested_action;
                break;
        }

        break;
    }

    gdk_drag_status (context, chosen_action, time);
    gtk_tree_path_free (path);

    return chosen_action != 0;
}

void
em_folder_tree_enable_drag_and_drop (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    static gint setup = 0;
    gint i;

    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    tree_view = GTK_TREE_VIEW (folder_tree);

    if (!setup) {
        for (i=0; i<NUM_DRAG_TYPES; i++)
            drag_atoms[i] = gdk_atom_intern (drag_types[i].target, FALSE);

        for (i=0; i<NUM_DROP_TYPES; i++)
            drop_atoms[i] = gdk_atom_intern (drop_types[i].target, FALSE);

        setup = 1;
    }

    gtk_drag_source_set (
        GTK_WIDGET (tree_view), GDK_BUTTON1_MASK,drag_types,
        NUM_DRAG_TYPES, GDK_ACTION_COPY | GDK_ACTION_MOVE);
    gtk_drag_dest_set (
        GTK_WIDGET (tree_view), GTK_DEST_DEFAULT_ALL, drop_types,
        NUM_DROP_TYPES, GDK_ACTION_COPY | GDK_ACTION_MOVE);

    g_signal_connect (
        tree_view, "drag-begin",
        G_CALLBACK (tree_drag_begin), folder_tree);
    g_signal_connect (
        tree_view, "drag-data-delete",
        G_CALLBACK (tree_drag_data_delete), folder_tree);
    g_signal_connect (
        tree_view, "drag-data-get",
        G_CALLBACK (tree_drag_data_get), folder_tree);
    g_signal_connect (
        tree_view, "drag-data-received",
        G_CALLBACK (tree_drag_data_received), folder_tree);
    g_signal_connect (
        tree_view, "drag-drop",
        G_CALLBACK (tree_drag_drop), folder_tree);
    g_signal_connect (
        tree_view, "drag-end",
        G_CALLBACK (tree_drag_end), folder_tree);
    g_signal_connect (
        tree_view, "drag-leave",
        G_CALLBACK (tree_drag_leave), folder_tree);
    g_signal_connect (
        tree_view, "drag-motion",
        G_CALLBACK (tree_drag_motion), folder_tree);
}

void
em_folder_tree_set_excluded (EMFolderTree *folder_tree, guint32 flags)
{
    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    folder_tree->priv->excluded = flags;
}

void
em_folder_tree_set_excluded_func (EMFolderTree *folder_tree,
                                  EMFTExcludeFunc exclude,
                                  gpointer data)
{
    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));
    g_return_if_fail (exclude != NULL);

    folder_tree->priv->excluded_func = exclude;
    folder_tree->priv->excluded_data = data;
}

GList *
em_folder_tree_get_selected_uris (EMFolderTree *folder_tree)
{
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GList *list = NULL, *rows, *l;
    GSList *sl;

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    /* at first, add lost uris */
    for (sl = folder_tree->priv->select_uris; sl; sl = g_slist_next (sl))
        list = g_list_append (list, g_strdup (((struct _selected_uri *) sl->data)->uri));

    rows = gtk_tree_selection_get_selected_rows (selection, &model);
    for (l=rows; l; l=g_list_next (l)) {
        GtkTreeIter iter;
        GtkTreePath *path = l->data;

        if (gtk_tree_model_get_iter (model, &iter, path)) {
            gchar *uri;

            gtk_tree_model_get (model, &iter, COL_STRING_URI, &uri, -1);
            list = g_list_prepend (list, uri);
        }
        gtk_tree_path_free (path);
    }
    g_list_free (rows);

    return g_list_reverse (list);
}

static void
get_selected_uris_path_iterate (GtkTreeModel *model,
                                GtkTreePath *treepath,
                                GtkTreeIter *iter,
                                gpointer data)
{
    GList **list = (GList **) data;
    gchar *full_name;

    gtk_tree_model_get (model, iter, COL_STRING_FULL_NAME, &full_name, -1);
    *list = g_list_append (*list, full_name);
}

GList *
em_folder_tree_get_selected_paths (EMFolderTree *folder_tree)
{
    GtkTreeSelection *selection;
    GtkTreeView *tree_view;
    GList *list = NULL;

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    gtk_tree_selection_selected_foreach (
        selection, get_selected_uris_path_iterate, &list);

    return list;
}

void
em_folder_tree_set_selected_list (EMFolderTree *folder_tree,
                                  GList *list,
                                  gboolean expand_only)
{
    EMFolderTreePrivate *priv = folder_tree->priv;
    EMailSession *session;

    session = em_folder_tree_get_session (folder_tree);

    /* FIXME: need to remove any currently selected stuff? */
    if (!expand_only)
        folder_tree_clear_selected_list (folder_tree);

    for (;list;list = list->next) {
        CamelStore *store;
        struct _selected_uri *u;
        const gchar *folder_uri;
        const gchar *uid;
        gchar *folder_name;
        gchar *expand_key;
        gchar *end;
        gboolean success;

        /* This makes sure all our parents up to the root are
         * expanded. */

        folder_uri = list->data;

        success = e_mail_folder_uri_parse (
            CAMEL_SESSION (session), folder_uri,
            &store, &folder_name, NULL);

        if (!success)
            continue;

        uid = camel_service_get_uid (CAMEL_SERVICE (store));
        expand_key = g_strdup_printf ("%s/%s", uid, folder_name);
        g_free (folder_name);

        u = g_malloc0 (sizeof (*u));
        u->uri = g_strdup (folder_uri);
        u->service = CAMEL_SERVICE (store);  /* takes ownership */
        u->key = g_strdup (expand_key);

        if (!expand_only) {
            g_hash_table_insert (
                priv->select_uris_table, u->key, u);
            priv->select_uris =
                g_slist_append (priv->select_uris, u);
        }

        end = strrchr (expand_key, '/');
        do {
            folder_tree_expand_node (expand_key, folder_tree);
            *end = 0;
            end = strrchr (expand_key, '/');
        } while (end);

        g_free (expand_key);
    }
}

#if 0
static void
dump_fi (CamelFolderInfo *fi, gint depth)
{
    gint i;

    while (fi != NULL) {
        for (i = 0; i < depth; i++)
            fputs ("  ", stdout);

        printf ("path='%s'; full_name='%s'\n", fi->path, fi->full_name);

        if (fi->child)
            dump_fi (fi->child, depth + 1);

        fi = fi->sibling;
    }
}
#endif

void
em_folder_tree_set_selected (EMFolderTree *folder_tree,
                             const gchar *uri,
                             gboolean expand_only)
{
    GList *l = NULL;

    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    if (uri && uri[0])
        l = g_list_append (l, (gpointer) uri);

    em_folder_tree_set_selected_list (folder_tree, l, expand_only);
    g_list_free (l);
}

void
em_folder_tree_select_next_path (EMFolderTree *folder_tree, gboolean skip_read_folders)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter iter, parent, child;
    GtkTreePath *current_path, *path = NULL;
    guint unread = 0;
    EMFolderTreePrivate *priv = folder_tree->priv;

    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);
    if (gtk_tree_selection_get_selected (selection, &model, &iter)) {

        current_path = gtk_tree_model_get_path (model, &iter);

        do {
        if (gtk_tree_model_iter_has_child (model, &iter)) {
            gtk_tree_model_iter_children (model, &child, &iter);
            path = gtk_tree_model_get_path (model, &child);
            iter = child;
        } else {
            while (1) {
                gboolean has_parent = gtk_tree_model_iter_parent (model, &parent, &iter);
                if (gtk_tree_model_iter_next (model, &iter)) {
                    path = gtk_tree_model_get_path (model, &iter);
                    break;
                } else {
                    if (has_parent) {
                        iter =  parent;
                    } else {
                        /* Reached end. Wrapup*/
                        gtk_tree_model_get_iter_first (model, &iter);
                        path = gtk_tree_model_get_path (model, &iter);
                        break;
                    }
                }
            }
        }
        gtk_tree_model_get (model, &iter, COL_UINT_UNREAD, &unread, -1);

        /* TODO : Flags here for better options */
        } while (skip_read_folders && unread <=0 &&
            gtk_tree_path_compare (current_path, path));
    }

    if (path) {
        if (!gtk_tree_view_row_expanded (tree_view, path))
            gtk_tree_view_expand_to_path (tree_view, path);

        gtk_tree_selection_select_path (selection, path);

        if (!priv->cursor_set) {
            gtk_tree_view_set_cursor (tree_view, path, NULL, FALSE);
            priv->cursor_set = TRUE;
        }
        gtk_tree_view_scroll_to_cell (tree_view, path, NULL, TRUE, 0.5f, 0.0f);
    }
    return;
}

static gboolean
folder_tree_descend (GtkTreeModel *model,
                     GtkTreeIter *iter,
                     GtkTreeIter *root)
{
    GtkTreeIter parent;
    gint n_children;

    /* Finds the rightmost descendant of the given root. */

    if (root == NULL) {
        n_children = gtk_tree_model_iter_n_children (model, NULL);

        /* This will invalidate the iterator and return FALSE. */
        if (n_children == 0)
            return gtk_tree_model_get_iter_first (model, iter);

        gtk_tree_model_iter_nth_child (
            model, &parent, NULL, n_children - 1);
    } else
        parent = *root;

    n_children = gtk_tree_model_iter_n_children (model, &parent);

    while (n_children > 0) {
        GtkTreeIter child;

        gtk_tree_model_iter_nth_child (
            model, &child, &parent, n_children - 1);

        parent = child;

        n_children = gtk_tree_model_iter_n_children (model, &parent);
    }

    *iter = parent;

    return TRUE;
}

void
em_folder_tree_select_prev_path (EMFolderTree *folder_tree,
                                 gboolean skip_read_folders)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreePath *path = NULL;
    GtkTreePath *sentinel;
    GtkTreeIter iter;
    guint unread = 0;
    EMFolderTreePrivate *priv = folder_tree->priv;

    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    /* Nothing selected means nothing to do. */
    if (!gtk_tree_selection_get_selected (selection, &model, &iter))
        return;

    /* This prevents us from looping over the model indefinitely,
     * looking for unread messages when there are none. */
    sentinel = gtk_tree_model_get_path (model, &iter);

    do {
        GtkTreeIter descendant;

        if (path != NULL)
            gtk_tree_path_free (path);

        path = gtk_tree_model_get_path (model, &iter);

        if (gtk_tree_path_prev (path)) {
            gtk_tree_model_get_iter (model, &iter, path);
            folder_tree_descend (model, &descendant, &iter);

            gtk_tree_path_free (path);
            path = gtk_tree_model_get_path (model, &descendant);

        } else if (gtk_tree_path_get_depth (path) > 1) {
            gtk_tree_path_up (path);

        } else {
            folder_tree_descend (model, &descendant, NULL);

            gtk_tree_path_free (path);
            path = gtk_tree_model_get_path (model, &descendant);
        }

        gtk_tree_model_get_iter (model, &iter, path);
        gtk_tree_model_get (model, &iter, COL_UINT_UNREAD, &unread, -1);

    } while (skip_read_folders && unread <= 0 &&
        gtk_tree_path_compare (path, sentinel) != 0);

    if (!gtk_tree_view_row_expanded (tree_view, path))
        gtk_tree_view_expand_to_path (tree_view, path);

    gtk_tree_selection_select_path (selection, path);

    if (!priv->cursor_set) {
        gtk_tree_view_set_cursor (tree_view, path, NULL, FALSE);
        priv->cursor_set = TRUE;
    }

    gtk_tree_view_scroll_to_cell (
        tree_view, path, NULL, TRUE, 0.5f, 0.0f);

    gtk_tree_path_free (sentinel);
    gtk_tree_path_free (path);
}

void
em_folder_tree_edit_selected (EMFolderTree *folder_tree)
{
    GtkTreeSelection *selection;
    GtkTreeViewColumn *column;
    GtkCellRenderer *renderer;
    GtkTreeView *tree_view;
    GtkTreeModel *model;
    GtkTreePath *path = NULL;
    GtkTreeIter iter;

    g_return_if_fail (EM_IS_FOLDER_TREE (folder_tree));

    tree_view = GTK_TREE_VIEW (folder_tree);
    column = gtk_tree_view_get_column (tree_view, 0);
    selection = gtk_tree_view_get_selection (tree_view);
    renderer = folder_tree->priv->text_renderer;

    if (gtk_tree_selection_get_selected (selection, &model, &iter))
        path = gtk_tree_model_get_path (model, &iter);

    if (path == NULL)
        return;

    /* Make the text cell renderer editable, but only temporarily.
     * We don't want editing to be activated by simply clicking on
     * the folder name.  Too easy for accidental edits to occur. */
    g_object_set (renderer, "editable", TRUE, NULL);
    gtk_tree_view_expand_to_path (tree_view, path);
    gtk_tree_view_set_cursor_on_cell (
        tree_view, path, column, renderer, TRUE);
    g_object_set (renderer, "editable", FALSE, NULL);

    gtk_tree_path_free (path);
}

gchar *
em_folder_tree_get_selected_uri (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter iter;
    gchar *uri = NULL;

    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), NULL);

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    if (!gtk_tree_selection_get_selected (selection, &model, &iter))
        return NULL;

    gtk_tree_model_get (model, &iter, COL_STRING_URI, &uri, -1);

    return uri;
}

gchar *
em_folder_tree_get_selected_path (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter iter;
    gchar *name = NULL;

    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), NULL);

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    if (!gtk_tree_selection_get_selected (selection, &model, &iter))
        return NULL;

    gtk_tree_model_get (model, &iter, COL_STRING_FULL_NAME, &name, -1);

    return name;
}

CamelFolder *
em_folder_tree_get_selected_folder (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter iter;
    gchar *full_name = NULL;
    CamelStore *store = NULL;
    CamelFolder *folder = NULL;

    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), NULL);

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    if (gtk_tree_selection_get_selected (selection, &model, &iter))
        gtk_tree_model_get (
            model, &iter,
            COL_POINTER_CAMEL_STORE, &store,
            COL_STRING_FULL_NAME, &full_name, -1);

    /* FIXME camel_store_get_folder_sync() may block. */
    if (store && full_name)
        folder = camel_store_get_folder_sync (
            store, full_name,
            CAMEL_STORE_FOLDER_INFO_FAST, NULL, NULL);

    g_free (full_name);

    return folder;
}

EAccount *
em_folder_tree_get_selected_account (EMFolderTree *folder_tree)
{
    GtkTreeView *tree_view;
    GtkTreeSelection *selection;
    GtkTreeModel *model;
    GtkTreeIter iter;
    CamelStore *store = NULL;
    const gchar *uid = NULL;

    g_return_val_if_fail (EM_IS_FOLDER_TREE (folder_tree), NULL);

    tree_view = GTK_TREE_VIEW (folder_tree);
    selection = gtk_tree_view_get_selection (tree_view);

    if (gtk_tree_selection_get_selected (selection, &model, &iter))
        gtk_tree_model_get (
            model, &iter,
            COL_POINTER_CAMEL_STORE, &store, -1);

    if (CAMEL_IS_STORE (store))
        uid = camel_service_get_uid (CAMEL_SERVICE (store));

    return (uid != NULL) ? e_get_account_by_uid (uid) : NULL;
}

void
em_folder_tree_set_skip_double_click (EMFolderTree *folder_tree, gboolean skip)
{
    folder_tree->priv->skip_double_click = skip;
}

/* stores come first, then by uri */
static gint
sort_by_store_and_uri (gconstpointer name1, gconstpointer name2)
{
    const gchar *n1 = name1, *n2 = name2;
    gboolean is_store1, is_store2;

    if (n1 == NULL || n2 == NULL) {
        if (n1 == n2)
            return 0;
        else
            return n1 ? -1 : 1;
    }

    is_store1 = g_str_has_prefix (n1, "Store ");
    is_store2 = g_str_has_prefix (n2, "Store ");

    if ((is_store1 || is_store2) && (!is_store1 || !is_store2)) {
        return is_store1 ? -1 : 1;
    }

    return strcmp (n1, n2);
}

/* restores state of a tree (collapsed/expanded) as stores in the given key_file */
void
em_folder_tree_restore_state (EMFolderTree *folder_tree,
                              GKeyFile *key_file)
{
    EShell *shell;
    GtkTreeModel *tree_model;
    GtkTreeView *tree_view;
    GtkTreeIter iter;
    gboolean valid;
    gchar **groups_arr;
    GSList *groups, *group;
    gint ii;

    /* Make sure we have a key file to restore state from. */
    if (key_file == NULL)
        return;

    /* XXX Pass this in. */
    shell = e_shell_get_default ();

    tree_view = GTK_TREE_VIEW (folder_tree);
    tree_model = gtk_tree_view_get_model (tree_view);

    /* Set the initial folder tree expanded state in two stages:
     *
     * 1) Iterate over the "Store" and "Folder" state file groups
     *    and apply the "Expanded" keys where possible.
     *
     * 2) Iterate over the top-level nodes in the folder tree
     *    (these are all stores) and expand those that have no
     *    corresponding "Expanded" key in the state file.  This
     *    ensures that new stores are expanded by default.
     */

    /* Stage 1 */

    /* Collapse all so we have a clean slate. */
    gtk_tree_view_collapse_all (tree_view);

    groups_arr = g_key_file_get_groups (key_file, NULL);
    groups = NULL;

    for (ii = 0; groups_arr[ii] != NULL; ii++) {
        groups = g_slist_prepend (groups, groups_arr[ii]);
    }

    groups = g_slist_sort (groups, sort_by_store_and_uri);

    for (group = groups; group != NULL; group = group->next) {
        GtkTreeRowReference *reference;
        GtkTreePath *path;
        GtkTreeIter iter;
        const gchar *group_name = group->data;
        const gchar *key = STATE_KEY_EXPANDED;
        const gchar *uri;
        gboolean expanded;

        if (g_str_has_prefix (group_name, "Store ")) {
            uri = group_name + 6;
            expanded = TRUE;
        } else if (g_str_has_prefix (group_name, "Folder ")) {
            uri = group_name + 7;
            expanded = FALSE;
        } else
            continue;

        if (g_key_file_has_key (key_file, group_name, key, NULL))
            expanded = g_key_file_get_boolean (
                key_file, group_name, key, NULL);

        if (!expanded)
            continue;

        reference = em_folder_tree_model_lookup_uri (
            EM_FOLDER_TREE_MODEL (tree_model), uri);
        if (reference == NULL)
            continue;

        path = gtk_tree_row_reference_get_path (reference);
        gtk_tree_model_get_iter (tree_model, &iter, path);
        gtk_tree_view_expand_row (tree_view, path, FALSE);
        gtk_tree_path_free (path);
    }

    g_slist_free (groups);
    g_strfreev (groups_arr);

    /* Stage 2 */

    valid = gtk_tree_model_get_iter_first (tree_model, &iter);

    while (valid) {
        const gchar *key = STATE_KEY_EXPANDED;
        gboolean expand_row;
        gchar *group_name;
        gchar *uri;

        gtk_tree_model_get (
            tree_model, &iter, COL_STRING_URI, &uri, -1);

        if (uri == NULL)
            goto next;

        group_name = g_strdup_printf ("Store %s", uri);

        /* Expand stores that have no "Expanded" key. */
        expand_row = !g_key_file_has_key (
            key_file, group_name, key, NULL);

        /* Do not expand local stores in Express mode. */
        if (e_shell_get_express_mode (shell)) {
            expand_row &= (strncmp (uri, "vfolder", 7) != 0);
            expand_row &= (strncmp (uri, "maildir", 7) != 0);
        }

        if (expand_row) {
            GtkTreePath *path;

            path = gtk_tree_model_get_path (tree_model, &iter);
            gtk_tree_view_expand_row (tree_view, path, FALSE);
            gtk_tree_path_free (path);
        }

        g_free (group_name);
        g_free (uri);

    next:
        valid = gtk_tree_model_iter_next (tree_model, &iter);
    }
}