path: root/shell/e-storage-set-view.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/* e-storage-set-view.c
 *
 * Copyright (C) 2000, 2001 Ximian, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Author: Ettore Perazzoli
 * Etree-ification: Chris Toshok
 */

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

#include "e-storage-set-view.h"

#include <glib.h>
#include <gnome.h>
#include <libgnome/gnome-defs.h>
#include <libgnome/gnome-util.h>
#include <gal/util/e-util.h>
#include <gal/e-table/e-tree-memory-callbacks.h>
#include <gal/e-table/e-cell-tree.h>
#include <gal/e-table/e-cell-text.h>

#include <libgnome/gnome-util.h>

#include "e-util/e-gtk-utils.h"

#include "e-shell-constants.h"
#include "e-local-storage.h"

/*#define DEBUG_XML*/

#define DRAG_RESISTANCE 3   /* FIXME hardcoded in ETable to this value as
                 * well, and there is no way for us to use the
                 * same value as it's not exported.  */


/* This is used on the source side to define the two basic types that we always
   export.  */
enum _DndTargetTypeIdx {
    EVOLUTION_PATH_TARGET_TYPE_IDX = 0,
    E_SHORTCUT_TARGET_TYPE_IDX = 1
};
typedef enum _DndTargetTypeIdx DndTargetTypeIdx;

#define EVOLUTION_PATH_TARGET_TYPE "_EVOLUTION_PRIVATE_PATH"
#define E_SHORTCUT_TARGET_TYPE     "E-SHORTCUT"


#define PARENT_TYPE E_TREE_TYPE
static ETreeClass *parent_class = NULL;

struct _EStorageSetViewPrivate {
    EStorageSet *storage_set;

    BonoboUIContainer *container;

    ETreeModel *etree_model;
    ETreePath root_node;

    GHashTable *path_to_etree_node;

    GHashTable *type_name_to_pixbuf;

    /* Path of the row selected by the latest "cursor_activated" signal.  */
    const char *selected_row_path;

    gboolean show_folders;

    /* The `Evolution::ShellComponentDnd::SourceFolder' interface for the
       folder we are dragging from, or CORBA_OBJECT_NIL if no dragging is
       happening.  */
    GNOME_Evolution_ShellComponentDnd_SourceFolder drag_corba_source_interface;

    /* Source context information.  NULL if no dragging is in progress.  */
    GNOME_Evolution_ShellComponentDnd_SourceFolder_Context *drag_corba_source_context;

    /* The data.  */
    GNOME_Evolution_ShellComponentDnd_Data *drag_corba_data;

    /* When dragging, the X/Y coordinates of the point we drag from, as
       well as the corresponding row/column numbers in the table.  */
    int drag_x, drag_y;
    int drag_column, drag_row;
    ETreePath drag_path;
};


enum {
    FOLDER_SELECTED,
    STORAGE_SELECTED,
    DND_ACTION,
    LAST_SIGNAL
};

static unsigned int signals[LAST_SIGNAL] = { 0 };


/* DND stuff.  */

enum _DndTargetType {
    DND_TARGET_TYPE_URI_LIST,
    DND_TARGET_TYPE_E_SHORTCUT
};
typedef enum _DndTargetType DndTargetType;

#define URI_LIST_TYPE   "text/uri-list"
#define E_SHORTCUT_TYPE "E-SHORTCUT"


/* Sorting callbacks.  */

static int
storage_sort_callback (ETreeMemory *etmm,
               ETreePath node1,
               ETreePath node2,
               void *closure)
{
    char *folder_path1;
    char *folder_path2;
    gboolean path1_local;
    gboolean path2_local;

    folder_path1 = e_tree_memory_node_get_data(etmm, node1);
    folder_path2 = e_tree_memory_node_get_data(etmm, node2);
    
    path1_local = ! strcmp (folder_path1, G_DIR_SEPARATOR_S E_LOCAL_STORAGE_NAME);
    path2_local = ! strcmp (folder_path2, G_DIR_SEPARATOR_S E_LOCAL_STORAGE_NAME);

    if (path1_local && path2_local)
        return 0;
    if (path1_local)
        return -1;
    if (path2_local)
        return 1;
    
    return strcasecmp (e_tree_model_value_at (E_TREE_MODEL (etmm), node1, 0),
               e_tree_model_value_at (E_TREE_MODEL (etmm), node2, 0));
}

static int
folder_sort_callback (ETreeMemory *etmm, ETreePath path1, ETreePath path2, gpointer closure)
{
    return g_strcasecmp (e_tree_model_value_at (E_TREE_MODEL (etmm), path1, 0),
                 e_tree_model_value_at (E_TREE_MODEL (etmm), path2, 0));
}



/* Helper functions.  */

static gboolean
add_node_to_hash (EStorageSetView *storage_set_view,
          const char *path,
          ETreePath node)
{
    EStorageSetViewPrivate *priv;
    char *hash_path;

    g_return_val_if_fail (g_path_is_absolute (path), FALSE);

    priv = storage_set_view->priv;

    if (g_hash_table_lookup (priv->path_to_etree_node, path) != NULL) {
        g_warning ("EStorageSetView: Node already existing while adding -- %s", path);
        return FALSE;
    }

    hash_path = g_strdup (path);

    g_hash_table_insert (priv->path_to_etree_node, hash_path, node);

    return TRUE;
}

static ETreePath
lookup_node_in_hash (EStorageSetView *storage_set_view,
             const char *path)
{
    EStorageSetViewPrivate *priv;
    ETreePath node;

    priv = storage_set_view->priv;

    node = g_hash_table_lookup (priv->path_to_etree_node, path);
    if (node == NULL)
        g_warning ("EStorageSetView: Node not found while updating -- %s", path);

    return node;
}

static ETreePath
remove_node_from_hash (EStorageSetView *storage_set_view,
               const char *path)
{
    EStorageSetViewPrivate *priv;
    ETreePath node;

    priv = storage_set_view->priv;

    node = g_hash_table_lookup (priv->path_to_etree_node, path);
    if (node == NULL) {
        g_warning ("EStorageSetView: Node not found while removing -- %s", path);
        return NULL;
    }

    g_hash_table_remove (priv->path_to_etree_node, path);

    return node;
}

static GdkPixbuf*
get_pixbuf_for_folder (EStorageSetView *storage_set_view,
               EFolder *folder)
{
    GdkPixbuf *scaled_pixbuf;
    const char *type_name;
    EStorageSetViewPrivate *priv;

    priv = storage_set_view->priv;
    
    type_name = e_folder_get_type_string (folder);

    scaled_pixbuf = g_hash_table_lookup (priv->type_name_to_pixbuf, type_name);

    if (scaled_pixbuf == NULL) {
        EFolderTypeRegistry *folder_type_registry;
        EStorageSet *storage_set;
        GdkPixbuf *icon_pixbuf;
        int icon_pixbuf_width, icon_pixbuf_height;

        storage_set = priv->storage_set;
        folder_type_registry = e_storage_set_get_folder_type_registry (storage_set);

        icon_pixbuf = e_folder_type_registry_get_icon_for_type (folder_type_registry,
                                    type_name, TRUE);

        if (icon_pixbuf == NULL)
            return NULL;

        icon_pixbuf_width = gdk_pixbuf_get_width (icon_pixbuf);
        icon_pixbuf_height = gdk_pixbuf_get_height (icon_pixbuf);

        if (icon_pixbuf_width == E_SHELL_MINI_ICON_SIZE && icon_pixbuf_height == E_SHELL_MINI_ICON_SIZE) {
            scaled_pixbuf = gdk_pixbuf_ref (icon_pixbuf);
        } else {
            scaled_pixbuf = gdk_pixbuf_new (gdk_pixbuf_get_colorspace (icon_pixbuf),
                            gdk_pixbuf_get_has_alpha (icon_pixbuf),
                            gdk_pixbuf_get_bits_per_sample (icon_pixbuf),
                            E_SHELL_MINI_ICON_SIZE, E_SHELL_MINI_ICON_SIZE);

            gdk_pixbuf_scale (icon_pixbuf, scaled_pixbuf,
                      0, 0, E_SHELL_MINI_ICON_SIZE, E_SHELL_MINI_ICON_SIZE,
                      0.0, 0.0,
                      (double) E_SHELL_MINI_ICON_SIZE / gdk_pixbuf_get_width (icon_pixbuf),
                      (double) E_SHELL_MINI_ICON_SIZE / gdk_pixbuf_get_height (icon_pixbuf),
                      GDK_INTERP_HYPER);
        }

        g_hash_table_insert (priv->type_name_to_pixbuf, g_strdup (type_name), scaled_pixbuf);
    }

    return scaled_pixbuf;
}

static EFolder *
get_folder_at_node (EStorageSetView *storage_set_view,
            ETreePath path)
{
    EStorageSetViewPrivate *priv;
    const char *folder_path;

    priv = storage_set_view->priv;

    if (path == NULL)
        return NULL;

    folder_path = e_tree_memory_node_get_data (E_TREE_MEMORY(priv->etree_model), path);
    g_assert (folder_path != NULL);

    return e_storage_set_get_folder (priv->storage_set, folder_path);
}

static EvolutionShellComponentClient *
get_component_at_node (EStorageSetView *storage_set_view,
               ETreePath path)
{
    EStorageSetViewPrivate *priv;
    EvolutionShellComponentClient *component_client;
    EFolderTypeRegistry *folder_type_registry;
    EFolder *folder;

    priv = storage_set_view->priv;

    folder = get_folder_at_node (storage_set_view, path);
    if (folder == NULL)
        return NULL;

    folder_type_registry = e_storage_set_get_folder_type_registry (priv->storage_set);
    g_assert (folder_type_registry != NULL);

    component_client = e_folder_type_registry_get_handler_for_type (folder_type_registry,
                                    e_folder_get_type_string (folder));

    return component_client;
}

static GNOME_Evolution_ShellComponentDnd_ActionSet
convert_gdk_drag_action_set_to_corba (GdkDragAction action)
{
    GNOME_Evolution_ShellComponentDnd_Action retval;

    retval = GNOME_Evolution_ShellComponentDnd_ACTION_DEFAULT;

    if (action & GDK_ACTION_COPY)
        retval |= GNOME_Evolution_ShellComponentDnd_ACTION_COPY;
    if (action & GDK_ACTION_MOVE)
        retval |= GNOME_Evolution_ShellComponentDnd_ACTION_MOVE;
    if (action & GDK_ACTION_LINK)
        retval |= GNOME_Evolution_ShellComponentDnd_ACTION_LINK;
    if (action & GDK_ACTION_ASK)
        retval |= GNOME_Evolution_ShellComponentDnd_ACTION_ASK;

    return retval;
}

#if 0
static GdkDragAction
convert_corba_drag_action_set_to_gdk (GNOME_Evolution_ShellComponentDnd_ActionSet action)
{
    GdkDragAction retval;

    retval = GDK_ACTION_DEFAULT;

    if (action & GNOME_Evolution_ShellComponentDnd_ACTION_COPY)
        retval |= GDK_ACTION_COPY;
    if (action & GNOME_Evolution_ShellComponentDnd_ACTION_MOVE)
        retval |= GDK_ACTION_MOVE;
    if (action & GNOME_Evolution_ShellComponentDnd_ACTION_LINK)
        retval |= GDK_ACTION_LINK;
    if (action & GNOME_Evolution_ShellComponentDnd_ACTION_ASK)
        retval |= GDK_ACTION_ASK;

    return retval;
}
#endif


static GNOME_Evolution_ShellComponentDnd_ActionSet
convert_gdk_drag_action_to_corba (GdkDragAction action)
{
    if (action == GDK_ACTION_COPY)
        return GNOME_Evolution_ShellComponentDnd_ACTION_COPY;
    else if (action == GDK_ACTION_MOVE)
        return GNOME_Evolution_ShellComponentDnd_ACTION_MOVE;
    else if (action == GDK_ACTION_LINK)
        return GNOME_Evolution_ShellComponentDnd_ACTION_LINK;
    else if (action == GDK_ACTION_ASK)
        return GNOME_Evolution_ShellComponentDnd_ACTION_ASK;
    else {
        g_warning ("Unknown GdkDragAction %d", action);
        return GNOME_Evolution_ShellComponentDnd_ACTION_DEFAULT;
    }
}

static GdkDragAction
convert_corba_drag_action_to_gdk (GNOME_Evolution_ShellComponentDnd_ActionSet action)
{
    if (action == GNOME_Evolution_ShellComponentDnd_ACTION_COPY)
        return GDK_ACTION_COPY;
    else if (action == GNOME_Evolution_ShellComponentDnd_ACTION_MOVE)
        return GDK_ACTION_MOVE;
    else if (action == GNOME_Evolution_ShellComponentDnd_ACTION_LINK)
        return GDK_ACTION_LINK;
    else if (action == GNOME_Evolution_ShellComponentDnd_ACTION_ASK)
        return GDK_ACTION_ASK;
    else {
        g_warning ("unknown GNOME_Evolution_ShellComponentDnd_ActionSet %d", action);
        return GDK_ACTION_DEFAULT;
    }
}

/* This will look for the targets in @drag_context, choose one that matches
   with the allowed types at @path, and return its name.  The EVOLUTION_PATH
   type always matches.  */
static const char *
find_matching_target_for_drag_context (EStorageSetView *storage_set_view,
                       ETreePath path,
                       GdkDragContext *drag_context)
{
    EStorageSetViewPrivate *priv;
    EFolderTypeRegistry *folder_type_registry;
    EFolder *folder;
    GList *accepted_types;
    GList *p, *q;

    priv = storage_set_view->priv;
    folder_type_registry = e_storage_set_get_folder_type_registry (priv->storage_set);

    folder = get_folder_at_node (storage_set_view, path);
    if (folder == NULL)
        return NULL;

    accepted_types = e_folder_type_registry_get_accepted_dnd_types_for_type (folder_type_registry,
                                         e_folder_get_type_string (folder));

    /* FIXME?  We might make this more efficient.  Currently it takes `n *
       m' string compares, where `n' is the number of targets in the
       @drag_context, and `m' is the number of supported types in
       @folder.  */

    for (p = drag_context->targets; p != NULL; p = p->next) {
        char *possible_type;

        possible_type = gdk_atom_name ((GdkAtom) p->data);
        if (strcmp (possible_type, EVOLUTION_PATH_TARGET_TYPE) == 0) {
            g_free (possible_type);
            return EVOLUTION_PATH_TARGET_TYPE;
        }

        for (q = accepted_types; q != NULL; q = q->next) {
            const char *accepted_type;

            accepted_type = (const char *) q->data;
            if (strcmp (possible_type, accepted_type) == 0) {
                g_free (possible_type);
                return accepted_type;
            }
        }

        g_free (possible_type);
    }

    return NULL;
}


/* Custom marshalling function.  */

typedef void (* GtkSignal_NONE__GDKDRAGCONTEXT_STRING_STRING_STRING) (GtkObject *object,
                                      GdkDragContext *action,
                                      const char *,
                                      const char *,
                                      const char *);

static void
marshal_NONE__GDKDRAGCONTEXT_STRING_STRING_STRING (GtkObject *object,
                           GtkSignalFunc func,
                           void *func_data,
                           GtkArg *args)
{
    GtkSignal_NONE__GDKDRAGCONTEXT_STRING_STRING_STRING rfunc;

    rfunc = (GtkSignal_NONE__GDKDRAGCONTEXT_STRING_STRING_STRING) func;
    (* rfunc) (object,
           GTK_VALUE_POINTER (args[0]),
           GTK_VALUE_STRING (args[1]),
           GTK_VALUE_STRING (args[2]),
           GTK_VALUE_STRING (args[3]));
}


/* DnD selection setup stuff.  */

/* This will create an array of GtkTargetEntries from the specified list of DND
   types.  The type name will *not* be allocated in the list, as this is
   supposed to be used only temporarily to set up the cell as a drag source.  */
static GtkTargetEntry *
create_target_entries_from_dnd_type_list (GList *dnd_types,
                      int *num_entries_return)
{
    GtkTargetEntry *entries;
    GList *p;
    int num_entries;
    int i;

    if (dnd_types == NULL)
        num_entries = 0;
    else
        num_entries = g_list_length (dnd_types);

    /* We always add two entries, one for an Evolution URI type, and one
       for e-shortcuts.  This will let us do drag & drop within Evolution
       at least.  */
    num_entries += 2;

    entries = g_new (GtkTargetEntry, num_entries);

    i = 0;

    /* The Evolution URI will always come first.  */
    entries[i].target = EVOLUTION_PATH_TARGET_TYPE;
    entries[i].flags = 0;
    entries[i].info = i;
    g_assert (i == EVOLUTION_PATH_TARGET_TYPE_IDX);
    i ++;

    /* ...Then the shortcut type.  */
    entries[i].target = E_SHORTCUT_TARGET_TYPE;
    entries[i].flags = 0;
    entries[i].info = i;
    g_assert (i == E_SHORTCUT_TARGET_TYPE_IDX);
    i ++;

    for (p = dnd_types; p != NULL; p = p->next, i++) {
        const char *dnd_type;

        g_assert (i < num_entries);

        dnd_type = (const char *) p->data;

        entries[i].target = (char *) dnd_type;
        entries[i].flags  = 0;
        entries[i].info   = i;
    }

    *num_entries_return = num_entries;
    return entries;
}

static void
free_target_entries (GtkTargetEntry *entries)
{
    g_assert (entries != NULL);

    /* The target names are not strdup()ed so a simple free will do.  */
    g_free (entries);
}

static GtkTargetList *
create_target_list_for_node (EStorageSetView *storage_set_view,
                 ETreePath node)
{
    EStorageSetViewPrivate *priv;
    GtkTargetList *target_list;
    EFolderTypeRegistry *folder_type_registry;
    GList *exported_dnd_types;
    GtkTargetEntry *target_entries;
    EFolder *folder;
    const char *folder_type;
    int num_target_entries;

    priv = storage_set_view->priv;

    folder_type_registry = e_storage_set_get_folder_type_registry (priv->storage_set);

    folder = get_folder_at_node (storage_set_view, node);
    folder_type = e_folder_get_type_string (folder);

    exported_dnd_types = e_folder_type_registry_get_exported_dnd_types_for_type (folder_type_registry,
                                             folder_type);

    target_entries = create_target_entries_from_dnd_type_list (exported_dnd_types,
                                   &num_target_entries);
    g_assert (target_entries != NULL);

    target_list = gtk_target_list_new (target_entries, num_target_entries);

    free_target_entries (target_entries);

    return target_list;
}

static void
set_e_shortcut_selection (EStorageSetView *storage_set_view,
              GtkSelectionData *selection_data)
{
    EStorageSetViewPrivate *priv;
    int shortcut_len;
    char *shortcut;
    const char *trailing_slash;
    const char *name;

    g_assert (storage_set_view != NULL);
    g_assert (selection_data != NULL);

    priv = storage_set_view->priv;

    trailing_slash = strrchr (priv->selected_row_path, '/');
    if (trailing_slash == NULL)
        name = NULL;
    else
        name = trailing_slash + 1;

    /* FIXME: Get `evolution:' from somewhere instead of hardcoding it here.  */

    if (name != NULL)
        shortcut_len = strlen (name);
    else
        shortcut_len = 0;
    
    shortcut_len ++;    /* Separating zero.  */

    shortcut_len += strlen ("evolution:");
    shortcut_len += strlen (priv->selected_row_path);
    shortcut_len ++;    /* Trailing zero.  */

    shortcut = g_malloc (shortcut_len);

    if (name == NULL)
        sprintf (shortcut, "%cevolution:%s", '\0', priv->selected_row_path);
    else
        sprintf (shortcut, "%s%cevolution:%s", name, '\0', priv->selected_row_path);

    gtk_selection_data_set (selection_data, selection_data->target,
                8, (guchar *) shortcut, shortcut_len);

    g_free (shortcut);
}

static void
set_evolution_path_selection (EStorageSetView *storage_set_view,
                  GtkSelectionData *selection_data)
{
    EStorageSetViewPrivate *priv;

    g_assert (storage_set_view != NULL);
    g_assert (selection_data != NULL);

    priv = storage_set_view->priv;

    gtk_selection_data_set (selection_data, selection_data->target,
                8, (guchar *) priv->selected_row_path, strlen (priv->selected_row_path) + 1);
}


/* Callbacks for folder operations.  */

static void
folder_xfer_callback (EStorageSet *storage_set,
              EStorageResult result,
              void *data)
{
    g_print ("Folder Xfer result -- %s\n", e_storage_result_to_string (result));
}


/* Folder context menu.  */
/* FIXME: This should be moved somewhere else, so that also the shortcut code
   can share it.  */

#if 0
static void
folder_context_menu_activate_cb (BonoboUIComponent *uih,
                 void *data,
                 const char *path)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;

    gtk_signal_emit (GTK_OBJECT (storage_set_view), signals[FOLDER_SELECTED],
             priv->selected_row_path);
}

static void
remove_cb(EStorageSet *storage_set, EStorageResult result, void *data)
{
    g_print ("remove_cb: %d\n", result);
}

static void
folder_context_menu_remove_cb (BonoboUIComponent *uih,
                   void *data,
                   const char *path)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;

    e_storage_set_async_remove_folder (priv->storage_set, priv->selected_row_path,
                       remove_cb, storage_set_view);
}
#endif

static void
popup_folder_menu (EStorageSetView *storage_set_view,
           GdkEventButton *event)
{
    EvolutionShellComponentClient *handler;
    EStorageSetViewPrivate *priv;
    EFolderTypeRegistry *folder_type_registry;
    EFolder *folder;
    GtkWidget *menu;

    priv = storage_set_view->priv;

    folder = e_storage_set_get_folder (priv->storage_set, priv->selected_row_path);
    if (folder == NULL) {
        /* Uh!?  */
        return;
    }

    folder_type_registry = e_storage_set_get_folder_type_registry (priv->storage_set);
    g_assert (folder_type_registry != NULL);

    handler = e_folder_type_registry_get_handler_for_type (folder_type_registry,
                                   e_folder_get_type_string (folder));
    if (handler == NULL)
        return;

    menu = gtk_menu_new ();
    bonobo_window_add_popup (bonobo_ui_container_get_win (priv->container),
                 GTK_MENU (menu), "/popups/FolderPopup");

    evolution_shell_component_client_populate_folder_context_menu (handler,
                                       priv->container,
                                       e_folder_get_physical_uri (folder),
                                       e_folder_get_type_string (folder));

    gtk_widget_show (GTK_WIDGET (menu));
    gtk_menu_popup (GTK_MENU (menu), NULL, NULL, NULL, NULL, 3, event->time);
}


/* GtkObject methods.  */

static void
pixbuf_free_func (gpointer key, gpointer value, gpointer user_data)
{
    g_free (key);
    gdk_pixbuf_unref ((GdkPixbuf*)value);
}

static void
destroy (GtkObject *object)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;

    storage_set_view = E_STORAGE_SET_VIEW (object);
    priv = storage_set_view->priv;

    /* need to destroy our tree */
    e_tree_memory_node_remove (E_TREE_MEMORY(priv->etree_model), priv->root_node);
    gtk_object_unref (GTK_OBJECT (priv->etree_model));

    /* the data in the hash table was all freed by freeing the tree */
    g_hash_table_destroy (priv->path_to_etree_node);

    /* now free up all the type_names and pixbufs stored in the
           hash table and destroy the hash table itself */
    g_hash_table_foreach (priv->type_name_to_pixbuf, pixbuf_free_func, NULL);
    g_hash_table_destroy (priv->type_name_to_pixbuf);

    gtk_object_unref (GTK_OBJECT (priv->storage_set));

    if (priv->drag_corba_source_interface != CORBA_OBJECT_NIL) {
        CORBA_Environment ev;

        CORBA_exception_init (&ev);

        g_assert (priv->drag_corba_source_context != NULL);

        GNOME_Evolution_ShellComponentDnd_SourceFolder_endDrag (priv->drag_corba_source_interface,
                                    priv->drag_corba_source_context,
                                    &ev);

        Bonobo_Unknown_unref (priv->drag_corba_source_interface, &ev);
        CORBA_Object_release (priv->drag_corba_source_interface, &ev);

        CORBA_exception_free (&ev);
    }

    if (priv->drag_corba_source_context != NULL)
        CORBA_free (priv->drag_corba_source_context);

    if (priv->drag_corba_data != NULL)
        CORBA_free (priv->drag_corba_data);

    g_free (priv);

    (* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}


/* GtkWidget methods.  */

static int
button_press_event (GtkWidget *widget,
            GdkEventButton *event)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETree *tree;
    int row, column;

    storage_set_view = E_STORAGE_SET_VIEW (widget);
    priv = storage_set_view->priv;

    tree = E_TREE (widget);

    /* FIXME correct? */
    if (GTK_WIDGET_CLASS (parent_class)->button_press_event != NULL)
        (* GTK_WIDGET_CLASS (parent_class)->button_press_event) (widget, event);

    if (event->button != 1)
        return FALSE;

    e_tree_get_cell_at (tree, event->x, event->y, &row, &column);

    priv->drag_x = event->x;
    priv->drag_y = event->y;
    priv->drag_column = column;
    priv->drag_path = e_tree_node_at_row(E_TREE(storage_set_view), row);
    priv->drag_row = row;

    /* FIXME correct? */
    return TRUE;
}

static int
motion_notify_event (GtkWidget *widget,
             GdkEventMotion *event)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETree *tree;
    GtkTargetList *target_list;
    GdkDragAction actions;
    GdkDragContext *context;

    storage_set_view = E_STORAGE_SET_VIEW (widget);
    priv = storage_set_view->priv;

    tree = E_TREE (widget);

    /* FIXME correct? */
    if (GTK_WIDGET_CLASS (parent_class)->motion_notify_event != NULL)
        (* GTK_WIDGET_CLASS (parent_class)->motion_notify_event) (widget, event);

    /* FIXME correct? */
    if (! (event->state & GDK_BUTTON1_MASK))
        return FALSE;

    if (ABS (priv->drag_x - event->x) < DRAG_RESISTANCE
        && ABS (priv->drag_y - event->y) < DRAG_RESISTANCE)
        return FALSE;

    target_list = create_target_list_for_node (storage_set_view, priv->drag_path);
    if (target_list == NULL)
        return FALSE;

    actions = GDK_ACTION_MOVE | GDK_ACTION_COPY;

    context = e_tree_drag_begin (tree,
                      priv->drag_row, priv->drag_column,
                      target_list, actions,
                      1, (GdkEvent *) event);
    gtk_drag_set_icon_default (context);

    gtk_target_list_unref (target_list);

    return FALSE;
}


/* ETree methods.  */

/* -- Source-side DnD.  */

static void
tree_drag_begin (ETree *etree,
         int row, ETreePath path, int col,
         GdkDragContext *context)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    EFolder *folder;
    EvolutionShellComponentClient *component_client;
    GNOME_Evolution_ShellComponent corba_component;
    GNOME_Evolution_ShellComponentDnd_ActionSet possible_actions;
    GNOME_Evolution_ShellComponentDnd_Action suggested_action;
    CORBA_Environment ev;

    storage_set_view = E_STORAGE_SET_VIEW (etree);
    priv = storage_set_view->priv;

    priv->selected_row_path = e_tree_memory_node_get_data (E_TREE_MEMORY(priv->etree_model), path);

    g_assert (priv->drag_corba_source_interface == CORBA_OBJECT_NIL);

    folder = get_folder_at_node (storage_set_view, path);
    component_client = get_component_at_node (storage_set_view, path);

    if (component_client == NULL)
        return;

    /* Query the `ShellComponentDnd::SourceFolder' interface on the
       component.  */
    /* FIXME we could use the new
       `evolution_shell_component_client_get_dnd_source_interface()'
       call. */

    CORBA_exception_init (&ev);

    corba_component = bonobo_object_corba_objref (BONOBO_OBJECT (component_client));
    priv->drag_corba_source_interface = Bonobo_Unknown_queryInterface (corba_component,
                                       "IDL:GNOME/Evolution/ShellComponentDnd/SourceFolder:1.0",
                                       &ev);
    if (ev._major != CORBA_NO_EXCEPTION
        || priv->drag_corba_source_interface == CORBA_OBJECT_NIL) {
        priv->drag_corba_source_interface = CORBA_OBJECT_NIL;

        CORBA_exception_free (&ev);
        return;
    }

    GNOME_Evolution_ShellComponentDnd_SourceFolder_beginDrag (priv->drag_corba_source_interface,
                                  e_folder_get_physical_uri (folder),
                                  e_folder_get_type_string (folder),
                                  &possible_actions,
                                  &suggested_action,
                                  &ev);

    if (ev._major != CORBA_NO_EXCEPTION) {
        Bonobo_Unknown_unref (priv->drag_corba_source_interface, &ev);
        CORBA_Object_release (priv->drag_corba_source_interface, &ev);

        priv->drag_corba_source_interface = CORBA_OBJECT_NIL;

        CORBA_exception_free (&ev);
        return;
    }

    CORBA_exception_free (&ev);

    if (priv->drag_corba_source_context != NULL)
        CORBA_free (priv->drag_corba_source_context);

    priv->drag_corba_source_context = GNOME_Evolution_ShellComponentDnd_SourceFolder_Context__alloc ();
    priv->drag_corba_source_context->physicalUri     = CORBA_string_dup (e_folder_get_physical_uri (folder));
    priv->drag_corba_source_context->folderType      = CORBA_string_dup (e_folder_get_type_string (folder));
    priv->drag_corba_source_context->possibleActions = possible_actions;
    priv->drag_corba_source_context->suggestedAction = suggested_action;
}

static void
tree_drag_end (ETree *tree,
           int row,
           ETreePath path,
           int col,
           GdkDragContext *context)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    CORBA_Environment ev;

    storage_set_view = E_STORAGE_SET_VIEW (tree);
    priv = storage_set_view->priv;

    if (priv->drag_corba_source_interface == CORBA_OBJECT_NIL)
        return;

    CORBA_exception_init (&ev);

    GNOME_Evolution_ShellComponentDnd_SourceFolder_endDrag (priv->drag_corba_source_interface,
                                priv->drag_corba_source_context,
                                &ev);

    CORBA_free (priv->drag_corba_source_context);
    priv->drag_corba_source_context = NULL;

    Bonobo_Unknown_unref (priv->drag_corba_source_interface, &ev);
    CORBA_Object_release (priv->drag_corba_source_interface, &ev);

    CORBA_exception_free (&ev);
}

static void
tree_drag_data_get (ETree *etree,
            int drag_row,
            ETreePath drag_path,
            int drag_col,
            GdkDragContext *context,
            GtkSelectionData *selection_data,
            unsigned int info,
            guint32 time)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    CORBA_Environment ev;
    char *target_type;

    storage_set_view = E_STORAGE_SET_VIEW (etree);
    priv = storage_set_view->priv;

    switch (info) {
    case E_SHORTCUT_TARGET_TYPE_IDX:
        set_e_shortcut_selection (storage_set_view, selection_data);
        return;
    case EVOLUTION_PATH_TARGET_TYPE_IDX:
        set_evolution_path_selection (storage_set_view, selection_data);
        return;
    }

    g_assert (info > 0);

    if (priv->drag_corba_source_interface == CORBA_OBJECT_NIL)
        return;

    target_type = gdk_atom_name ((GdkAtom) context->targets->data);

    CORBA_exception_init (&ev);

    GNOME_Evolution_ShellComponentDnd_SourceFolder_getData (priv->drag_corba_source_interface,
                                priv->drag_corba_source_context,
                                convert_gdk_drag_action_set_to_corba (context->action),
                                target_type,
                                & priv->drag_corba_data,
                                &ev);

    if (ev._major != CORBA_NO_EXCEPTION)
        gtk_selection_data_set (selection_data, selection_data->target, 8, "", -1);
    else
        gtk_selection_data_set (selection_data,
                    priv->drag_corba_data->target,
                    priv->drag_corba_data->format,
                    priv->drag_corba_data->bytes._buffer,
                    priv->drag_corba_data->bytes._length);

    g_free (target_type);

    CORBA_exception_free (&ev);
}

static void
tree_drag_data_delete (ETree *tree,
               int row,
               ETreePath path,
               int col,
               GdkDragContext *context)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    CORBA_Environment ev;

    storage_set_view = E_STORAGE_SET_VIEW (tree);
    priv = storage_set_view->priv;

    if (priv->drag_corba_source_interface == CORBA_OBJECT_NIL)
        return;

    CORBA_exception_init (&ev);

    GNOME_Evolution_ShellComponentDnd_SourceFolder_deleteData (priv->drag_corba_source_interface,
                                   priv->drag_corba_source_context,
                                   &ev);

    CORBA_exception_free (&ev);
}

/* -- Destination-side DnD.  */

static gboolean
handle_evolution_path_drag_motion (EStorageSetView *storage_set_view,
                   ETreePath path,
                   GdkDragContext *context,
                   unsigned int time)
{
    GdkModifierType modifiers;
    GdkDragAction action;

    gdk_window_get_pointer (NULL, NULL, NULL, &modifiers);

    if ((modifiers & GDK_CONTROL_MASK) != 0)
        action = GDK_ACTION_COPY;
    else
        action = GDK_ACTION_MOVE;

    gdk_drag_status (context, action, time);

    return TRUE;
}

static gboolean
tree_drag_motion (ETree *tree,
          int row,
          ETreePath path,
          int col,
          GdkDragContext *context,
          int x,
          int y,
          unsigned int time)
{
    EStorageSetView *storage_set_view;
    EFolder *folder;
    EStorageSetViewPrivate *priv;
    EvolutionShellComponentClient *component_client;
    GNOME_Evolution_ShellComponentDnd_DestinationFolder destination_folder_interface;
    GNOME_Evolution_ShellComponentDnd_Action suggested_action;
    GNOME_Evolution_ShellComponentDnd_DestinationFolder_Context corba_context;
    CORBA_boolean can_handle;
    CORBA_Environment ev;
    const char *dnd_type;

    storage_set_view = E_STORAGE_SET_VIEW (tree);
    priv = storage_set_view->priv;

    component_client = get_component_at_node (storage_set_view, path);
    if (component_client == NULL)
        return FALSE;

    dnd_type = find_matching_target_for_drag_context (storage_set_view, path, context);
    if (dnd_type == NULL)
        return FALSE;

    g_print ("drag_motion %s\n", dnd_type);

    if (strcmp (dnd_type, EVOLUTION_PATH_TARGET_TYPE) == 0)
        return handle_evolution_path_drag_motion (storage_set_view, path, context, time);

    destination_folder_interface = evolution_shell_component_client_get_dnd_destination_interface (component_client);
    if (destination_folder_interface == NULL)
        return FALSE;

    CORBA_exception_init (&ev);

    corba_context.dndType = (char *) dnd_type; /* (Safe cast, as we don't actually free the corba_context.)  */
    corba_context.possibleActions = convert_gdk_drag_action_set_to_corba (context->actions);
    corba_context.suggestedAction = convert_gdk_drag_action_to_corba (context->suggested_action);

    folder = get_folder_at_node (storage_set_view, path);
    
    can_handle = GNOME_Evolution_ShellComponentDnd_DestinationFolder_handleMotion (destination_folder_interface,
                                               e_folder_get_physical_uri (folder),
                                               &corba_context,
                                               &suggested_action,
                                               &ev);
    if (ev._major != CORBA_NO_EXCEPTION || ! can_handle) {
        CORBA_exception_free (&ev);
        return FALSE;
    }

    CORBA_exception_free (&ev);

    gdk_drag_status (context, convert_corba_drag_action_to_gdk (suggested_action), time);

    return TRUE;
}

static gboolean
tree_drag_drop (ETree *etree,
        int row,
        ETreePath path,
        int col,
        GdkDragContext *context,
        int x,
        int y,
        unsigned int time)
{
    if (context->targets != NULL) {
        gtk_drag_get_data (GTK_WIDGET (etree), context,
                   GPOINTER_TO_INT (context->targets->data),
                   time);
        return TRUE;
    }

    return FALSE;
}

static void
tree_drag_data_received (ETree *etree,
             int row,
             ETreePath path,
             int col,
             GdkDragContext *context,
             int x,
             int y,
             GtkSelectionData *selection_data,
             unsigned int info,
             unsigned int time)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    char *target_type;

    storage_set_view = E_STORAGE_SET_VIEW (etree);
    priv = storage_set_view->priv;

    target_type = gdk_atom_name (selection_data->target);

    if (strcmp (target_type, EVOLUTION_PATH_TARGET_TYPE) == 0) {
        const char *source_path;
        const char *destination_folder_path;
        char *destination_path;

        source_path = (const char *) selection_data->data;
        /* (Basic sanity checks.)  */
        if (source_path == NULL || source_path[0] != G_DIR_SEPARATOR || source_path[1] == '\0')
            return;

        destination_folder_path = e_tree_memory_node_get_data (E_TREE_MEMORY (priv->etree_model), path);
        if (destination_folder_path == NULL)
            return;

        destination_path = g_concat_dir_and_file (destination_folder_path,
                              g_basename (source_path));


        switch (context->action) {
        case GDK_ACTION_MOVE:
            g_print ("EStorageSetView: Moving from `%s' to `%s'\n", source_path, destination_path);
            e_storage_set_async_xfer_folder (priv->storage_set, source_path, destination_path, TRUE,
                             folder_xfer_callback, NULL);
            break;
        case GDK_ACTION_COPY:
            g_print ("EStorageSetView: Copying from `%s' to `%s'\n", source_path, destination_path);
            e_storage_set_async_xfer_folder (priv->storage_set, source_path, destination_path, FALSE,
                             folder_xfer_callback, NULL);
            break;
        default:
            g_warning ("EStorageSetView: Unknown action %d", context->action);
        }

        g_free (destination_path);
    }
    else {
        GNOME_Evolution_ShellComponentDnd_DestinationFolder destination_folder_interface;
        GNOME_Evolution_ShellComponentDnd_DestinationFolder_Context corba_context;
        GNOME_Evolution_ShellComponentDnd_Data corba_data;
        EvolutionShellComponentClient *component_client;
        const char *target_path;

        target_path = e_tree_memory_node_get_data (E_TREE_MEMORY(priv->etree_model), path);

        component_client = get_component_at_node (storage_set_view, path);
        if (component_client != NULL) {
            destination_folder_interface = evolution_shell_component_client_get_dnd_destination_interface (component_client);
            if (destination_folder_interface != NULL) {
                EFolder *folder;
                CORBA_Environment ev;
                CORBA_boolean handled;

                CORBA_exception_init (&ev);


                folder = get_folder_at_node (storage_set_view, path);
    
                corba_context.dndType = (char *) target_type;
                corba_context.possibleActions = convert_gdk_drag_action_set_to_corba (context->actions);
                corba_context.suggestedAction = convert_gdk_drag_action_to_corba (context->suggested_action);

                corba_data.format = selection_data->format;
                corba_data.target = selection_data->target;

                corba_data.bytes._release = FALSE;
                corba_data.bytes._length = selection_data->length;
                corba_data.bytes._buffer = selection_data->data;

                /* pass off the data to the component's DestinationFolderInterface */
                handled = GNOME_Evolution_ShellComponentDnd_DestinationFolder_handleDrop (destination_folder_interface,
                                                      e_folder_get_physical_uri (folder),
                                                      &corba_context,
                                                      convert_gdk_drag_action_to_corba (context->action),
                                                      &corba_data,
                                                      &ev);
            }
        }
    }

    g_free (target_type);
}

static gboolean
right_click (ETree *etree,
         int row,
         ETreePath path,
         int col,
         GdkEvent *event)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;

    storage_set_view = E_STORAGE_SET_VIEW (etree);
    priv = storage_set_view->priv;

    if (priv->container)
        popup_folder_menu (storage_set_view, (GdkEventButton *) event);

    return TRUE;
}

static void
cursor_activated (ETree *tree,
          int row,
          ETreePath path)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;

    storage_set_view = E_STORAGE_SET_VIEW (tree);

    priv = storage_set_view->priv;

    priv->selected_row_path = e_tree_memory_node_get_data (E_TREE_MEMORY (priv->etree_model), path);

    if (e_tree_model_node_depth (priv->etree_model, path) >= 2) {
        /* it was a folder */
        gtk_signal_emit (GTK_OBJECT (storage_set_view), signals[FOLDER_SELECTED],
                 priv->selected_row_path);
    } else {
        /* it was a storage */
        gtk_signal_emit (GTK_OBJECT (storage_set_view), signals[STORAGE_SELECTED],
                 priv->selected_row_path + 1);
    }
}


/* ETreeModel Methods */

static GdkPixbuf*
etree_icon_at (ETreeModel *etree,
           ETreePath tree_path,
           void *model_data)
{
    EFolderTypeRegistry *folder_type_registry;
    EStorageSetView *storage_set_view;
    EStorageSet *storage_set;
    GdkPixbuf *icon_pixbuf;
    EFolder *folder;
    char *path;
    int depth;

    /* folders are from depth 2 on.  depth 1 are storages and 0 is
           our My Evolution root node. */
    depth = e_tree_model_node_depth (etree, tree_path);

    if (depth == 0) {
        /* My Evolution */
        storage_set_view = E_STORAGE_SET_VIEW (model_data);
        storage_set = storage_set_view->priv->storage_set;
        
        folder_type_registry = e_storage_set_get_folder_type_registry (storage_set);
        
        icon_pixbuf = e_folder_type_registry_get_icon_for_type (folder_type_registry,
                                    "My Evolution", TRUE);
        return icon_pixbuf;
    } else if (depth >= 2) {
        storage_set_view = E_STORAGE_SET_VIEW (model_data);
        storage_set = storage_set_view->priv->storage_set;
        
        path = (char*)e_tree_memory_node_get_data (E_TREE_MEMORY(etree), tree_path);
        
        folder = e_storage_set_get_folder (storage_set, path);
        if (folder == NULL)
            return NULL;
        
        return get_pixbuf_for_folder (storage_set_view, folder);
    }

    return NULL;
}

/* This function returns the number of columns in our ETreeModel. */
static int
etree_column_count (ETreeModel *etc, void *data)
{
    return 2;
}

static gboolean
etree_has_save_id (ETreeModel *etm, void *data)
{
    return TRUE;
}

static gchar *
etree_get_save_id (ETreeModel *etm, ETreePath node, void *model_data)
{
    return g_strdup(e_tree_memory_node_get_data (E_TREE_MEMORY(etm), node));
}

static gboolean
etree_has_get_node_by_id (ETreeModel *etm, void *data)
{
    return TRUE;
}

static ETreePath
etree_get_node_by_id (ETreeModel *etm, gchar *save_id, void *model_data)
{
    EStorageSetView *storage_set_view;
    storage_set_view = E_STORAGE_SET_VIEW (model_data);

    return g_hash_table_lookup (storage_set_view->priv->path_to_etree_node, save_id);
}

static void *
etree_value_at (ETreeModel *etree, ETreePath tree_path, int col, void *model_data)
{
    EStorageSetView *storage_set_view;
    EStorageSet *storage_set;
    EStorage *storage;
    EFolder *folder;
    char *path;

    storage_set_view = E_STORAGE_SET_VIEW (model_data);
    storage_set = storage_set_view->priv->storage_set;

    path = (char *) e_tree_memory_node_get_data (E_TREE_MEMORY(etree), tree_path);

    folder = e_storage_set_get_folder (storage_set, path);
    if (folder != NULL) {
        if (col == 0)
            return (void *) e_folder_get_name (folder);
        else
            return (void *) e_folder_get_highlighted (folder);
    }

    storage = e_storage_set_get_storage (storage_set, path + 1);
    if (storage != NULL && col == 0)
        return (void *) e_storage_get_name (storage);

    return _("My Evolution");
}

static void
etree_set_value_at (ETreeModel *etree, ETreePath path, int col, const void *val, void *model_data)
{
    /* nada */
}

static gboolean
etree_is_editable (ETreeModel *etree, ETreePath path, int col, void *model_data)
{
    return FALSE;
}


/* This function duplicates the value passed to it. */
static void *
etree_duplicate_value (ETreeModel *etc, int col, const void *value, void *data)
{
    if (col == 0)
        return g_strdup (value);
    else
        return (void *)value;
}

/* This function frees the value passed to it. */
static void
etree_free_value (ETreeModel *etc, int col, void *value, void *data)
{
    if (col == 0)
        g_free (value);
}

/* This function creates an empty value. */
static void *
etree_initialize_value (ETreeModel *etc, int col, void *data)
{
    if (col == 0)
        return g_strdup ("");
    else
        return NULL;
}

/* This function reports if a value is empty. */
static gboolean
etree_value_is_empty (ETreeModel *etc, int col, const void *value, void *data)
{
    if (col == 0)
        return !(value && *(char *)value);
    else
        return !value;
}

/* This function reports if a value is empty. */
static char *
etree_value_to_string (ETreeModel *etc, int col, const void *value, void *data)
{
    if (col == 0)
        return g_strdup(value);
    else
        return g_strdup(value ? "Yes" : "No");
}


/* StorageSet signal handling.  */

static void
new_storage_cb (EStorageSet *storage_set,
        EStorage *storage,
        void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETreePath node;
    char *path;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;

    path = g_strconcat (G_DIR_SEPARATOR_S, e_storage_get_name (storage), NULL);

    node = e_tree_memory_node_insert (E_TREE_MEMORY(priv->etree_model),
                      priv->root_node,
                      -1, path);
    e_tree_memory_sort_node (E_TREE_MEMORY(priv->etree_model), priv->root_node, storage_sort_callback, storage_set_view);

    if (! add_node_to_hash (storage_set_view, path, node)) {
        e_tree_memory_node_remove (E_TREE_MEMORY(priv->etree_model), node);
        return;
    }
}

static void
removed_storage_cb (EStorageSet *storage_set,
            EStorage *storage,
            void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETreeModel *etree;
    ETreePath node;
    char *path;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;
    etree = priv->etree_model;

    path = g_strconcat (G_DIR_SEPARATOR_S, e_storage_get_name (storage), NULL);
    node = remove_node_from_hash (storage_set_view, path);
    g_free (path);

    e_tree_memory_node_remove (E_TREE_MEMORY(etree), node);
}

static void
new_folder_cb (EStorageSet *storage_set,
           const char *path,
           void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETreeModel *etree;
    ETreePath parent_node;
    ETreePath new_node;
    const char *last_separator;
    char *parent_path;
    char *copy_of_path;

    g_return_if_fail (g_path_is_absolute (path));

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;
    etree = priv->etree_model;

    last_separator = strrchr (path, G_DIR_SEPARATOR);

    parent_path = g_strndup (path, last_separator - path);
    parent_node = g_hash_table_lookup (priv->path_to_etree_node, parent_path);
    if (parent_node == NULL) {
        g_warning ("EStorageSetView: EStorageSet reported new subfolder for non-existing folder -- %s",
               parent_path);
        g_free (parent_path);
        return;
    }

    g_free (parent_path);

    copy_of_path = g_strdup (path);
    new_node = e_tree_memory_node_insert (E_TREE_MEMORY(etree), parent_node, -1, copy_of_path);
    e_tree_memory_sort_node(E_TREE_MEMORY(etree), parent_node, folder_sort_callback, storage_set_view);

    if (! add_node_to_hash (storage_set_view, path, new_node)) {
        e_tree_memory_node_remove (E_TREE_MEMORY(etree), new_node);
        return;
    }
}

static void
updated_folder_cb (EStorageSet *storage_set,
           const char *path,
           void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETreeModel *etree;
    ETreePath node;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;
    etree = priv->etree_model;

    node = lookup_node_in_hash (storage_set_view, path);
    e_tree_model_node_data_changed (etree, node);
}

static void
removed_folder_cb (EStorageSet *storage_set,
           const char *path,
           void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    ETreeModel *etree;
    ETreePath node;

    storage_set_view = E_STORAGE_SET_VIEW (data);
    priv = storage_set_view->priv;
    etree = priv->etree_model;

    node = remove_node_from_hash (storage_set_view, path);
    e_tree_memory_node_remove (E_TREE_MEMORY(etree), node);
}


static void
class_init (EStorageSetViewClass *klass)
{
    GtkObjectClass *object_class;
    ETreeClass *etree_class;
    GtkWidgetClass *widget_class;

    parent_class = gtk_type_class (e_tree_get_type ());

    object_class = GTK_OBJECT_CLASS (klass);
    object_class->destroy = destroy;

    widget_class = GTK_WIDGET_CLASS (klass);
    widget_class->button_press_event  = button_press_event;
    widget_class->motion_notify_event = motion_notify_event;

    etree_class = E_TREE_CLASS (klass);
    etree_class->right_click             = right_click;
    etree_class->cursor_activated        = cursor_activated;
    etree_class->tree_drag_begin         = tree_drag_begin;
    etree_class->tree_drag_end           = tree_drag_end;
    etree_class->tree_drag_data_get      = tree_drag_data_get;
    etree_class->tree_drag_data_delete   = tree_drag_data_delete;
    etree_class->tree_drag_motion        = tree_drag_motion;
    etree_class->tree_drag_drop          = tree_drag_drop;
    etree_class->tree_drag_data_received = tree_drag_data_received;

    signals[FOLDER_SELECTED]
        = gtk_signal_new ("folder_selected",
                  GTK_RUN_FIRST,
                  object_class->type,
                  GTK_SIGNAL_OFFSET (EStorageSetViewClass, folder_selected),
                  gtk_marshal_NONE__STRING,
                  GTK_TYPE_NONE, 1,
                  GTK_TYPE_STRING);

    signals[STORAGE_SELECTED]
        = gtk_signal_new ("storage_selected",
                  GTK_RUN_FIRST,
                  object_class->type,
                  GTK_SIGNAL_OFFSET (EStorageSetViewClass, storage_selected),
                  gtk_marshal_NONE__STRING,
                  GTK_TYPE_NONE, 1,
                  GTK_TYPE_STRING);

    signals[DND_ACTION]
        = gtk_signal_new ("dnd_action",
                  GTK_RUN_FIRST,
                  object_class->type,
                  GTK_SIGNAL_OFFSET (EStorageSetViewClass, dnd_action),
                  marshal_NONE__GDKDRAGCONTEXT_STRING_STRING_STRING,
                  GTK_TYPE_NONE, 4,
                  GTK_TYPE_GDK_DRAG_CONTEXT,
                  GTK_TYPE_STRING,
                  GTK_TYPE_STRING,
                  GTK_TYPE_STRING);

    gtk_object_class_add_signals (object_class, signals, LAST_SIGNAL);
}

static void
init (EStorageSetView *storage_set_view)
{
    EStorageSetViewPrivate *priv;

    priv = g_new (EStorageSetViewPrivate, 1);

    priv->storage_set                 = NULL;
    priv->path_to_etree_node          = g_hash_table_new (g_str_hash, g_str_equal);
    priv->type_name_to_pixbuf         = g_hash_table_new (g_str_hash, g_str_equal);
    priv->selected_row_path           = NULL;
    priv->show_folders                = TRUE;

    priv->drag_corba_source_interface = CORBA_OBJECT_NIL;

    priv->drag_corba_source_context   = NULL;
    priv->drag_corba_data             = NULL;

    priv->drag_x                      = 0;
    priv->drag_y                      = 0;
    priv->drag_column                 = 0;
    priv->drag_row                    = 0;

    storage_set_view->priv = priv;
}


/* Handling of the "changed" signal in EFolders displayed in the EStorageSetView.  */

struct _FolderChangedCallbackData {
    EStorageSetView *storage_set_view;
    char *path;
};
typedef struct _FolderChangedCallbackData FolderChangedCallbackData;

static void
folder_changed_callback_data_destroy_notify (void *data)
{
    FolderChangedCallbackData *callback_data;

    callback_data = (FolderChangedCallbackData *) data;

    g_free (callback_data->path);
    g_free (callback_data);
}

static void
folder_changed_cb (EFolder *folder,
           void *data)
{
    EStorageSetView *storage_set_view;
    EStorageSetViewPrivate *priv;
    FolderChangedCallbackData *callback_data;
    ETreePath node;

    callback_data = (FolderChangedCallbackData *) data;

    storage_set_view = callback_data->storage_set_view;
    priv = callback_data->storage_set_view->priv;

    node = g_hash_table_lookup (priv->path_to_etree_node, callback_data->path);
    if (node == NULL) {
        g_warning ("EStorageSetView -- EFolder::changed emitted for a folder whose path I don't know.");
        return;
    }

    e_tree_model_node_data_changed (priv->etree_model, node);
}


static void
insert_folders (EStorageSetView *storage_set_view,
        ETreePath parent,
        EStorage *storage,
        const char *path)
{
    EStorageSetViewPrivate *priv;
    ETreeModel *etree;
    ETreePath node;
    GList *folder_path_list;
    GList *p;
    const char *storage_name;

    priv = storage_set_view->priv;
    etree = priv->etree_model;

    storage_name = e_storage_get_name (storage);

    folder_path_list = e_storage_get_subfolder_paths (storage, path);
    if (folder_path_list == NULL)
        return;

    for (p = folder_path_list; p != NULL; p = p->next) {
        FolderChangedCallbackData *folder_changed_callback_data;
        EFolder *folder;
        const char *folder_name;
        const char *folder_path;
        char *full_path;

        folder_path = (const char *) p->data;
        folder = e_storage_get_folder (storage, folder_path);
        folder_name = e_folder_get_name (folder);

        full_path = g_strconcat ("/", storage_name, folder_path, NULL);
        node = e_tree_memory_node_insert (E_TREE_MEMORY(etree), parent, -1, (void *) full_path);
        e_tree_memory_sort_node(E_TREE_MEMORY(etree), parent, folder_sort_callback, storage_set_view);
        add_node_to_hash (storage_set_view, full_path, node);

        insert_folders (storage_set_view, node, storage, folder_path);

        folder_changed_callback_data = g_new (FolderChangedCallbackData, 1);
        folder_changed_callback_data->storage_set_view = storage_set_view;
        folder_changed_callback_data->path = g_strdup (full_path);

        e_gtk_signal_connect_full_while_alive (GTK_OBJECT (folder), "changed",
                               GTK_SIGNAL_FUNC (folder_changed_cb),
                               NULL,
                               folder_changed_callback_data,
                               folder_changed_callback_data_destroy_notify,
                               FALSE, FALSE,
                               GTK_OBJECT (storage_set_view));
    }

    e_free_string_list (folder_path_list);
}

static void
insert_storages (EStorageSetView *storage_set_view)
{
    EStorageSetViewPrivate *priv;
    EStorageSet *storage_set;
    GList *storage_list;
    GList *p;

    priv = storage_set_view->priv;

    storage_set = priv->storage_set;

    storage_list = e_storage_set_get_storage_list (storage_set);

    for (p = storage_list; p != NULL; p = p->next) {
        EStorage *storage = E_STORAGE (p->data);
        const char *name;
        char *path;
        ETreePath parent;

        name = e_storage_get_name (storage);
        path = g_strconcat ("/", name, NULL);

        parent = e_tree_memory_node_insert (E_TREE_MEMORY(priv->etree_model), priv->root_node,
                            -1, path);
        e_tree_memory_sort_node (E_TREE_MEMORY(priv->etree_model), priv->root_node, storage_sort_callback, storage_set_view);

        g_hash_table_insert (priv->path_to_etree_node, path, parent);

        if (priv->show_folders)
            insert_folders (storage_set_view, parent, storage, "/");
    }

    e_free_object_list (storage_list);
}

void
e_storage_set_view_construct (EStorageSetView   *storage_set_view,
                  EStorageSet       *storage_set,
                  BonoboUIContainer *container)
{
    EStorageSetViewPrivate *priv;
    ETableExtras *extras;
    ECell *cell;

    g_return_if_fail (storage_set_view != NULL);
    g_return_if_fail (E_IS_STORAGE_SET_VIEW (storage_set_view));
    g_return_if_fail (storage_set != NULL);
    g_return_if_fail (E_IS_STORAGE_SET (storage_set));

    priv = storage_set_view->priv;

    priv->container = container;

    priv->etree_model = e_tree_memory_callbacks_new (etree_icon_at,

                             etree_column_count,

                             etree_has_save_id,
                             etree_get_save_id,
                             etree_has_get_node_by_id,
                             etree_get_node_by_id,

                             etree_value_at,
                             etree_set_value_at,
                             etree_is_editable,

                             etree_duplicate_value,
                             etree_free_value,
                             etree_initialize_value,
                             etree_value_is_empty,
                             etree_value_to_string,

                             storage_set_view);

    e_tree_memory_set_node_destroy_func (E_TREE_MEMORY (priv->etree_model), (GFunc) g_free, NULL);
    e_tree_memory_set_expanded_default (E_TREE_MEMORY (priv->etree_model), TRUE);

    priv->root_node = e_tree_memory_node_insert (E_TREE_MEMORY(priv->etree_model), NULL, -1, g_strdup ("/My Evolution"));

    extras = e_table_extras_new ();
    cell = e_cell_text_new (NULL, GTK_JUSTIFY_LEFT);
    gtk_object_set (GTK_OBJECT (cell), "bold_column", 1, NULL);
    e_table_extras_add_cell (extras, "render_tree",
                 e_cell_tree_new (NULL, NULL, TRUE, cell));

    e_tree_construct_from_spec_file (E_TREE (storage_set_view), priv->etree_model, extras,
                     EVOLUTION_ETSPECDIR "/e-storage-set-view.etspec", NULL);

    e_tree_root_node_set_visible (E_TREE(storage_set_view), TRUE);

    gtk_object_unref (GTK_OBJECT (extras));

    gtk_object_ref (GTK_OBJECT (storage_set));
    priv->storage_set = storage_set;

    e_tree_drag_dest_set (E_TREE (storage_set_view), 0, NULL, 0, GDK_ACTION_MOVE | GDK_ACTION_COPY);

    gtk_signal_connect_while_alive (GTK_OBJECT (storage_set), "new_storage",
                    GTK_SIGNAL_FUNC (new_storage_cb), storage_set_view,
                    GTK_OBJECT (storage_set_view));
    gtk_signal_connect_while_alive (GTK_OBJECT (storage_set), "removed_storage",
                    GTK_SIGNAL_FUNC (removed_storage_cb), storage_set_view,
                    GTK_OBJECT (storage_set_view));
    gtk_signal_connect_while_alive (GTK_OBJECT (storage_set), "new_folder",
                    GTK_SIGNAL_FUNC (new_folder_cb), storage_set_view,
                    GTK_OBJECT (storage_set_view));
    gtk_signal_connect_while_alive (GTK_OBJECT (storage_set), "updated_folder",
                    GTK_SIGNAL_FUNC (updated_folder_cb), storage_set_view,
                    GTK_OBJECT (storage_set_view));
    gtk_signal_connect_while_alive (GTK_OBJECT (storage_set), "removed_folder",
                    GTK_SIGNAL_FUNC (removed_folder_cb), storage_set_view,
                    GTK_OBJECT (storage_set_view));

    insert_storages (storage_set_view);
}

GtkWidget *
e_storage_set_view_new (EStorageSet *storage_set,
            BonoboUIContainer *container)
{
    GtkWidget *new;

    g_return_val_if_fail (storage_set != NULL, NULL);
    g_return_val_if_fail (E_IS_STORAGE_SET (storage_set), NULL);

    new = gtk_type_new (e_storage_set_view_get_type ());
    e_storage_set_view_construct (E_STORAGE_SET_VIEW (new), storage_set, container);

    return new;
}


void
e_storage_set_view_set_current_folder (EStorageSetView *storage_set_view,
                       const char *path)
{
    EStorageSetViewPrivate *priv;
    ETreePath node;

    g_return_if_fail (storage_set_view != NULL);
    g_return_if_fail (E_IS_STORAGE_SET_VIEW (storage_set_view));
    g_return_if_fail (path != NULL && g_path_is_absolute (path));

    priv = storage_set_view->priv;

    node = g_hash_table_lookup (priv->path_to_etree_node, path);
    if (node == NULL) {
        return;
    }

    e_tree_show_node (E_TREE(storage_set_view), node);
    e_tree_set_cursor (E_TREE (storage_set_view), node);

    gtk_signal_emit (GTK_OBJECT (storage_set_view), signals[FOLDER_SELECTED], path);
}

const char *
e_storage_set_view_get_current_folder (EStorageSetView *storage_set_view)
{
    EStorageSetViewPrivate *priv;
    ETreePath etree_node;
    const char *path;

    g_return_val_if_fail (storage_set_view != NULL, NULL);
    g_return_val_if_fail (E_IS_STORAGE_SET_VIEW (storage_set_view), NULL);

    priv = storage_set_view->priv;

    if (!priv->show_folders)
        return NULL; /* Mmh! */

    etree_node = e_tree_get_cursor (E_TREE (storage_set_view));

    if (etree_node == NULL)
        return NULL;    /* Mmh? */

    path = (char*)e_tree_memory_node_get_data(E_TREE_MEMORY(priv->etree_model), etree_node);

    return path;
}

void
e_storage_set_view_set_show_folders (EStorageSetView *storage_set_view,
                     gboolean show)
{
    EStorageSetViewPrivate *priv;

    g_return_if_fail (storage_set_view != NULL);
    g_return_if_fail (E_IS_STORAGE_SET_VIEW (storage_set_view));

    priv = storage_set_view->priv;

    if (show == priv->show_folders)
        return;

    /* tear down existing tree and hash table mappings */
    e_tree_memory_node_remove (E_TREE_MEMORY(priv->etree_model), priv->root_node);

    /* now re-add the root node */
    priv->root_node = e_tree_memory_node_insert (E_TREE_MEMORY(priv->etree_model), NULL, -1, g_strdup ("/My Evolution"));

    /* then reinsert the storages after setting the "show_folders"
       flag.  insert_storages will call insert_folders if
       show_folders is TRUE */

    priv->show_folders = show;
    insert_storages (storage_set_view);
}

gboolean
e_storage_set_view_get_show_folders (EStorageSetView *storage_set_view)
{
    return storage_set_view->priv->show_folders;
}


E_MAKE_TYPE (e_storage_set_view, "EStorageSetView", EStorageSetView, class_init, init, PARENT_TYPE)