path: root/widgets/menus/gal-view-collection.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * gal-view-collection.c
 * Copyright 2000, 2001, Ximian, Inc.
 *
 * Authors:
 *   Chris Lahey <clahey@ximian.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License, version 2, as published by the Free Software Foundation.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

#include <config.h>

#include <ctype.h>
#include <string.h>
#include <errno.h>

#include <glib.h>
#include <libxml/parser.h>
#include <libgnome/gnome-util.h>
#include <libedataserver/e-xml-utils.h>

#include <glib/gi18n.h>
#include "e-util/e-util.h"
#include "e-util/e-xml-utils.h"
#include "misc/e-unicode.h"

#include "gal-view-collection.h"

#define PARENT_TYPE G_TYPE_OBJECT

static GObjectClass *gal_view_collection_parent_class;

#define d(x)

enum {
    DISPLAY_VIEW,
    CHANGED,
    LAST_SIGNAL
};

static guint gal_view_collection_signals [LAST_SIGNAL] = { 0, };

/**
 * gal_view_collection_display_view:
 * @collection: The GalViewCollection to send the signal on.
 * @view: The view to display.
 *
 */
void
gal_view_collection_display_view (GalViewCollection *collection,
                  GalView *view)
{
    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (view != NULL);
    g_return_if_fail (GAL_IS_VIEW (view));

    g_signal_emit (collection,
               gal_view_collection_signals [DISPLAY_VIEW], 0,
               view);
}

static void
gal_view_collection_changed (GalViewCollection *collection)
{
    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));

    g_signal_emit (collection,
               gal_view_collection_signals [CHANGED], 0);
}

static void
gal_view_collection_item_free (GalViewCollectionItem *item)
{
    g_free(item->id);
    if (item->view) {
        if (item->view_changed_id)
            g_signal_handler_disconnect (item->view,
                             item->view_changed_id);
        g_object_unref(item->view);
    }
    g_free(item);
}

static char *
gal_view_generate_string (GalViewCollection *collection,
              GalView           *view,
              int which)
{
    char *ret_val;
    char *pointer;

    if (which == 1)
        ret_val = g_strdup(gal_view_get_title(view));
    else
        ret_val = g_strdup_printf("%s_%d", gal_view_get_title(view), which);
    for (pointer = ret_val; *pointer; pointer = g_utf8_next_char(pointer)) {
        if (!g_unichar_isalnum(g_utf8_get_char(pointer))) {
            char *ptr = pointer;
            for (; ptr < g_utf8_next_char(pointer); *ptr = '_', ptr++)
                ;
        }
    }
    return ret_val;
}

static gint
gal_view_check_string (GalViewCollection *collection,
               char *string)
{
    int i;

    if (!strcmp (string, "current_view"))
        return FALSE;

    for (i = 0; i < collection->view_count; i++) {
        if (!strcmp(string, collection->view_data[i]->id))
            return FALSE;
    }
    for (i = 0; i < collection->removed_view_count; i++) {
        if (!strcmp(string, collection->removed_view_data[i]->id))
            return FALSE;
    }
    return TRUE;
}

static char *
gal_view_generate_id (GalViewCollection *collection,
              GalView           *view)
{
    int i;
    for (i = 1; TRUE; i++) {
        char *try;

        try = gal_view_generate_string(collection, view, i);
        if (gal_view_check_string(collection, try))
            return try;
        g_free(try);
    }
}

static void
gal_view_collection_dispose (GObject *object)
{
    GalViewCollection *collection = GAL_VIEW_COLLECTION(object);
    int i;

    for (i = 0; i < collection->view_count; i++) {
        gal_view_collection_item_free (collection->view_data[i]);
    }
    g_free (collection->view_data);
    collection->view_data = NULL;
    collection->view_count = 0;

    g_list_foreach (
        collection->factory_list,
        (GFunc) g_object_unref, NULL);
    g_list_free (collection->factory_list);
    collection->factory_list = NULL;

    for (i = 0; i < collection->removed_view_count; i++) {
        gal_view_collection_item_free (collection->removed_view_data[i]);
    }
    g_free(collection->removed_view_data);
    collection->removed_view_data  = NULL;
    collection->removed_view_count = 0;

    g_free(collection->system_dir);
    collection->system_dir = NULL;

    g_free(collection->local_dir);
    collection->local_dir = NULL;

    g_free (collection->default_view);
    collection->default_view = NULL;

    g_free (collection->title);
    collection->title = NULL;

    if (gal_view_collection_parent_class->dispose)
        (*gal_view_collection_parent_class->dispose)(object);
}

static void
gal_view_collection_class_init (GObjectClass *object_class)
{
    GalViewCollectionClass *klass = GAL_VIEW_COLLECTION_CLASS(object_class);
    gal_view_collection_parent_class = g_type_class_ref (PARENT_TYPE);
    
    object_class->dispose = gal_view_collection_dispose;

    gal_view_collection_signals [DISPLAY_VIEW] =
        g_signal_new ("display_view",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (GalViewCollectionClass, display_view),
                  NULL, NULL,
                  g_cclosure_marshal_VOID__OBJECT,
                  G_TYPE_NONE, 1, GAL_VIEW_TYPE);

    gal_view_collection_signals [CHANGED] =
        g_signal_new ("changed",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (GalViewCollectionClass, changed),
                  NULL, NULL,
                  g_cclosure_marshal_VOID__VOID,
                  G_TYPE_NONE, 0);

    klass->display_view = NULL;
    klass->changed      = NULL;
}

static void
gal_view_collection_init (GalViewCollection *collection)
{
    collection->view_data             = NULL;
    collection->view_count            = 0;
    collection->factory_list          = NULL;

    collection->removed_view_data     = NULL;
    collection->removed_view_count    = 0;

    collection->system_dir            = NULL;
    collection->local_dir             = NULL;

    collection->loaded                = FALSE;
    collection->default_view          = NULL;
    collection->default_view_built_in = TRUE;

    collection->title                 = NULL;
}

E_MAKE_TYPE(gal_view_collection, "GalViewCollection", GalViewCollection, gal_view_collection_class_init, gal_view_collection_init, PARENT_TYPE)

/**
 * gal_view_collection_new:
 *
 * A collection of views and view factories.
 */
GalViewCollection *
gal_view_collection_new                      (void)
{
    return g_object_new (GAL_VIEW_COLLECTION_TYPE, NULL);
}

void
gal_view_collection_set_title (GalViewCollection *collection,
                   const char *title)
{
    g_free (collection->title);
    collection->title = g_strdup (title);
}

/**
 * gal_view_collection_set_storage_directories
 * @collection: The view collection to initialize
 * @system_dir: The location of the system built in views
 * @local_dir: The location to store the users set up views
 *
 * Sets up the GalViewCollection.
 */
void
gal_view_collection_set_storage_directories  (GalViewCollection *collection,
                          const char        *system_dir,
                          const char        *local_dir)
{
    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (system_dir != NULL);
    g_return_if_fail (local_dir != NULL);

    g_free(collection->system_dir);
    g_free(collection->local_dir);

    collection->system_dir = g_strdup(system_dir);
    collection->local_dir = g_strdup(local_dir);
}

/**
 * gal_view_collection_add_factory
 * @collection: The view collection to add a factory to
 * @factory: The factory to add.  The @collection will add a reference
 * to the factory object, so you should unref it after calling this
 * function if you no longer need it.
 *
 * Adds the given factory to this collection.  This list is used both
 * when loading views from their xml description as well as when the
 * user tries to create a new view.
 */
void
gal_view_collection_add_factory              (GalViewCollection *collection,
                          GalViewFactory    *factory)
{
    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (factory != NULL);
    g_return_if_fail (GAL_IS_VIEW_FACTORY (factory));

    g_object_ref (factory);
    collection->factory_list = g_list_prepend (collection->factory_list, factory);
}

static void
view_changed (GalView *view,
          GalViewCollectionItem *item)
{
    item->changed = TRUE;
    item->ever_changed = TRUE;

    g_signal_handler_block(G_OBJECT(item->view), item->view_changed_id);
    gal_view_collection_changed(item->collection);
    g_signal_handler_unblock(G_OBJECT(item->view), item->view_changed_id);
}

/* Use factory list to load a GalView file. */
static GalView *
gal_view_collection_real_load_view_from_file (GalViewCollection *collection, const char *type, const char *title, const char *dir, const char *filename)
{
    GalViewFactory *factory;
    GList *factories;

    factory = NULL;
    for (factories = collection->factory_list; factories; factories = factories->next) {
        if (type && !strcmp(gal_view_factory_get_type_code(factories->data), type)) {
            factory = factories->data;
            break;
        }
    }
    if (factory) {
        GalView *view;

        view = gal_view_factory_new_view (factory, title);
        gal_view_set_title (view, title);
        gal_view_load(view, filename);
        return view;
    }
    return NULL;
}

GalView *
gal_view_collection_load_view_from_file (GalViewCollection *collection, const char *type, const char *filename)
{
    return gal_view_collection_real_load_view_from_file (collection, type, "", collection->local_dir, filename);
}

static GalViewCollectionItem *
load_single_file (GalViewCollection *collection,
          gchar *dir,
          gboolean local,
          xmlNode *node)
{
    GalViewCollectionItem *item;
    item = g_new(GalViewCollectionItem, 1);
    item->ever_changed = local;
    item->changed = FALSE;
    item->built_in = !local;
    item->id = e_xml_get_string_prop_by_name(node, (const unsigned char *)"id");
    item->filename = e_xml_get_string_prop_by_name(node, (const unsigned char *)"filename");
    item->title = e_xml_get_translated_utf8_string_prop_by_name(node, (const unsigned char *)"title");
    item->type = e_xml_get_string_prop_by_name(node, (const unsigned char *)"type");
    item->collection = collection;
    item->view_changed_id = 0;

    if (item->filename) {
        char *fullpath;
        fullpath = g_build_filename(dir, item->filename, NULL);
        item->view = gal_view_collection_real_load_view_from_file (collection, item->type, item->title, dir, fullpath);
        g_free(fullpath);
        if (item->view) {
            item->view_changed_id =
                g_signal_connect(item->view, "changed",
                         G_CALLBACK(view_changed), item);
        }
    }
    return item;
}

static void
load_single_dir (GalViewCollection *collection,
         char *dir,
         gboolean local)
{
    xmlDoc *doc = NULL;
    xmlNode *root;
    xmlNode *child;
    char *filename = g_build_filename(dir, "galview.xml", NULL);
    char *default_view;
    
    if (g_file_test (filename, G_FILE_TEST_IS_REGULAR)) {
#ifdef G_OS_WIN32
        gchar *locale_filename = g_win32_locale_filename_from_utf8 (filename);
        if (locale_filename != NULL)
            doc = xmlParseFile (locale_filename);
        g_free (locale_filename);
#else
        doc = xmlParseFile (filename);
#endif
    }
    
    if (!doc) {
        g_free (filename);
        return;
    }
    root = xmlDocGetRootElement(doc);
    for (child = root->xmlChildrenNode; child; child = child->next) {
        gchar *id;
        gboolean found = FALSE;
        int i;

        if (!strcmp ((char *)child->name, "text"))
            continue;

        id = e_xml_get_string_prop_by_name(child, (const unsigned char *)"id");
        for (i = 0; i < collection->view_count; i++) {
            if (!strcmp(id, collection->view_data[i]->id)) {
                if (!local)
                    collection->view_data[i]->built_in = TRUE;
                found = TRUE;
                break;
            }
        }
        if (!found) {
            for (i = 0; i < collection->removed_view_count; i++) {
                if (!strcmp(id, collection->removed_view_data[i]->id)) {
                    if (!local)
                        collection->removed_view_data[i]->built_in = TRUE;
                    found = TRUE;
                    break;
                }
            }
        }

        if (!found) {
            GalViewCollectionItem *item = load_single_file (collection, dir, local, child);
            if (item->filename && *item->filename) {
                collection->view_data = g_renew(GalViewCollectionItem *, collection->view_data, collection->view_count + 1);
                collection->view_data[collection->view_count] = item;
                collection->view_count ++;
            } else {
                collection->removed_view_data = g_renew(GalViewCollectionItem *, collection->removed_view_data, collection->removed_view_count + 1);
                collection->removed_view_data[collection->removed_view_count] = item;
                collection->removed_view_count ++;
            }
        }
        g_free(id);
    }

    default_view = e_xml_get_string_prop_by_name (root, (const unsigned char *)"default-view");
    if (default_view) {
        if (local)
            collection->default_view_built_in = FALSE;
        else
            collection->default_view_built_in = TRUE;
        g_free (collection->default_view);
        collection->default_view = default_view;
    }

    g_free(filename);
    xmlFreeDoc(doc);
}

/**
 * gal_view_collection_load
 * @collection: The view collection to load information for
 *
 * Loads the data from the system and user directories specified in
 * set storage directories.  This is primarily for internal use by
 * other parts of gal_view.
 */
void
gal_view_collection_load              (GalViewCollection *collection)
{
    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (collection->local_dir != NULL);
    g_return_if_fail (collection->system_dir != NULL);
    g_return_if_fail (!collection->loaded);

    if ((g_mkdir_with_parents (collection->local_dir, 0777) == -1) && (errno != EEXIST))
        g_warning ("Unable to create dir %s: %s", collection->local_dir, g_strerror(errno));

    load_single_dir(collection, collection->local_dir, TRUE);
    load_single_dir(collection, collection->system_dir, FALSE);
    gal_view_collection_changed(collection);

    collection->loaded = TRUE;
}

/**
 * gal_view_collection_save
 * @collection: The view collection to save information for
 *
 * Saves the data to the user directory specified in set storage
 * directories.  This is primarily for internal use by other parts of
 * gal_view.
 */
void
gal_view_collection_save              (GalViewCollection *collection)
{
    int i;
    xmlDoc *doc;
    xmlNode *root;
    char *filename;

    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (collection->local_dir != NULL);

    doc = xmlNewDoc((const unsigned char *)"1.0");
    root = xmlNewNode(NULL, (const unsigned char *)"GalViewCollection");
    xmlDocSetRootElement(doc, root);

    if (collection->default_view && !collection->default_view_built_in) {
        e_xml_set_string_prop_by_name(root, (const unsigned char *)"default-view", collection->default_view);
    }

    for (i = 0; i < collection->view_count; i++) {
        xmlNode *child;
        GalViewCollectionItem *item;

        item = collection->view_data[i];
        if (item->ever_changed) {
            child = xmlNewChild(root, NULL, (const unsigned char *)"GalView", NULL);
            e_xml_set_string_prop_by_name(child, (const unsigned char *)"id", item->id);
            e_xml_set_string_prop_by_name(child, (const unsigned char *)"title", item->title);
            e_xml_set_string_prop_by_name(child, (const unsigned char *)"filename", item->filename);
            e_xml_set_string_prop_by_name(child, (const unsigned char *)"type", item->type);

            if (item->changed) {
                filename = g_build_filename(collection->local_dir, item->filename, NULL);
                gal_view_save(item->view, filename);
                g_free(filename);
            }
        }
    }
    for (i = 0; i < collection->removed_view_count; i++) {
        xmlNode *child;
        GalViewCollectionItem *item;

        item = collection->removed_view_data[i];

        child = xmlNewChild(root, NULL, (const unsigned char *)"GalView", NULL);
        e_xml_set_string_prop_by_name(child, (const unsigned char *)"id", item->id);
        e_xml_set_string_prop_by_name(child, (const unsigned char *)"title", item->title);
        e_xml_set_string_prop_by_name(child, (const unsigned char *)"type", item->type);
    }
    filename = g_build_filename(collection->local_dir, "galview.xml", NULL);
    if (e_xml_save_file (filename, doc) == -1)
        g_warning ("Unable to save view to %s - %s", filename, g_strerror(errno));
    xmlFreeDoc(doc);
    g_free(filename);
}

/**
 * gal_view_collection_get_count
 * @collection: The view collection to count
 *
 * Calculates the number of views in the given collection.
 *
 * Returns: The number of views in the collection.
 */
gint
gal_view_collection_get_count (GalViewCollection *collection)
{
    g_return_val_if_fail (collection != NULL, -1);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), -1);

    return collection->view_count;
}

/**
 * gal_view_collection_get_view
 * @collection: The view collection to query
 * @n: The view to get.
 *
 * Returns: The nth view in the collection
 */
GalView *
gal_view_collection_get_view (GalViewCollection *collection,
                  int n)
{
    g_return_val_if_fail (collection != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), NULL);
    g_return_val_if_fail (n < collection->view_count, NULL);
    g_return_val_if_fail (n >= 0, NULL);

    return collection->view_data[n]->view;
}

/**
 * gal_view_collection_get_view_item
 * @collection: The view collection to query
 * @n: The view item to get.
 *
 * Returns: The nth view item in the collection
 */
GalViewCollectionItem *
gal_view_collection_get_view_item (GalViewCollection *collection,
                   int n)
{
    g_return_val_if_fail (collection != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), NULL);
    g_return_val_if_fail(n < collection->view_count, NULL);
    g_return_val_if_fail(n >= 0, NULL);

    return collection->view_data[n];
}

int
gal_view_collection_get_view_index_by_id     (GalViewCollection *collection, const char *view_id)
{
    int i;
    for (i = 0; i < collection->view_count; i++) {
        if (!strcmp (collection->view_data[i]->id, view_id))
            return i;
    }
    return -1;
}

char *
gal_view_collection_get_view_id_by_index (GalViewCollection *collection, int n)
{
    g_return_val_if_fail (collection != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), NULL);
    g_return_val_if_fail(n < collection->view_count, NULL);
    g_return_val_if_fail(n >= 0, NULL);

    return g_strdup (collection->view_data[n]->id);
}


void
gal_view_collection_append                   (GalViewCollection *collection,
                          GalView           *view)
{
    GalViewCollectionItem *item;

    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (view != NULL);
    g_return_if_fail (GAL_IS_VIEW (view));

    item = g_new(GalViewCollectionItem, 1);
    item->ever_changed = TRUE;
    item->changed = TRUE;
    item->built_in = FALSE;
    item->title = g_strdup(gal_view_get_title(view));
    item->type = g_strdup(gal_view_get_type_code(view));
    item->id = gal_view_generate_id(collection, view);
    item->filename = g_strdup_printf("%s.galview", item->id);
    item->view = view;
    item->collection = collection;
    g_object_ref(view);

    item->view_changed_id =
        g_signal_connect(item->view, "changed",
                 G_CALLBACK (view_changed), item);

    collection->view_data = g_renew(GalViewCollectionItem *, collection->view_data, collection->view_count + 1);
    collection->view_data[collection->view_count] = item;
    collection->view_count ++;

    gal_view_collection_changed(collection);
}

void
gal_view_collection_delete_view              (GalViewCollection *collection,
                          int                i)
{
    GalViewCollectionItem *item;

    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (i >= 0 && i < collection->view_count);

    item = collection->view_data[i];
    memmove(collection->view_data + i, collection->view_data + i + 1, (collection->view_count - i - 1) * sizeof(GalViewCollectionItem *));
    collection->view_count --;
    if (item->built_in) {
        g_free(item->filename);
        item->filename = NULL;

        collection->removed_view_data = g_renew(GalViewCollectionItem *, collection->removed_view_data, collection->removed_view_count + 1);
        collection->removed_view_data[collection->removed_view_count] = item;
        collection->removed_view_count ++;
    } else {
        gal_view_collection_item_free (item);
    }

    gal_view_collection_changed(collection);
}

void
gal_view_collection_copy_view                (GalViewCollection *collection,
                          int                i)
{
    GalViewCollectionItem *item;
    GalView *view;

    g_return_if_fail (collection != NULL);
    g_return_if_fail (GAL_IS_VIEW_COLLECTION (collection));
    g_return_if_fail (i >= 0 && i < collection->view_count);

    view = collection->view_data[i]->view;

    item = g_new(GalViewCollectionItem, 1);
    item->ever_changed = TRUE;
    item->changed = FALSE;
    item->built_in = FALSE;
    item->title = g_strdup(gal_view_get_title(view));
    item->type = g_strdup(gal_view_get_type_code(view));
    item->id = gal_view_generate_id(collection, view);
    item->filename = g_strdup_printf("%s.galview", item->id);
    item->view = gal_view_clone(view);
    item->collection = collection;

    item->view_changed_id =
        g_signal_connect(item->view, "changed",
                 G_CALLBACK (view_changed), item);

    collection->view_data = g_renew(GalViewCollectionItem *, collection->view_data, collection->view_count + 1);
    collection->view_data[collection->view_count] = item;
    collection->view_count ++;

    gal_view_collection_changed(collection);
}

gboolean
gal_view_collection_loaded (GalViewCollection *collection)
{
    return collection->loaded;
}

const char *
gal_view_collection_append_with_title (GalViewCollection *collection, const char *title, GalView *view)
{
    GalViewCollectionItem *item;

    g_return_val_if_fail (collection != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), NULL);
    g_return_val_if_fail (view != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW (view), NULL);

    gal_view_set_title (view, title);

    d(g_print("%s: %p\n", G_GNUC_FUNCTION, view));

    item = g_new(GalViewCollectionItem, 1);
    item->ever_changed = TRUE;
    item->changed = TRUE;
    item->built_in = FALSE;
    item->title = g_strdup(gal_view_get_title(view));
    item->type = g_strdup(gal_view_get_type_code(view));
    item->id = gal_view_generate_id(collection, view);
    item->filename = g_strdup_printf("%s.galview", item->id);
    item->view = view;
    item->collection = collection;
    g_object_ref(view);

    item->view_changed_id =
        g_signal_connect(item->view, "changed",
                 G_CALLBACK (view_changed), item);

    collection->view_data = g_renew(GalViewCollectionItem *, collection->view_data, collection->view_count + 1);
    collection->view_data[collection->view_count] = item;
    collection->view_count ++;

    gal_view_collection_changed(collection);
    return item->id;
}

const char *
gal_view_collection_set_nth_view (GalViewCollection *collection, int i, GalView *view)
{
    GalViewCollectionItem *item;

    g_return_val_if_fail (collection != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW_COLLECTION (collection), NULL);
    g_return_val_if_fail (view != NULL, NULL);
    g_return_val_if_fail (GAL_IS_VIEW (view), NULL);
    g_return_val_if_fail (i >= 0, NULL);
    g_return_val_if_fail (i < collection->view_count, NULL);

    d(g_print("%s: %p\n", G_GNUC_FUNCTION, view));

    item = collection->view_data[i];

    gal_view_set_title (view, item->title);
    g_object_ref (view);
    if (item->view) {
        g_signal_handler_disconnect (item->view,
                         item->view_changed_id);
        g_object_unref (item->view);
    }
    item->view = view;

    item->ever_changed = TRUE;
    item->changed = TRUE;
    item->type = g_strdup(gal_view_get_type_code(view));

    item->view_changed_id =
        g_signal_connect(item->view, "changed",
                 G_CALLBACK (view_changed), item);

    gal_view_collection_changed (collection);
    return item->id;
}

const char *
gal_view_collection_get_default_view (GalViewCollection *collection)
{
    return collection->default_view;
}

void
gal_view_collection_set_default_view (GalViewCollection *collection, const char *id)
{
    g_free (collection->default_view);
    collection->default_view = g_strdup (id);
    gal_view_collection_changed (collection);
    collection->default_view_built_in = FALSE;
}