Add 'Refresh' popup menu item (part of geany-plugins #2999858).

[geany-mirror.git] / src / stash.c

/*
 *      stash.c - this file is part of Geany, a fast and lightweight IDE
 *
 *      Copyright 2008-2010 Nick Treleaven <nick(dot)treleaven(at)btinternet(dot)com>
 *      Copyright 2008-2010 Enrico Tröger <enrico(dot)troeger(at)uvena(dot)de>
 *
 *      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., 51 Franklin Street, Fifth Floor, Boston,
 *      MA 02110-1301, USA.
 *
 * $Id$
 */

/**
 * @file stash.h
 * Lightweight library for reading/writing @c GKeyFile settings and synchronizing widgets with
 * C variables.
 *
 * Note: Stash should only depend on GLib and GTK, but currently has some minor
 * dependencies on Geany's utils.c.
 *
 * @section Terms
 * 'Setting' is used only for data stored on disk or in memory.
 * 'Pref' can also include visual widget information.
 *
 * @section Memory Usage
 * Stash will not duplicate strings if they are normally static arrays, such as
 * keyfile group names and key names, string default values, widget_id names, property names.
 *
 * @section String Settings
 * String settings and other dynamically allocated settings will be initialized to NULL when
 * added to a StashGroup (so they can safely be reassigned later).
 *
 * @section Widget Support
 * Widgets very commonly used in configuration dialogs will be supported with their own function.
 * Widgets less commonly used such as @c GtkExpander or widget settings that aren't commonly needed
 * to be persistent won't be directly supported, to keep the library lightweight. However, you can
 * use stash_group_add_widget_property() to also save these settings for any read/write widget
 * property. Macros could be added for common widget properties such as @c GtkExpander:"expanded".
 *
 * @section settings-example Settings Example
 * @include stash-example.c
 * @note You might want to handle the warning/error conditions differently from above.
 *
 * @section prefs-example GUI Prefs Example
 * For prefs, it's the same as the above example but you add widget prefs instead of e.g.
 * boolean settings.
 *
 * This example uses lookup strings for widgets as they are more flexible than widget pointers.
 * @code
gboolean want_handle;
GtkWidget *parent;
GtkWidget *my_check_button;

stash_group_add_toggle_button(group, &want_handle, "handle", TRUE, "check_handle");
...
gtk_container_add(GTK_CONTAINER(parent), my_check_button);
ui_hookup_widget(parent, my_check_button, "check_handle");
...
stash_group_display(group, parent);
* @endcode
* Now let the user manipulate widgets. To synchronize the Stash settings afterwards, call:
* @code
stash_group_update(group, parent);
 * @endcode
 */

/* Implementation Note
 * We use a GArray to hold prefs. It would be more efficient for user code to declare
 * a static array of StashPref structs, but we don't do this because:
 *
 * * It would be more ugly (lots of casts and NULLs).
 * * Less type checking.
 * * The API would have to break when adding/changing fields.
 *
 * Usually the prefs code isn't what user code will spend most of its time doing, so this
 * should be efficient enough. But, if desired we could add a stash_group_set_size() function
 * to reduce reallocation.
 *
 * TODO: Maybe using GSlice chunks with an extra 'next' pointer would be more (memory) efficient.
 */


#include <gtk/gtk.h>

#include "stash.h"
#include "utils.h"              /* only for foreach_*, utils_get_setting_*(). Stash should not depend on Geany. */


struct StashPref
{
        GType setting_type;                     /* e.g. G_TYPE_INT */
        gpointer setting;
        const gchar *key_name;
        gpointer default_value;
        GType widget_type;                      /* e.g. GTK_TYPE_TOGGLE_BUTTON */
        StashWidgetID widget_id;        /* (GtkWidget*) or (gchar*) */
        gpointer fields;                        /* extra fields */
};

typedef struct StashPref StashPref;

struct StashGroup
{
        const gchar *name;                      /* group name to use in the keyfile */
        GArray *entries;                        /* array of StashPref */
        gboolean write_once;            /* only write settings if they don't already exist */
        gboolean use_defaults;          /* use default values if there's no keyfile entry */
};

typedef struct EnumWidget
{
        StashWidgetID widget_id;
        gint enum_id;
}
EnumWidget;


typedef enum SettingAction
{
        SETTING_READ,
        SETTING_WRITE
}
SettingAction;

typedef enum PrefAction
{
        PREF_DISPLAY,
        PREF_UPDATE
}
PrefAction;


static void handle_boolean_setting(StashGroup *group, StashPref *se,
                GKeyFile *config, SettingAction action)
{
        gboolean *setting = se->setting;

        switch (action)
        {
                case SETTING_READ:
                        *setting = utils_get_setting_boolean(config, group->name, se->key_name,
                                GPOINTER_TO_INT(se->default_value));
                        break;
                case SETTING_WRITE:
                        g_key_file_set_boolean(config, group->name, se->key_name, *setting);
                        break;
        }
}


static void handle_integer_setting(StashGroup *group, StashPref *se,
                GKeyFile *config, SettingAction action)
{
        gboolean *setting = se->setting;

        switch (action)
        {
                case SETTING_READ:
                        *setting = utils_get_setting_integer(config, group->name, se->key_name,
                                GPOINTER_TO_INT(se->default_value));
                        break;
                case SETTING_WRITE:
                        g_key_file_set_integer(config, group->name, se->key_name, *setting);
                        break;
        }
}


static void handle_string_setting(StashGroup *group, StashPref *se,
                GKeyFile *config, SettingAction action)
{
        gchararray *setting = se->setting;

        switch (action)
        {
                case SETTING_READ:
                        g_free(*setting);
                        *setting = utils_get_setting_string(config, group->name, se->key_name,
                                se->default_value);
                        break;
                case SETTING_WRITE:
                        g_key_file_set_string(config, group->name, se->key_name,
                                *setting ? *setting : "");
                        break;
        }
}


static void handle_strv_setting(StashGroup *group, StashPref *se,
                GKeyFile *config, SettingAction action)
{
        gchararray **setting = se->setting;

        switch (action)
        {
                case SETTING_READ:
                        g_strfreev(*setting);
                        *setting = g_key_file_get_string_list(config, group->name, se->key_name,
                                NULL, NULL);
                        if (*setting == NULL)
                                *setting = g_strdupv(se->default_value);
                        break;

                case SETTING_WRITE:
                {
                        /* don't try to save a NULL string vector */
                        gchar *dummy[] = { "", NULL };
                        gchar **strv = *setting ? *setting : dummy;

                        g_key_file_set_string_list(config, group->name, se->key_name,
                                (const gchar**)strv, g_strv_length(strv));
                        break;
                }
        }
}


static void keyfile_action(SettingAction action, StashGroup *group, GKeyFile *keyfile)
{
        StashPref *entry;

        foreach_array(StashPref, entry, group->entries)
        {
                /* don't overwrite write_once prefs */
                if (group->write_once && action == SETTING_WRITE &&
                        g_key_file_has_key(keyfile, group->name, entry->key_name, NULL))
                        continue;
                /* don't override settings with default values */
                if (!group->use_defaults && action == SETTING_READ &&
                        !g_key_file_has_key(keyfile, group->name, entry->key_name, NULL))
                        continue;

                switch (entry->setting_type)
                {
                        case G_TYPE_BOOLEAN:
                                handle_boolean_setting(group, entry, keyfile, action); break;
                        case G_TYPE_INT:
                                handle_integer_setting(group, entry, keyfile, action); break;
                        case G_TYPE_STRING:
                                handle_string_setting(group, entry, keyfile, action); break;
                        default:
                                /* G_TYPE_STRV is not a constant */
                                if (entry->setting_type == G_TYPE_STRV)
                                        handle_strv_setting(group, entry, keyfile, action);
                                else
                                        g_warning("Unhandled type for %s::%s in %s()!", group->name, entry->key_name,
                                                G_STRFUNC);
                }
        }
}


/** Reads key values from @a keyfile into the group settings.
 * @note You should still call this even if the keyfile couldn't be loaded from disk
 * so that all Stash settings are initialized to defaults.
 * @param group .
 * @param keyfile Usually loaded from a configuration file first. */
void stash_group_load_from_key_file(StashGroup *group, GKeyFile *keyfile)
{
        keyfile_action(SETTING_READ, group, keyfile);
}


/** Writes group settings into key values in @a keyfile.
 * @a keyfile is usually written to a configuration file afterwards.
 * @param group .
 * @param keyfile . */
void stash_group_save_to_key_file(StashGroup *group, GKeyFile *keyfile)
{
        keyfile_action(SETTING_WRITE, group, keyfile);
}


/** Reads group settings from a configuration file using @c GKeyFile.
 * @note Stash settings will be initialized to defaults if the keyfile
 * couldn't be loaded from disk.
 * @param group .
 * @param filename Filename of the file to read, in locale encoding.
 * @return @c TRUE if a key file could be loaded.
 * @see stash_group_load_from_key_file().
 **/
gboolean stash_group_load_from_file(StashGroup *group, const gchar *filename)
{
        GKeyFile *keyfile;
        gboolean ret;

        keyfile = g_key_file_new();
        ret = g_key_file_load_from_file(keyfile, filename, 0, NULL);
        /* even on failure we load settings to apply defaults */
        stash_group_load_from_key_file(group, keyfile);

        g_key_file_free(keyfile);
        return ret;
}


/** Writes group settings to a configuration file using @c GKeyFile.
 *
 * @param group .
 * @param filename Filename of the file to write, in locale encoding.
 * @param flags Keyfile options - @c G_KEY_FILE_NONE is the most efficient.
 * @return 0 if the file was successfully written, otherwise the @c errno of the
 *         failed operation is returned.
 * @see stash_group_save_to_key_file().
 **/
gint stash_group_save_to_file(StashGroup *group, const gchar *filename,
                GKeyFileFlags flags)
{
        GKeyFile *keyfile;
        gchar *data;
        gint ret;

        keyfile = g_key_file_new();
        /* if we need to keep comments or translations, try to load first */
        if (flags)
                g_key_file_load_from_file(keyfile, filename, flags, NULL);

        stash_group_save_to_key_file(group, keyfile);
        data = g_key_file_to_data(keyfile, NULL, NULL);
        ret = utils_write_file(filename, data);
        g_free(data);
        g_key_file_free(keyfile);
        return ret;
}


/** Creates a new group.
 * @param name Name used for @c GKeyFile group.
 * @return Group. */
StashGroup *stash_group_new(const gchar *name)
{
        StashGroup *group = g_new0(StashGroup, 1);

        group->name = name;
        group->entries = g_array_new(FALSE, FALSE, sizeof(StashPref));
        group->use_defaults = TRUE;
        return group;
}


/** Frees a group.
 * @param group . */
void stash_group_free(StashGroup *group)
{
        StashPref *entry;

        foreach_array(StashPref, entry, group->entries)
        {
                if (entry->widget_type == GTK_TYPE_RADIO_BUTTON)
                        g_free(entry->fields);
                else if (entry->widget_type == G_TYPE_PARAM)
                        continue;
                else
                        g_assert(entry->fields == NULL);        /* to prevent memory leaks, must handle fields above */
        }
        g_array_free(group->entries, TRUE);
        g_free(group);
}


/* Useful so the user can edit the keyfile manually while the program is running,
 * and the setting won't be overridden.
 * @c FALSE by default. */
void stash_group_set_write_once(StashGroup *group, gboolean write_once)
{
        group->write_once = write_once;
}


/* When @c FALSE, Stash doesn't change the setting if there is no keyfile entry, so it
 * remains whatever it was initialized/set to by user code.
 * @c TRUE by default. */
void stash_group_set_use_defaults(StashGroup *group, gboolean use_defaults)
{
        group->use_defaults = use_defaults;
}


static StashPref *
add_pref(StashGroup *group, GType type, gpointer setting,
                const gchar *key_name, gpointer default_value)
{
        StashPref entry = {type, setting, key_name, default_value, G_TYPE_NONE, NULL, NULL};
        GArray *array = group->entries;

        /* init any pointer settings to NULL so they can be freed later */
        if (type == G_TYPE_STRING ||
                type == G_TYPE_STRV)
                if (group->use_defaults)
                        *(gpointer**)setting = NULL;

        g_array_append_val(array, entry);

        return &g_array_index(array, StashPref, array->len - 1);
}


/** Adds boolean setting.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading. */
void stash_group_add_boolean(StashGroup *group, gboolean *setting,
                const gchar *key_name, gboolean default_value)
{
        add_pref(group, G_TYPE_BOOLEAN, setting, key_name, GINT_TO_POINTER(default_value));
}


/** Adds integer setting.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading. */
void stash_group_add_integer(StashGroup *group, gint *setting,
                const gchar *key_name, gint default_value)
{
        add_pref(group, G_TYPE_INT, setting, key_name, GINT_TO_POINTER(default_value));
}


/** Adds string setting.
 * The contents of @a setting will be initialized to @c NULL.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value String to copy if the key doesn't exist when loading, or @c NULL. */
void stash_group_add_string(StashGroup *group, gchar **setting,
                const gchar *key_name, const gchar *default_value)
{
        add_pref(group, G_TYPE_STRING, setting, key_name, (gpointer)default_value);
}


/** Adds string vector setting (array of strings).
 * The contents of @a setting will be initialized to @c NULL.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Vector to copy if the key doesn't exist when loading. Usually @c NULL. */
void stash_group_add_string_vector(StashGroup *group, gchar ***setting,
                const gchar *key_name, const gchar **default_value)
{
        add_pref(group, G_TYPE_STRV, setting, key_name, (gpointer)default_value);
}


/* *** GTK-related functions *** */

static void handle_toggle_button(GtkWidget *widget, gboolean *setting,
                PrefAction action)
{
        switch (action)
        {
                case PREF_DISPLAY:
                        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(widget), *setting);
                        break;
                case PREF_UPDATE:
                        *setting = gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(widget));
                        break;
        }
}


static void handle_spin_button(GtkWidget *widget, StashPref *entry,
                PrefAction action)
{
        gint *setting = entry->setting;

        g_assert(entry->setting_type == G_TYPE_INT);    /* only int spin prefs */

        switch (action)
        {
                case PREF_DISPLAY:
                        gtk_spin_button_set_value(GTK_SPIN_BUTTON(widget), *setting);
                        break;
                case PREF_UPDATE:
                        /* if the widget is focussed, the value might not be updated */
                        gtk_spin_button_update(GTK_SPIN_BUTTON(widget));
                        *setting = gtk_spin_button_get_value_as_int(GTK_SPIN_BUTTON(widget));
                        break;
        }
}


static void handle_combo_box(GtkWidget *widget, StashPref *entry,
                PrefAction action)
{
        gint *setting = entry->setting;

        switch (action)
        {
                case PREF_DISPLAY:
                        gtk_combo_box_set_active(GTK_COMBO_BOX(widget), *setting);
                        break;
                case PREF_UPDATE:
                        *setting = gtk_combo_box_get_active(GTK_COMBO_BOX(widget));
                        break;
        }
}


static void handle_entry(GtkWidget *widget, StashPref *entry,
                PrefAction action)
{
        gchararray *setting = entry->setting;

        switch (action)
        {
                case PREF_DISPLAY:
                        gtk_entry_set_text(GTK_ENTRY(widget), *setting);
                        break;
                case PREF_UPDATE:
                        g_free(*setting);
                        *setting = g_strdup(gtk_entry_get_text(GTK_ENTRY(widget)));
                        break;
        }
}


static void handle_combo_box_entry(GtkWidget *widget, StashPref *entry,
                PrefAction action)
{
        widget = gtk_bin_get_child(GTK_BIN(widget));
        handle_entry(widget, entry, action);
}


/* taken from Glade 2.x generated support.c */
static GtkWidget*
lookup_widget(GtkWidget *widget, const gchar *widget_name)
{
        GtkWidget *parent, *found_widget;

        for (;;)
                {
                        if (GTK_IS_MENU (widget))
                                parent = gtk_menu_get_attach_widget (GTK_MENU (widget));
                        else
                                parent = widget->parent;
                        if (!parent)
                                parent = (GtkWidget*) g_object_get_data (G_OBJECT (widget), "GladeParentKey");
                        if (parent == NULL)
                                break;
                        widget = parent;
                }

        found_widget = (GtkWidget*) g_object_get_data (G_OBJECT (widget), widget_name);
        if (!found_widget)
                g_warning ("Widget not found: %s", widget_name);
        return found_widget;
}


static GtkWidget *
get_widget(GtkWidget *owner, StashWidgetID widget_id)
{
        GtkWidget *widget = widget_id;

        if (owner)
        {
                const gchar *widget_name = widget_id;

                widget = lookup_widget(owner, widget_name);
        }
        if (!GTK_IS_WIDGET(widget))
        {
                g_warning("Unknown widget in %s()!", G_STRFUNC);
                return NULL;
        }
        return widget;
}


static void handle_radio_button(GtkWidget *widget, gint enum_id, gboolean *setting,
                PrefAction action)
{
        switch (action)
        {
                case PREF_DISPLAY:
                        if (*setting == enum_id)
                                gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(widget), TRUE);
                        break;
                case PREF_UPDATE:
                        if (gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(widget)))
                                *setting = enum_id;
                        break;
        }
}


static void handle_radio_buttons(GtkWidget *owner, EnumWidget *fields,
                gboolean *setting,
                PrefAction action)
{
        EnumWidget *field = fields;
        gsize count = 0;
        GtkWidget *widget = NULL;

        while (1)
        {
                widget = get_widget(owner, field->widget_id);

                if (!widget)
                        continue;

                count++;
                handle_radio_button(widget, field->enum_id, setting, action);
                field++;
                if (!field->widget_id)
                        break;
        }
        if (g_slist_length(gtk_radio_button_get_group(GTK_RADIO_BUTTON(widget))) != count)
                g_warning("Missing/invalid radio button widget IDs found!");
}


static void handle_widget_property(GtkWidget *widget, StashPref *entry,
                PrefAction action)
{
        GObject *object = G_OBJECT(widget);
        const gchar *name = entry->fields;

        switch (action)
        {
                case PREF_DISPLAY:
                        g_object_set(object, name, entry->setting, NULL);
                        break;
                case PREF_UPDATE:
                        if (entry->setting_type == G_TYPE_STRING)
                                g_free(entry->setting);
                        /* TODO: Which other types need freeing here? */

                        g_object_get(object, name, entry->setting, NULL);
                        break;
        }
}


static void pref_action(PrefAction action, StashGroup *group, GtkWidget *owner)
{
        StashPref *entry;

        foreach_array(StashPref, entry, group->entries)
        {
                GtkWidget *widget;

                /* ignore settings with no widgets */
                if (entry->widget_type == G_TYPE_NONE)
                        continue;

                /* radio buttons have several widgets */
                if (entry->widget_type == GTK_TYPE_RADIO_BUTTON)
                {
                        handle_radio_buttons(owner, entry->fields, entry->setting, action);
                        continue;
                }

                widget = get_widget(owner, entry->widget_id);
                if (!widget)
                {
                        g_warning("Unknown widget for %s::%s in %s()!", group->name, entry->key_name,
                                G_STRFUNC);
                        continue;
                }

                /* note: can't use switch for GTK_TYPE macros */
                if (entry->widget_type == GTK_TYPE_TOGGLE_BUTTON)
                        handle_toggle_button(widget, entry->setting, action);
                else if (entry->widget_type == GTK_TYPE_SPIN_BUTTON)
                        handle_spin_button(widget, entry, action);
                else if (entry->widget_type == GTK_TYPE_COMBO_BOX)
                        handle_combo_box(widget, entry, action);
                else if (entry->widget_type == GTK_TYPE_COMBO_BOX_ENTRY)
                        handle_combo_box_entry(widget, entry, action);
                else if (entry->widget_type == GTK_TYPE_ENTRY)
                        handle_entry(widget, entry, action);
                else if (entry->widget_type == G_TYPE_PARAM)
                        handle_widget_property(widget, entry, action);
                else
                        g_warning("Unhandled type for %s::%s in %s()!", group->name, entry->key_name,
                                G_STRFUNC);
        }
}


/** Applies Stash settings to widgets, usually called before displaying the widgets.
 * The @a owner argument depends on which type you use for @ref StashWidgetID.
 * @param group .
 * @param owner If non-NULL, used to lookup widgets by name, otherwise
 * widget pointers are assumed.
 * @see stash_group_update(). */
void stash_group_display(StashGroup *group, GtkWidget *owner)
{
        pref_action(PREF_DISPLAY, group, owner);
}


/** Applies widget values to Stash settings, usually called after displaying the widgets.
 * The @a owner argument depends on which type you use for @ref StashWidgetID.
 * @param group .
 * @param owner If non-NULL, used to lookup widgets by name, otherwise
 * widget pointers are assumed.
 * @see stash_group_display(). */
void stash_group_update(StashGroup *group, GtkWidget *owner)
{
        pref_action(PREF_UPDATE, group, owner);
}


static StashPref *
add_widget_pref(StashGroup *group, GType setting_type, gpointer setting,
                const gchar *key_name, gpointer default_value,
                GType widget_type, StashWidgetID widget_id)
{
        StashPref *entry =
                add_pref(group, setting_type, setting, key_name, default_value);

        entry->widget_type = widget_type;
        entry->widget_id = widget_id;
        return entry;
}


/** Adds a @c GtkToggleButton (or @c GtkCheckButton) widget pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later.
 * @see stash_group_add_radio_buttons(). */
void stash_group_add_toggle_button(StashGroup *group, gboolean *setting,
                const gchar *key_name, gboolean default_value, StashWidgetID widget_id)
{
        add_widget_pref(group, G_TYPE_BOOLEAN, setting, key_name, GINT_TO_POINTER(default_value),
                GTK_TYPE_TOGGLE_BUTTON, widget_id);
}


/** Adds a @c GtkRadioButton widget group pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later.
 * @param enum_id Enum value for @a widget_id.
 * @param ... pairs of @a widget_id, @a enum_id.
 * Example (using widget lookup strings, but widget pointers can also work):
 * @code
 * enum {FOO, BAR};
 * stash_group_add_radio_buttons(group, &which_one_setting, "which_one", BAR,
 *      "radio_foo", FOO, "radio_bar", BAR, NULL);
 * @endcode */
void stash_group_add_radio_buttons(StashGroup *group, gint *setting,
                const gchar *key_name, gint default_value,
                StashWidgetID widget_id, gint enum_id, ...)
{
        StashPref *entry =
                add_widget_pref(group, G_TYPE_INT, setting, key_name, GINT_TO_POINTER(default_value),
                        GTK_TYPE_RADIO_BUTTON, NULL);
        va_list args;
        gsize count = 1;
        EnumWidget *item, *array;

        /* count pairs of args */
        va_start(args, enum_id);
        while (1)
        {
                gint dummy;

                if (!va_arg(args, gpointer))
                        break;
                dummy = va_arg(args, gint);
                count++;
        }
        va_end(args);

        array = g_new0(EnumWidget, count + 1);
        entry->fields = array;

        va_start(args, enum_id);
        foreach_c_array(item, array, count)
        {
                if (item == array)
                {
                        /* first element */
                        item->widget_id = widget_id;
                        item->enum_id = enum_id;
                }
                else
                {
                        item->widget_id = va_arg(args, gpointer);
                        item->enum_id = va_arg(args, gint);
                }
        }
        va_end(args);
}


/** Adds a @c GtkSpinButton widget pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later. */
void stash_group_add_spin_button_integer(StashGroup *group, gint *setting,
                const gchar *key_name, gint default_value, StashWidgetID widget_id)
{
        add_widget_pref(group, G_TYPE_INT, setting, key_name, GINT_TO_POINTER(default_value),
                GTK_TYPE_SPIN_BUTTON, widget_id);
}


/** Adds a @c GtkComboBox widget pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later.
 * @see stash_group_add_combo_box_entry(). */
void stash_group_add_combo_box(StashGroup *group, gint *setting,
                const gchar *key_name, gint default_value, StashWidgetID widget_id)
{
        add_widget_pref(group, G_TYPE_INT, setting, key_name, GINT_TO_POINTER(default_value),
                GTK_TYPE_COMBO_BOX, widget_id);
}


/** Adds a @c GtkComboBoxEntry widget pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later. */
/* We could maybe also have something like stash_group_add_combo_box_entry_with_menu()
 * for the history list - or should that be stored as a separate setting? */
void stash_group_add_combo_box_entry(StashGroup *group, gchar **setting,
                const gchar *key_name, const gchar *default_value, StashWidgetID widget_id)
{
        add_widget_pref(group, G_TYPE_STRING, setting, key_name, (gpointer)default_value,
                GTK_TYPE_COMBO_BOX_ENTRY, widget_id);
}


/** Adds a @c GtkEntry widget pref.
 * @param group .
 * @param setting Address of setting variable.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * @param widget_id @c GtkWidget pointer or string to lookup widget later. */
void stash_group_add_entry(StashGroup *group, gchar **setting,
                const gchar *key_name, const gchar *default_value, StashWidgetID widget_id)
{
        add_widget_pref(group, G_TYPE_STRING, setting, key_name, (gpointer)default_value,
                GTK_TYPE_ENTRY, widget_id);
}


static GType object_get_property_type(GObject *object, const gchar *property_name)
{
        GObjectClass *klass = G_OBJECT_GET_CLASS(object);
        GParamSpec *ps;

        ps = g_object_class_find_property(klass, property_name);
        return ps->value_type;
}


/** Adds a widget's read/write property to the stash group.
 * The property will be set when calling
 * stash_group_display(), and read when calling stash_group_update().
 * @param group .
 * @param setting Address of e.g. an integer if using an integer property.
 * @param key_name Name for key in a @c GKeyFile.
 * @param default_value Value to use if the key doesn't exist when loading.
 * Should be cast into a pointer e.g. with @c GINT_TO_POINTER().
 * @param widget_id @c GtkWidget pointer or string to lookup widget later.
 * @param property_name .
 * @param type can be @c 0 if passing a @c GtkWidget as the @a widget_id argument to look it up from the
 * @c GObject data.
 * @warning Currently only string GValue properties will be freed before setting; patch for
 * other types - see @c handle_widget_property(). */
void stash_group_add_widget_property(StashGroup *group, gpointer setting,
                const gchar *key_name, gpointer default_value, StashWidgetID widget_id,
                const gchar *property_name, GType type)
{
        if (!type)
                type = object_get_property_type(G_OBJECT(widget_id), property_name);

        add_widget_pref(group, type, setting, key_name, default_value,
                G_TYPE_PARAM, widget_id)->fields = (gchar*)property_name;
}