// SPDX-FileCopyrightText: 2023 The wlroots contributors
// SPDX-FileCopyrightText: 2023 KylinSoft Co., Ltd.
//
// SPDX-License-Identifier: Expat

#include <stdlib.h>

#include "util/wayland.h"

/**
 * stolen from wlroots.
 */

struct destroy_global_data {
    struct wl_global *global;
    struct wl_event_source *event_source;
    struct wl_listener display_destroy;
};

static void destroy_global(struct destroy_global_data *data)
{
    wl_list_remove(&data->display_destroy.link);
    wl_global_destroy(data->global);
    wl_event_source_remove(data->event_source);
    free(data);
}

static int handle_timer_event(void *data)
{
    destroy_global(data);
    return 0;
}

static void handle_display_destroy(struct wl_listener *listener, void *_data)
{
    struct destroy_global_data *data = wl_container_of(listener, data, display_destroy);
    destroy_global(data);
}

void wl_global_destroy_safe(struct wl_global *global)
{
    // Don't destroy the global immediately. If the global has been created
    // recently, clients might try to bind to it after we've destroyed it.
    // Instead, remove the global so that clients stop seeing it and wait an
    // arbitrary amount of time before destroying the global as a workaround.
    // See: https://gitlab.freedesktop.org/wayland/wayland/issues/10

    wl_global_remove(global);
    wl_global_set_user_data(global, NULL); // safety net

    struct wl_display *display = wl_global_get_display(global);
    struct wl_event_loop *event_loop = wl_display_get_event_loop(display);
    struct destroy_global_data *data = calloc(1, sizeof(*data));
    if (data == NULL) {
        wl_global_destroy(global);
        return;
    }
    data->global = global;
    data->event_source = wl_event_loop_add_timer(event_loop, handle_timer_event, data);
    if (data->event_source == NULL) {
        free(data);
        wl_global_destroy(global);
        return;
    }
    wl_event_source_timer_update(data->event_source, 5000);

    data->display_destroy.notify = handle_display_destroy;
    wl_display_add_destroy_listener(display, &data->display_destroy);
}

void wl_signal_emit_oneshot(struct wl_signal *signal, void *data)
{
    struct wl_list *listeners = &signal->listener_list;
    if (wl_list_empty(listeners)) {
        return;
    }

    struct wl_listener *listener = wl_container_of(listeners->next, listener, link);
    listener->notify(listener, data);
}
