camerabin

// -*- Mode: vala; indent-tabs-mode: nil; tab-width: 4 -*-
/***
  BEGIN LICENSE

  Copyright (C) 2011-2013 Mario Guerriero <mario@elementaryos.org>
  This program is free software: you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License version 3, as
  published    by the Free Software Foundation.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranties of
  MERCHANTABILITY, SATISFACTORY QUALITY, 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, see <http://www.gnu.org/licenses>

  END LICENSE
***/

namespace Snap.Widgets {

    public class Camera : Gtk.DrawingArea {

        private uint* xid;
        private Gst.Element? camerabin = null;

        public class Camera () {
            this.realize.connect (() => {
                this.get_window ().ensure_native ();
                xid = (uint*)Gdk.X11Window.get_xid (this.get_window ());
             });

            this.camerabin = Gst.ElementFactory.make ("camerabin", "camera");

            var bus = this.camerabin.get_bus ();
            bus.add_watch (Priority.DEFAULT, on_bus_watch);
            bus.set_sync_handler (on_bus_callback);

            var wrapper_src = Gst.ElementFactory.make ("wrappercamerabinsrc", null);
            camerabin.set ("camera-source", wrapper_src);

            var v4l2_src = Gst.ElementFactory.make ("v4l2src", null);
            wrapper_src.set ("video-source", v4l2_src);

            var gudev = new GUdev.Client ({ "video4linux", null });
            var devices = gudev.query_by_subsystem ("video4linux");
            var device_file = devices.data.get_device_file ();
            v4l2_src.set ("device", device_file);

            this.play ();
            this.show_all ();
        }

        private bool on_bus_watch (Gst.Bus bus, Gst.Message message) {
    if(Gst.Video.is_video_overlay_prepare_window_handle_message(message))
                (message.src as Gst.Video.Overlay).set_window_handle(xid);
            return true;
        }

        private Gst.BusSyncReply on_bus_callback (Gst.Bus bus, Gst.Message message) {
            if (message.type != Gst.MessageType.ELEMENT)
                return Gst.BusSyncReply.PASS;

            if (!message.has_name ("prepare-window-handle"))
                return Gst.BusSyncReply.PASS;

            var overlay = message.src as Gst.Video.Overlay;
            overlay.set_window_handle (Camera.xid);

            return Gst.BusSyncReply.DROP;
        }

        public void play () {
            this.camerabin.set_state (Gst.State.PLAYING);
        }

        public void stop () {
            this.camerabin.set_state (Gst.State.NULL);
        }
    }
}