From f350da799a32cfeb90b72aff321260d354482ffe Mon Sep 17 00:00:00 2001
From: Pyro57000 <147988717+Pyro57000@users.noreply.github.com>
Date: Mon, 30 Dec 2024 14:43:18 -0600
Subject: [PATCH] add dbus screen cast python script

I found this on the immersed discord server (https://immersed.com/community) in the linux help channel, all credit for developing this script goes to augustoicaro in that community for making the script!

Link to message containing script: https://discord.com/channels/428916969283125268/681876093107699736/1265171421923901471
---
 HMD setup/dbus_screen_cast.py | 121 ++++++++++++++++++++++++++++++++++
 1 file changed, 121 insertions(+)
 create mode 100644 HMD setup/dbus_screen_cast.py

diff --git a/HMD setup/dbus_screen_cast.py b/HMD setup/dbus_screen_cast.py
new file mode 100644
index 0000000..1a13a95
--- /dev/null
+++ b/HMD setup/dbus_screen_cast.py	
@@ -0,0 +1,121 @@
+#!/usr/bin/python3
+
+import re
+import signal
+import dbus
+from gi.repository import GLib
+from dbus.mainloop.glib import DBusGMainLoop
+
+import gi
+gi.require_version('Gst', '1.0')
+from gi.repository import GObject, Gst
+
+DBusGMainLoop(set_as_default=True)
+Gst.init(None)
+
+loop = GLib.MainLoop()
+
+bus = dbus.SessionBus()
+request_iface = 'org.freedesktop.portal.Request'
+screen_cast_iface = 'org.freedesktop.portal.ScreenCast'
+
+pipeline = None
+
+def terminate():
+    if pipeline is not None:
+        self.player.set_state(Gst.State.NULL)
+    loop.quit()
+
+request_token_counter = 0
+session_token_counter = 0
+sender_name = re.sub(r'\.', r'_', bus.get_unique_name()[1:])
+
+def new_request_path():
+    global request_token_counter
+    request_token_counter = request_token_counter + 1
+    token = 'u%d'%request_token_counter
+    path = '/org/freedesktop/portal/desktop/request/%s/%s'%(sender_name, token)
+    return (path, token)
+
+def new_session_path():
+    global session_token_counter
+    session_token_counter = session_token_counter + 1
+    token = 'u%d'%session_token_counter
+    path = '/org/freedesktop/portal/desktop/session/%s/%s'%(sender_name, token)
+    return (path, token)
+
+def screen_cast_call(method, callback, *args, options={}):
+    (request_path, request_token) = new_request_path()
+    bus.add_signal_receiver(callback,
+                            'Response',
+                            request_iface,
+                            'org.freedesktop.portal.Desktop',
+                            request_path)
+    options['handle_token'] = request_token
+    method(*(args + (options, )),
+           dbus_interface=screen_cast_iface)
+
+def on_gst_message(bus, message):
+    type = message.type
+    if type == Gst.MessageType.EOS or type == Gst.MessageType.ERROR:
+        terminate()
+
+def play_pipewire_stream(node_id):
+    empty_dict = dbus.Dictionary(signature="sv")
+    fd_object = portal.OpenPipeWireRemote(session, empty_dict,
+                                          dbus_interface=screen_cast_iface)
+    fd = fd_object.take()
+    #pipeline = Gst.parse_launch('pipewiresrc fd=%d path=%u ! videoconvert ! xvimagesink'%(fd, node_id))
+    pipeline = Gst.parse_launch('pipewiresrc fd=%d path=%u ! videoconvert'%(fd, node_id))
+    pipeline.set_state(Gst.State.PLAYING)
+    pipeline.get_bus().connect('message', on_gst_message)
+
+def on_start_response(response, results):
+    if response != 0:
+        print("Failed to start: %s"%response)
+        terminate()
+        return
+
+    print("streams:")
+    for (node_id, stream_properties) in results['streams']:
+        print("stream {}".format(node_id))
+        play_pipewire_stream(node_id)
+
+def on_select_sources_response(response, results):
+    if response != 0:
+        print("Failed to select sources: %d"%response)
+        terminate()
+        return
+
+    print("sources selected")
+    global session
+    screen_cast_call(portal.Start, on_start_response,
+                     session, '')
+
+def on_create_session_response(response, results):
+    if response != 0:
+        print("Failed to create session: %d"%response)
+        terminate()
+        return
+
+    global session
+    session = results['session_handle']
+    print("session %s created"%session)
+
+    screen_cast_call(portal.SelectSources, on_select_sources_response,
+                     session,
+                     options={ 'multiple': False,
+                               'types': dbus.UInt32(1|2) })
+
+portal = bus.get_object('org.freedesktop.portal.Desktop',
+                             '/org/freedesktop/portal/desktop')
+
+(session_path, session_token) = new_session_path()
+screen_cast_call(portal.CreateSession, on_create_session_response,
+                 options={ 'session_handle_token': session_token })
+
+try:
+    loop.run()
+except KeyboardInterrupt:
+    terminate()
+