Keystrokes to adjust applications volume and mute [take 2]

source/audio/__init__.py

@@ -8,9 +8,48 @@
 	_setSoundSplitState,
 	_toggleSoundSplitState,
 )
+from . import appsVolume, soundSplit, utils
+import atexit
+import nvwave
+from pycaw.utils import AudioUtilities
+from comtypes import COMError
+from logHandler import log
 
 __all__ = [
 	"SoundSplitState",
 	"_setSoundSplitState",
 	"_toggleSoundSplitState",
 ]
+
+audioUtilitiesInitialized: bool = False
+
+
+def initialize() -> None:
+	if nvwave.usingWasapiWavePlayer():
+		try:
+			AudioUtilities.GetAudioSessionManager()
+		except COMError:
+			log.exception("Could not initialize audio session manager")
+			return
+		log.debug("Initializing utils")
+		utils.initialize()
+		log.debug("Initializing appsVolume")
+		appsVolume.initialize()
+		log.debug("Initializing soundSplit")
+		soundSplit.initialize()
+		global audioUtilitiesInitialized
+		audioUtilitiesInitialized = True
+	else:
+		log.debug("Cannot initialize audio utilities as WASAPI is disabled")
+
+
+@atexit.register
+def terminate():
+	if not audioUtilitiesInitialized:
+		log.debug("Skipping terminating audio utilities as initialization was skipped.")
+	elif not nvwave.usingWasapiWavePlayer():
+		log.debug("Skipping terminating audio utilites as WASAPI is disabled.")
+	else:
+		soundSplit.terminate()
+		appsVolume.terminate()
+		utils.terminate()

source/audio/appsVolume.py

@@ -0,0 +1,160 @@
+# A part of NonVisual Desktop Access (NVDA)
+# Copyright (C) 2024 NV Access Limited
+# This file is covered by the GNU General Public License.
+# See the file COPYING for more details.
+
+import config
+import globalVars
+from logHandler import log
+import nvwave
+from pycaw.utils import AudioSession
+import ui
+from dataclasses import dataclass
+from threading import Lock
+from config.featureFlagEnums import AppsVolumeAdjusterFlag
+from typing import NamedTuple
+from .utils import AudioSessionCallback, DummyAudioSessionCallback
+
+
+class VolumeAndMute(NamedTuple):
+	volume: float
+	mute: bool
+
+
+_appVolumesCache: dict[int, VolumeAndMute] = {}
+_appVolumesCacheLock = Lock()
+_activeCallback: DummyAudioSessionCallback | None = None
+
+
+def initialize() -> None:
+	state = config.conf["audio"]["applicationsVolumeMode"]
+	if state == AppsVolumeAdjusterFlag.MUTED:
+		state = AppsVolumeAdjusterFlag.ENABLED
+		config.conf["audio"]["applicationsVolumeMode"] = state
+	volume = config.conf["audio"]["applicationsSoundVolume"]
+	_updateAppsVolumeImpl(volume / 100.0, state)
+
+
+def terminate():
+	global _activeCallback
+	if _activeCallback is not None:
+		_activeCallback.unregister()
+		_activeCallback = None
+
+
+@dataclass(unsafe_hash=True)
+class VolumeSetter(AudioSessionCallback):
+	volumeAndMute: VolumeAndMute | None = None
+
+	def getOriginalVolumeAndMute(self, pid: int) -> VolumeAndMute:
+		try:
+			with _appVolumesCacheLock:
+				originalVolumeAndMute = _appVolumesCache[pid]
+				del _appVolumesCache[pid]
+		except KeyError:
+			originalVolumeAndMute = VolumeAndMute(volume=1.0, mute=False)
+		return originalVolumeAndMute
+
+	def onSessionUpdate(self, session: AudioSession) -> None:
+		pid = session.ProcessId
+		simpleVolume = session.SimpleAudioVolume
+		with _appVolumesCacheLock:
+			if pid not in _appVolumesCache:
+				_appVolumesCache[pid] = VolumeAndMute(
+					volume=simpleVolume.GetMasterVolume(),
+					mute=simpleVolume.GetMute(),
+				)
+		if pid != globalVars.appPid:
+			simpleVolume.SetMasterVolume(self.volumeAndMute.volume, None)
+			simpleVolume.SetMute(self.volumeAndMute.mute, None)
+
+	def onSessionTerminated(self, session: AudioSession) -> None:
+		pid = session.ProcessId
+		simpleVolume = session.SimpleAudioVolume
+		originalVolumeAndMute = self.getOriginalVolumeAndMute(pid)
+		try:
+			simpleVolume.SetMasterVolume(originalVolumeAndMute.volume, None)
+			simpleVolume.SetMute(originalVolumeAndMute.mute, None)
+		except Exception:
+			log.exception(f"Could not restore master volume of process {pid} upon exit.")
+
+
+def _updateAppsVolumeImpl(
+		volume: float,
+		state: AppsVolumeAdjusterFlag,
+):
+	global _activeCallback
+	if state == AppsVolumeAdjusterFlag.DISABLED:
+		newCallback = DummyAudioSessionCallback()
+		runTerminators = True
+	else:
+		newCallback = VolumeSetter(
+			volumeAndMute=VolumeAndMute(
+				volume=volume,
+				mute=state == AppsVolumeAdjusterFlag.MUTED,
+			)
+		)
+		runTerminators = False
+	if _activeCallback is not None:
+		_activeCallback.unregister(runTerminators=runTerminators)
+	_activeCallback = newCallback
+	_activeCallback.register()
+
+
+def _adjustAppsVolume(
+		volumeAdjustment: int | None = None,
+):
+	if not nvwave.usingWasapiWavePlayer():
+		message = _(
+			# Translators: error message when wasapi is turned off.
+			"Other applications' volume cannot be adjusted. "
+			"Please enable WASAPI in the Advanced category in NVDA Settings to use it."
+		)
+		ui.message(message)
+		return
+	volume: int = config.conf["audio"]["applicationsSoundVolume"]
+	state = config.conf["audio"]["applicationsVolumeMode"]
+	if state != AppsVolumeAdjusterFlag.ENABLED:
+		# Translators: error message when applications' volume is disabled
+		msg = _("Please enable applications' volume adjuster in order to adjust applications' volume")
+		ui.message(msg)
+		return
+	volume += volumeAdjustment
+	volume = max(0, min(100, volume))
+	log.debug(f"Adjusting applications volume by {volumeAdjustment}% to {volume}%")
+	config.conf["audio"]["applicationsSoundVolume"] = volume
+
+	# We skip running terminators here to avoid application volume spiking to 100% for a split second.
+	_updateAppsVolumeImpl(volume / 100.0, state)
+	# Translators: Announcing new applications' volume message
+	msg = _("Applications volume {}").format(volume)
+	ui.message(msg)
+
+
+_APPS_VOLUME_STATES_ORDER = [
+	AppsVolumeAdjusterFlag.DISABLED,
+	AppsVolumeAdjusterFlag.ENABLED,
+	AppsVolumeAdjusterFlag.MUTED,
+]
+
+
+def _toggleAppsVolumeState():
+	if not nvwave.usingWasapiWavePlayer():
+		message = _(
+			# Translators: error message when wasapi is turned off.
+			"Other applications' volume cannot be adjusted. "
+			"Please enable WASAPI in the Advanced category in NVDA Settings to use it."
+		)
+		ui.message(message)
+		return
+	state = config.conf["audio"]["applicationsVolumeMode"]
+	volume: int = config.conf["audio"]["applicationsSoundVolume"]
+	try:
+		index = _APPS_VOLUME_STATES_ORDER.index(state)
+	except ValueError:
+		index = -1
+	index = (index + 1) % len(_APPS_VOLUME_STATES_ORDER)
+	state = _APPS_VOLUME_STATES_ORDER[index]
+	config.conf["audio"]["applicationsVolumeMode"] = state.name
+	_updateAppsVolumeImpl(volume / 100.0, state)
+	ui.message(state.displayString)