Merge c8fc7a4 into 33694a0

source/braille.py

@@ -19,6 +19,7 @@
 	Tuple,
 	Union,
 	Type,
+	Callable,
 )
 from locale import strxfrm
 
@@ -42,6 +43,7 @@
 	TetherTo,
 	ReportTableHeaders,
 )
+from config.featureFlag import FeatureFlag
 from config.featureFlagEnums import ReviewRoutingMovesSystemCaretFlag
 from logHandler import log
 import controlTypes
@@ -53,6 +55,7 @@
 import re
 import scriptHandler
 import collections
+from collections import deque
 import extensionPoints
 import hwPortUtils
 import bdDetect
@@ -1569,6 +1572,7 @@ def bufferPosToRegionPos(self, bufferPos):
 		raise LookupError("No such position")
 
 	def regionPosToBufferPos(self, region, pos, allowNearest=False):
+		start: int = 0
 		for testRegion, start, end in self.regionsWithPositions:
 			if region == testRegion:
 				if pos < end - start:
@@ -2003,6 +2007,44 @@ def formatCellsForLog(cells: List[int]) -> str:
 """
 
 
+class UpdateTimer:
+	"""Repeating timer for keeping display content always up to date."""
+
+	def __init__(
+			self,
+			interval: float,
+			updateFunction: Callable[[], None]
+	):
+		"""Constructor.
+		@param interval: Checking frequency
+		@param updateFunction: Update display
+		"""
+		self._interval = interval
+		self._timer = threading.Timer(self._interval, self._run)
+		self._updateFunction = updateFunction
+		self.is_running = False
+		self.start()
+
+	def _run(self):
+		self.is_running = False
+		self.start()
+		self._updateFunction()
+
+	def start(self):
+		if not self.is_running:
+			self._timer = threading.Timer(self._interval, self._run)
+			self._timer.start()
+			self.is_running = True
+
+	def stop(self):
+		self._timer.cancel()
+		self.is_running = False
+
+
+BRAILLE_UPDATE_CHECK_INTERVAL: float = 0.5
+"""Timer interval in milliseconds for L{BrailleHandler._enqueueBrailleUpdateCheck}."""
+
+
 class BrailleHandler(baseObject.AutoPropertyObject):
 	# TETHER_AUTO, TETHER_FOCUS, TETHER_REVIEW and tetherValues
 	# are deprecated, but remain to retain API backwards compatibility
@@ -2042,6 +2084,17 @@ def __init__(self):
 		self._cursorPos = None
 		self._cursorBlinkUp = True
 		self._cells = []
+		self._oldCells: List[int] = []
+		self._showSelection: FeatureFlag = config.conf["braille"]["showSelection"]
+		self._showCursor: bool = config.conf["braille"]["showCursor"]
+		# Was braille line updated during previous timer cycle.
+		self._alreadyUpdated: bool = False
+		self._handleUpdateQueue = deque(maxlen=1)
+		self._updateTimer = UpdateTimer(
+			BRAILLE_UPDATE_CHECK_INTERVAL,
+			self._enqueueBrailleUpdateCheck
+		)
+		self._updateTimer.start()
 		self._cursorBlinkTimer = None
 		config.post_configProfileSwitch.register(self.handlePostConfigProfileSwitch)
 		if config.conf["braille"]["tetherTo"] == TetherTo.AUTO.value:
@@ -2064,6 +2117,9 @@ def terminate(self):
 		if self._cursorBlinkTimer:
 			self._cursorBlinkTimer.Stop()
 			self._cursorBlinkTimer = None
+		if self._updateTimer:
+			self._updateTimer.stop()
+			self._updateTimer = None
 		config.post_configProfileSwitch.unregister(self.handlePostConfigProfileSwitch)
 		if self.display:
 			self.display.terminate()
@@ -2341,6 +2397,10 @@ def update(self):
 		self._cells = cells + [0] * (self.displaySize - len(cells))
 		self._cursorPos = self.buffer.cursorWindowPos
 		self._updateDisplay()
+		self._oldCells = self.buffer.windowBrailleCells.copy()
+		self._showSelection = config.conf["braille"]["showSelection"]
+		self._showCursor = config.conf["braille"]["showCursor"]
+		self._alreadyUpdated = True
 
 	def scrollForward(self):
 		self.buffer.scrollForward()
@@ -2468,6 +2528,12 @@ def handleCaretMove(
 		if shouldAutoTether:
 			self.setTether(TetherTo.FOCUS.value, auto=True)
 		if self._tether != TetherTo.FOCUS.value:
+			# Braille display content is updated in case where:
+			# braille is tethered to review, review cursor does not follow system caret,
+			# and focus object is navigator object.
+			if not config.conf["reviewCursor"]["followCaret"]:
+				if obj == api.getNavigatorObject():
+					self.handleUpdate(obj)
 			return
 		region = self.mainBuffer.regions[-1] if self.mainBuffer.regions else None
 		if region and region.obj==obj:
@@ -2552,6 +2618,8 @@ def handleUpdate(self, obj: "NVDAObject") -> None:
 		region.update()
 		self.mainBuffer.update()
 		self.mainBuffer.restoreWindow()
+		if self._oldCells == self.buffer.windowBrailleCells:
+			return
 		if self.buffer is self.mainBuffer:
 			self.update()
 		elif self.buffer is self.messageBuffer and keyboardHandler.keyCounter>self._keyCountForLastMessage:
@@ -2686,6 +2754,35 @@ def _ackTimeoutResetter(self, param: int):
 			self.display._awaitingAck = False
 			self._writeCellsInBackground()
 
+	def _brailleUpdateCheck(self) -> None:
+		"""Braille may need update when show cursor or show selection state change or when in terminal window."""
+		if self.buffer is not self.mainBuffer:
+			return
+		if self._alreadyUpdated:
+			self._alreadyUpdated = False
+			return
+		obj: NVDAObject
+		if api.isObjectInActiveTreeInterceptor(api.getNavigatorObject()):
+			obj = api.getCaretObject()
+		elif self.getTether() == TetherTo.FOCUS.value:
+			obj = api.getFocusObject()
+		else:
+			obj = api.getNavigatorObject()
+		# Handles updates in terminal windows, and also "show selection" state
+		# change in all appropriate windows.
+		if (
+			hasattr(obj, "role") and obj.role == controlTypes.Role.TERMINAL
+			or self._showSelection != config.conf["braille"]["showSelection"]
+		):
+			self.handleUpdate(obj)
+		# Toggles braille cursor in other appropriate windows.
+		if self._showCursor != config.conf["braille"]["showCursor"]:
+			self.update()
+
+	def _enqueueBrailleUpdateCheck(self) -> None:
+		"""Enques braille update check."""
+		self._handleUpdateQueue.append(self._brailleUpdateCheck)
+
 
 # Maps old braille display driver names to new drivers that supersede old drivers.
 # Ensure that if a user has set a preferred driver which has changed name, the new
@@ -2720,14 +2817,17 @@ def initialize():
 	handler.setDisplayByName(config.conf["braille"]["display"])
 
 def pumpAll():
-	"""Runs tasks at the end of each core cycle. For now just caret updates."""
+	"""Runs tasks at the end of each core cycle."""
+	if len(handler._handleUpdateQueue):
+		handler._handleUpdateQueue.popleft()()
 	handler.handlePendingCaretUpdate()
 
 def terminate():
 	global handler
 	handler.terminate()
 	handler = None
 
+
 class BrailleDisplayDriver(driverHandler.Driver):
 	"""Abstract base braille display driver.
 	Each braille display driver should be a separate Python module in the root brailleDisplayDrivers directory