from enigma import eTimer
from Converter import Converter

class ConditionalShowHide(Converter, object):
	def __init__(self, argstr):
		Converter.__init__(self, argstr)
		args = argstr.split(',')
		self.invert = "Invert" in args
		self.blink = "Blink" in args
		if self.blink:
			self.blinktime = 500
			self.timer = eTimer()
			self.timer.callback.append(self.blinkFunc)
		else:
			self.timer = None

	def blinkFunc(self):
		if self.blinking == True:
			for x in self.downstream_elements:
				x.visible = not x.visible

	def startBlinking(self):
		self.blinking = True
		self.timer.start(self.blinktime)

	def stopBlinking(self):
		self.blinking = False
		for x in self.downstream_elements:
			if x.visible:
				x.hide()
		self.timer.stop()

	def calcVisibility(self):
		b = self.source.boolean
		if b is None:
			return True
		b ^= self.invert
		return b

	def changed(self, what):
		vis = self.calcVisibility()
		if self.blink:
			if vis:
				self.startBlinking()
			else:
				self.stopBlinking()
		else:
			for x in self.downstream_elements:
				x.visible = vis

	def connectDownstream(self, downstream):
		Converter.connectDownstream(self, downstream)
		vis = self.calcVisibility()
		if self.blink:
			if vis:
				self.startBlinking()
			else:
				self.stopBlinking()
		else:
			downstream.visible = self.calcVisibility()

	def destroy(self):
		if self.timer:
			self.timer.callback.remove(self.blinkFunc)