from components import (

	EmulationCore, GLRenderer, Laserdisc, iterComponents

	)

class Configuration(object):

	def __init__(self, requiredComponents, optionalComponents, linkStatic):

		self.__requiredComponents = requiredComponents

		self.__optionalComponents = optionalComponents

		self.__linkStatic = linkStatic

	def iterRequiredComponents(self):

		return iter(self.__requiredComponents)

	def iterOptionalComponents(self):

		return iter(self.__optionalComponents)

	def iterDesiredComponents(self):

		return iter(self.__requiredComponents | self.__optionalComponents)

	def iterBuildableComponents(self, probeVars):

		for component in self.iterDesiredComponents():

			if component.canBuild(probeVars):

				yield component

	def linkStatic(self):

		'''Returns True iff static linking should be used for non-system libs.

		'''

		return self.__linkStatic

def getConfiguration(name):

	if name == 'SYS_DYN':

		requiredComponents = set((EmulationCore, ))

		optionalComponents = set(iterComponents()) - requiredComponents

		linkStatic = False

	elif name == '3RD_STA':

		requiredComponents = set((EmulationCore, GLRenderer))

		optionalComponents = set(iterComponents()) - requiredComponents

		linkStatic = True

	elif name == '3RD_STA_GLES':

		# TODO: We don't have an OpenGL ES component yet.

		requiredComponents = set((EmulationCore, ))

		optionalComponents = \

			set(iterComponents()) - requiredComponents - set((GLRenderer, ))

		linkStatic = True

	elif name == '3RD_STA_MIN':

		requiredComponents = set((EmulationCore, ))

		optionalComponents = set()

		linkStatic = True

	else:

		raise ValueError('No configuration named "%s"' % name)

	return Configuration(requiredComponents, optionalComponents, linkStatic)