import hashlib
from datetime import datetime

class RED_FAM:
	
	# Define the timestamp format
	__timestamp_format = "%H:%M,  %d. %b. %Y (%Z)"
	
	def __init__( self, articlesList, beginning=None, ending=None, status=0 ):
		"""
		Generates a new RED_FAM object
		
		@param		articlesList	list		List of articles of redundance family
		@param		beginning		datetime	Beginning date of redundance diskussion
		@param		ending			datetime	Ending date of redundance diskussion
		"""
		
		self.__articlesList = articlesList
		
		self.__hash = self.__get_fam_hash( )
		
		if( beginning ):
			self.add_beginning( beginning )
		else:
			self.__beginning = None
		
		if( ending ):
			self.add_ending( ending )
		else:
			self.__ending = None
			
		self.__status = status # __TODO__ STATUS CODE
		
	def __get_fam_hash( self ):
		"""
		Calculates the SHA-1 hash for the articlesList of redundance family.
		Since we don't need security SHA-1 is just fine.
		
		@returns	str					String with the hexadecimal hash digest
		"""
		
		h = hashlib.sha1()
		h.update( str( self.__articlesList ).encode('utf-8') )
		
		return h.hexdigest()
	
	def add_beginning( self, beginning ):
		"""
		Adds the beginning date of a redundance diskussion to the object and sets changed to True
		
		@param		datetime	datetime	Beginning date of redundance diskussion
		"""
		
		self.__beginning = self.__datetime( beginning )
		
		self.__changed = True
		
	def add_ending( self, ending ):
		"""
		Adds the ending date of a redundance diskussion to the object. Also sets the status to __TODO__ STATUS NUMBER and changed to True
		
		@param		datetime	datetime	Ending date of redundance diskussion
		"""
		
		self.__ending = self.__datetime( ending )
		
		self.__status = 2 #__TODO__ STATUS NUMBER
		self.__changed = True

	def __datetime( self, timestamp ):
		"""
		Decides wether given timestamp is a parseable string or a datetime object and returns a datetime object in both cases
		
		@param		timestamp	datetime	Datetime object
								str			Parseable string with timestamp in format __timestamp_format
								
		@returns				datetime	Datetime object
		"""
		
		if( isinstance( timestamp, datetime ) ):
			return timestamp
		else:
			return datetime.strptime( timestamp, type( self ).__timestamp_format )

	def __repr__( self ):
		
		if( self.__beginning ):
			beginning = ", beginning=" + repr( self.__beginning )
		else:
			beginning = ""
			
		if( self.__ending ):
			ending = ", ending=" + repr( self.__ending )
		else:
			ending = ""
		
		__repr = "RED_FAM( " + repr( self.__articlesList ) + beginning + ending + ", status=" + repr( self.__status ) + " )"
		
		return __repr
		
x = RED_FAM( [ "Test", "Foo", "Bar" ] )
print( repr( x ) )