def parse_youtube_title(full_title):
	"""
	Parse song tags from youtube title.

	Current logic is to assumme the youtube title is always in format 'author-song title'.
	If there exists dashes in the title, up to the first dash is the author and the rest is the song title.
	If there are no dashes, return original title as song title.

	There will never be more than one dash because of the way we clean youtube titles.
	
	Return tuple (author_title, song_title)
	"""

	assert full_title.count('-') <= 1

	first_dash_index = full_title.find('-')

	if first_dash_index == -1:  # No dashes exist
		return (None, full_title)
	else:
		author = full_title[:first_dash_index].strip()
		song_title = full_title[first_dash_index + 1:].strip()

		return (author, song_title)