#!/usr/env python3


import datetime
import sys
import yaml


class BackupRotator:
	
	def __init__(self):
		
		self.__config = None
		self.__config_path = None
	
	def run(self):
		
		self.log("Begin")
		self.consume_arguments()
		self.consume_config(self.__config_path)
		
		self.rotate_paths()
	
	@staticmethod
	def current_time():
		
		now = datetime.datetime.now()
		now_s = now.strftime("%b-%d-%Y %I:%M%p")
		return str(now_s)
	
	def log(self, s, o=None):
		
		now = self.current_time()
		
		to_log = "[" + now + "][Backup Rotator] " + str(s)
		if o is not None:
			to_log += " " + str(o)
		
		print(to_log)
	
	def consume_arguments(self):
		
		for i in range(1, len(sys.argv)):
			
			arg = sys.argv[i]
			
			if arg == "--config":
				i, self.__config_path = self.consume_argument_companion(i)
				print("Found config path:", self.__config_path)
	
	@staticmethod
	def consume_argument_companion(arg_index):
	
		companion_index = arg_index + 1
		if companion_index >= len(sys.argv):
			raise Exception("Expected argument after", sys.argv[arg_index])
		
		return companion_index, sys.argv[companion_index]
	
	def consume_config(self, path=None):
	
		if path is None:
			raise Exception("Auto-finding of config file not implemented")
		
		f = open(path)
		self.__config = yaml.load(f)
		
		self.log("Consumed config from path: ", path)
	
	def rotate_paths(self):
		
		self.log("Begin rotating " + str(len(self.__config["paths"])) + " paths")
		for path in self.__config["paths"]:
			self.rotate_path(path)
	
	def rotate_path(self, path):
		
		self.log("Rotating path", path)


def main():
	
	rotator = BackupRotator()
	rotator.run()


if __name__ == "__main__":
	main()