from servicebase import ServiceBase
import paramiko
import re

class ServiceDelegate(ServiceBase) :

	connections = None

	def get_arguments(cls) :
		"""Returns an array of information used to construct an argumentparser argument."""
		return ['-r', '--vpn','store_true','Return VPN information about the subject (openvpn)']

	def startup(self) :
		for requirement in ['hosts','username','key'] :
			if requirement not in self.config or (requirement in self.config and self.config[requirement] is ''):
				self.error.append('Missing required config option ' + requirement)
				return
		self.hosts = self.config['hosts']
		self.debug('Logging into OpenVPN servers...',1)
		connections = {}
		for host in self.config['hosts'] :
			try :
				sshclient = paramiko.SSHClient()
				sshclient.set_missing_host_key_policy(paramiko.AutoAddPolicy())
				sshclient.connect(host,22,username=self.config['username'],password=self.config['key'])
				connections.update({host:sshclient})
			except Exception as exception :
				self.error.append('Unable to ssh into ' + host + ': ' + str(exception))
		self.connections = connections


	def shutdown(self) :
		for connection in self.connections.values() :
			connection.close()

	def lookup(self,subject) :
		search_command = 'sudo -S cat /var/log/openvpn/openvpn.log | grep \'primary virtual IP for\' | grep \'' + subject + '\' | tail -n 1'
		for host,connection in self.connections.items() :
			try:
				stdin,stdout,stderr=connection.exec_command(search_command)
				stdin.write(self.config['key'] + '\n')
				stdin.flush()
				result = stdout.readlines()
				if len(result) > 0 :
					self.debug('Retrieved line from ssh session: \n' + result[0],2)
					result = result[0]
				else :
					result = ''
				items = {'nat_address': r'.*\ ([0-9a-fA-F\.\:]*)$', 'source_address': r'.*/([0-9a-fA-F\.]*)\:.*', 'user_name': r'.*primary\ virtual\ IP\ for\ ([a-zA-Z0-9\.]*)/.*', 'timestamp': r'^([a-zA-Z]{3}\ +[0-9]{1,2}\ [0-9:]*)\ .*'}
				return_dictionary = {}
				for item in items.keys() :
					matches = re.match(items[item],result)
					if matches and len(matches.groups()) and matches[1] :
						return_dictionary.update({item: matches[1]})
				if len(return_dictionary) > 0 :
					return_dictionary.update({'host':host})
					return return_dictionary
				else :
					return None
			except Exception as exception :
				self.error.append('Unable to get results from ssh: ' + str(exception))
		pass