import tornado
import tornado.web
import tornado.gen
from tornado.ioloop import IOLoop
from objects import glob

class asyncRequestHandler(tornado.web.RequestHandler):
	"""
	Tornado asynchronous request handler
	create a class that extends this one (requestHelper.asyncRequestHandler)
	use asyncGet() and asyncPost() instad of get() and post().
	Done. I'm not kidding.
	"""
	@tornado.web.asynchronous
	@tornado.gen.engine
	def get(self, *args, **kwargs):
		yield tornado.gen.Task(runBackground, (self.asyncGet, tuple(args), dict(kwargs)))

	@tornado.web.asynchronous
	@tornado.gen.engine
	def post(self, *args, **kwargs):
		yield tornado.gen.Task(runBackground, (self.asyncPost, tuple(args), dict(kwargs)))

	def asyncGet(self, *args, **kwargs):
		self.send_error(405)
		self.finish()

	def asyncPost(self, *args, **kwargs):
		self.send_error(405)
		self.finish()

	def getRequestIP(self):
		realIP = self.request.headers.get("X-Real-IP")
		if realIP != None:
			return realIP
		return self.request.remote_ip


def runBackground(data, callback):
	"""
	Run a function in the background.
	Used to handle multiple requests at the same time
	"""
	func, args, kwargs = data
	def _callback(result):
		IOLoop.instance().add_callback(lambda: callback(result))
	glob.pool.apply_async(func, args, kwargs, _callback)


def checkArguments(arguments, requiredArguments):
	"""
	Check that every requiredArguments elements are in arguments

	arguments -- full argument list, from tornado
	requiredArguments -- required arguments list es: ["u", "ha"]
	handler -- handler string name to print in exception. Optional
	return -- True if all arguments are passed, none if not
	"""
	for i in requiredArguments:
		if i not in arguments:
			return False
	return True

def printArguments(t):
	"""
	Print passed arguments, for debug purposes

	t -- tornado object (self)
	"""
	print("ARGS::")
	for i in t.request.arguments:
		print ("{}={}".format(i, t.get_argument(i)))