import pygatt
import logging
from pygatt.util import uuid16_to_uuid
from pygatt.exceptions import NotConnectedError, NotificationTimeout
import binascii
from symbol import argument
try:
  from gi.repository import GObject
except ImportError:
  import gobject as GObject


logging.basicConfig()
logging.getLogger('pygatt').setLevel(logging.DEBUG)

"""
@param handle: indicate the handle from a characteristic
@param measure: value received from notification  
"""
def callback(handle, measure):
    if handle == 11: 
        print("Heart rate service received: ")
        
        
        for i in range(len(measure)):
            print str(measure[i])
        
    elif handle == 19:
        print("Battery service received: ")
        for i in range(len(measure)):
            print str(measure[i])
            
if __name__ == "__main__":    
	adapter = pygatt.GATTToolBackend()
	adapter.start()

	try:
		""" connect to bluetooth MAC addres with 10 seconds timeout"""
		device = adapter.connect('00:02:5B:00:15:10', 10)
		print(device)
		
		""" generate characteristics uuid's  """
		uuid_heart_service = uuid16_to_uuid(0x2A37)
		uuid_battery_service = uuid16_to_uuid(0x2A19)
		uuid_set_sensor_location = uuid16_to_uuid(0x2A39)
		uuid_get_sensor_location = uuid16_to_uuid(0x2A38)
		
		""" discover all characteristics uuid's"""
		device.discover_characteristics()
		
		
		"""subscribe(self, uuid, callback=None, indication=False):
		    
		Enable notifications or indications for a characteristic and register a
		callback function to be called whenever a new value arrives.

		@param: uuid -- UUID as a string of the characteristic to subscribe.
		@param callback -- function to be called when a notification/indication is
		            received on this characteristic.
		@param indication -- use indications (where each notificaiton is ACKd). This is
		            more reliable, but slower. 
		
		"""
		
		device.subscribe(uuid_heart_service, callback, False)
		device.subscribe(uuid_battery_service, callback, False)
		
		"""
		To send a message use function char_write(self, uuid, value, wait_for_response=False):
		
		@param uuid - uuid from what service will receive
		@param value - value to send
		@param wait_for_response - if a response from server is expected
		
		e.g
		device.char_write(uuid, value, False)
		"""
		
	except NotConnectedError:
		print NotConnectedError.message
		
	finally:
		try:
			val = device.char_read(uuid_get_sensor_location)
		   	print val[0]
		    
		except NotificationTimeout as e:
		    print e
		try:
			device.subscribe(uuid_heart_service, callback, False)
		   	device.subscribe(uuid_battery_service, callback, False)
		except NotConnectedError:
			print NotConnectedError.message
        
mainloop = GObject.MainLoop()
mainloop.run()