import serial
import serial.tools.list_ports
import time, sched

def wait_for_ack():
	while True: # wait for the '*' character
		new_char = io.read()
		timeouts = 0
		if new_char == '':
			timeouts += 1
			if timeouts >= 5:
				break
		if new_char == '*':
			break



# Search for and connect to the stepper board
initialized = False
io = None
def init():
	global io
	import serial.tools.list_ports #try to find the device's port number
	for port in serial.tools.list_ports.comports():
		if 'Stepperboard' in port[1]:
			stepper_port = port[0]
			print "Stepper found on port " + str(stepper_port)
			break
	else:
		debug_msg("Tried to initialize. Stepper Board not found in port list.")
		return False
	
	try:
		io.close() #if the port's open, close it
	except Exception:
		pass
		
	try:
		io = serial.Serial( #try to open the serial port
			port=stepper_port,
			baudrate=115200,
			bytesize=serial.EIGHTBITS,
			stopbits=serial.STOPBITS_ONE,
			timeout=0.1
			)
	except Exception:
		return False
	
	print "Stepperboard found and initialized!"
	return True #Awesome, we made it through! Board is initialized.

#test the limits and center the gun between them in both axis.	
def zero_center():
	io.write("B1000R")
	io.write("X10000GI")
	while '*' not in io.read():
		pass
	io.flushInput()
	io.write("X-1?")
	received_string = ''
	while True:
		byte = io.read()
		if byte == '*':
			break
		else:
			received_string += byte
	x_lim_plus = int(received_string.strip()[5:])
	print "plus limit = " + str(x_lim_plus)
	
	io.flushInput()
	io.write("X-10000GI")
	while '*' not in io.read():
		pass
	io.write("X-1?")
	received_string = ''
	while True:
		byte = io.read()
		if byte == '*':
			break
		else:
			received_string += byte
	x_lim_minus = int(received_string.strip()[5:])
	print "minus limit = " + str(x_lim_minus)
	x_range = x_lim_plus - x_lim_minus
	print "X total step range: " + str(x_range)
	io.write("X2000R") #ok, got the data we need, return to operating speed
	new_x_lim_minus = 0-(x_range/2)
	io.write("X" + str(new_x_lim_minus) + "=")
	while '*' not in io.read():
		pass
	io.write("X0GI")
	while '*' not in io.read():
		pass
	# OK, that's it for X!
	io.write("Y10000GI")
	while '*' not in io.read():
		pass
	io.flushInput()
	io.write("Y-1?")
	received_string = ''
	while True:
		byte = io.read()
		if byte == '*':
			break
		else:
			received_string += byte
	y_lim_plus = int(received_string.strip()[5:])
	print "plus limit = " + str(y_lim_plus)
	
	io.flushInput()
	io.write("Y-10000GI")
	while '*' not in io.read():
		pass
	io.write("Y-1?")
	received_string = ''
	while True:
		byte = io.read()
		if byte == '*':
			break
		else:
			received_string += byte
	y_lim_minus = int(received_string.strip()[5:])
	print "minus limit = " + str(y_lim_minus)
	y_range = y_lim_plus - y_lim_minus
	print "Y total step range: " + str(y_range)
	io.write("Y2000R") #ok, got the data we need, return to operating speed
	new_y_lim_minus = 0-(y_range/2)
	io.write("Y" + str(new_y_lim_minus) + "=")
	while '*' not in io.read():
		pass
	io.write("Y0GI")
	while '*' not in io.read():
		pass
	print "Leveling"
	io.write("Y-675GI");
	while '*' not in io.read():
		pass
	io.write("Y0=")
	while '*' not in io.read():
		pass
	print "Turret zeroed!"
	io.flushInput()

	
if (__name__ == "__main__"):
	init()
	zero_center()
	#track_target()