#!/usr/bin/python3 -u
#
import serial
import sys
import argparse
from datetime import datetime

serialPort='/dev/serial/by-id/usb-Prolific_Technology_Inc._USB-Serial_Controller-if00-port0'
serialBaud=57600
serialTimeout=1

doReset = False
enableMonitor = False

ser = serial.Serial(port=serialPort,
    baudrate = serialBaud,
    parity=serial.PARITY_NONE,
    stopbits=serial.STOPBITS_ONE,
    bytesize=serial.EIGHTBITS,
    timeout=serialTimeout)


parser = argparse.ArgumentParser()
parser.add_argument('--reset',
                    help='reset board via serial command, parameter is timeout in ms to reset.')
parser.add_argument('--monitor', default=False,
                    help='Monitor serial output.', action='store_true')
parser.add_argument('--addts', default=False,
                    help='Add timestamp to monitor output.', action='store_true')

args = parser.parse_args()
    
if args.reset:
    if int(args.reset) >= 1:
        doReset = True
        delayTime = args.reset

if doReset:
    cmdStr = 'reset ' + str(delayTime) + '\n'
    #print('cmd: >' + cmdStr + '<')
    cmdStr = cmdStr.encode('utf-8')
    ser.write(cmdStr)

if args.monitor:
    while True:
        #ser.flushInput()        
        #read buffer until cr/lf
        serLine = ser.readline().strip()
        # catch exception on invalid char coming in: UnicodeDecodeError: 'ascii' codec can't decode byte 0xf4 in position 6: ordinal not in range(128)
        try: 
            serLine = serLine.decode('ascii')
        except:
            serLine = ""
    
        if(serLine):
            if args.addts:
                #print (datetime.now().isoformat(), serLine)    #Echo the serial buffer bytes up to the CRLF back to screen
                print ("[" + str(datetime.now().strftime("%Y-%m-%d %H:%M:%S.%f")[:-3]) + "]:", serLine)
            else:
                print (serLine)    #Echo the serial buffer bytes up to the CRLF back to screen