#!/usr/bin/env python
# -*- coding: utf-8 -*-

__author__ = 'thomas'

import serial
import os
import argparse
##from datetime import datetime

verbosity=False

def log(param):
    if verbosity:
        print param

class BS21:
    def __init__(self, dev='/dev/tty.BS21-21-000000-0-A-SPPDev', pin='1234'):
        self.dev = dev
        self.pin = pin
        self.resp=None

    def openSerialPort(self):
        """
        open the serial port for the bluetooth SDP/RFCOMM connection
        """
        try:
            s = serial.Serial(
                port=self.dev,
                baudrate=115200,
                parity=serial.PARITY_NONE,
                stopbits=serial.STOPBITS_ONE,
                bytesize=serial.EIGHTBITS,
                timeout=10)
            #s.open()  ## is alerady open? Ouch!
        except serial.SerialException as e:
            print "ERROR: "+e.message
            s = None
            log("... failed to open the serial port!")
        return s

    def command(self, cmd):
        bs21 = self.openSerialPort()
        if bs21==None:
            log("something wrong, quitting")
            print "ERROR"
            exit()
        log("connection established, write command "+cmd+"...")
        bs21.write(cmd+"#"+ self.pin + "\r\n")
        log("command transmitted, now waiting for response...")
        resp = self.getResponse(bs21)
        dollar=(resp[0][0]=='$')
        if not dollar:
            log("unexpected response: "+self.resp)
            print "ERROR"
        elif resp[0]=='$OK':
            pass
        elif resp[0][1:3]=='BS':
            (hw, ver, unknown, hh, mm, ss) = resp[0].split(' ')
            (str_bs, str_21, serialId, state, str_A) = hw.split('-')
            print "Model "+str_bs[1:3]+"-"+str_21+" Serial ID="+serialId
            print "  Revision "+ver
            if state == '1':
                print "  Power switch = ON"
            elif state == '0':
                print "  Power switch = OFF"
            else:
                print "  Power switch = UNKNOWN ("+state+")"
            print "  Time: "+hh+":"+mm+":"+ss
        bs21.close()

    def getResponse(self, bs21):
        self.resp=bs21.readline().strip()
        log("... got response: '"+self.resp+"'")
        return self.resp.split('|')


if __name__=="__main__":
    parser = argparse.ArgumentParser(
        description='control Renkforce BS21 via Bluetooth',
        epilog='''
        Valid commands are either raw BS21 protocol like RELX, REL0, REL1, INFO, CLEAR00 (all uppercase)
        or complex commands (all lowercase):
            timer
            ...
        optional: store bluetooth device in environment variable $BS21_DEV and the PIN in $BS21_PIN
        ''')
    parser.add_argument('-v', '--verbose', help='increase verbosity', action="store_true")
    parser.add_argument('-d', '--device', type=str, help='path to the device file for bluetooth connection')
    parser.add_argument('-p', '--pin', type=str, help='the PIN to access BS21')
    parser.add_argument('command', type=str, nargs='+', help='command (+args) to execute')
    args = parser.parse_args()
    if args.pin:
        PIN=args.pin
    else:
        PIN=os.environ.get('BS21_PIN')
        if not PIN:
            PIN=raw_input("Enter the PIN: ").strip()
    if args.device:
        #TODO: check for existence
        DEV=args.device
    else:
        DEV=os.environ.get('BS21_DEV')
        if not DEV:
            #TODO: search for resonable device /dev/tty.BS....
            DEV="/dev/tty.BS-21-00NNNN-0-A-SPPDev"
    if args.verbose:
        verbosity=True
        print "calling BS21 with device=%s and PIN=%s" % (DEV, PIN)
    sw=BS21(DEV, PIN)
    sw.command(' '.join(args.command))