import logging
import serial
import time
logging.basicConfig(level=logging.DEBUG)

class Gsm:
    def __init__(self, port, msisdn, imei=None, pin=None):
        self.port = port
        logging.info('Initializing Gsm cass for port ' + port)
        try:
            self.console = serial.Serial(self.port, 112500, timeout=3)
        except:
            logging.error('Error connecting to ' + self.port)
        self.msisdn = msisdn
        #self.cmd("AT+CMGF=1")
        logging.info('Connection established')
        self.status = self.check_status()
        self.unlock_sim(pin)
        logging.info("Current status: " + str(self.status))
        if imei is not None:
            r = self.set_imei(imei)
            if r:
                self.imei = imei
                logging.info("IMEI Changed")

    def cmd(self, cmd):
        cmd += "\r\n"
        self.console.write(cmd.encode("ascii"))
        time.sleep(0.5)
        return list(map(lambda elem: elem.decode("ascii", errors="replace"), self.console.readlines()))

    def check_status(self):
        r = self.cmd("ATI")
        if "OK" in r:
            return True
        else:
            return False

    def unlock_sim(self, pin):
        status = self.cmd("AT+CPIN?")

        if status == "+CPIN:READY":
            return True
        elif "+CPIN:SIM PIN" in status:
            auth = self.cmd('AT+CPIN="' + pin + '"')
            if "OK" in auth:
                logging.info("Pin correct")
                return True
            else:
                logging.error("Wrong PIN")
                return False
        else:
            logging.error("Unknown PIN error")
            return False

    def set_imei(self, imei):
        r = self.cmd('AT+EMGR=1,7,"' + imei + '"')
        if "OK" in r:
            return True
        else:
            return False

    def fetch_messages(self):
        r = self.cmd("AT+CMGL=REC UNREAD")
        print(r)

    def delete_messages(self):
        r = self.cmd("")

    def parse_message(self, message):
        return True