import subprocess
import logging

logging.basicConfig()
log = logging.getLogger("checks")

class CheckException(Exception):
    pass

class WrongParameterException(CheckException):
    pass

class BaseCheck(object):

    def check(self):
        """ Should return tuple:
        (true/false, data)

        data is the raw result and can be saved in a database
        """
        pass



class DNSCheck(BaseCheck):
    def __init__(self, name, rr_type="AAAA", expected_result=None, server=None):

        self.rr_types = [ "AAAA", "A", "PTR", "TXT" ]
        self.name = name
        self.rr_type = rr_type
        self.server = server

        self.expected_result = expected_result

        if not self.rr_type in self.rr_types:
            raise WrongParameterException("Unsupported rr_type: {}".format(self.rr_type))

        self.command = self.rr_type_to_command()

    def rr_type_to_command(self):
        base_cmd="dig +short"

        if self.rr_type == "AAAA":
            command = "{} {} aaaa".format(base_cmd, self.name)
        elif self.rr_type == "A":
            command = "{} {} a".format(base_cmd, self.name)
        elif self.rr_type == "PTR":
            command = "-x {}".format(base_cmd, self.name)
        elif self.rr_type == "TXT":
            command = "{} {} txt".format(base_cmd, self.name)

        if self.server:
            command = "{} @{}".format(command, self.server)

        return command.split()


    def check(self):
        res = subprocess.run(self.command,
                             capture_output=True,
                             encoding="utf-8")

        if not res.returncode == 0:
            return (False, "")


        if self.expected_result:
            if not self.expected_result == res.stdout:
                return (False, res.stdout)

        else:
            if res.stdout == "":
                return (False, res.stdout)

        # Has (correct) data

        return (True, res.stdout)

    def __repr__(self):
        return "<Check {}>".format(self.__str__())

    def __str__(self):
        name = "{}/{}".format(self.name, self.rr_type)

        if self.server:
            name = "{}@{}".format(name, self.server)

        return name


class DFCheck(BaseCheck):
    def __init__(self, name, username="root", path="/"):
        self.name = name
        self.username = username
        self.path = path

        self.command = self.create_command()
        log.info("Command = {}".format(self.command))

    def create_command(self):
        base_command ='ssh {}@{}'.format(self.username, self.name).split()
        base_command.append("df {}".format(self.path))

        return base_command

    def check(self):
        res = subprocess.run(self.command,
                             capture_output=True,
                             encoding="utf-8")

        if not res.returncode == 0:
            return (False, "")

        return (True, res.stdout)

    def __repr__(self):
        return "<df {}>".format(self.__str__())

    def __str__(self):
        name = "{}:{}".format(self.name, self.path)

        return name