import ftplib
import io

from routersploit.core.exploit.exploit import Exploit
from routersploit.core.exploit.exploit import Protocol
from routersploit.core.exploit.option import OptBool
from routersploit.core.exploit.printer import print_error
from routersploit.core.exploit.printer import print_success


FTP_TIMEOUT = 8.0


class FTPCli(object):
    """ FTP Client provides methods to handle communication with FTP server """

    def __init__(self, ftp_target: str, ftp_port: int, ssl: bool=False, verbosity: bool=False) -> None:
        """ FTP client constructor

        :param str ftp_target: target FTP server ip address
        :param int ftp_port: target FTP server port
        :param bool ssl: target FTP ssl enabled
        :param bool verbosity: display verbose output
        :return None:
        """

        self.ftp_target = ftp_target
        self.ftp_port = ftp_port
        self.verbosity = verbosity

        self.peer = "{}:{}".format(self.ftp_target, ftp_port)

        if ssl:
            self.ftp_client = ftplib.FTP_TLS()
        else:
            self.ftp_client = ftplib.FTP()

    def connect(self, retries: int=1) -> bool:
        """ Connect to FTP server

        :param int retries: number of retry attempts
        :return bool: True if connection was successful, False otherwise
        """

        for _ in range(retries):
            try:
                self.ftp_client.connect(self.ftp_target, self.ftp_port, timeout=FTP_TIMEOUT)
                return True
            except Exception as err:
                print_error(self.peer, "FTP Error while connecting to the server", err, verbose=self.verbosity)

            self.ftp_client.close()

        return False

    def login(self, username: str, password: str) -> bool:
        """ Login to FTP server

        :param str username: FTP account username
        :param str password: FTP account password
        :return bool: True if login was successful, False otherwise
        """

        try:
            self.ftp_client.login(username, password)
            print_success(self.peer, "FTP Authentication Successful - Username: '{}' Password: '{}'".format(username, password), verbose=self.verbosity)
            return True
        except Exception as err:
            print_error(self.peer, "FTP Authentication Failed - Username: '{}' Password: '{}'".format(username, password), verbose=self.verbosity)

        self.ftp_client.close()
        return False

    def test_connect(self) -> bool:
        """ Test connection to FTP server

        :return bool: True if connection was successful, False otherwise
        """

        if self.connect():
            self.ftp_client.close()
            return True

        return False

    def get_content(self, remote_file: str) -> str:
        """ Get remote file from FTP server

        :param str remote_file: remote file name
        :return str: remote file content
        """

        try:
            fp_content = io.BytesIO()
            self.ftp_client.retrbinary("RETR {}".format(remote_file), fp_content.write)
            return fp_content.getvalue()
        except Exception as err:
            print_error(self.peer, "FTP Error while retrieving content", err, verbose=self.verbosity)

        return None

    def close(self) -> bool:
        """ Close FTP connection

        :return bool: True if closing connection was successful, False otherwise
        """

        try:
            self.ftp_client.close()
            return True
        except Exception as err:
            print_error(self.peer, "FTP Error while closing connection", err, verbose=self.verbosity)

        return False


class FTPClient(Exploit):
    """ FTP Client exploit """

    target_protocol = Protocol.FTP

    ssl = OptBool(False, "SSL enabled: true/false")
    verbosity = OptBool(True, "Enable verbose output: true/false")

    def ftp_create(self, target: str=None, port: int=None) -> FTPCli:
        """ Create FTP client

        :param str target: target FTP server ip address
        :param int port: target FTP server port
        :return FTPCli: FTP client object
        """

        ftp_target = target if target else self.target
        ftp_port = port if port else self.port

        ftp_client = FTPCli(ftp_target, ftp_port, ssl=self.ssl, verbosity=self.verbosity)
        return ftp_client
