import os
import re
import hashlib
import lxml.html
from typing import List

from .atserver import AternosServer
from .atconnect import AternosConnect
from .aterrors import CredentialsError


class Client:

    """Aternos API Client class whose object contains user's auth data

    :param atconn: :class:`python_aternos.atconnect.AternosConnect`
    instance with initialized Aternos session
    :type atconn: python_aternos.atconnect.AternosConnect
    """

    def __init__(self, atconn: AternosConnect) -> None:

        self.atconn = atconn

    @classmethod
    def from_hashed(cls, username: str, md5: str):

        """Log in to Aternos with a username and a hashed password

        :param username: Your username
        :type username: str
        :param md5: Your password hashed with MD5
        :type md5: str
        :raises CredentialsError: If the API
        doesn't return a valid session cookie
        :return: Client instance
        :rtype: python_aternos.Client
        """

        atconn = AternosConnect()
        atconn.parse_token()
        atconn.generate_sec()

        credentials = {
            'user': username,
            'password': md5
        }

        loginreq = atconn.request_cloudflare(
            f'https://aternos.org/panel/ajax/account/login.php',
            'POST', data=credentials, sendtoken=True
        )

        if 'ATERNOS_SESSION' not in loginreq.cookies:
            raise CredentialsError(
                'Check your username and password'
            )

        return cls(atconn)

    @classmethod
    def from_credentials(cls, username: str, password: str):

        """Log in to Aternos with a username and a plain password

        :param username: Your username
        :type username: str
        :param password: Your password without any encryption
        :type password: str
        :return: Client instance
        :rtype: python_aternos.Client
        """

        md5 = Client.md5encode(password)
        return cls.from_hashed(username, md5)

    @classmethod
    def from_session(cls, session: str):

        """Log in to Aternos using a session cookie value

        :param session: Value of ATERNOS_SESSION cookie
        :type session: str
        :return: Client instance
        :rtype: python_aternos.Client
        """

        atconn = AternosConnect()
        atconn.session.cookies['ATERNOS_SESSION'] = session
        atconn.parse_token()
        atconn.generate_sec()

        return cls(atconn)

    @classmethod
    def restore_session(cls, file: str = '~/.aternos'):

        """Log in to Aternos using a saved ATERNOS_SESSION cookie

        :param file: File where a session cookie
        was saved, deafults to ~/.aternos
        :type file: str, optional
        :return: Client instance
        :rtype: python_aternos.Client
        """

        file = os.path.expanduser(file)
        with open(file, 'rt') as f:
            session = f.read().strip()
        return cls.from_session(session)

    @staticmethod
    def md5encode(passwd: str) -> str:

        """Encodes the given string with MD5

        :param passwd: String to encode
        :type passwd: str
        :return: Hexdigest hash of the string in lowercase
        :rtype: str
        """

        encoded = hashlib.md5(passwd.encode('utf-8'))
        return encoded.hexdigest().lower()

    def save_session(self, file: str = '~/.aternos') -> None:

        """Saves an ATERNOS_SESSION cookie to a file

        :param file: File where a session cookie
        must be saved, defaults to ~/.aternos
        :type file: str, optional
        """

        file = os.path.expanduser(file)
        with open(file, 'wt') as f:
            f.write(self.atconn.atsession)

    def list_servers(self) -> List[AternosServer]:

        """Parses a list of your servers from Aternos website

        :return: List of :class:`python_aternos.atserver.AternosServer` objects
        :rtype: list
        """

        serverspage = self.atconn.request_cloudflare(
            'https://aternos.org/servers/', 'GET'
        )
        serverstree = lxml.html.fromstring(serverspage.content)
        serverslist = serverstree.xpath(
            '//div[contains(@class,"servers ")]/div'
        )

        servers = []
        for server in serverslist:
            servid = server.xpath('./div[@class="server-body"]/@data-id')[0]
            servers.append(AternosServer(servid, self.atconn))

        return servers

    def get_server(self, servid: str) -> AternosServer:

        """Creates a server object from the server ID.
        Use this instead of list_servers if you know the ID to save some time.

        :return: :class:`python_aternos.atserver.AternosServer` object
        :rtype: python_aternos.atserver.AternosServer
        """

        return AternosServer(servid, self.atconn)

    def change_username(self, value: str) -> None:

        """Changes a username in your Aternos account

        :param value: New username
        :type value: str
        """

        self.atconn.request_cloudflare(
            'https://aternos.org/panel/ajax/account/username.php',
            'POST', data={'username': value}
        )

    def change_email(self, value: str) -> None:

        """Changes an e-mail in your Aternos account

        :param value: New e-mail
        :type value: str
        :raises ValueError: If an invalid
        e-mail address was passed to the function
        """

        email = re.compile(
            r'^[A-Za-z0-9\-_+.]+@[A-Za-z0-9\-_+.]+\.[A-Za-z0-9\-]+$|^$'
        )
        if not email.match(value):
            raise ValueError('Invalid e-mail!')

        self.atconn.request_cloudflare(
            'https://aternos.org/panel/ajax/account/email.php',
            'POST', data={'email': value}
        )

    def change_password(self, old: str, new: str) -> None:

        """Changes a password in your Aternos account

        :param old: Old password
        :type old: str
        :param new: New password
        :type new: str
        """

        old = Client.md5encode(old)
        new = Client.md5encode(new)
        self.atconn.request_cloudflare(
            'https://aternos.org/panel/ajax/account/password.php',
            'POST', data={
                'oldpassword': old,
                'newpassword': new
            }
        )