import re
import socket
import ssl

from nntp.tiny.socket   import Connection
from nntp.tiny.host     import Host
from nntp.tiny.response import Response, ResponseCode

class ClientException(Exception):
    pass

class ClientEOFException(ClientException):
    def __str__(self):
        return 'Unexpected client EOF'

class Client(Connection):
    RE_SPLIT = re.compile(r'\s+')

    def _read_response(self):
        line = self.readline()

        if line == '':
            return

        parts = self.RE_SPLIT.split(line.rstrip(), 1)

        if len(parts) == 0:
            return
        elif len(parts) == 1:
            return Response(ResponseCode(int(parts[0])))
        else:
            return Response(ResponseCode(int(parts[0])), parts[1])

    def __init__(self, host: str, port: int, tls: bool=False):
        sock = socket.create_connection((host, port))

        if tls:
            sslctx = ssl.create_default_context()
            sslctx.check_hostname = False
            sslctx.verify_mode    = ssl.CERT_NONE

            if Host.is_hostname(host):
                sock = sslctx.wrap_socket(sock, server_hostname=host)
            else:
                sock = sslctx.wrap_socket(sock)

        self.host = host
        self.port = port

        super().__init__(sock)

        response = self._read_response()

        if response is None:
            raise ClientException('Server not ready')

    def request(self, *args):
        self.print(' '.join(args))

        return self._read_response()

    def each_response_line(self):
        while True:
            line = self.readline()

            if line == '':
                raise ClientEOFException()

            line = line.rstrip()

            if line == '.':
                break

            yield line