import enum
import socket
import re

from nntp.tiny.server   import Server, ServerCapability
from nntp.tiny.response import Response

class SessionState(enum.Flag):
    NONE      = 0
    AUTH_OK   = enum.auto()
    AUTH_POST = enum.auto()

from nntp.tiny.buffer import LineBuffer, BufferOverflow

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

    NNTP_VERSION = 2

    NNTP_CAPABILITIES = [
        'VERSION %d' % (self.NNTP_VERSION),
        'READER',
        'HDR',
        'NEWNEWS',
        'LIST ACTIVE NEWSGROUP OVERVIEW.FMT SUBSCRIPTIONS',
        'OVER MSGID'
    ]

    COMMANDS = {
        'capabilities': 
    }
    
    def __init__(self, server: Server, sock: socket.socket):
        self.server: Server      = server
        self.state: SessionState = SessionState.NONE
        self.sock: socket.socket = sock
        self.buf: LineBuffer     = LineBuffer()

    def readline(self):
        return self.buf.readline(self.sock)

    def print(self, text: str, end: str="\r\n"):
        return self.sock.send(bytes(text + end, 'ascii'))

    def end(self):
        return self.print('.')

    def respond(self, code: ResponseCode, message: str=None, body=None):
        response = Response(code, message, body)

        return self.print(str(response))

    def _cmd_capabilities(self, *args):
        self.respond(ResponseCode.NNTP_CAPABILITIES_FOLLOW)

        if self.state & SessionState.AUTH_POST:
            self.print('POST')

        if self.state & SessionState.AUTH_OK:
            self.print('AUTHUSER INFO')

        for item in self.NNTP_CAPABILITIES:
            self.print(item)

        self.end()

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

        if line == '':
            return

        command, args = self.RE_SPLIT.split(line.rstrip())