import socket

from transport.base import TransportBase


class Transport(TransportBase):
    def __init__(self, config):
        super().__init__(config)

        self.listener = self.__connect(config['host'], config['port'])
        self.buffer = bytearray()

    def writeline(self, cmd_str):
        response_string = cmd_str + "\n"
        self.conn.sendall(bytes(response_string, 'utf-8'))

    def readline(self):
        data = self.conn.recv(16)  # команды все короткие, нет смысла много читать из буфера
        # print('data: ', data)
        if not data:
            return ''

        line = self.__findLine(data)

        return line

    def close(self):
        self.listener.close()

    def __connect(self, host='127.0.0.1', port=12345):
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as socket_listener:
            socket_listener.bind((host, port))
            socket_listener.listen()

            conn, addr = socket_listener.accept()
            self.conn = conn
            return socket_listener

    def __findLine(self, data):
        data_chunk = bytearray(self.buffer)
        data_chunk.extend(data)

        # print("line: ", data_chunk)
        line_separator_index = data_chunk.find(b"\n")
        # print('n idx: ', line_separator_index)

        if line_separator_index > 0:
            line = data_chunk[0: line_separator_index]
            self.buffer = data_chunk[line_separator_index+1:]

            return line.decode('utf-8')