import json
import re
import socket

response_re = re.compile(r"(.*)\s+END\s*$")
key_val_re = re.compile(r'(?P<key>[^=]+)="?(?P<value>([^"]|\\")+)"?')


class Connector:
    """Connection to AF_UNIX or AF_INET, get and send data.

    Received data can be parsed from list of `key=value` or JSON.
    """

    socket_class = socket.socket
    """Socket class to instanciate on open."""
    socket = None
    """The socket."""
    address = None
    """String to a Unix domain socket file, or a tuple (host, port) for TCP/IP
    connection."""

    @property
    def is_open(self):
        return self.socket is not None

    def __init__(self, address=None):
        if address:
            self.address = address

    def __enter__(self):
        r = self.open()
        if r == -1:
            raise RuntimeError("can not open socket.")
        return self

    def __exit__(self):
        self.close()

    def open(self):
        """Open connection.

        :return: 0 (success), 1 (already opened), -1 (failure)
        """
        if self.is_open:
            return 1

        family = socket.AF_UNIX if isinstance(self.address, str) else socket.AF_INET
        try:
            self.socket = self.socket_class(family, socket.SOCK_STREAM)
            self.socket.connect(self.address)
            return 0
        except Exception:
            import traceback

            traceback.print_exc()
            self.close()
            return -1

    def close(self):
        if self.is_open:
            self.socket.close()
            self.socket = None

    # FIXME: return None on failed
    def send(self, *data, try_count=1, parse=False, parse_json=False):
        if self.open() == -1:
            return None

        data = bytes("".join([str(d) for d in data]) + "\n", encoding="utf-8")
        try:
            self.socket.sendall(data)
            resp = ""
            while not response_re.search(resp):
                resp += self.socket.recv(1024).decode("utf-8")

            if resp:
                resp = response_re.sub(r"\1", resp).strip()
                resp = self.parse(resp) if parse else self.parse_json(resp) if parse_json else resp
            return resp
        except Exception:
            self.close()
            if try_count > 0:
                return self.send(data, try_count - 1)

    def parse(self, value):
        return {
            line.groupdict()["key"]: line.groupdict()["value"]
            for line in (key_val_re.search(line) for line in value.split("\n"))
            if line
        }

    def parse_json(self, value):
        try:
            if value[0] == '"' and value[-1] == '"':
                value = value[1:-1]
            return json.loads(value) if value else None
        except Exception:
            return None