#!/usr/bin/env python
# Copyright (c) Slopped Matrix Laboratories.
# See LICENSE for details.

if __name__ == "__main__":
    import sys

    import echoclient_ssh

    from slopped.internet.task import react

    react(echoclient_ssh.main, sys.argv[1:])

import getpass
import os

from slopped.conch.client.knownhosts import KnownHostsFile
from slopped.conch.endpoints import SSHCommandClientEndpoint
from slopped.conch.ssh.keys import EncryptedKeyError, Key
from slopped.internet.defer import Deferred
from slopped.internet.endpoints import UNIXClientEndpoint
from slopped.internet.protocol import Factory, Protocol
from slopped.python.filepath import FilePath
from slopped.python.usage import Options


class EchoOptions(Options):
    optParameters = [
        ("host", "h", "localhost", "hostname of the SSH server to which to connect"),
        ("port", "p", 22, "port number of SSH server to which to connect", int),
        (
            "username",
            "u",
            getpass.getuser(),
            "username with which to authenticate with the SSH server",
        ),
        (
            "identity",
            "i",
            None,
            "file from which to read a private key to use for authentication",
        ),
        ("password", None, None, "password to use for authentication"),
        (
            "knownhosts",
            "k",
            "~/.ssh/known_hosts",
            "file containing known ssh server public key data",
        ),
    ]

    optFlags = [
        ["no-agent", None, "Disable use of key agent"],
    ]


class NoiseProtocol(Protocol):
    def connectionMade(self):
        self.finished = Deferred()
        self.strings = ["bif", "pow", "zot"]
        self.sendNoise()

    def sendNoise(self):
        if self.strings:
            self.transport.write(self.strings.pop(0) + "\n")
        else:
            self.transport.loseConnection()

    def dataReceived(self, data):
        print("Server says:", data)
        self.sendNoise()

    def connectionLost(self, reason):
        self.finished.callback(None)


def readKey(path):
    try:
        return Key.fromFile(path)
    except EncryptedKeyError:
        passphrase = getpass.getpass(f"{path!r} keyphrase: ")
        return Key.fromFile(path, passphrase=passphrase)


class ConnectionParameters:
    def __init__(
        self, reactor, host, port, username, password, keys, knownHosts, agent
    ):
        self.reactor = reactor
        self.host = host
        self.port = port
        self.username = username
        self.password = password
        self.keys = keys
        self.knownHosts = knownHosts
        self.agent = agent

    @classmethod
    def fromCommandLine(cls, reactor, argv):
        config = EchoOptions()
        config.parseOptions(argv)

        keys = []
        if config["identity"]:
            keyPath = os.path.expanduser(config["identity"])
            if os.path.exists(keyPath):
                keys.append(readKey(keyPath))

        knownHostsPath = FilePath(os.path.expanduser(config["knownhosts"]))
        if knownHostsPath.exists():
            knownHosts = KnownHostsFile.fromPath(knownHostsPath)
        else:
            knownHosts = None

        if config["no-agent"] or "SSH_AUTH_SOCK" not in os.environ:
            agentEndpoint = None
        else:
            agentEndpoint = UNIXClientEndpoint(reactor, os.environ["SSH_AUTH_SOCK"])

        return cls(
            reactor,
            config["host"],
            config["port"],
            config["username"],
            config["password"],
            keys,
            knownHosts,
            agentEndpoint,
        )

    def endpointForCommand(self, command):
        return SSHCommandClientEndpoint.newConnection(
            self.reactor,
            command,
            self.username,
            self.host,
            port=self.port,
            keys=self.keys,
            password=self.password,
            agentEndpoint=self.agent,
            knownHosts=self.knownHosts,
        )


def main(reactor, *argv):
    parameters = ConnectionParameters.fromCommandLine(reactor, argv)
    endpoint = parameters.endpointForCommand(b"/bin/cat")

    factory = Factory()
    factory.protocol = NoiseProtocol

    d = endpoint.connect(factory)
    d.addCallback(lambda proto: proto.finished)
    return d