# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.


from __future__ import print_function

from twisted.internet import defer, protocol, reactor
from twisted.conch import error
from twisted.conch.ssh import transport
from twisted.python import log



class SSHClientFactory(protocol.ClientFactory):

    def __init__(self, d, options, verifyHostKey, userAuthObject):
        self.d = d
        self.options = options
        self.verifyHostKey = verifyHostKey
        self.userAuthObject = userAuthObject


    def clientConnectionLost(self, connector, reason):
        if self.options['reconnect']:
            connector.connect()


    def clientConnectionFailed(self, connector, reason):
        if self.d is None:
            return
        d, self.d = self.d, None
        d.errback(reason)


    def buildProtocol(self, addr):
        trans = SSHClientTransport(self)
        if self.options['ciphers']:
            trans.supportedCiphers = self.options['ciphers']
        if self.options['macs']:
            trans.supportedMACs = self.options['macs']
        if self.options['compress']:
            trans.supportedCompressions[0:1] = ['zlib']
        if self.options['host-key-algorithms']:
            trans.supportedPublicKeys = self.options['host-key-algorithms']
        return trans



class SSHClientTransport(transport.SSHClientTransport):

    def __init__(self, factory):
        self.factory = factory
        self.unixServer = None


    def connectionLost(self, reason):
        if self.unixServer:
            d = self.unixServer.stopListening()
            self.unixServer = None
        else:
            d = defer.succeed(None)
        d.addCallback(lambda x:
            transport.SSHClientTransport.connectionLost(self, reason))


    def receiveError(self, code, desc):
        if self.factory.d is None:
            return
        d, self.factory.d = self.factory.d, None
        d.errback(error.ConchError(desc, code))


    def sendDisconnect(self, code, reason):
        if self.factory.d is None:
            return
        d, self.factory.d = self.factory.d, None
        transport.SSHClientTransport.sendDisconnect(self, code, reason)
        d.errback(error.ConchError(reason, code))


    def receiveDebug(self, alwaysDisplay, message, lang):
        log.msg('Received Debug Message: %s' % message)
        if alwaysDisplay: # XXX what should happen here?
            print(message)


    def verifyHostKey(self, pubKey, fingerprint):
        return self.factory.verifyHostKey(self, self.transport.getPeer().host, pubKey,
                                          fingerprint)


    def setService(self, service):
        log.msg('setting client server to %s' % service)
        transport.SSHClientTransport.setService(self, service)
        if service.name != 'ssh-userauth' and self.factory.d is not None:
            d, self.factory.d = self.factory.d, None
            d.callback(None)


    def connectionSecure(self):
        self.requestService(self.factory.userAuthObject)



def connect(host, port, options, verifyHostKey, userAuthObject):
    d = defer.Deferred()
    factory = SSHClientFactory(d, options, verifyHostKey, userAuthObject)
    reactor.connectTCP(host, port, factory)
    return d