"""
Support code for the C{landscape-message} utility, which sends a text
message to the Landscape web UI via the landscape-client's dbus
messaging service (see L{landscape.plugins.dbus_message}).
"""

import sys

from landscape.lib.log import log_failure
from landscape.reactor import LandscapeReactor
from landscape.broker.amp import RemoteBrokerConnector
from landscape.deployment import Configuration


class AcceptedTypeError(Exception):
"""
Raised when a message is sent without 'text-message' being an
accepted type.
"""


class EmptyMessageError(Exception):
"""Raised when an empty message is provied."""


def send_message(text, broker):
"""Add a message to the queue via a remote broker.

The message is of type C{text-message}.

@param broker: A connected L{RemoteBroker} object to use to send
the message.
@return: A L{Deferred} which will fire with the result of the send.
"""
def got_session_id(session_id):
response = broker.send_message(message, session_id, True)
return response

message = {"type": "text-message", "message": text}
result = broker.get_session_id()
result.addCallback(got_session_id)
return result


def got_result(result):
print u"Message sent."


def get_message(args):
encoding = sys.stdin.encoding or "UTF-8"
if len(args) < 2:
print ("Please enter your message, and send EOF (Control + D after "
"newline) when done.")
message = sys.stdin.read().decode(encoding)
else:
message = u" ".join([x.decode(encoding) for x in args[1:]])
if not message:
raise EmptyMessageError("Text messages may not be empty.")
return message


def got_accepted_types(accepted_types, broker, args):
if not "text-message" in accepted_types:
raise AcceptedTypeError("Text messages may not be created. Is "
"Landscape Client registered with the server?")
message = get_message(args)
d = send_message(message, broker)
d.addCallback(got_result)
return d


def run(args=sys.argv):
"""Send a message to Landscape.

This function runs a Twisted reactor, prints various status
messages, and exits the process.
"""
reactor = LandscapeReactor()
config = Configuration()
config.load(args)

def got_connection(broker):
result = broker.get_accepted_message_types()
return result.addCallback(got_accepted_types, broker, args)

def got_error(failure):
log_failure(failure)

connector = RemoteBrokerConnector(reactor, config)
result = connector.connect()
result.addCallback(got_connection)
result.addErrback(got_error)
result.addBoth(lambda x: connector.disconnect())

# For some obscure reason our LandscapeReactor.stop method calls
# reactor.crash() instead of reactor.stop(), which doesn't work
# here. Maybe LandscapeReactor.stop should simply use reactor.stop().
result.addBoth(lambda ignored: reactor.call_later(
0, reactor._reactor.stop))

reactor.run()

return result