from twisted.python.reflect import namedClass

from landscape.service import LandscapeService, run_landscape_service
from landscape.manager.config import ManagerConfiguration
from landscape.broker.amp import RemoteBrokerConnector
from landscape.amp import ComponentPublisher
from landscape.manager.manager import Manager


class ManagerService(LandscapeService):
"""
The core Twisted Service which creates and runs all necessary managing
components when started.
"""

service_name = Manager.name

def __init__(self, config):
super(ManagerService, self).__init__(config)
self.plugins = self.get_plugins()
self.manager = Manager(self.reactor, self.config)
self.publisher = ComponentPublisher(self.manager, self.reactor,
self.config)

def get_plugins(self):
"""Return instances of all the plugins enabled in the configuration."""
return [namedClass("landscape.manager.%s.%s"
% (plugin_name.lower(), plugin_name))()
for plugin_name in self.config.plugin_factories]

def startService(self):
"""Start the manager service.

This method does 3 things, in this order:

- Start listening for connections on the manager socket.
- Connect to the broker.
- Add all configured plugins, that will in turn register themselves.
"""
super(ManagerService, self).startService()
self.publisher.start()

def start_plugins(broker):
self.broker = broker
self.manager.broker = broker
for plugin in self.plugins:
self.manager.add(plugin)
return self.broker.register_client(self.service_name)

self.connector = RemoteBrokerConnector(self.reactor, self.config)
connected = self.connector.connect()
return connected.addCallback(start_plugins)

def stopService(self):
"""Stop the manager and close the connection with the broker."""
self.connector.disconnect()
self.publisher.stop()
super(ManagerService, self).stopService()


def run(args):
run_landscape_service(ManagerConfiguration, ManagerService, args)