# *******************************************************************************
# * Copyright (c) 2011 Wind River Systems, Inc. and others.
# * All rights reserved. This program and the accompanying materials
# * are made available under the terms of the Eclipse Public License v1.0
# * which accompanies this distribution, and is available at
# * http://www.eclipse.org/legal/epl-v10.html
# *
# * Contributors:
# *     Wind River Systems - initial API and implementation
# *******************************************************************************

"""
TCF - Target Communication Framework
"""

import types
import protocol, peer, channel
from util import task

__all__ = ('connect')

def connect(params, wait=True):
    """Connect to peer. Argument is a string of the form <transport>:<host>:<port>,
    e.g. "TCP:127.0.0.1:1534" """
    if type(params) is types.StringType:
        params = _parse_params(params)
    elif type(params) is not types.DictType:
        raise TypeError("Expected string or dict")
    p = peer.TransientPeer(params)
    if wait:
        c = task.Task(_openChannel, p).get()
    else:
        c = protocol.invokeAndWait(p.openChannel)
    return c

def peers():
    "Return list of discovered remote peers"
    locator = protocol.getLocator()
    if locator:
        return protocol.invokeAndWait(locator.getPeers)

def _openChannel(p, done=None):
    assert protocol.isDispatchThread()
    c = p.openChannel()
    if done is None: return
    class ChannelListener(channel.ChannelListener):
        def onChannelOpened(self):
            c.removeChannelListener(self)
            done(None, c)
        def onChannelClosed(self, error):
            done(error, None)
    c.addChannelListener(ChannelListener())

def _parse_params(paramStr):
    args = paramStr.split(":")
    if len(args) != 3:
        raise ValueError("Expected format: <transport>:<host>:<port>")
    transp, host, port = args
    return {
        peer.ATTR_IP_HOST : host,
        peer.ATTR_IP_PORT : port,
        peer.ATTR_TRANSPORT_NAME : transp
    }