#
#    NEPI, a framework to manage network experiments
#    Copyright (C) 2013 INRIA
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Author: Alina Quereilhac <alina.quereilhac@inria.fr>

from nepi.execution.attribute import Attribute, Flags, Types
from nepi.execution.trace import Trace, TraceAttr
from nepi.execution.resource import ResourceManager, clsinit_copy, ResourceState, \
    ResourceAction
from nepi.resources.linux.application import LinuxApplication
from nepi.resources.linux.ccn.ccnr import LinuxCCNR
from nepi.resources.linux.node import OSType

from nepi.util.sshfuncs import ProcStatus
from nepi.util.timefuncs import strfnow, strfdiff
import os

reschedule_delay = "0.5s"

@clsinit_copy
class LinuxCCNR(LinuxApplication):
    _rtype = "LinuxCCNContent"

    @classmethod
    def _register_attributes(cls):
        content_name = Attribute("contentName",
                "The name of the content to publish (e.g. ccn:/VIDEO) ",
            flags = Flags.ExecReadOnly)
        content = Attribute("content",
                "The content to publish. It can be a path to a file or plain text ",
            flags = Flags.ExecReadOnly)


        cls._register_attribute(content_name)
        cls._register_attribute(content)

    @classmethod
    def _register_traces(cls):
        log = Trace("log", "CCND log output")

        cls._register_trace(log)

    def __init__(self, ec, guid):
        super(LinuxCCNContent, self).__init__(ec, guid)

    @property
    def ccnr(self):
        ccnr = self.get_connected(LinuxCCNR.rtype())
        if ccnr: return ccnr[0]
        return None

    def deploy(self):
        if not self.get("command"):
            self.set("command", self._default_command)
        
        if not self.get("env"):
            self.set("env", self._default_environment)

        # Wait until associated ccnd is provisioned
        ccnr = self.ccnr

        if not ccnr or ccnr.state < ResourceState.STARTED:
            self.ec.schedule(reschedule_delay, self.deploy)
        else:
            # Add a start after condition so CCNR will not start
            # before CCND does
            self.ec.register_condition(self.guid, ResourceAction.START, 
                ccnd.guid, ResourceState.STARTED)
 
            # Invoke the actual deployment
            super(LinuxCCNContent, self).deploy()

    @property
    def _default_command(self):
        return "ccnseqwriter -r %s " % self.get("contentName")

    @property
    def _default_environment(self):
        env = "PATH=$PATH:${EXP_HOME}/ccnx/bin "
        return env            
        
    def valid_connection(self, guid):
        # TODO: Validate!
        return True