#    Licensed to the Apache Software Foundation (ASF) under one
#    or more contributor license agreements.  See the NOTICE file
#    distributed with this work for additional information
#    regarding copyright ownership.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.
__all__ = [
    "Container"
]

import heapq
import logging

from pyngus.connection import Connection

LOG = logging.getLogger(__name__)


class Container(object):
    """An implementation of an AMQP 1.0 container."""
    def __init__(self, name, properties=None):
        self._name = name
        self._connections = {}
        self._properties = properties

    def destroy(self):
        conns = list(self._connections.values())
        for conn in conns:
            conn.destroy()

    @property
    def name(self):
        return self._name

    def create_connection(self, name, event_handler=None, properties=None):
        if name in self._connections:
            raise KeyError("connection '%s' already exists" % str(name))
        conn = Connection(self, name, event_handler, properties)
        if conn:
            self._connections[name] = conn
        return conn

    def need_processing(self):
        """A utility to help determine which connections need
        processing. Returns a triple of lists containing those connections that
        0) need to read from the network, 1) need to write to the network, 2)
        waiting for pending timers to expire.  The timer list is sorted with
        the connection next expiring at index 0.
        """
        readers = []
        writers = []
        timer_heap = []
        for c in iter(self._connections.values()):
            if c.needs_input > 0:
                readers.append(c)
            if c.has_output > 0:
                writers.append(c)
            if c.next_tick:
                heapq.heappush(timer_heap, (c.next_tick, c))
        timers = []
        while timer_heap:
            x = heapq.heappop(timer_heap)
            timers.append(x[1])

        return (readers, writers, timers)

    def resolve_sender(self, target_address):
        pass

    def resolve_receiver(self, source_address):
        pass

    def get_connection(self, name):
        return self._connections.get(name, None)

    def remove_connection(self, name):
        if name in self._connections:
            del self._connections[name]
