# Copyright 2011 Quanta Research Cambridge, Inc.
#
#    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.
"""The entry point for the execution of a workloadTo execute a workload.
Users pass in a description of the workload and a nova manager object
to the bash_openstack function call"""

import datetime
import random
import time

from config import StressConfig
from state import ClusterState
from state import FloatingIpState
from state import KeyPairState
from state import VolumeState
from test_case import *
from tempest.common.utils.data_utils import rand_name
import utils.util

# setup logging to file
logging.basicConfig(
    format='%(asctime)s %(name)-20s %(levelname)-8s %(message)s',
    datefmt='%m-%d %H:%M:%S',
    filename="stress.debug.log",
    filemode="w",
    level=logging.DEBUG,
)

# define a Handler which writes INFO messages or higher to the sys.stdout
_console = logging.StreamHandler()
_console.setLevel(logging.INFO)
# set a format which is simpler for console use
_formatter = logging.Formatter('%(name)-20s: %(levelname)-8s %(message)s')
# tell the handler to use this format
_console.setFormatter(_formatter)
# add the handler to the root logger
logging.getLogger('').addHandler(_console)


def _create_cases(choice_spec):
    """
    Generate a workload of tests from workload description
    """
    cases = []
    count = 0
    for choice in choice_spec:
        p = choice.probability
        for i in range(p):
            cases.append(choice)
        i = i + p
        count = count + p
    assert(count == 100)
    return cases


def _get_compute_nodes(keypath, user, controller):
    """
    Returns a list of active compute nodes. List is generated by running
    nova-manage on the controller.
    """
    nodes = []
    if keypath is None or user is None:
        return nodes
    cmd = "nova-manage service list | grep ^nova-compute"
    lines = utils.util.ssh(keypath, user, controller, cmd).split('\n')
    # For example: nova-compute xg11eth0 nova enabled :-) 2011-10-31 18:57:46
    # This is fragile but there is, at present, no other way to get this info.
    for line in lines:
        words = line.split()
        if len(words) > 0 and words[4] == ":-)":
            nodes.append(words[1])
    return nodes


def _error_in_logs(keypath, logdir, user, nodes):
    """
    Detect errors in the nova log files on the controller and compute nodes.
    """
    grep = 'egrep "ERROR\|TRACE" %s/*.log' % logdir
    for node in nodes:
        errors = utils.util.ssh(keypath, user, node, grep, check=False)
        if len(errors) > 0:
            logging.error('%s: %s' % (node, errors))
            return True
    return False


def create_initial_vms(manager, state, count):
    image = manager.config.compute.image_ref
    flavor = manager.config.compute.flavor_ref
    servers = []
    logging.info('Creating %d vms' % count)
    for _ in xrange(count):
        name = rand_name('initial_vm-')
        _, server = manager.servers_client.create_server(name, image, flavor)
        servers.append(server)
    for server in servers:
        manager.servers_client.wait_for_server_status(server['id'], 'ACTIVE')
        logging.info('Server Name: %s Id: %s' % (name, server['id']))
        state.set_instance_state(server['id'], (server, 'ACTIVE'))


def create_initial_floating_ips(manager, state, count):
    logging.info('Creating %d floating ips' % count)
    for _ in xrange(count):
        _, ip = manager.floating_ips_client.create_floating_ip()
        logging.info('Ip: %s' % ip['ip'])
        state.add_floating_ip(FloatingIpState(ip))


def create_initial_keypairs(manager, state, count):
    logging.info('Creating %d keypairs' % count)
    for _ in xrange(count):
        name = rand_name('keypair-')
        _, keypair = manager.keypairs_client.create_keypair(name)
        logging.info('Keypair: %s' % name)
        state.add_keypair(KeyPairState(keypair))


def create_initial_volumes(manager, state, count):
    volumes = []
    logging.info('Creating %d volumes' % count)
    for _ in xrange(count):
        name = rand_name('volume-')
        _, volume = manager.volumes_client.create_volume(size=1,
                                                         display_name=name)
        volumes.append(volume)
    for volume in volumes:
        manager.volumes_client.wait_for_volume_status(volume['id'],
                                                      'available')
        logging.info('Volume Name: %s Id: %s' % (name, volume['id']))
        state.add_volume(VolumeState(volume))


def bash_openstack(manager,
                   choice_spec,
                   **kwargs):
    """
    Workload driver. Executes a workload as specified by the `choice_spec`
    parameter against a nova-cluster.

    `manager`  : Manager object
    `choice_spec` : list of BasherChoice actions to run on the cluster
    `kargs`       : keyword arguments to the constructor of `test_case`
                    `duration`   = how long this test should last (3 sec)
                    `sleep_time` = time to sleep between actions (in msec)
                    `test_name`  = human readable workload description
                                   (default: unnamed test)
                    `max_vms`    = maximum number of instances to launch
                                   (default: 32)
                    `seed`       = random seed (default: None)
    """
    stress_config = StressConfig(manager.config._conf)
    # get keyword arguments
    duration = kwargs.get('duration', datetime.timedelta(seconds=10))
    seed = kwargs.get('seed', None)
    sleep_time = float(kwargs.get('sleep_time', 3000)) / 1000
    max_vms = int(kwargs.get('max_vms', stress_config.max_instances))
    test_name = kwargs.get('test_name', 'unamed test')

    keypath = stress_config.host_private_key_path
    user = stress_config.host_admin_user
    logdir = stress_config.nova_logdir
    computes = _get_compute_nodes(keypath, user, manager.config.identity.host)
    utils.util.execute_on_all(keypath, user, computes,
                              "rm -f %s/*.log" % logdir)
    random.seed(seed)
    cases = _create_cases(choice_spec)
    state = ClusterState(max_vms=max_vms)
    create_initial_keypairs(manager, state,
                            int(kwargs.get('initial_keypairs', 0)))
    create_initial_vms(manager, state,
                       int(kwargs.get('initial_vms', 0)))
    create_initial_floating_ips(manager, state,
                                int(kwargs.get('initial_floating_ips', 0)))
    create_initial_volumes(manager, state,
                           int(kwargs.get('initial_volumes', 0)))
    test_end_time = time.time() + duration.seconds

    retry_list = []
    last_retry = time.time()
    cooldown = False
    logcheck_count = 0
    test_succeeded = True
    logging.debug('=== Test \"%s\" on %s ===' %
                  (test_name, time.asctime(time.localtime())))
    for kw in kwargs:
        logging.debug('\t%s = %s', kw, kwargs[kw])

    while True:
        if not cooldown:
            if time.time() < test_end_time:
                case = random.choice(cases)
                logging.debug('Chose %s' % case)
                retry = case.invoke(manager, state)
                if retry is not None:
                    retry_list.append(retry)
            else:
                logging.info('Cooling down...')
                cooldown = True
        if cooldown and len(retry_list) == 0:
            if _error_in_logs(keypath, logdir, user, computes):
                test_succeeded = False
            break
        # Retry verifications every 5 seconds.
        if time.time() - last_retry > 5:
            logging.debug('retry verifications for %d tasks', len(retry_list))
            new_retry_list = []
            for v in retry_list:
                v.check_timeout()
                if not v.retry():
                    new_retry_list.append(v)
            retry_list = new_retry_list
            last_retry = time.time()
        time.sleep(sleep_time)
        # Check error logs after 100 actions
        if logcheck_count > 100:
            if _error_in_logs(keypath, logdir, user, computes):
                test_succeeded = False
                break
            else:
                logcheck_count = 0
        else:
            logcheck_count = logcheck_count + 1
    # Cleanup
    logging.info('Cleaning up: terminating virtual machines...')
    vms = state.get_instances()
    active_vms = [v for _k, v in vms.iteritems()
                  if v and v[1] != 'TERMINATING']
    for target in active_vms:
        manager.servers_client.delete_server(target[0]['id'])
        # check to see that the server was actually killed
    for target in active_vms:
        kill_id = target[0]['id']
        i = 0
        while True:
            try:
                manager.servers_client.get_server(kill_id)
            except Exception:
                break
            i += 1
            if i > 60:
                _error_in_logs(keypath, logdir, user, computes)
                raise Exception("Cleanup timed out")
            time.sleep(1)
        logging.info('killed %s' % kill_id)
        state.delete_instance_state(kill_id)
    for floating_ip_state in state.get_floating_ips():
        manager.floating_ips_client.delete_floating_ip(
                                            floating_ip_state.resource_id)
    for keypair_state in state.get_keypairs():
        manager.keypairs_client.delete_keypair(keypair_state.name)
    for volume_state in state.get_volumes():
        manager.volumes_client.delete_volume(volume_state.resource_id)

    if test_succeeded:
        logging.info('*** Test succeeded ***')
    else:
        logging.info('*** Test had errors ***')
    return test_succeeded