# ============LICENSE_START=======================================================
# Copyright (c) 2021 AT&T Intellectual Property. All rights reserved.
# ================================================================================
# 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.
# ============LICENSE_END=========================================================
"""
CLI parsing for the sync utility.
convert flags/env variables to configuration
"""
import argparse
import collections
import os
import sys
import logging
import logging.config
from urllib.parse import urlsplit
import yaml
import policysync.clients as clients
import policysync.coroutines
from .util import get_module_logger


logger = get_module_logger(__name__)

APPLICATION_JSON = "application/json"


Config = collections.namedtuple(
    'Config', ['out_file', 'check_period', 'filters', 'ids', 'client', 'bind'])


def parsecmd(args):
    """
    Parse the command into a config object
    :param args: arguments list for parsing
    :returns: Config for the policy sync
    """
    parser = argparse.ArgumentParser(
        description="Keeps a file updated with policies matching a filter.",
        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
    )

    parser.add_argument(
        "--out",
        type=str,
        default=os.environ.get("POLICY_SYNC_OUTFILE", "policies.json"),
        help="Output file to dump to",
    )

    parser.add_argument(
        "--duration",
        type=int,
        default=os.environ.get("POLICY_SYNC_DURATION", 1200),
        help="frequency (in seconds) to conduct periodic check",
    )

    parser.add_argument(
        "--filters",
        type=str,
        default=os.environ.get("POLICY_SYNC_FILTER", "[]"),
        help="Regex of policies that you are interested in.",
    )
    parser.add_argument(
        "--ids",
        type=str,
        default=os.environ.get("POLICY_SYNC_ID", "[]"),
        help="Specific names of policies you are interested in.",
    )

    parser.add_argument(
        "--pdp-user",
        type=str,
        default=os.environ.get("POLICY_SYNC_PDP_USER", None),
        help="PDP basic auth username",
    )
    parser.add_argument(
        "--pdp-pass",
        type=str,
        default=os.environ.get("POLICY_SYNC_PDP_PASS", None),
        help="PDP basic auth password",
    )

    parser.add_argument(
        "--pdp-url",
        type=str,
        default=os.environ.get("POLICY_SYNC_PDP_URL", None),
        help="PDP to connect to",
    )

    parser.add_argument(
        "--http-bind",
        type=str,
        default=os.environ.get("POLICY_SYNC_HTTP_BIND", "localhost:8000"),
        help="The bind address for container metrics",
    )

    parser.add_argument(
        "--http-metrics",
        type=bool,
        default=os.environ.get("POLICY_SYNC_HTTP_METRICS", True),
        help="turn on or off the prometheus metrics",
    )

    parser.add_argument(
        "--use-v0",
        type=bool,
        default=os.environ.get("POLICY_SYNC_V0_ENABLE", False),
        help="Turn on usage of the legacy v0 policy API",
    )

    parser.add_argument(
        "--logging-config",
        type=str,
        default=os.environ.get("POLICY_SYNC_LOGGING_CONFIG", None),
        help="Python formatted logging configuration file",
    )

    # V0 API specific configuration
    parser.add_argument(
        "--v0-notify-endpoint",
        type=str,
        default=os.environ.get(
            "POLICY_SYNC_V0_NOTIFIY_ENDPOINT", "pdp/notifications"
        ),
        help="Path of the v0 websocket notification",
    )

    parser.add_argument(
        "--v0-decision-endpoint",
        type=str,
        default=os.environ.get("POLICY_SYNC_V0_DECISION_ENDPOINT", "pdp/api"),
        help="path of the v0 decision endpoint",
    )

    # V1 API specific configuration
    parser.add_argument(
        "--v1-dmaap-topic",
        type=str,
        default=os.environ.get("POLICY_SYNC_V1_DMAAP_URL", None),
        help="URL of the dmaap topic used in v1 api for notifications",
    )

    parser.add_argument(
        "--v1-dmaap-user",
        type=str,
        default=os.environ.get("POLICY_SYNC_V1_DMAAP_USER", None),
        help="User to use with with the dmaap topic"
    )

    parser.add_argument(
        "--v1-dmaap-pass",
        type=str,
        default=os.environ.get("POLICY_SYNC_V1_DMAAP_PASS", None),
        help="Password to use with the dmaap topic"
    )

    parser.add_argument(
        "--v1-decision-endpoint",
        type=str,
        default=os.environ.get(
            "POLICY_SYNC_V1_PDP_DECISION_ENDPOINT",
            "policy/pdpx/v1/decision"
        ),
        help="Decision endpoint used in the v1 api for notifications",
    )

    args = parser.parse_args(args)

    if args.logging_config:
        logging.config.fileConfig(
            args.logging_config,
            disable_existing_loggers=False
        )
    else:
        handler = logging.StreamHandler()
        formatter = logging.Formatter(
            "[%(asctime)s][%(levelname)-5s]%(message)s"
        )
        root = logging.getLogger()
        handler.setFormatter(formatter)
        root.addHandler(handler)
        root.setLevel(logging.INFO)

    bind = args.http_bind if args.http_metrics else None

    client = clients.get_client(
        args.pdp_url,
        pdp_user=args.pdp_user,
        pdp_password=args.pdp_pass,
        use_v0=args.use_v0,
        v0_decision=args.v0_decision_endpoint,
        v0_notifications=args.v0_notify_endpoint,
        v1_decision=args.v1_decision_endpoint,
        dmaap_url=args.v1_dmaap_topic,
        dmaap_user=args.v1_dmaap_user,
        dmaap_password=args.v1_dmaap_pass
    )

    if bind is not None:
        bind = urlsplit("//" + bind)

    return Config(
        out_file=args.out,
        check_period=args.duration,
        filters=yaml.safe_load(args.filters),
        ids=yaml.safe_load(args.ids),
        client=client,
        bind=bind,
    )


def main():
    """
    Parse the arguments passed in via the command line and start the app
    """
    try:
        config = parsecmd(sys.argv[1:])
    except ValueError:
        logger.error(
            "There was no POLICY_SYNC_PDP_URL set or --pdp flag set"
        )
        return -1
    policysync.coroutines.start_event_loop(config)
    return 0