# -*- coding: utf-8 -*-
# BSD 2-Clause License
#
# Apprise - Push Notification Library.
# Copyright (c) 2023, Chris Caron <lead2gold@gmail.com>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

import os
import socket

from .NotifyBase import NotifyBase
from ..common import NotifyType
from ..utils import parse_bool
from ..AppriseLocale import gettext_lazy as _


class syslog:
    """
    Extrapoloated information from the syslog library so that this plugin
    would not be dependent on it.
    """
    # Notification Categories
    LOG_KERN = 0
    LOG_USER = 8
    LOG_MAIL = 16
    LOG_DAEMON = 24
    LOG_AUTH = 32
    LOG_SYSLOG = 40
    LOG_LPR = 48
    LOG_NEWS = 56
    LOG_UUCP = 64
    LOG_CRON = 72
    LOG_LOCAL0 = 128
    LOG_LOCAL1 = 136
    LOG_LOCAL2 = 144
    LOG_LOCAL3 = 152
    LOG_LOCAL4 = 160
    LOG_LOCAL5 = 168
    LOG_LOCAL6 = 176
    LOG_LOCAL7 = 184

    # Notification Types
    LOG_INFO = 6
    LOG_NOTICE = 5
    LOG_WARNING = 4
    LOG_CRIT = 2


class SyslogFacility:
    """
    All of the supported facilities
    """
    KERN = 'kern'
    USER = 'user'
    MAIL = 'mail'
    DAEMON = 'daemon'
    AUTH = 'auth'
    SYSLOG = 'syslog'
    LPR = 'lpr'
    NEWS = 'news'
    UUCP = 'uucp'
    CRON = 'cron'
    LOCAL0 = 'local0'
    LOCAL1 = 'local1'
    LOCAL2 = 'local2'
    LOCAL3 = 'local3'
    LOCAL4 = 'local4'
    LOCAL5 = 'local5'
    LOCAL6 = 'local6'
    LOCAL7 = 'local7'


SYSLOG_FACILITY_MAP = {
    SyslogFacility.KERN: syslog.LOG_KERN,
    SyslogFacility.USER: syslog.LOG_USER,
    SyslogFacility.MAIL: syslog.LOG_MAIL,
    SyslogFacility.DAEMON: syslog.LOG_DAEMON,
    SyslogFacility.AUTH: syslog.LOG_AUTH,
    SyslogFacility.SYSLOG: syslog.LOG_SYSLOG,
    SyslogFacility.LPR: syslog.LOG_LPR,
    SyslogFacility.NEWS: syslog.LOG_NEWS,
    SyslogFacility.UUCP: syslog.LOG_UUCP,
    SyslogFacility.CRON: syslog.LOG_CRON,
    SyslogFacility.LOCAL0: syslog.LOG_LOCAL0,
    SyslogFacility.LOCAL1: syslog.LOG_LOCAL1,
    SyslogFacility.LOCAL2: syslog.LOG_LOCAL2,
    SyslogFacility.LOCAL3: syslog.LOG_LOCAL3,
    SyslogFacility.LOCAL4: syslog.LOG_LOCAL4,
    SyslogFacility.LOCAL5: syslog.LOG_LOCAL5,
    SyslogFacility.LOCAL6: syslog.LOG_LOCAL6,
    SyslogFacility.LOCAL7: syslog.LOG_LOCAL7,
}

SYSLOG_FACILITY_RMAP = {
    syslog.LOG_KERN: SyslogFacility.KERN,
    syslog.LOG_USER: SyslogFacility.USER,
    syslog.LOG_MAIL: SyslogFacility.MAIL,
    syslog.LOG_DAEMON: SyslogFacility.DAEMON,
    syslog.LOG_AUTH: SyslogFacility.AUTH,
    syslog.LOG_SYSLOG: SyslogFacility.SYSLOG,
    syslog.LOG_LPR: SyslogFacility.LPR,
    syslog.LOG_NEWS: SyslogFacility.NEWS,
    syslog.LOG_UUCP: SyslogFacility.UUCP,
    syslog.LOG_CRON: SyslogFacility.CRON,
    syslog.LOG_LOCAL0: SyslogFacility.LOCAL0,
    syslog.LOG_LOCAL1: SyslogFacility.LOCAL1,
    syslog.LOG_LOCAL2: SyslogFacility.LOCAL2,
    syslog.LOG_LOCAL3: SyslogFacility.LOCAL3,
    syslog.LOG_LOCAL4: SyslogFacility.LOCAL4,
    syslog.LOG_LOCAL5: SyslogFacility.LOCAL5,
    syslog.LOG_LOCAL6: SyslogFacility.LOCAL6,
    syslog.LOG_LOCAL7: SyslogFacility.LOCAL7,
}

# Used as a lookup when handling the Apprise -> Syslog Mapping
SYSLOG_PUBLISH_MAP = {
    NotifyType.INFO: syslog.LOG_INFO,
    NotifyType.SUCCESS: syslog.LOG_NOTICE,
    NotifyType.FAILURE: syslog.LOG_CRIT,
    NotifyType.WARNING: syslog.LOG_WARNING,
}


class NotifyRSyslog(NotifyBase):
    """
    A wrapper for Remote Syslog Notifications
    """

    # The default descriptive name associated with the Notification
    service_name = 'Remote Syslog'

    # The services URL
    service_url = 'https://tools.ietf.org/html/rfc5424'

    # The default protocol
    protocol = 'rsyslog'

    # A URL that takes you to the setup/help of the specific protocol
    setup_url = 'https://github.com/caronc/apprise/wiki/Notify_rsyslog'

    # Disable throttle rate for RSyslog requests
    request_rate_per_sec = 0

    # Define object templates
    templates = (
        '{schema}://{host}',
        '{schema}://{host}:{port}',
        '{schema}://{host}/{facility}',
        '{schema}://{host}:{port}/{facility}',
    )

    # Define our template tokens
    template_tokens = dict(NotifyBase.template_tokens, **{
        'facility': {
            'name': _('Facility'),
            'type': 'choice:string',
            'values': [k for k in SYSLOG_FACILITY_MAP.keys()],
            'default': SyslogFacility.USER,
            'required': True,
        },
        'host': {
            'name': _('Hostname'),
            'type': 'string',
            'required': True,
        },
        'port': {
            'name': _('Port'),
            'type': 'int',
            'min': 1,
            'max': 65535,
            'default': 514,
        },
    })

    # Define our template arguments
    template_args = dict(NotifyBase.template_args, **{
        'facility': {
            # We map back to the same element defined in template_tokens
            'alias_of': 'facility',
        },
        'logpid': {
            'name': _('Log PID'),
            'type': 'bool',
            'default': True,
            'map_to': 'log_pid',
        },
    })

    def __init__(self, facility=None, log_pid=True, **kwargs):
        """
        Initialize RSyslog Object
        """
        super().__init__(**kwargs)

        if facility:
            try:
                self.facility = SYSLOG_FACILITY_MAP[facility]

            except KeyError:
                msg = 'An invalid syslog facility ' \
                      '({}) was specified.'.format(facility)
                self.logger.warning(msg)
                raise TypeError(msg)

        else:
            self.facility = \
                SYSLOG_FACILITY_MAP[
                    self.template_tokens['facility']['default']]

        # Include PID with each message.
        self.log_pid = log_pid

        return

    def send(self, body, title='', notify_type=NotifyType.INFO, **kwargs):
        """
        Perform RSyslog Notification
        """

        if title:
            # Format title
            body = '{}: {}'.format(title, body)

        # Always call throttle before any remote server i/o is made
        self.throttle()
        host = self.host
        port = self.port if self.port \
            else self.template_tokens['port']['default']

        if self.log_pid:
            payload = '<%d>- %d - %s' % (
                SYSLOG_PUBLISH_MAP[notify_type] + self.facility * 8,
                os.getpid(), body)

        else:
            payload = '<%d>- %s' % (
                SYSLOG_PUBLISH_MAP[notify_type] + self.facility * 8, body)

        # send UDP packet to upstream server
        self.logger.debug(
            'RSyslog Host: %s:%d/%s',
            host, port, SYSLOG_FACILITY_RMAP[self.facility])
        self.logger.debug('RSyslog Payload: %s' % str(payload))

        # our sent bytes
        sent = 0

        try:
            sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
            sock.settimeout(self.socket_connect_timeout)
            sent = sock.sendto(payload.encode('utf-8'), (host, port))
            sock.close()

        except socket.gaierror as e:
            self.logger.warning(
                'A connection error occurred sending RSyslog '
                'notification to %s:%d/%s', host, port,
                SYSLOG_FACILITY_RMAP[self.facility]
            )
            self.logger.debug('Socket Exception: %s' % str(e))
            return False

        except socket.timeout as e:
            self.logger.warning(
                'A connection timeout occurred sending RSyslog '
                'notification to %s:%d/%s', host, port,
                SYSLOG_FACILITY_RMAP[self.facility]
            )
            self.logger.debug('Socket Exception: %s' % str(e))
            return False

        if sent < len(payload):
            self.logger.warning(
                'RSyslog sent %d byte(s) but intended to send %d byte(s)',
                sent, len(payload))
            return False

        self.logger.info('Sent RSyslog notification.')

        return True

    def url(self, privacy=False, *args, **kwargs):
        """
        Returns the URL built dynamically based on specified arguments.
        """

        # Define any URL parameters
        params = {
            'logpid': 'yes' if self.log_pid else 'no',
        }

        # Extend our parameters
        params.update(self.url_parameters(privacy=privacy, *args, **kwargs))

        return '{schema}://{hostname}{port}/{facility}/?{params}'.format(
            schema=self.protocol,
            hostname=NotifyRSyslog.quote(self.host, safe=''),
            port='' if self.port is None
            or self.port == self.template_tokens['port']['default']
            else ':{}'.format(self.port),
            facility=self.template_tokens['facility']['default']
            if self.facility not in SYSLOG_FACILITY_RMAP
            else SYSLOG_FACILITY_RMAP[self.facility],
            params=NotifyRSyslog.urlencode(params),
        )

    @staticmethod
    def parse_url(url):
        """
        Parses the URL and returns enough arguments that can allow
        us to re-instantiate this object.

        """
        results = NotifyBase.parse_url(url, verify_host=False)
        if not results:
            # We're done early as we couldn't load the results
            return results

        tokens = []

        # Get our path values
        tokens.extend(NotifyRSyslog.split_path(results['fullpath']))

        # Initialization
        facility = None

        if tokens:
            # Store the last entry as the facility
            facility = tokens[-1].lower()

        # However if specified on the URL, that will over-ride what was
        # identified
        if 'facility' in results['qsd'] and len(results['qsd']['facility']):
            facility = results['qsd']['facility'].lower()

        if facility and facility not in SYSLOG_FACILITY_MAP:
            # Find first match; if no match is found we set the result
            # to the matching key.  This allows us to throw a TypeError
            # during the __init__() call. The benifit of doing this
            # check here is if we do have a valid match, we can support
            # short form matches like 'u' which will match against user
            facility = next((f for f in SYSLOG_FACILITY_MAP.keys()
                             if f.startswith(facility)), facility)

        # Save facility if set
        if facility:
            results['facility'] = facility

        # Include PID as part of the message logged
        results['log_pid'] = parse_bool(
            results['qsd'].get(
                'logpid',
                NotifyRSyslog.template_args['logpid']['default']))

        return results