# ==================================================================================
#  Copyright (c) 2020 HCL Technologies Limited.
#
#  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.
# ==================================================================================
import time
import pandas as pd
from influxdb import DataFrameClient
from configparser import ConfigParser
from mdclogpy import Logger
from influxdb.exceptions import InfluxDBClientError, InfluxDBServerError
from requests.exceptions import RequestException, ConnectionError

logger = Logger(name=__name__)


class DATABASE(object):
    r""" DATABASE takes an input as database name. It creates a client connection
      to influxDB and It reads/ writes UE data for a given dabtabase and a measurement.


    Parameters
    ----------
    host: str (default='r4-influxdb.ricplt.svc.cluster.local')
        hostname to connect to InfluxDB
    port: int (default='8086')
        port to connect to InfluxDB
    username: str (default='root')
        user to connect
    password: str (default='root')
        password of the use

    Attributes
    ----------
    client: influxDB client
        DataFrameClient api to connect influxDB
    data: DataFrame
        fetched data from database
    """

    def __init__(self, dbname='Timeseries', user='root', password='root', host="r4-influxdb.ricplt", port='8086', path='', ssl=False):
        self.data = None
        self.host = host
        self.port = port
        self.user = user
        self.password = password
        self.path = path
        self.ssl = ssl
        self.dbname = dbname
        self.client = None
        self.config()

    def connect(self):
        if self.client is not None:
            self.client.close()

        try:
            self.client = DataFrameClient(self.host, port=self.port, username=self.user, password=self.password, path=self.path, ssl=self.ssl, database=self.dbname, verify_ssl=self.ssl)
            version = self.client.request('ping', expected_response_code=204).headers['X-Influxdb-Version']
            logger.info("Conected to Influx Database, InfluxDB version : {}".format(version))
            return True

        except (RequestException, InfluxDBClientError, InfluxDBServerError, ConnectionError):
            logger.error("Failed to establish a new connection with InflulxDB, Please check your url/hostname")
            time.sleep(120)

    def read_data(self, train=False, valid=False, limit=False):
        """Read data method for a given measurement and limit

        Parameters
        ----------
        meas: str (default='ueMeasReport')
        limit:int (defualt=False)
        """
        self.data = None
        query = 'select * from ' + self.meas
        if not train and not valid and not limit:
            query += ' where time>now()-1600ms'
        elif train:
            query += ' where time<now()-5m and time>now()-75m'
        elif valid:
            query += ' where time>now()-5m'
        elif limit:
            query += ' where time>now()-1m limit '+str(limit)
        result = self.query(query)
        if result and len(result[self.meas]) != 0:
            self.data = result[self.meas]

    def write_anomaly(self, df, meas='AD'):
        """Write data method for a given measurement

        Parameters
        ----------
        meas: str (default='AD')
        """
        try:
            self.client.write_points(df, meas)
        except (RequestException, InfluxDBClientError, InfluxDBServerError) as e:
            logger.error('Failed to send metrics to influxdb')
            print(e)

    def query(self, query):
        try:
            result = self.client.query(query)
        except (RequestException, InfluxDBClientError, InfluxDBServerError, ConnectionError) as e:
            logger.error('Failed to connect to influxdb: {}'.format(e))
            result = False
        return result

    def config(self):
        cfg = ConfigParser()
        cfg.read('src/ad_config.ini')
        for section in cfg.sections():
            if section == 'influxdb':
                self.host = cfg.get(section, "host")
                self.port = cfg.get(section, "port")
                self.user = cfg.get(section, "user")
                self.password = cfg.get(section, "password")
                self.path = cfg.get(section, "path")
                self.ssl = cfg.get(section, "ssl")
                self.dbname = cfg.get(section, "database")
                self.meas = cfg.get(section, "measurement")

            if section == 'features':
                self.thpt = cfg.get(section, "thpt")
                self.rsrp = cfg.get(section, "rsrp")
                self.rsrq = cfg.get(section, "rsrq")
                self.rssinr = cfg.get(section, "rssinr")
                self.prb = cfg.get(section, "prb_usage")
                self.ue = cfg.get(section, "ue")
                self.anomaly = cfg.get(section, "anomaly")


class DUMMY(DATABASE):

    def __init__(self):
        super().__init__()
        self.ue_data = pd.read_csv('src/ue.csv')

    def connect(self):
        return True

    def read_data(self, train=False, valid=False, limit=100000):
        if not train:
            self.data = self.ue_data.head(limit)
        else:
            self.data = self.ue_data.head(limit).drop(self.anomaly, axis=1)

    def write_anomaly(self, df, meas_name='AD'):
        pass

    def query(self, query=None):
        return {'UEReports': self.ue_data.head(1)}