# 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.
# The ASF licenses this file to You 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.

from typing import List

import hashlib
import time

try:
    import simplejson as json
except ImportError:
    import json  # type: ignore

from libcloud.utils.py3 import httplib
from libcloud.utils.connection import get_response_object
from libcloud.common.types import InvalidCredsError
from libcloud.common.base import ConnectionUserAndKey, JsonResponse
from libcloud.http import LibcloudConnection

__all__ = [
    'OvhResponse',
    'OvhConnection'
]

API_HOST = 'api.ovh.com'
API_ROOT = '/1.0'
# From https://us.ovhcloud.com/about/company/data-centers
LOCATIONS = {
    'BHS1': {'id': 'BHS1', 'name': 'Beauharnois, Quebec 1', 'country': 'CA'},
    'BHS2': {'id': 'BHS2', 'name': 'Beauharnois, Quebec 2', 'country': 'CA'},
    'BHS3': {'id': 'BHS3', 'name': 'Beauharnois, Quebec 3', 'country': 'CA'},
    'BHS4': {'id': 'BHS4', 'name': 'Beauharnois, Quebec 4', 'country': 'CA'},
    'BHS5': {'id': 'BHS5', 'name': 'Beauharnois, Quebec 5', 'country': 'CA'},
    'BHS6': {'id': 'BHS6', 'name': 'Beauharnois, Quebec 6', 'country': 'CA'},
    'DC1': {'id': 'DC1', 'name': 'Paris DC1', 'country': 'FR'},
    'FRA1': {'id': 'FRA1', 'name': 'Frankfurt 1', 'country': 'DE'},
    'GRA1': {'id': 'GRA1', 'name': 'Gravelines 1', 'country': 'FR'},
    'GRA2': {'id': 'GRA2', 'name': 'Gravelines 2', 'country': 'FR'},
    'GSW': {'id': 'GSW', 'name': 'Paris GSW', 'country': 'FR'},
    'HIL1': {'id': 'HIL1', 'name': 'Hillsboro, Oregon 1', 'country': 'US'},
    'LON1': {'id': 'LON1', 'name': 'London 1', 'country': 'UK'},
    'P19': {'id': 'P19', 'name': 'Paris P19', 'country': 'FR'},
    'RBX1': {'id': 'RBX1', 'name': 'Roubaix 1', 'country': 'FR'},
    'RBX2': {'id': 'RBX2', 'name': 'Roubaix 2', 'country': 'FR'},
    'RBX3': {'id': 'RBX3', 'name': 'Roubaix 3', 'country': 'FR'},
    'RBX4': {'id': 'RBX4', 'name': 'Roubaix 4', 'country': 'FR'},
    'RBX5': {'id': 'RBX5', 'name': 'Roubaix 5', 'country': 'FR'},
    'RBX6': {'id': 'RBX6', 'name': 'Roubaix 6', 'country': 'FR'},
    'RBX7': {'id': 'RBX7', 'name': 'Roubaix 7', 'country': 'FR'},
    'SBG1': {'id': 'SBG1', 'name': 'Strasbourg 1', 'country': 'FR'},
    'SBG2': {'id': 'SBG2', 'name': 'Strasbourg 2', 'country': 'FR'},
    'SBG3': {'id': 'SBG3', 'name': 'Strasbourg 3', 'country': 'FR'},
    'SGP1': {'id': 'SGP1', 'name': 'Singapore 1', 'country': 'SG'},
    'SYD1': {'id': 'SYD1', 'name': 'Sydney 1', 'country': 'AU'},
    'VIN1': {'id': 'VIN1', 'name': 'Vint Hill, Virginia 1', 'country': 'US'},
    'WAW1': {'id': 'WAW1', 'name': 'Warsaw 1', 'country': 'PL'},
}
DEFAULT_ACCESS_RULES = [
    {'method': 'GET', 'path': '/*'},
    {'method': 'POST', 'path': '/*'},
    {'method': 'PUT', 'path': '/*'},
    {'method': 'DELETE', 'path': '/*'},
]


class OvhException(Exception):
    pass


class OvhResponse(JsonResponse):
    def parse_error(self):
        response = super(OvhResponse, self).parse_body()
        response = response or {}

        if response.get('errorCode', None) == 'INVALID_SIGNATURE':
            raise InvalidCredsError('Signature validation failed, probably '
                                    'using invalid credentials')

        return self.body


class OvhConnection(ConnectionUserAndKey):
    """
    A connection to the Ovh API

    Wraps SSL connections to the Ovh API, automagically injecting the
    parameters that the API needs for each request.
    """
    host = API_HOST
    request_path = API_ROOT
    responseCls = OvhResponse
    timestamp = None
    ua = []  # type: List[str]
    LOCATIONS = LOCATIONS
    _timedelta = None

    allow_insecure = True

    def __init__(self, user_id, *args, **kwargs):
        region = kwargs.pop('region', '')
        if region:
            self.host = ('%s.%s' % (region,
                                    API_HOST)).lstrip('.')
        else:
            self.host = API_HOST
        self.consumer_key = kwargs.pop('ex_consumer_key', None)
        if self.consumer_key is None:
            consumer_key_json = self.request_consumer_key(user_id)
            msg = ("Your consumer key isn't validated, "
                   "go to '%(validationUrl)s' for valid it. After instantiate "
                   "your driver with \"ex_consumer_key='%(consumerKey)s'\"." %
                   consumer_key_json)
            raise OvhException(msg)
        super(OvhConnection, self).__init__(user_id, *args, **kwargs)

    def request_consumer_key(self, user_id):
        action = self.request_path + '/auth/credential'
        data = json.dumps({
            'accessRules': DEFAULT_ACCESS_RULES,
            'redirection': 'http://ovh.com',
        })
        headers = {
            'Content-Type': 'application/json',
            'X-Ovh-Application': user_id,
        }
        httpcon = LibcloudConnection(host=self.host, port=443)

        try:
            httpcon.request(method='POST', url=action, body=data,
                            headers=headers)
        except Exception as e:
            handle_and_rethrow_user_friendly_invalid_region_error(
                host=self.host, e=e)

        response = OvhResponse(httpcon.getresponse(), httpcon)

        if response.status == httplib.UNAUTHORIZED:
            raise InvalidCredsError()

        json_response = response.parse_body()
        httpcon.close()
        return json_response

    def get_timestamp(self):
        if not self._timedelta:
            url = 'https://%s%s/auth/time' % (self.host, API_ROOT)
            response = get_response_object(url=url, method='GET', headers={})
            if not response or not response.body:
                raise Exception('Failed to get current time from Ovh API')

            timestamp = int(response.body)
            self._timedelta = timestamp - int(time.time())
        return int(time.time()) + self._timedelta

    def make_signature(self, method, action, params, data, timestamp):
        full_url = 'https://%s%s' % (self.host, action)
        if params:
            full_url += '?'
            for key, value in params.items():
                full_url += '%s=%s&' % (key, value)
            full_url = full_url[:-1]
        sha1 = hashlib.sha1()
        base_signature = "+".join([
            self.key,
            self.consumer_key,
            method.upper(),
            full_url,
            data if data else '',
            str(timestamp),
        ])
        sha1.update(base_signature.encode())
        signature = '$1$' + sha1.hexdigest()
        return signature

    def add_default_params(self, params):
        return params

    def add_default_headers(self, headers):
        headers.update({
            'X-Ovh-Application': self.user_id,
            'X-Ovh-Consumer': self.consumer_key,
            'Content-type': 'application/json',
        })
        return headers

    def request(self, action, params=None, data=None, headers=None,
                method='GET', raw=False):
        data = json.dumps(data) if data else None
        timestamp = self.get_timestamp()
        signature = self.make_signature(method, action, params, data,
                                        timestamp)
        headers = headers or {}
        headers.update({
            'X-Ovh-Timestamp': timestamp,
            'X-Ovh-Signature': signature
        })

        try:
            return super(OvhConnection, self)\
                .request(action, params=params, data=data, headers=headers,
                         method=method, raw=raw)
        except Exception as e:
            handle_and_rethrow_user_friendly_invalid_region_error(
                host=self.host, e=e)


def handle_and_rethrow_user_friendly_invalid_region_error(host, e):
    """
    Utility method which throws a more user-friendly error in case "name or
    service not known" error is received when sending a request.

    In most cases this error indicates user passed invalid ``region`` argument
    to the driver constructor.
    """
    msg = str(e).lower()

    if 'name or service not known' in msg or 'getaddrinfo failed' in msg:
        raise ValueError('Received "name or service not known" error '
                         'when sending a request. This likely '
                         'indicates invalid region argument was '
                         'passed to the driver constructor.'
                         'Used host: %s. Original error: %s' %
                         (host, str(e)))

    raise e