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# to you under the Apache License, Version 2.0 (the
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#
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import json

import yandexcloud

from airflow.exceptions import AirflowException
from airflow.hooks.base_hook import BaseHook


class YandexCloudBaseHook(BaseHook):
    """
    A base hook for Yandex.Cloud related tasks.

    :param connection_id: The connection ID to use when fetching connection info.
    :type connection_id: str
    """

    def __init__(self, connection_id=None, default_folder_id=None, default_public_ssh_key=None):
        super().__init__()
        self.connection_id = connection_id or 'yandexcloud_default'
        self.connection = self.get_connection(self.connection_id)
        self.extras = self.connection.extra_dejson
        credentials = self._get_credentials()
        self.sdk = yandexcloud.SDK(**credentials)
        self.default_folder_id = default_folder_id or self._get_field('folder_id', False)
        self.default_public_ssh_key = default_public_ssh_key or self._get_field('public_ssh_key', False)
        self.client = self.sdk.client

    def _get_credentials(self):
        service_account_json_path = self._get_field('service_account_json_path', False)
        service_account_json = self._get_field('service_account_json', False)
        oauth_token = self._get_field('oauth', False)
        if not (service_account_json or oauth_token or service_account_json_path):
            raise AirflowException(
                'No credentials are found in connection. Specify either service account '
                + 'authentication JSON or user OAuth token in Yandex.Cloud connection'
            )
        if service_account_json_path:
            with open(service_account_json_path) as infile:
                service_account_json = infile.read()
        if service_account_json:
            service_account_key = json.loads(service_account_json)
            return {'service_account_key': service_account_key}
        else:
            return {'token': oauth_token}

    def _get_field(self, field_name, default=None):
        """
        Fetches a field from extras, and returns it.
        """
        long_f = f'extra__yandexcloud__{field_name}'
        if hasattr(self, 'extras') and long_f in self.extras:
            return self.extras[long_f]
        else:
            return default
