#
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# 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
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# software distributed under the License is distributed on an
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# KIND, either express or implied.  See the License for the
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# under the License.

from typing import Any, Dict

import requests
from airflow.exceptions import AirflowException
from airflow.hooks.base import BaseHook

OK_STATUS_CODE = 202


class OpenFaasHook(BaseHook):
    """
    Interact with OpenFaaS to query, deploy, invoke and update function

    :param function_name: Name of the function, Defaults to None
    :type function_name: str
    :param conn_id: openfaas connection to use, Defaults to open_faas_default
        for example host : http://openfaas.faas.com, Conn Type : Http
    :type conn_id: str
    """

    GET_FUNCTION = "/system/function/"
    INVOKE_ASYNC_FUNCTION = "/async-function/"
    INVOKE_FUNCTION = "/function/"
    DEPLOY_FUNCTION = "/system/functions"
    UPDATE_FUNCTION = "/system/functions"

    def __init__(
        self, function_name=None, conn_id: str = "open_faas_default", *args, **kwargs
    ) -> None:
        super().__init__(*args, **kwargs)
        self.function_name = function_name
        self.conn_id = conn_id

    def get_conn(self):
        conn = self.get_connection(self.conn_id)
        return conn

    def deploy_function(
        self, overwrite_function_if_exist: bool, body: Dict[str, Any]
    ) -> None:
        """Deploy OpenFaaS function"""
        if overwrite_function_if_exist:
            self.log.info(
                "Function already exist %s going to update", self.function_name
            )
            self.update_function(body)
        else:
            url = self.get_conn().host + self.DEPLOY_FUNCTION
            self.log.info("Deploying function %s", url)
            response = requests.post(url, body)
            if response.status_code != OK_STATUS_CODE:
                self.log.error("Response status %d", response.status_code)
                self.log.error("Failed to deploy")
                raise AirflowException("failed to deploy")
            else:
                self.log.info("Function deployed %s", self.function_name)

    def invoke_async_function(self, body: Dict[str, Any]) -> None:
        """Invoking function asynchronously"""
        url = self.get_conn().host + self.INVOKE_ASYNC_FUNCTION + self.function_name
        self.log.info("Invoking function asynchronously %s", url)
        response = requests.post(url, body)
        if response.ok:
            self.log.info("Invoked %s", self.function_name)
        else:
            self.log.error("Response status %d", response.status_code)
            raise AirflowException("failed to invoke function")

    def invoke_function(self, body: Dict[str, Any]) -> None:
        """Invoking function synchronously, will block until function completes and returns"""
        url = self.get_conn().host + self.INVOKE_FUNCTION + self.function_name
        self.log.info("Invoking function synchronously %s", url)
        response = requests.post(url, body)
        if response.ok:
            self.log.info("Invoked %s", self.function_name)
            self.log.info("Response code %s", response.status_code)
            self.log.info("Response %s", response.text)
        else:
            self.log.error("Response status %d", response.status_code)
            raise AirflowException("failed to invoke function")

    def update_function(self, body: Dict[str, Any]) -> None:
        """Update OpenFaaS function"""
        url = self.get_conn().host + self.UPDATE_FUNCTION
        self.log.info("Updating function %s", url)
        response = requests.put(url, body)
        if response.status_code != OK_STATUS_CODE:
            self.log.error("Response status %d", response.status_code)
            self.log.error(
                "Failed to update response %s", response.content.decode("utf-8")
            )
            raise AirflowException("failed to update " + self.function_name)
        else:
            self.log.info("Function was updated")

    def does_function_exist(self) -> bool:
        """Whether OpenFaaS function exists or not"""
        url = self.get_conn().host + self.GET_FUNCTION + self.function_name

        response = requests.get(url)
        if response.ok:
            return True
        else:
            self.log.error("Failed to find function %s", self.function_name)
            return False