##
# Copyright 2019 Telefonica Investigacion y Desarrollo, S.A.U.
# This file is part of OSM
# All Rights Reserved.
#
# 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.
#
# For those usages not covered by the Apache License, Version 2.0 please
# contact with: nfvlabs@tid.es
##
import asyncio
from typing import Union
import os
import yaml

from n2vc.k8s_helm_base_conn import K8sHelmBaseConnector
from n2vc.exceptions import K8sException


class K8sHelmConnector(K8sHelmBaseConnector):

    """
    ####################################################################################
    ################################### P U B L I C ####################################
    ####################################################################################
    """

    def __init__(
        self,
        fs: object,
        db: object,
        kubectl_command: str = "/usr/bin/kubectl",
        helm_command: str = "/usr/bin/helm",
        log: object = None,
        on_update_db=None,
    ):
        """
        Initializes helm connector for helm v2

        :param fs: file system for kubernetes and helm configuration
        :param db: database object to write current operation status
        :param kubectl_command: path to kubectl executable
        :param helm_command: path to helm executable
        :param log: logger
        :param on_update_db: callback called when k8s connector updates database
        """

        # parent class
        K8sHelmBaseConnector.__init__(
            self,
            db=db,
            log=log,
            fs=fs,
            kubectl_command=kubectl_command,
            helm_command=helm_command,
            on_update_db=on_update_db,
        )

        self.log.info("Initializing K8S Helm2 connector")

        # initialize helm client-only
        self.log.debug("Initializing helm client-only...")
        command = "{} init --client-only {} ".format(
            self._helm_command,
            "--stable-repo-url {}".format(self._stable_repo_url)
            if self._stable_repo_url
            else "--skip-repos",
        )
        try:
            asyncio.ensure_future(
                self._local_async_exec(command=command, raise_exception_on_error=False)
            )
            # loop = asyncio.get_event_loop()
            # loop.run_until_complete(self._local_async_exec(command=command,
            # raise_exception_on_error=False))
        except Exception as e:
            self.warning(
                msg="helm init failed (it was already initialized): {}".format(e)
            )

        self.log.info("K8S Helm2 connector initialized")

    async def install(
        self,
        cluster_uuid: str,
        kdu_model: str,
        kdu_instance: str,
        atomic: bool = True,
        timeout: float = 300,
        params: dict = None,
        db_dict: dict = None,
        kdu_name: str = None,
        namespace: str = None,
        **kwargs,
    ):
        """
        Deploys of a new KDU instance. It would implicitly rely on the `install` call
        to deploy the Chart/Bundle properly parametrized (in practice, this call would
        happen before any _initial-config-primitive_of the VNF is called).

        :param cluster_uuid: UUID of a K8s cluster known by OSM
        :param kdu_model: chart/reference (string), which can be either
            of these options:
            - a name of chart available via the repos known by OSM
              (e.g. stable/openldap, stable/openldap:1.2.4)
            - a path to a packaged chart (e.g. mychart.tgz)
            - a path to an unpacked chart directory or a URL (e.g. mychart)
        :param kdu_instance: Kdu instance name
        :param atomic: If set, installation process purges chart/bundle on fail, also
            will wait until all the K8s objects are active
        :param timeout: Time in seconds to wait for the install of the chart/bundle
            (defaults to Helm default timeout: 300s)
        :param params: dictionary of key-value pairs for instantiation parameters
            (overriding default values)
        :param dict db_dict: where to write into database when the status changes.
                        It contains a dict with {collection: <str>, filter: {},
                        path: <str>},
                            e.g. {collection: "nsrs", filter:
                            {_id: <nsd-id>, path: "_admin.deployed.K8S.3"}
        :param kdu_name: Name of the KDU instance to be installed
        :param namespace: K8s namespace to use for the KDU instance
        :param kwargs: Additional parameters (None yet)
        :return: True if successful
        """
        self.log.debug("installing {} in cluster {}".format(kdu_model, cluster_uuid))

        # sync local dir
        self.fs.sync(from_path=cluster_uuid)

        # init env, paths
        paths, env = self._init_paths_env(
            cluster_name=cluster_uuid, create_if_not_exist=True
        )

        await self._install_impl(
            cluster_uuid,
            kdu_model,
            paths,
            env,
            kdu_instance,
            atomic=atomic,
            timeout=timeout,
            params=params,
            db_dict=db_dict,
            kdu_name=kdu_name,
            namespace=namespace,
        )

        # sync fs
        self.fs.reverse_sync(from_path=cluster_uuid)

        self.log.debug("Returning kdu_instance {}".format(kdu_instance))
        return True

    async def inspect_kdu(self, kdu_model: str, repo_url: str = None) -> str:

        self.log.debug(
            "inspect kdu_model {} from (optional) repo: {}".format(kdu_model, repo_url)
        )

        return await self._exec_inspect_command(
            inspect_command="", kdu_model=kdu_model, repo_url=repo_url
        )

    """
    ####################################################################################
    ################################### P R I V A T E ##################################
    ####################################################################################
    """

    def _init_paths_env(self, cluster_name: str, create_if_not_exist: bool = True):
        """
        Creates and returns base cluster and kube dirs and returns them.
        Also created helm3 dirs according to new directory specification, paths are
        returned and also environment variables that must be provided to execute commands

        Helm 2 directory specification uses helm_home dir:

        The variables assigned for this paths are:
        - Helm hone: $HELM_HOME
        - helm kubeconfig: $KUBECONFIG

        :param cluster_name:  cluster_name
        :return: Dictionary with config_paths and dictionary with helm environment variables
        """
        base = self.fs.path
        if base.endswith("/") or base.endswith("\\"):
            base = base[:-1]

        # base dir for cluster
        cluster_dir = base + "/" + cluster_name

        # kube dir
        kube_dir = cluster_dir + "/" + ".kube"
        if create_if_not_exist and not os.path.exists(kube_dir):
            self.log.debug("Creating dir {}".format(kube_dir))
            os.makedirs(kube_dir)

        # helm home dir
        helm_dir = cluster_dir + "/" + ".helm"
        if create_if_not_exist and not os.path.exists(helm_dir):
            self.log.debug("Creating dir {}".format(helm_dir))
            os.makedirs(helm_dir)

        config_filename = kube_dir + "/config"

        # 2 - Prepare dictionary with paths
        paths = {
            "kube_dir": kube_dir,
            "kube_config": config_filename,
            "cluster_dir": cluster_dir,
            "helm_dir": helm_dir,
        }

        for file_name, file in paths.items():
            if "dir" in file_name and not os.path.exists(file):
                err_msg = "{} dir does not exist".format(file)
                self.log.error(err_msg)
                raise K8sException(err_msg)

        # 3 - Prepare environment variables
        env = {"HELM_HOME": helm_dir, "KUBECONFIG": config_filename}

        return paths, env

    async def _get_services(self, cluster_id, kdu_instance, namespace, kubeconfig):

        # init config, env
        paths, env = self._init_paths_env(
            cluster_name=cluster_id, create_if_not_exist=True
        )

        command1 = "env KUBECONFIG={} {} get manifest {} ".format(
            kubeconfig, self._helm_command, kdu_instance
        )
        command2 = "{} get --namespace={} -f -".format(self.kubectl_command, namespace)
        output, _rc = await self._local_async_exec_pipe(
            command1, command2, env=env, raise_exception_on_error=True
        )
        services = self._parse_services(output)

        return services

    async def _cluster_init(
        self, cluster_id: str, namespace: str, paths: dict, env: dict
    ):
        """
        Implements the helm version dependent cluster initialization:
        For helm2 it initialized tiller environment if needed
        """

        # check if tiller pod is up in cluster
        command = "{} --kubeconfig={} --namespace={} get deployments".format(
            self.kubectl_command, paths["kube_config"], namespace
        )
        output, _rc = await self._local_async_exec(
            command=command, raise_exception_on_error=True, env=env
        )

        output_table = self._output_to_table(output=output)

        # find 'tiller' pod in all pods
        already_initialized = False
        try:
            for row in output_table:
                if row[0].startswith("tiller-deploy"):
                    already_initialized = True
                    break
        except Exception:
            pass

        # helm init
        n2vc_installed_sw = False
        if not already_initialized:
            self.log.info(
                "Initializing helm in client and server: {}".format(cluster_id)
            )
            command = "{} --kubeconfig={} --namespace kube-system create serviceaccount {}".format(
                self.kubectl_command, paths["kube_config"], self.service_account
            )
            _, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=False, env=env
            )

            command = (
                "{} --kubeconfig={} create clusterrolebinding osm-tiller-cluster-rule "
                "--clusterrole=cluster-admin --serviceaccount=kube-system:{}"
            ).format(self.kubectl_command, paths["kube_config"], self.service_account)
            _, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=False, env=env
            )

            command = (
                "{} --kubeconfig={} --tiller-namespace={} --home={} --service-account {} "
                " {} init"
            ).format(
                self._helm_command,
                paths["kube_config"],
                namespace,
                paths["helm_dir"],
                self.service_account,
                "--stable-repo-url {}".format(self._stable_repo_url)
                if self._stable_repo_url
                else "--skip-repos",
            )
            _, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=True, env=env
            )
            n2vc_installed_sw = True
        else:
            # check client helm installation
            check_file = paths["helm_dir"] + "/repository/repositories.yaml"
            if not self._check_file_exists(
                filename=check_file, exception_if_not_exists=False
            ):
                self.log.info("Initializing helm in client: {}".format(cluster_id))
                command = (
                    "{} --kubeconfig={} --tiller-namespace={} "
                    "--home={} init --client-only {} "
                ).format(
                    self._helm_command,
                    paths["kube_config"],
                    namespace,
                    paths["helm_dir"],
                    "--stable-repo-url {}".format(self._stable_repo_url)
                    if self._stable_repo_url
                    else "--skip-repos",
                )
                output, _rc = await self._local_async_exec(
                    command=command, raise_exception_on_error=True, env=env
                )
            else:
                self.log.info("Helm client already initialized")

        repo_list = await self.repo_list(cluster_id)
        for repo in repo_list:
            if repo["name"] == "stable" and repo["url"] != self._stable_repo_url:
                self.log.debug("Add new stable repo url: {}")
                await self.repo_remove(cluster_id, "stable")
                if self._stable_repo_url:
                    await self.repo_add(cluster_id, "stable", self._stable_repo_url)
                break

        return n2vc_installed_sw

    async def _uninstall_sw(self, cluster_id: str, namespace: str):
        # uninstall Tiller if necessary

        self.log.debug("Uninstalling tiller from cluster {}".format(cluster_id))

        # init paths, env
        paths, env = self._init_paths_env(
            cluster_name=cluster_id, create_if_not_exist=True
        )

        if not namespace:
            # find namespace for tiller pod
            command = "{} --kubeconfig={} get deployments --all-namespaces".format(
                self.kubectl_command, paths["kube_config"]
            )
            output, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=False, env=env
            )
            output_table = self._output_to_table(output=output)
            namespace = None
            for r in output_table:
                try:
                    if "tiller-deploy" in r[1]:
                        namespace = r[0]
                        break
                except Exception:
                    pass
            else:
                msg = "Tiller deployment not found in cluster {}".format(cluster_id)
                self.log.error(msg)

            self.log.debug("namespace for tiller: {}".format(namespace))

        if namespace:
            # uninstall tiller from cluster
            self.log.debug("Uninstalling tiller from cluster {}".format(cluster_id))
            command = "{} --kubeconfig={} --home={} reset".format(
                self._helm_command, paths["kube_config"], paths["helm_dir"]
            )
            self.log.debug("resetting: {}".format(command))
            output, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=True, env=env
            )
            # Delete clusterrolebinding and serviceaccount.
            # Ignore if errors for backward compatibility
            command = (
                "{} --kubeconfig={} delete clusterrolebinding.rbac.authorization.k8s."
                "io/osm-tiller-cluster-rule"
            ).format(self.kubectl_command, paths["kube_config"])
            output, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=False, env=env
            )
            command = (
                "{} --kubeconfig={} --namespace {} delete serviceaccount/{}".format(
                    self.kubectl_command,
                    paths["kube_config"],
                    namespace,
                    self.service_account,
                )
            )
            output, _rc = await self._local_async_exec(
                command=command, raise_exception_on_error=False, env=env
            )

        else:
            self.log.debug("namespace not found")

    async def _instances_list(self, cluster_id):

        # init paths, env
        paths, env = self._init_paths_env(
            cluster_name=cluster_id, create_if_not_exist=True
        )

        command = "{} list --output yaml".format(self._helm_command)

        output, _rc = await self._local_async_exec(
            command=command, raise_exception_on_error=True, env=env
        )

        if output and len(output) > 0:
            # parse yaml and update keys to lower case to unify with helm3
            instances = yaml.load(output, Loader=yaml.SafeLoader).get("Releases")
            new_instances = []
            for instance in instances:
                new_instance = dict((k.lower(), v) for k, v in instance.items())
                new_instances.append(new_instance)
            return new_instances
        else:
            return []

    def _get_inspect_command(
        self, show_command: str, kdu_model: str, repo_str: str, version: str
    ):
        inspect_command = "{} inspect {} {}{} {}".format(
            self._helm_command, show_command, kdu_model, repo_str, version
        )
        return inspect_command

    def _get_get_command(
        self, get_command: str, kdu_instance: str, namespace: str, kubeconfig: str
    ):
        get_command = "env KUBECONFIG={} {} get {} {} --output yaml".format(
            kubeconfig, self._helm_command, get_command, kdu_instance
        )
        return get_command

    async def _status_kdu(
        self,
        cluster_id: str,
        kdu_instance: str,
        namespace: str = None,
        yaml_format: bool = False,
        show_error_log: bool = False,
    ) -> Union[str, dict]:

        self.log.debug(
            "status of kdu_instance: {}, namespace: {} ".format(kdu_instance, namespace)
        )

        # init config, env
        paths, env = self._init_paths_env(
            cluster_name=cluster_id, create_if_not_exist=True
        )
        command = ("env KUBECONFIG={} {} status {} --output yaml").format(
            paths["kube_config"], self._helm_command, kdu_instance
        )
        output, rc = await self._local_async_exec(
            command=command,
            raise_exception_on_error=True,
            show_error_log=show_error_log,
            env=env,
        )

        if yaml_format:
            return str(output)

        if rc != 0:
            return None

        data = yaml.load(output, Loader=yaml.SafeLoader)

        # remove field 'notes'
        try:
            del data.get("info").get("status")["notes"]
        except KeyError:
            pass

        # parse the manifest to a list of dictionaries
        if "manifest" in data:
            manifest_str = data.get("manifest")
            manifest_docs = yaml.load_all(manifest_str, Loader=yaml.SafeLoader)

            data["manifest"] = []
            for doc in manifest_docs:
                data["manifest"].append(doc)

        # parse field 'resources'
        try:
            resources = str(data.get("info").get("status").get("resources"))
            resource_table = self._output_to_table(resources)
            data.get("info").get("status")["resources"] = resource_table
        except Exception:
            pass

        # set description to lowercase (unify with helm3)
        try:
            data.get("info")["description"] = data.get("info").pop("Description")
        except KeyError:
            pass

        return data

    def _get_helm_chart_repos_ids(self, cluster_uuid) -> list:
        repo_ids = []
        cluster_filter = {"_admin.helm-chart.id": cluster_uuid}
        cluster = self.db.get_one("k8sclusters", cluster_filter)
        if cluster:
            repo_ids = cluster.get("_admin").get("helm_chart_repos") or []
            return repo_ids
        else:
            raise K8sException(
                "k8cluster with helm-id : {} not found".format(cluster_uuid)
            )

    async def _is_install_completed(self, cluster_id: str, kdu_instance: str) -> bool:
        # init config, env
        paths, env = self._init_paths_env(
            cluster_name=cluster_id, create_if_not_exist=True
        )

        status = await self._status_kdu(
            cluster_id=cluster_id, kdu_instance=kdu_instance, yaml_format=False
        )

        # extract info.status.resources-> str
        # format:
        #       ==> v1/Deployment
        #       NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
        #       halting-horse-mongodb   0/1     1            0           0s
        #       halting-petit-mongodb   1/1     1            0           0s
        # blank line
        resources = K8sHelmBaseConnector._get_deep(
            status, ("info", "status", "resources")
        )

        # convert to table
        resources = K8sHelmBaseConnector._output_to_table(resources)

        num_lines = len(resources)
        index = 0
        ready = True
        while index < num_lines:
            try:
                line1 = resources[index]
                index += 1
                # find '==>' in column 0
                if line1[0] == "==>":
                    line2 = resources[index]
                    index += 1
                    # find READY in column 1
                    if line2[1] == "READY":
                        # read next lines
                        line3 = resources[index]
                        index += 1
                        while len(line3) > 1 and index < num_lines:
                            ready_value = line3[1]
                            parts = ready_value.split(sep="/")
                            current = int(parts[0])
                            total = int(parts[1])
                            if current < total:
                                self.log.debug("NOT READY:\n    {}".format(line3))
                                ready = False
                            line3 = resources[index]
                            index += 1

            except Exception:
                pass

        return ready

    def _get_install_command(
        self,
        kdu_model,
        kdu_instance,
        namespace,
        params_str,
        version,
        atomic,
        timeout,
        kubeconfig,
    ) -> str:

        timeout_str = ""
        if timeout:
            timeout_str = "--timeout {}".format(timeout)

        # atomic
        atomic_str = ""
        if atomic:
            atomic_str = "--atomic"
        # namespace
        namespace_str = ""
        if namespace:
            namespace_str = "--namespace {}".format(namespace)

        # version
        version_str = ""
        if version:
            version_str = "--version {}".format(version)

        command = (
            "env KUBECONFIG={kubeconfig} {helm} install {atomic} --output yaml  "
            "{params} {timeout} --name={name} {ns} {model} {ver}".format(
                kubeconfig=kubeconfig,
                helm=self._helm_command,
                atomic=atomic_str,
                params=params_str,
                timeout=timeout_str,
                name=kdu_instance,
                ns=namespace_str,
                model=kdu_model,
                ver=version_str,
            )
        )
        return command

    def _get_upgrade_scale_command(
        self,
        kdu_model: str,
        kdu_instance: str,
        namespace: str,
        scale: int,
        version: str,
        atomic: bool,
        replica_str: str,
        timeout: float,
        resource_name: str,
        kubeconfig: str,
    ) -> str:
        """Generates the command to scale a Helm Chart release

        Args:
            kdu_model (str): Kdu model name, corresponding to the Helm local location or repository
            kdu_instance (str): KDU instance, corresponding to the Helm Chart release in question
            namespace (str): Namespace where this KDU instance is deployed
            scale (int): Scale count
            version (str): Constraint with specific version of the Chart to use
            atomic (bool): If set, upgrade process rolls back changes made in case of failed upgrade.
                The --wait flag will be set automatically if --atomic is used
            replica_str (str): The key under resource_name key where the scale count is stored
            timeout (float): The time, in seconds, to wait
            resource_name (str): The KDU's resource to scale
            kubeconfig (str): Kubeconfig file path

        Returns:
            str: command to scale a Helm Chart release
        """

        # scale
        if resource_name:
            scale_dict = {"{}.{}".format(resource_name, replica_str): scale}
        else:
            scale_dict = {replica_str: scale}

        scale_str = self._params_to_set_option(scale_dict)

        return self._get_upgrade_command(
            kdu_model=kdu_model,
            kdu_instance=kdu_instance,
            namespace=namespace,
            params_str=scale_str,
            version=version,
            atomic=atomic,
            timeout=timeout,
            kubeconfig=kubeconfig,
        )

    def _get_upgrade_command(
        self,
        kdu_model,
        kdu_instance,
        namespace,
        params_str,
        version,
        atomic,
        timeout,
        kubeconfig,
    ) -> str:
        """Generates the command to upgrade a Helm Chart release

        Args:
            kdu_model (str): Kdu model name, corresponding to the Helm local location or repository
            kdu_instance (str): KDU instance, corresponding to the Helm Chart release in question
            namespace (str): Namespace where this KDU instance is deployed
            params_str (str): Params used to upgrade the Helm Chart release
            version (str): Constraint with specific version of the Chart to use
            atomic (bool): If set, upgrade process rolls back changes made in case of failed upgrade.
                The --wait flag will be set automatically if --atomic is used
            timeout (float): The time, in seconds, to wait
            kubeconfig (str): Kubeconfig file path

        Returns:
            str: command to upgrade a Helm Chart release
        """

        timeout_str = ""
        if timeout:
            timeout_str = "--timeout {}".format(timeout)

        # atomic
        atomic_str = ""
        if atomic:
            atomic_str = "--atomic"

        # version
        version_str = ""
        if version:
            version_str = "--version {}".format(version)

        command = (
            "env KUBECONFIG={kubeconfig} {helm} upgrade {atomic} --output yaml {params} {timeout} "
            "--reuse-values {name} {model} {ver}"
        ).format(
            kubeconfig=kubeconfig,
            helm=self._helm_command,
            atomic=atomic_str,
            params=params_str,
            timeout=timeout_str,
            name=kdu_instance,
            model=kdu_model,
            ver=version_str,
        )
        return command

    def _get_rollback_command(
        self, kdu_instance, namespace, revision, kubeconfig
    ) -> str:
        return "env KUBECONFIG={} {} rollback {} {} --wait".format(
            kubeconfig, self._helm_command, kdu_instance, revision
        )

    def _get_uninstall_command(
        self, kdu_instance: str, namespace: str, kubeconfig: str
    ) -> str:
        return "env KUBECONFIG={} {} delete --purge  {}".format(
            kubeconfig, self._helm_command, kdu_instance
        )