#!/usr/bin/env python3
#  Copyright 2023 Google LLC
#
#  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.

"""
Tools to run Google Cloud Batch API
"""

__author__ = "J Ross Thomson drj@"
__version__ = "0.1.0"

import os
import uuid
import yaml
import sys
import kubernetes.client

from absl import app
from absl import flags
from dynaconf import settings
from google.api_core.operation import Operation
from kubernetes.client import Configuration
from kubernetes.client.rest import ApiException
from pprint import pprint

from tabulate import tabulate
from termcolor import colored
from typing import Iterable
from yaml.loader import SafeLoader

"""
We define multiple command line flags:
"""

FLAGS = flags.FLAGS

flags.DEFINE_string("project_id", None, "Google Cloud Project ID, not name")
flags.DEFINE_boolean("create_job", False, "Creates job, otherwise just prints config.")
flags.DEFINE_boolean("list_jobs", False, "If true, list jobs for config.")
flags.DEFINE_string("delete_job", "", "Job name to delete.")
flags.DEFINE_boolean("debug", False, "If true, print debug info.")
flags.DEFINE_string("args_file", None, "TOML/YAML file with list of container commands")

def get_setting(setting, settings):
  if FLAGS.debug:
    print(f"Getting setting {setting}", file=sys.stderr)
  if setting in settings:
    return(settings[setting])
  else:
    print(f"Setting {setting} not found in settings file. Exiting.", file=sys.stderr)
    exit()

class KubernetesBatchJobs:
  def __init__(self) -> None:

    self.job_prefix = get_setting("job_prefix",settings)

    kubernetes.config.load_kube_config()
    try:
        self.kube_config = Configuration().get_default_copy()
    except AttributeError:
        self.kube_config = Configuration()
        self.kube_config.assert_hostname = False
    Configuration.set_default(self.kube_config)
    self.batch_v1 = kubernetes.client.BatchV1Api(kubernetes.client.ApiClient(self.kube_config))

    self.project_id = get_setting(setting="project_id",settings=settings)

    if os.environ.get('GOOGLE_CLOUD_PROJECT'): 
      self.project_id  = os.environ.get('GOOGLE_CLOUD_PROJECT') 
    if FLAGS.project_id:
      self.project_id = FLAGS.project_id

  def create_job_request(self):

    container1 = self._create_container()
    volumes1 = self._create_volumes()
    mounts1 = self._create_volume_mounts()
    container1.volume_mounts = mounts1
    pod_template1 = self._create_pod_template(container1, volumes1)

    # Create JobSpec
    parallelism = get_setting("parallelism", settings)
    suspend = get_setting("suspend", settings)
    job_spec=kubernetes.client.V1JobSpec(
      template=pod_template1, 
      suspend=suspend, 
      parallelism=parallelism
      )
    completion_mode = get_setting("completion_mode", settings)
    if completion_mode == "Indexed":
      completions = get_setting("completions", settings)
      job_spec.completion_mode = completion_mode
      job_spec.completions = completions

    # Create Job ObjectMetadata
    jobspec_metadata=kubernetes.client.V1ObjectMeta(
      generate_name=self.job_prefix,
    )
    # Create a V1Job object
    job_request = kubernetes.client.V1Job(
      api_version="batch/v1",
      kind="Job",
      spec=job_spec,
      metadata=jobspec_metadata,
    )
    return(job_request)

  def _create_volume_mounts(self):
    # Create Volume Mounts
    # Get volume settings
    mount_settings = get_setting("volume_mount", settings)
    volume_mount1 = kubernetes.client.V1VolumeMount(
      name="gcs-fuse-csi-ephemeral", 
      mount_path=mount_settings["mount_path"]
      )
    return([volume_mount1])

  def _create_volumes(self):
   # Create Volumes
    
    volume_settings = get_setting("volume", settings)

    volume_attributes1 = {"bucketName": volume_settings["bucketName"]}
    volume_source1 = kubernetes.client.V1CSIVolumeSource(
      driver=volume_settings["driver"],
      volume_attributes=volume_attributes1
      )
    volume1 = kubernetes.client.V1Volume(name="gcs-fuse-csi-ephemeral", csi=volume_source1)
    volumes = [volume1]
    return(volumes)

  def _create_container(self):

    # Get container settings
    container_settings = get_setting("container", settings)
    image = get_setting("image_uri", container_settings)

    # Get Job commands
    command = get_setting("command", settings)

    env1 = kubernetes.client.V1EnvVar(
      name = "JOB_NAME",
      value_from=kubernetes.client.V1EnvVarSource(
        field_ref=kubernetes.client.V1ObjectFieldSelector(
          field_path="metadata.name"
        )
      )
    )

    # Get Job Limits
    limits = get_setting("limits", settings)

    # Create container
    
    container = kubernetes.client.V1Container(
      name=self.job_prefix,
      image=image,
      command=command,
      resources=kubernetes.client.V1ResourceRequirements(
          limits=limits,
      ),
      env = [env1],
    )
    return(container)

  def _create_object_metadata(self):
    pass

  def _create_pod_template(self, container1, volumes):
    # Create Pod Template and PodSpec
    service_account_name = get_setting("service_account_name", settings)
    node_selector = get_setting("node_selector", settings)
    pod_annotations = get_setting("pod_annotations", settings)

    podspec_metadata=kubernetes.client.V1ObjectMeta(
      name=self.job_prefix, 
      annotations=pod_annotations
      )
    pod_spec=kubernetes.client.V1PodSpec(
      containers=[container1],
      restart_policy="Never",
      node_selector=node_selector,
      volumes=volumes,
      service_account_name=service_account_name,
      )
    # Create PodTemplateSpec
    pod_template=kubernetes.client.V1PodTemplateSpec(
      metadata=podspec_metadata,
      spec=pod_spec
      )
    return(pod_template)

  #
  # Here is where the jobs is actually created
  #
  def create_job(self, create_request):
  # Create the job in the cluster
    namespace = get_setting("namespace", settings)
    api_response = self.batch_v1.create_namespaced_job(
        namespace=namespace,
        body=create_request,
    )

    #print(api_response.metadata.labels["job-name"],file=sys.stderr)
    print(f"Job {api_response.metadata.labels['job-name']} created. Timestamp='{api_response.metadata.creation_timestamp}'" )

  def delete_job(self, job_name):
    namespace = get_setting("namespace", settings)
    try:
      api_response = self.batch_v1.delete_namespaced_job(job_name, namespace)
      print(api_response,file=sys.stderr)
    except ApiException as e:
      print("Exception when calling BatchV1Api->list_namespaced_job: %s\n" % e)


  def list_jobs(self):
    namespace = get_setting("namespace", settings)
    try:
      api_response = self.core_v1.list_namespaced_job(namespace)
      for item in api_response.items:
        succeeded = item.status.succeeded
        failed = item.status.failed
        completed = item.status.completed_indexes
        print(f"Name: {item.metadata.labels['app']}\tSucceeded: {succeeded}\tFailed: {failed}\tCompleted Index: {completed}", file=sys.stderr)
        # pprint(item)
    except ApiException as e:
      print("Exception when calling BatchV1Api->list_namespaced_job: %s\n" % e)
    headers = ["Job Name", "Succeeded", "Failed", "Completed Index"]
    rows = []
    for item in api_response.items:
      succeeded = item.status.succeeded
      failed = item.status.failed
      completed = item.status.completed_indexes
      rows.append(
        [
          colored(item.metadata.labels['job-name'], 'blue'),
          colored(succeeded, 'green'),
          colored(failed, 'red'),
          colored(completed, 'yellow'),
        ]
      )

    print(tabulate(rows, headers, tablefmt="grid"))

def main(argv):
  """
  """
  jobs = None

  if get_setting("platform", settings) == "gke-autopilot":
    jobs = KubernetesBatchJobs()
  else:
  # Create Cloud Batch jobs object
    print("platform must be set in the settings file. Exiting.")

  # Delete job. JobID must be passed.
  if(FLAGS.delete_job):
    print("Deleting job", file=sys.stderr)
    jobs.delete_job(FLAGS.delete_job)
    exit()

  # Prints list of jobs, in queue, running or complteted.
  if(FLAGS.list_jobs):
    print("Listing jobs", file=sys.stderr)
    jobs.list_jobs()
    exit()

  # Prints config file info
  if FLAGS.debug:
    pass

  if FLAGS.args_file:
    settings.load_file(path=FLAGS.args_file)  # list or `;/,` separated allowed
    for arg in settings.ARGS: 
      print(f"This is the arg: {arg}")
      settings.command = arg
      jobs = KubernetesBatchJobs()
      print(jobs.create_job(jobs.create_job_request()), file=sys.stderr)
    exit()

    
  if FLAGS.create_job:
    # Create the job
    print(jobs.create_job(jobs.create_job_request()), file=sys.stderr)
  else:
    print(jobs.create_job_request(), file=sys.stderr)

if __name__ == "__main__":
    """ This is executed when run from the command line """
    app.run(main)