from .task import Task
from aws.base import Base


class Service(Base):
    def __init__(self, client, cluster_arn, service_arn, launch_type='FARGATE'):
        super().__init__(client)
        self.cluster_arn = cluster_arn
        self.service_arn = service_arn
        self.launch_type = launch_type
        self.resource_id = f'service/{cluster_arn.split("/")[-1]}/{service_arn.split("/")[-1]}'

    def get_service_name(self) -> str:
        return self.service_arn.split('/')[-1]

    def get_tasks(self) -> list:
        client = self.get_client()
        paginator = client.get_paginator('list_tasks')
        page_iterator = paginator.paginate(cluster=self.cluster_arn,
                                           serviceName=self.service_arn,
                                           launchType=self.launch_type)
        return [Task(client, self.cluster_arn, item) for sublist in
                page_iterator for item in
                sublist.get('taskArns', [])]

    def get_desire_count(self) -> int:
        result = self.describe()

        services = result.get('services')

        if len(services) == 0:
            return 0

        return services[0].get('desireCount', 0)

    def get_load_balancers(self) -> list:
        result = self.describe()

        services = result.get('services', [])

        if len(services) == 0:
            return []

        return services[0].get('loadBalancers', [])

    def get_min_count(self, client) -> int:
        result = client.describe_scalable_targets(
            ResourceIds=[self.resource_id],
            ScalableDimension='ecs:service:DesiredCount',
            ServiceNamespace='ecs',
        )
        if len(result.get('ScalableTargets', [])) > 0:
            scalable_targets = result['ScalableTargets'][0]
            return scalable_targets['MinCapacity']

        return 0

    def get_max_count(self, client) -> int:
        result = client.describe_scalable_targets(
            ResourceIds=[self.resource_id],
            ScalableDimension='ecs:service:DesiredCount',
            ServiceNamespace='ecs',
        )
        if len(result.get('ScalableTargets', [])) > 0:
            scalable_targets = result['ScalableTargets'][0]
            return scalable_targets['MaxCapacity']

        return 0

    def describe(self):
        return self.get_client().describe_services(cluster=self.cluster_arn,
                                                   services=[self.service_arn])