import datetime

from aws.base import Base


class Function(Base):
    def __init__(self, client, func):
        super().__init__(client)
        self.name = func.get("FunctionName")
        self.arn = func.get("FunctionArn")
        self.runtime = func.get("Runtime")

    def get_number_of_invocations(self, client) -> float:
        today = datetime.datetime.today()
        end = today.replace(day=1)
        start = end - datetime.timedelta(days=30)
        responce = client.get_metric_statistics(
            Namespace='AWS/Lambda',
            MetricName='Invocations',
            Dimensions=[
                {
                    'Name': 'FunctionName',
                    'Value': self.name
                },
            ],
            Statistics=['Sum'],
            Unit='Count',
            StartTime=start,
            EndTime=end,
            Period=86400 * 30 # 30 days
        )

        datapoints = responce.get('Datapoints', [])
        if len(datapoints) == 0:
            return 0

        return datapoints[0].get('Sum', 0)