"""Datadog Connector."""

import time
from contextlib import contextmanager

from datadog import api, initialize

from grass import config


@contextmanager
def datadog_connection(api_key=None, app_key=None):
    """Context manager for datadog connection objects.

    Yields:
        datadog.api: connection to datadog api
    """
    if not api_key:
        api_key = config.DD_API_KEY

    if not app_key:
        app_key = config.DD_APP_KEY

    initialize(api_key=api_key, app_key=app_key)

    yield api


def key(metric_key: str):
    """Create a namespaced key.

    Args:
        metric_key (str): the metric key.
    Returns:
        str: the key.

    """
    return f'ows.grass.{metric_key}'


def send_timer(metric, delta_ms, logger=None):
    """Send a timer (latency value in ms) to Datadog."""

    if not config.SEND_METRICS_TO_DD_ENABLED:
        return

    assert metric.startswith('ows.grass.')

    now = int(time.time())
    with datadog_connection() as datadog:
        try:
            datadog.Metric.send(
                metric=metric,
                points=[(now, delta_ms)],
                type='gauge',
                tags=[
                    f'environment:{config.environment}',
                    f'service_name:{config.SERVICE_NAME}',
                    'unit:ms',
                ],
            )
        except Exception as e:
            if logger:
                logger.error(f'Datadog metric send failure. {e}')


def publish_metric(metric: str, count: int = 1, logger=None):
    """Publish a metric to DataDog."""
    if not config.SEND_METRICS_TO_DD_ENABLED:
        return

    assert metric.startswith('ows.grass.')

    now = int(time.time())
    with datadog_connection() as datadog:
        try:
            datadog.Metric.send(
                metric=metric,
                points=[(now, count)],
                type='count',
                tags=[
                    f'environment:{config.environment}',
                    f'service_name:{config.SERVICE_NAME}',
                ],
            )
        except Exception as e:
            if logger:
                logger.warning(f'Datadog metric send failure. {e}')