from typing import Dict, Generator, List

from notification_service.entities import NotificationType

from datadog.dogstatsd.base import statsd


def chunks(lst: List, elements: int) -> Generator:
    """Yield successive n-sized chunks from lst."""
    for i in range(0, len(lst), elements):
        yield lst[i:i + elements]


def send_metric_by_dimension(msg: Dict) -> None:
    content_keys = msg['data']['content'].keys()
    if NotificationType.TRACK.value in content_keys:
        notification_type = NotificationType.TRACK.value
    elif NotificationType.PLAYLIST.value in content_keys:
        notification_type = NotificationType.PLAYLIST.value
    else:
        raise Exception('Unsupported notification_type.'
                        f'Existing keys in json - {content_keys}')
    dsp = msg['meta']['dsp']
    event_type = msg['meta']['event_type']
    statsd.increment(
        'notification-service.sent_notifications',
        tags=[
            f'notification_type:{notification_type}',
            f'dsp:{dsp}',
            f'event_type:{event_type}',
        ],
    )