"""Publisher logic."""

import base64
import hashlib

from switchboard_consumer.constants import entity_type, system
from switchboard_consumer.utils.message import create_processing_result


def _get_publisher_unid(name):
    """Generate publisher UNID."""
    name_hash = base64.b64encode(
        hashlib.sha1(name.encode('utf-8')).digest())
    return 'UNID:{}'.format(name_hash.decode('utf-8'))


def get_publisher_processing_results(
        logger, message, tracks, unmapped_tracks_publishers):
    """Get publisher processing results from created tracks."""
    processing_results = []
    for track in tracks:
        track_created_publishers = (track.get('publishing', {}) or {}).get(
            'publisherNames', []) or []
        if not track_created_publishers:
            continue
        isrc = track['isrc']
        unmapped_publishers = unmapped_tracks_publishers.get(isrc, [])
        for unmapped_publisher in unmapped_publishers:
            publisher_name = unmapped_publisher[0]
            unmapped_publisher_ingested = (
                publisher_name in track_created_publishers)
            if unmapped_publisher_ingested:
                switchboard_local_id = unmapped_publisher[1]
                orchard_local_id = {
                    'system': system.ORCHARD,
                    'localId': _get_publisher_unid(publisher_name)
                }
                processing_results.append(create_processing_result(
                    [switchboard_local_id, orchard_local_id],
                    message, entity_type=entity_type.PUBLISHER))
            else:
                logger.error(
                    'Failed to find unmapped publisher',
                    custom_fields={'name': publisher_name, 'isrc': isrc})
    return processing_results