"""Avro serializer helper."""

from confluent_kafka.schema_registry import SchemaRegistryClient
from confluent_kafka.schema_registry.avro import AvroSerializer as ConfluentAvroSerializer

from kafka_utils.producer.helpers import get_context


def build_avro_serializer(
    schema_registry_url,
    topic_name,
    schema_version,
    context='value',
    config=None
):
    """Build an avro serializer."""
    schema_registry_client = SchemaRegistryClient({'url': schema_registry_url})
    serializer_context = get_context(context)
    schema_subject = f'{topic_name}-{serializer_context}'
    schema = schema_registry_client.get_version(schema_subject, schema_version)
    schema_str = schema.schema.schema_str
    serializer_config = {'auto.register.schemas': False}
    if config:
        serializer_config.update(**config)
    return ConfluentAvroSerializer(schema_registry_client, schema_str, conf=serializer_config)