import logging
from typing import Optional

from datahub.emitter.mce_builder import make_dataset_urn, make_user_urn
from datahub.emitter.mcp import MetadataChangeProposalWrapper

# read-modify-write requires access to the DataHubGraph (RestEmitter is not enough)
from datahub.ingestion.graph.client import DatahubClientConfig, DataHubGraph

# Imports for metadata model classes
from datahub.metadata.schema_classes import (
    ChangeTypeClass,
    OwnerClass,
    OwnershipClass,
    OwnershipTypeClass,
)

log = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO)


# Inputs -> owner, ownership_type, dataset
owner_to_add = make_user_urn("jdoe")
ownership_type = OwnershipTypeClass.DATAOWNER
dataset_urn = make_dataset_urn(platform="hive", name="realestate_db.sales", env="PROD")

# Some objects to help with conditional pathways later
owner_class_to_add = OwnerClass(owner=owner_to_add, type=ownership_type)
ownership_to_add = OwnershipClass(owners=[owner_class_to_add])


# First we get the current owners
gms_endpoint = "http://localhost:8080"
graph = DataHubGraph(DatahubClientConfig(server=gms_endpoint))


current_owners: Optional[OwnershipClass] = graph.get_aspect_v2(
    entity_urn=dataset_urn,
    aspect="ownership",
    aspect_type=OwnershipClass,
)


need_write = False
if current_owners:
    if (owner_to_add, ownership_type) not in [
        (x.owner, x.type) for x in current_owners.owners
    ]:
        # owners exist, but this owner is not present in the current owners
        current_owners.owners.append(owner_class_to_add)
        need_write = True
else:
    # create a brand new ownership aspect
    current_owners = ownership_to_add
    need_write = True

if need_write:
    event: MetadataChangeProposalWrapper = MetadataChangeProposalWrapper(
        entityType="dataset",
        changeType=ChangeTypeClass.UPSERT,
        entityUrn=dataset_urn,
        aspectName="ownership",
        aspect=current_owners,
    )
    graph.emit(event)
    log.info(
        f"Owner {owner_to_add}, type {ownership_type} added to dataset {dataset_urn}"
    )

else:
    log.info(f"Owner {owner_to_add} already exists, omitting write")