# Copyright (c) 2023-present Plane Software, Inc. and contributors
# SPDX-License-Identifier: AGPL-3.0-only
# See the LICENSE file for details.

# Python imports
import os
from datetime import timedelta

# Django imports
from django.conf import settings
from django.utils import timezone
from django.db.models import Q

# Third party imports
from celery import shared_task

# Module imports
from plane.db.models import FileAsset, StoredBlob
from plane.settings.storage import S3Storage
from plane.utils.file_dedup import release_file_asset_blob


def _asset_object_key(asset):
    return str(asset.asset.name or asset.asset)


def _delete_legacy_asset_object(asset, storage):
    object_key = _asset_object_key(asset)
    if not object_key:
        return False

    has_other_reference = FileAsset.all_objects.filter(asset=object_key).exclude(pk=asset.pk).exists()
    if has_other_reference:
        return False

    return storage.delete_files(object_names=[object_key])


def _hard_delete_file_asset(asset, storage=None):
    blob_id = asset.blob_id

    if blob_id:
        release_file_asset_blob(asset)
        StoredBlob.all_objects.filter(
            pk=blob_id,
            ref_count=0,
            status=StoredBlob.Status.ORPHANED,
        ).delete()
    else:
        storage = storage or S3Storage()
        _delete_legacy_asset_object(asset, storage)

    asset.delete(soft=False)


@shared_task
def delete_unuploaded_file_asset():
    """This task deletes unuploaded file assets older than a certain number of days."""
    stale_assets = FileAsset.objects.filter(
        Q(created_at__lt=timezone.now() - timedelta(days=int(os.environ.get("UNUPLOADED_ASSET_DELETE_DAYS", "7"))))
        & Q(is_uploaded=False)
    )
    for asset in stale_assets.iterator():
        release_file_asset_blob(asset, delete_untracked_object=True)
        asset.delete(soft=False)


@shared_task
def delete_expired_file_asset():
    """Hard delete soft-deleted file assets after the restore retention window."""
    days = int(os.environ.get("FILE_ASSET_HARD_DELETE_AFTER_DAYS", settings.HARD_DELETE_AFTER_DAYS))
    cutoff = timezone.now() - timedelta(days=days)
    storage = S3Storage()
    expired_assets = FileAsset.all_objects.filter(deleted_at__lt=cutoff)

    for asset in expired_assets.iterator():
        _hard_delete_file_asset(asset, storage=storage)