"""Maintenance-queue Celery tasks.

Currently holds the blocklist cleanup task that retroactively removes
blocklisted tag names from the library. The earlier sync_character_fandoms
task was removed on 2026-04-21 as part of the bare-name refactor.
"""
import logging

from celery import shared_task
from sqlalchemy import text

from app import db
from app.models import Tag

log = logging.getLogger(__name__)


@shared_task(
    name='app.tasks.maintenance.sweep_blocklisted_tag_from_images',
    soft_time_limit=60,
    time_limit=120,
)
def sweep_blocklisted_tag_from_images(name: str) -> dict:
    """Remove a blocklisted tag name from every image that has it attached,
    then delete the Tag row itself.

    Scope is limited to kind='user' tags — that's the kind WD14's general
    category gets materialized as when accepted, which is the vast majority
    of blocklist hits. Character / fandom / artist / series / post / archive
    tags sharing the same name are left alone: those are deliberate, curated
    entities, and removing them silently because of a blocklist text match
    would be destructive.

    Returns a summary dict so the Celery result is introspectable.
    """
    tag = Tag.query.filter_by(kind='user', name=name).first()
    if tag is None:
        log.info("sweep_blocklisted_tag_from_images: no kind='user' tag named %r; nothing to do", name)
        return {'name': name, 'tag_found': False, 'image_tags_deleted': 0, 'tag_deleted': False}

    result = db.session.execute(
        text("DELETE FROM image_tags WHERE tag_id = :tid"),
        {'tid': tag.id},
    )
    rowcount = result.rowcount or 0
    db.session.delete(tag)
    db.session.commit()

    log.info(
        "sweep_blocklisted_tag_from_images: removed %r (tag_id=%d) from %d images",
        name, tag.id, rowcount,
    )
    return {
        'name': name,
        'tag_found': True,
        'image_tags_deleted': rowcount,
        'tag_deleted': True,
    }