import logging
from datetime import UTC, datetime

import click
from redis.exceptions import LockError

import app
from configs import dify_config
from extensions.ext_redis import redis_client
from services.retention.workflow_run.clear_free_plan_expired_workflow_run_logs import WorkflowRunCleanup

logger = logging.getLogger(__name__)


@app.celery.task(queue="retention")
def clean_workflow_runs_task() -> None:
    """
    Scheduled cleanup for workflow runs and related records (sandbox tenants only).
    """
    click.echo(
        click.style(
            (
                "Scheduled workflow run cleanup starting: "
                f"cutoff={dify_config.SANDBOX_EXPIRED_RECORDS_RETENTION_DAYS} days, "
                f"batch={dify_config.SANDBOX_EXPIRED_RECORDS_CLEAN_BATCH_SIZE}"
            ),
            fg="green",
        )
    )

    start_time = datetime.now(UTC)

    try:
        # lock the task to avoid concurrent execution in case of the future data volume growth
        with redis_client.lock(
            "retention:clean_workflow_runs_task",
            timeout=dify_config.SANDBOX_EXPIRED_RECORDS_CLEAN_TASK_LOCK_TTL,
            blocking=False,
        ):
            WorkflowRunCleanup(
                days=dify_config.SANDBOX_EXPIRED_RECORDS_RETENTION_DAYS,
                batch_size=dify_config.SANDBOX_EXPIRED_RECORDS_CLEAN_BATCH_SIZE,
                start_from=None,
                end_before=None,
            ).run()

        end_time = datetime.now(UTC)
        elapsed = end_time - start_time
        click.echo(
            click.style(
                f"Scheduled workflow run cleanup finished. start={start_time.isoformat()} "
                f"end={end_time.isoformat()} duration={elapsed}",
                fg="green",
            )
        )
    except LockError:
        end_time = datetime.now(UTC)
        elapsed = end_time - start_time
        logger.exception("clean_workflow_runs_task: acquire task lock failed, skip current execution")
        click.echo(
            click.style(
                f"Scheduled workflow run cleanup skipped (lock already held). "
                f"start={start_time.isoformat()} end={end_time.isoformat()} duration={elapsed}",
                fg="yellow",
            )
        )
        raise
    except Exception as e:
        end_time = datetime.now(UTC)
        elapsed = end_time - start_time
        logger.exception("clean_workflow_runs_task failed")
        click.echo(
            click.style(
                f"Scheduled workflow run cleanup failed. start={start_time.isoformat()} "
                f"end={end_time.isoformat()} duration={elapsed} - {str(e)}",
                fg="red",
            )
        )
        raise