"""持久化任务执行者；获取连接级锁后才恢复或领取任务。"""

from datetime import datetime
from pathlib import Path

from app.core.tplus_db import get_tplus_session_factory, resolve_tplus_settings
from app.core.tplus_lock import TPlusBusyError, sync_lock
from app.repositories import tplus_repository as repository
from app.services.tplus import task_service
from app.services.tplus.relationship_audit import TPlusRelationshipAudit
from app.services.tplus.sync_service import TPlusSyncService


def run_once(session, source_factory=None):
    """返回本轮处理的批次号；忙锁或队列为空时不假称已执行。"""
    try:
        with sync_lock(session):
            task_service.recover_running(session)
            batch = repository.next_queued(session)
            if batch is None:
                session.rollback()
                return None
            batch.status, batch.started_at = "RUNNING", datetime.now()
            session.commit()
            _execute(session, batch, source_factory)
            return batch.batch_no
    except TPlusBusyError:
        session.rollback()
        return None


def _execute(session, batch, source_factory):
    try:
        settings = resolve_tplus_settings(task_service.get_settings())
        if batch.source_database and batch.source_database != settings.t_plus_database:
            raise RuntimeError("任务排队后的源账套配置已改变")
        factory = source_factory or get_tplus_session_factory()
        with factory() as source:
            if batch.sync_mode == "AUDIT":
                root = Path(settings.t_plus_query_dir) if settings.t_plus_query_dir else None
                report = TPlusRelationshipAudit(source, root).run()
                batch.audit_result_json = report
                batch.source_record_count = sum(row["row_count"] for row in report["receipt_kinds"])
                batch.finished_at, batch.status = datetime.now(), "SUCCEEDED"
                if report["relationship_status"] != "OBSERVED":
                    task_service.fail_batch(session, batch, "TYPE_UNRESOLVED")
                else:
                    session.commit()
            else:
                TPlusSyncService(source, session).execute_claimed(batch)
    except BaseException as exc:
        session.rollback()
        task_service.fail_batch(
            session,
            batch,
            "INTERRUPTED"
            if isinstance(exc, (KeyboardInterrupt, SystemExit))
            else "EXECUTION_ERROR",
        )
        if isinstance(exc, (KeyboardInterrupt, SystemExit)):
            raise