# -*- coding: utf-8 -*-
# !/usr/bin/env python
"""
主要是投掷于celery的一系列任务
~~~~~~~~~
"""
import datetime
import logging

from celery import Task
from typing import Optional

logger = logging.getLogger(__name__)


class TraceTask(Task):
    abstract = True

    def __init__(self):
        self.offline_task = False

    def on_success(self, retval, task_id, args, kwargs):
        """Success handler.

        Run by the worker if the task executes successfully.

        :param retval: The return value of the task.
        :param task_id: Unique id of the executed task.
        :param args: Original arguments for the executed task.
        :param kwargs: Original keyword arguments for the executed task.

        The return value of this handler is ignored.

        """
        logger.debug('on_success. task_id = {}, retval = {}'.format(task_id, retval))

    def on_retry(self, exc, task_id, args, kwargs, einfo):
        """Retry handler.

        This is run by the worker when the task is to be retried.

        :param exc: The exception sent to :meth:`retry`.
        :param task_id: Unique id of the retried task.
        :param args: Original arguments for the retried task.
        :param kwargs: Original keyword arguments for the retried task.

        :keyword einfo: :class:`~billiard.einfo.ExceptionInfo`
                        instance, containing the traceback.

        The return value of this handler is ignored.

        """
        logger.debug('on_retry. task_id = {}'.format(task_id))

    def on_failure(self, exc, task_id, args, kwargs, einfo):
        """Error handler.

        This is run by the worker when the task fails.

        :param exc: The exception raised by the task.
        :param task_id: Unique id of the failed task.
        :param args: Original arguments for the task that failed.
        :param kwargs: Original keyword arguments for the task
                       that failed.

        :keyword einfo: :class:`~billiard.einfo.ExceptionInfo`
                        instance, containing the traceback.

        The return value of this handler is ignored.

        """
        logger.error(
            'on_failure. exc = {}, task_id = {}, args = {}, kwargs = {}, einfo = {}'.format(
                exc, task_id, args, kwargs, einfo))

    def after_return(self, status, retval, task_id, args, kwargs, einfo):
        """Handler called after the task returns.

        :param status: Current task state.
        :param retval: Task return value/exception.
        :param task_id: Unique id of the task.
        :param args: Original arguments for the task that failed.
        :param kwargs: Original keyword arguments for the task
                       that failed.

        :keyword einfo: :class:`~billiard.einfo.ExceptionInfo`
                        instance, containing the traceback (if any).

        The return value of this handler is ignored.

        """
        logger.debug(
            'after_return. task_id = {}, status = {}, args = {}, kwargs = {}, exception = {}, retval = {}, headers = {}'.format(
                task_id, status, str(args), str(kwargs), str(einfo), str(retval), self.request.headers))

        if 'offline_task_id' in self.request.headers and self.request.headers['offline_task_id']:
            from apps.web.core.models import OfflineTask

            offline_task_id = str(self.request.headers['offline_task_id'])

            offline_task = OfflineTask.objects(id = offline_task_id).first()  # type: Optional[OfflineTask]
            if not offline_task:
                logger.error('no such task id({})'.format(offline_task_id))
            else:
                updated = offline_task.update(celery_task_id = task_id,
                                              status = status,
                                              finishedTime = datetime.datetime.now())
                if not updated:
                    logger.error(u'update offline task(id=%s) failed.' % (offline_task_id,))
                else:
                    logger.debug(u'update offline task(id=%s) success.' % (offline_task_id,))