# -*- coding: utf-8 -*-
#
import os
import datetime
import sys

from django.conf import settings
from django.utils import timezone
from django.core.cache import cache
from django.db import transaction
from celery import subtask
from celery.signals import worker_ready, worker_shutdown, task_prerun, \
    task_postrun, after_task_publish
from django_celery_beat.models import PeriodicTask

from common.utils import get_logger, TeeObj, get_object_or_none
from common.const import celery_task_pre_key
from .utils import get_after_app_ready_tasks, get_after_app_shutdown_clean_tasks
from ..models import CeleryTask

logger = get_logger(__file__)


@worker_ready.connect
def on_app_ready(sender=None, headers=None, body=None, **kwargs):
    if cache.get("CELERY_APP_READY", 0) == 1:
        return
    cache.set("CELERY_APP_READY", 1, 10)
    logger.debug("App ready signal recv")
    tasks = get_after_app_ready_tasks()
    logger.debug("Start need start task: [{}]".format(
        ", ".join(tasks))
    )
    for task in tasks:
        subtask(task).delay()


@worker_shutdown.connect
def after_app_shutdown(sender=None, headers=None, body=None, **kwargs):
    if cache.get("CELERY_APP_SHUTDOWN", 0) == 1:
        return
    cache.set("CELERY_APP_SHUTDOWN", 1, 10)
    tasks = get_after_app_shutdown_clean_tasks()
    logger.debug("App shutdown signal recv")
    logger.debug("Clean need cleaned period tasks: [{}]".format(
        ', '.join(tasks))
    )
    PeriodicTask.objects.filter(name__in=tasks).delete()


@after_task_publish.connect
def after_task_publish_signal_handler(sender, headers=None, **kwargs):
    CeleryTask.objects.create(
        id=headers["id"], status=CeleryTask.WAITING, name=headers["task"]
    )


@task_prerun.connect
def pre_run_task_signal_handler(sender, task_id=None, task=None, **kwargs):
    t = get_object_or_none(CeleryTask, id=task_id)
    if t is None:
        logger.warn("Not get the task: {}".format(task_id))
        return
    now = datetime.datetime.now().strftime("%Y-%m-%d")
    log_path = os.path.join(now, task_id + '.log')
    full_path = os.path.join(CeleryTask.LOG_DIR, log_path)

    if not os.path.exists(os.path.dirname(full_path)):
        os.makedirs(os.path.dirname(full_path))
    with transaction.atomic():
        t.date_start = timezone.now()
        t.status = CeleryTask.RUNNING
        t.log_path = log_path
        t.save()
    f = open(full_path, 'w')
    tee = TeeObj(f)
    sys.stdout = tee
    task.log_f = tee


@task_postrun.connect
def post_run_task_signal_handler(sender, task_id=None, task=None, **kwargs):
    t = get_object_or_none(CeleryTask, id=task_id)
    if t is None:
        logger.warn("Not get the task: {}".format(task_id))
        return
    with transaction.atomic():
        t.status = CeleryTask.FINISHED
        t.date_finished = timezone.now()
        t.save()
    task.log_f.flush()
    sys.stdout = task.log_f.origin_stdout
    task.log_f.close()