import datetime
import os
import sys
from subprocess import check_call

import babis
import waffle
from apscheduler.schedulers.blocking import BlockingScheduler
from django.conf import settings
from django.utils import timezone

MANAGE = os.path.join(settings.ROOT, "manage.py")
schedule = BlockingScheduler()


def call_command(command):
    check_call("python {0} {1}".format(MANAGE, command), shell=True)


class scheduled_job(object):
    """Decorator for scheduled jobs. Takes same args as apscheduler.schedule_job."""

    def __init__(self, *args, **kwargs):
        self.args = args
        self.kwargs = kwargs
        self.skip = self.kwargs.pop("skip", False)

    def __call__(self, fn):
        self.name = fn.__name__
        if self.skip:
            self.log("Skipped, not registered.")
            return None
        self.callback = fn
        schedule.add_job(self.run, id=self.name, *self.args, **self.kwargs)
        self.log("Registered.")
        return self.run

    def run(self):
        self.log("starting")
        try:
            self.callback()
        except Exception as e:
            self.log("CRASHED: {}".format(e))
            raise
        else:
            self.log("finished successfully")

    def log(self, message):
        msg = "[{}] Clock job {}@{}: {}".format(
            datetime.datetime.utcnow(), self.name, settings.PLATFORM_NAME, message
        )
        print(msg, file=sys.stderr)


# Every 10 minutes.
@scheduled_job("cron", month="*", day="*", hour="*", minute="*/10", max_instances=1, coalesce=True)
@babis.decorator(ping_after=settings.DMS_ENQUEUE_LAG_MONITOR_TASK)
def job_enqueue_lag_monitor_task():
    call_command("enqueue_lag_monitor_task")


# Every hour.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*",
    minute="30",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_SEND_WELCOME_EMAILS)
def job_send_welcome_emails():
    call_command("send_welcome_emails")


# Every 15 minutes, retry any failed emails.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*",
    minute="*/15",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
def job_send_queued_mail():
    call_command("send_queued_mail_async")


# Every week, cleanup any expired emails.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="12",
    minute="0",
    day_of_week=0,
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
def job_cleanup_mail():
    call_command("cleanup_mail")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*",
    minute="45",
    max_instances=1,
    coalesce=True,
    # only run on readonly clusters, where no signals will be triggered:
    skip=(not settings.READ_ONLY),
)
@babis.decorator(ping_after=settings.DMS_REINDEX_ES)
def job_reindex_es():
    # Index items newer than 90 minutes old in ES
    after = (timezone.now() - datetime.timedelta(minutes=90)).isoformat()
    call_command("es_reindex --updated-after {}".format(after))


# Every 6 hours.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*/6",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_UPDATE_PRODUCT_DETAILS)
def job_update_product_details():
    call_command("update_product_details")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*/6",
    minute="20",
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_GENERATE_MISSING_SHARE_LINKS)
def job_generate_missing_share_links():
    call_command("generate_missing_share_links")


# Once per day.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="00",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_REBUILD_KB)
def job_rebuild_kb():
    call_command("rebuild_kb")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="00",
    minute="42",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_UPDATE_TOP_CONTRIBUTORS)
def job_update_top_contributors():
    call_command("update_top_contributors")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="01",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_UPDATE_L10N_COVERAGE_METRICS)
def job_update_l10n_coverage_metrics():
    call_command("update_l10n_coverage_metrics")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="01",
    minute="11",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_REPORT_EMPLOYEE_ANSWERS)
def job_report_employee_answers():
    call_command("report_employee_answers")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="01",
    minute="40",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_UPDATE_WEEKLY_VOTES)
def job_update_weekly_votes():
    call_command("update_weekly_votes")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="03",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_UPDATE_CONTRIBUTOR_METRICS)
def job_update_contributor_metrics():
    call_command("update_contributor_metrics")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="04",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_AUTO_ARCHIVE_OLD_QUESTIONS)
def job_auto_archive_old_questions():
    call_command("auto_archive_old_questions")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="10",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_UPDATE_L10N_METRIC)
def job_update_l10n_metric():
    call_command("update_l10n_metric")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="16",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_RELOAD_WIKI_TRAFFIC_STATS)
def job_reload_wiki_traffic_stats():
    call_command("reload_wiki_traffic_stats")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="21",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_CACHE_MOST_UNHELPFUL_KB_ARTICLES)
def job_cache_most_unhelpful_kb_articles():
    call_command("cache_most_unhelpful_kb_articles")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="23",
    minute="00",
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_RELOAD_QUESTION_TRAFFIC_STATS)
def job_reload_question_traffic_stats():
    call_command("reload_question_traffic_stats")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="04",
    minute="00",
    day_of_week=5,
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or settings.STAGE),
)
@babis.decorator(ping_after=settings.DMS_SEND_WEEKLY_READY_FOR_REVIEW_DIGEST)
def job_send_weekly_ready_for_review_digest():
    call_command("send_weekly_ready_for_review_digest")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="00",
    minute="00",
    day_of_week=0,
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_FIX_CURRENT_REVISIONS)
def job_fix_current_revisions():
    call_command("fix_current_revisions")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="00",
    minute="30",
    day_of_week=1,
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_COHORT_ANALYSIS)
def job_cohort_analysis():
    call_command("cohort_analysis")


# Once per month
@scheduled_job(
    "cron",
    month="*",
    day="1",
    hour="00",
    minute="30",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_UPDATE_L10N_CONTRIBUTOR_METRICS)
def job_update_l10n_contributor_metrics():
    call_command("update_l10n_contributor_metrics")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="02",
    minute="00",
    day_of_week=0,
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_CLEANUP_OLD_ACCOUNT_EVENTS)
def job_cleanup_old_account_events():
    call_command("cleanup_old_account_events")


@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="03",
    minute="00",
    day_of_week=0,
    max_instances=1,
    coalesce=True,
    skip=(settings.READ_ONLY or not waffle.switch_is_active("cleanup-expired-users")),
)
@babis.decorator(ping_after=settings.DMS_CLEANUP_EXPIRED_USERS)
def job_cleanup_expired_users():
    call_command("cleanup_expired_users")


# Every 4 hours, 15 minutes after the hour.
@scheduled_job(
    "cron",
    month="*",
    day="*",
    hour="*/4",
    minute="15",
    max_instances=1,
    coalesce=True,
    skip=settings.READ_ONLY,
)
@babis.decorator(ping_after=settings.DMS_REPROCESS_FAILED_ACCOUNT_EVENTS)
def job_reprocess_failed_account_events():
    """
    Re-process any account events created within the past 24 hours that remain
    in the unprocessed state. Kicks off a Celery task that does the following:
        * Gathers all unprocessed account events created within the past 24 hours.
        * Kicks off a separate Celery task to reprocess each one.
    """
    call_command("reprocess_failed_account_events --within-hours 24")


def run():
    try:
        schedule.start()
    except (KeyboardInterrupt, SystemExit):
        pass