import os
import traceback
import time

import filelock
import newrelic.agent

from . import bug
from . import env
from . import gh
from . import handlers
from . import log
from . import repos
from . import settings
from .errors import RetryableError
from .worker import worker


logger = log.get_logger(__name__)

handler_map = None

_lock = None


@settings.configure
def setup_lock(config):
    global _lock
    if _lock is None:
        path = os.path.join(config["root"], "sync.lock")
        logger.info("Using lockfile at path %s" % path)
        _lock = filelock.FileLock(path)


def with_lock(f):
    global _lock

    def inner(*args, **kwargs):
        if _lock is None:
            setup_lock()
        try:
            with _lock:
                return f(*args, **kwargs)
            # If some other task is waiting on the lock, give it a chance to
            # run before this task completes. That means that manual commands
            # will always  win over celery tasks, which we want
            time.sleep(0.1)
        except Exception:
            logger.error("".join(traceback.format_exc()))
            raise
    inner.__name__ = f.__name__
    inner.__doc__ = f.__doc__
    return inner


@settings.configure
def get_handlers(config):
    global handler_map
    if handler_map is None:
        handler_map = {
            "github": handlers.GitHubHandler(config),
            "push": handlers.PushHandler(config),
            "decision-task": handlers.DecisionTaskHandler(config),
            "try-task": handlers.TryTaskHandler(config),
            "taskgroup": handlers.TaskGroupHandler(config),
            "phabricator": handlers.PhabricatorHandler(config),
        }
    return handler_map


@settings.configure
def setup(config):
    env.set_env(config, None, None)
    gecko_repo = repos.Gecko(config)
    git_gecko = gecko_repo.repo()
    wpt_repo = repos.WebPlatformTests(config)
    git_wpt = wpt_repo.repo()
    gh_wpt = gh.GitHub(config["web-platform-tests"]["github"]["token"],
                       config["web-platform-tests"]["repo"]["url"])

    bz = bug.Bugzilla(config)

    env.set_env(config, bz, gh_wpt)
    logger.info("Gecko repository: %s" % git_gecko.working_dir)
    logger.info("wpt repository: %s" % git_wpt.working_dir)
    logger.info("Tasks enabled: %s" % (", ".join(list(config["sync"]["enabled"].keys()))))

    return git_gecko, git_wpt


@worker.task(bind=True, max_retries=6, retry_backoff=60, retry_backoff_max=3840)
@with_lock
def handle(self, task, body):
    handlers = get_handlers()
    if task in handlers:
        logger.info("Running task %s" % task)
        newrelic.agent.add_custom_parameter("task", task)
        git_gecko, git_wpt = setup()
        try:
            handlers[task](git_gecko, git_wpt, body)
        except RetryableError as e:
            self.retry(exc=e.wrapped)
        except Exception:
            logger.error(body)
            logger.error("".join(traceback.format_exc()))
            raise
    else:
        logger.error("No handler for %s" % task)


@worker.task(bind=True, max_retries=6, retry_backoff=60, retry_backoff_max=3840)
@with_lock
@settings.configure
def land(self, config):
    git_gecko, git_wpt = setup()
    try:
        handlers.LandingHandler(config)(git_gecko, git_wpt, {})
    except RetryableError as e:
        self.retry(exc=e.wrapped)


@worker.task
@with_lock
@settings.configure
def cleanup(config):
    git_gecko, git_wpt = setup()
    handlers.CleanupHandler(config)(git_gecko, git_wpt, {})


@worker.task
@with_lock
@settings.configure
def retrigger(config):
    git_gecko, git_wpt = setup()
    handlers.RetriggerHandler(config)(git_gecko, git_wpt, {})


@worker.task
@with_lock
@settings.configure
def update_bugs(config):
    git_gecko, git_wpt = setup()
    handlers.BugUpdateHandler(config)(git_gecko, git_wpt, {})