"""This module is in charge of managing all the trigger services.

Trigger services are the components responsible managing the execution of Augs.

Each trigger service must export the following methods:
- __init__(self, output) - Construct the object, receives a point to the Output object.
- remove_aug(self, aug_id) - Remove an Aug by it's id.
- clear_augs(self) - Remove all Augs.

Services are loaded from the services packages.
"""
from six import itervalues

from .services import BdbLocationService, ImportService, LoggingLocationService, HttpServerService, \
    ExceptionCapturingLocationService

from .exceptions import RookServiceMissing

from .logger import logger


class TriggerServices(object):
    """This class implements all the module's functionality."""

    def __init__(self):
        """Load and initialize all the trigger services."""
        self._services = dict()

    def get_service(self, name):
        """Return the trigger service by it's name."""
        try:
            return self._services[name]
        except KeyError:
            raise RookServiceMissing(name)

    def remove_aug(self, aug_id):
        """Remove an Aug from all services by it's id."""
        for service in itervalues(self._services):
            try:
                service.remove_aug(aug_id)
            except Exception:
                logger.exception("Error when removing aug")

    def clear_augs(self):
        """Remove all Augs from all services."""

        for service in itervalues(self._services):
            service.clear_augs()

    def start(self):
        self._load_services()

    def close(self):
        for service in itervalues(self._services):
            service.close()

        self._services = {}

    def pre_fork(self):
        for service in itervalues(self._services):
            service.pre_fork()

    def post_fork(self):
        for service in itervalues(self._services):
            service.post_fork()

    def _load_services(self):
        try:
            self._services[BdbLocationService.NAME] = BdbLocationService()
            self._services[ImportService.NAME] = ImportService(self._services[BdbLocationService.NAME])
        except:  # lgtm[py/catch-base-exception]
            logger.exception("Error starting location based services")

        try:
            self._services[LoggingLocationService.NAME] = LoggingLocationService()
        except:  # lgtm[py/catch-base-exception]
            logger.exception("Error starting log handler services")

        try:
            self._services[HttpServerService.NAME] = HttpServerService()
        except:  # lgtm[py/catch-base-exception]
            logger.exception("Error starting http server services")

        try:
            self._services[ExceptionCapturingLocationService.NAME] = ExceptionCapturingLocationService()
        except:  # lgtm[py/catch-base-exception]
            logger.exception("Error starting exception capturing handler services")