"""part app specification"""

import logging

from django.apps import AppConfig
from django.db.utils import OperationalError, ProgrammingError

from InvenTree.ready import canAppAccessDatabase, isImportingData

logger = logging.getLogger("inventree")


class PartConfig(AppConfig):
    """Config class for the 'part' app"""
    name = 'part'

    def ready(self):
        """This function is called whenever the Part app is loaded."""
        if canAppAccessDatabase():
            self.update_trackable_status()
            self.reset_part_pricing_flags()

    def update_trackable_status(self):
        """Check for any instances where a trackable part is used in the BOM for a non-trackable part.

        In such a case, force the top-level part to be trackable too.
        """
        from .models import BomItem

        try:
            items = BomItem.objects.filter(part__trackable=False, sub_part__trackable=True)

            for item in items:
                logger.info(f"Marking part '{item.part.name}' as trackable")
                item.part.trackable = True
                item.part.clean()
                item.part.save()
        except (OperationalError, ProgrammingError):  # pragma: no cover
            # Exception if the database has not been migrated yet
            pass

    def reset_part_pricing_flags(self):
        """Performed on startup, to ensure that all pricing objects are in a "good" state.

        Prevents issues with state machine if the server is restarted mid-update
        """

        from .models import PartPricing

        if isImportingData():
            return

        items = PartPricing.objects.filter(scheduled_for_update=True)

        if items.count() > 0:
            # Find any pricing objects which have the 'scheduled_for_update' flag set
            print(f"Resetting update flags for {items.count()} pricing objects...")

            for pricing in items:
                pricing.scheduled_for_update = False
                pricing.save()