from sqlalchemy.event import listen

import edbob

import rattail

log = logging.getLogger(__name__)

def before_flush(session, flush_context, instances):

    """

    Listens for session flush events.  This function is responsible for adding

    stub records to the 'changes' table, which will in turn be used by the

    database synchronizer.

    """

    def record_change(instance, deleted=False):

        # No need to record changes for Change. :)

        if isinstance(instance, rattail.Change):

            return

        # Ignore instances which don't use UUID.

        if not hasattr(instance, 'uuid'):

            return

        # Provide an UUID value, if necessary.

        if not instance.uuid:

            instance.uuid = edbob.get_uuid()

        # Record the change.

        change = session.query(rattail.Change).get(

            (instance.__class__.__name__, instance.uuid))

        if not change:

            change = rattail.Change(

                class_name=instance.__class__.__name__,

                uuid=instance.uuid)

            session.add(change)

        change.deleted = deleted

        log.debug("before_flush: recorded change: %s" % repr(change))

    for instance in session.deleted:

        log.debug("before_flush: deleted instance: %s" % repr(instance))

        record_change(instance, deleted=True)

    for instance in session.new:

from sqlalchemy import types

from sqlalchemy import and_

from sqlalchemy.orm import relationship, object_session

from sqlalchemy.ext.associationproxy import association_proxy

from sqlalchemy.ext.orderinglist import ordering_list

import edbob

from edbob.db.model import Base, uuid_column

from edbob.db.extensions.contact import Person, EmailAddress, PhoneNumber

from edbob.exceptions import LoadSpecError

from edbob.sqlalchemy import getset_factory

from rattail import sil

from rattail import batches

from rattail.gpc import GPCType

__all__ = ['Change', 'Store', 'StoreEmailAddress', 'StorePhoneNumber',

           'Department', 'Subdepartment', 'Brand', 'Category', 'Vendor',

           'VendorContact', 'VendorPhoneNumber', 'VendorEmailAddress',

           'Product', 'ProductCost', 'ProductPrice', 'Customer',

           'CustomerEmailAddress', 'CustomerPhoneNumber', 'CustomerGroup',

           'CustomerGroupAssignment', 'CustomerPerson', 'Employee',

           'EmployeeEmailAddress', 'EmployeePhoneNumber',

log = logging.getLogger(__name__)

class Change(Base):

    """

    Represents a changed (or deleted) record, which is pending synchronization

    to another database.

    """

    __tablename__ = 'changes'

    class_name = Column(String(25), primary_key=True)

    uuid = Column(String(32), primary_key=True)

    deleted = Column(Boolean)

    def __repr__(self):

        status = 'deleted' if self.deleted else 'new/changed'

        return "<Change: %s, %s, %s>" % (self.class_name, self.uuid, status)

class BatchColumn(Base):

    """