from django.db import migrations


def backfill_customer_profiles(apps, schema_editor):
    User = apps.get_model("accounts", "User")
    CustomerProfile = apps.get_model("customers", "CustomerProfile")
    database = schema_editor.connection.alias
    missing_users = (
        User.objects.using(database)
        .filter(account_type="CUSTOMER", customer_profile__isnull=True)
        .values("pk", "first_name", "last_name")
    )
    batch = []
    for user in missing_users.iterator(chunk_size=500):
        batch.append(CustomerProfile(user_id=user["pk"], first_name=user["first_name"][:100], last_name=user["last_name"][:100]))
        if len(batch) == 500:
            CustomerProfile.objects.using(database).bulk_create(batch, ignore_conflicts=True, batch_size=500)
            batch.clear()
    if batch:
        CustomerProfile.objects.using(database).bulk_create(batch, ignore_conflicts=True, batch_size=500)


class Migration(migrations.Migration):
    dependencies = [("customers", "0005_contacteditlog")]
    operations = [migrations.RunPython(backfill_customer_profiles, migrations.RunPython.noop)]