from django.db import migrations


def merge_legacy_accounting_unit(apps, schema_editor):
    Unit = apps.get_model("staff", "OrganizationalUnit")
    Membership = apps.get_model("staff", "UnitMembership")
    StaffProfile = apps.get_model("staff", "StaffProfile")
    TicketCategory = apps.get_model("tickets", "TicketCategory")
    Ticket = apps.get_model("tickets", "Ticket")
    GroupDispatch = apps.get_model("tickets", "GroupDispatch")
    ContactGroup = apps.get_model("customers", "ContactGroup")
    CustomerProfile = apps.get_model("customers", "CustomerProfile")
    SMSTemplate = apps.get_model("notifications", "SMSTemplate")
    TicketMagicLink = apps.get_model("accounts", "TicketMagicLink")

    legacy = Unit.objects.filter(slug="accounting").first()
    canonical = Unit.objects.filter(slug="finance").first()
    if legacy is None:
        return
    if canonical is None:
        legacy.slug = "finance"
        legacy.name = "مالی / حسابداری"
        legacy.description = "واحد مالی و حسابداری (یک مفهوم سازمانی)"
        legacy.is_active = True
        legacy.accepts_external_tickets = True
        legacy.show_in_customer_form = True
        legacy.save()
        return

    canonical.permissions.add(*legacy.permissions.all())
    TicketCategory.objects.filter(unit=legacy).update(unit=canonical)
    Ticket.objects.filter(owning_unit=legacy).update(owning_unit=canonical)
    Ticket.objects.filter(assigned_unit=legacy).update(assigned_unit=canonical)
    GroupDispatch.objects.filter(unit=legacy).update(unit=canonical)
    TicketMagicLink.objects.filter(created_unit=legacy).update(created_unit=canonical)
    StaffProfile.objects.filter(primary_unit=legacy).update(primary_unit=canonical)

    for membership in Membership.objects.filter(unit=legacy):
        existing = Membership.objects.filter(user_id=membership.user_id, unit=canonical).first()
        if existing is None:
            membership.unit = canonical
            membership.save(update_fields=["unit", "updated_at"])
            continue
        existing.permissions.add(*membership.permissions.all())
        existing.is_active = existing.is_active or membership.is_active
        existing.is_primary = existing.is_primary or membership.is_primary
        if membership.ticket_scope == "UNIT":
            existing.ticket_scope = "UNIT"
        existing.save(update_fields=["is_active", "is_primary", "ticket_scope", "updated_at"])
        membership.delete()

    for group in ContactGroup.objects.filter(unit=legacy):
        existing = ContactGroup.objects.filter(unit=canonical, name=group.name).first()
        if existing is None:
            group.unit = canonical
            group.save(update_fields=["unit", "updated_at"])
            continue
        for profile in CustomerProfile.objects.filter(groups=group):
            profile.groups.add(existing)
        GroupDispatch.objects.filter(contact_group=group).update(contact_group=existing)
        group.delete()

    for template in SMSTemplate.objects.filter(unit=legacy):
        if SMSTemplate.objects.filter(unit=canonical, event_type=template.event_type).exists():
            template.delete()
        else:
            template.unit = canonical
            template.save(update_fields=["unit", "updated_at"])

    legacy.delete()


class Migration(migrations.Migration):
    dependencies = [("tickets", "0012_groupdispatch_operation_permissions_and_seed_org")]
    operations = [migrations.RunPython(merge_legacy_accounting_unit, migrations.RunPython.noop)]