"""Read-only option metadata for the staff dispatch composer."""

from django.db.models import Count, Q

from .models import GroupDispatch, TicketCategory
from .policies import DispatchPolicy


def dispatch_form_options(user, units, groups):
    """Expose only permitted units; recipient counts follow the sending service."""
    units = list(units)
    eligible = (
        Q(contacts__user__is_active=True, contacts__user__mobile__isnull=False)
        & ~Q(contacts__user__mobile="")
    )
    return {
        "units": [
            {
                "id": unit.pk,
                "name": unit.name,
                "operations": [
                    kind for kind in GroupDispatch.OperationType.values
                    if DispatchPolicy.can_create(user, unit, kind)
                ],
            }
            for unit in units
        ],
        "groups": list(groups.annotate(recipient_count=Count("contacts", filter=eligible)).values(
            "id", "name", "unit_id", "recipient_count",
        )),
        "categories": list(TicketCategory.objects.filter(
            Q(unit_id__in=[unit.pk for unit in units]) | Q(unit__isnull=True),
            is_active=True,
        ).order_by("title").values("id", "title", "unit_id")),
    }