from __future__ import annotations

from datetime import datetime
from typing import Protocol

from sqlalchemy.orm import Session

from govoplan_core.core.events import (
    EventActorRef,
    EventObjectRef,
    EventTenantRef,
    PlatformEvent,
    emit_platform_event,
)


class AssignmentEventSource(Protocol):
    id: str
    tenant_id: str
    identity_id: str
    account_id: str | None
    function_id: str
    organization_unit_id: str
    applies_to_subunits: bool
    source: str
    delegated_from_assignment_id: str | None
    acting_for_account_id: str | None
    valid_from: datetime | None
    valid_until: datetime | None
    is_active: bool


def emit_assignment_event(
    session: Session,
    item: AssignmentEventSource,
    *,
    event_type: str,
    actor_type: str,
    actor_id: str | None = None,
    occurred_at: datetime | None = None,
) -> None:
    event_options = {"occurred_at": occurred_at} if occurred_at else {}
    emit_platform_event(
        session,
        PlatformEvent(
            type=event_type,
            module_id="idm",
            payload={
                "identity_id": item.identity_id,
                "account_id": item.account_id,
                "function_id": item.function_id,
                "organization_unit_id": item.organization_unit_id,
                "applies_to_subunits": item.applies_to_subunits,
                "source": item.source,
                "delegated_from_assignment_id": (
                    item.delegated_from_assignment_id
                ),
                "acting_for_account_id": item.acting_for_account_id,
                "valid_from": (
                    item.valid_from.isoformat()
                    if item.valid_from is not None
                    else None
                ),
                "valid_until": (
                    item.valid_until.isoformat()
                    if item.valid_until is not None
                    else None
                ),
                "is_active": item.is_active,
            },
            actor=EventActorRef(type=actor_type, id=actor_id),
            tenant=EventTenantRef(id=item.tenant_id),
            subject=EventObjectRef(
                type="organization_function",
                id=item.function_id,
            ),
            resource=EventObjectRef(
                type="organization_function_assignment",
                id=item.id,
            ),
            classification="internal",
            **event_options,
        ),
    )


__all__ = ["emit_assignment_event"]