import type { Activity } from "@/types";

/**
 * The minimum an activity event must carry to be routable. Centralizing
 * this here means callers can pass an `Activity` (full feed row) or a
 * narrower shape (e.g. a future "activity event" peek payload) — both
 * satisfy the kind + entity-id fields the helper inspects.
 *
 * - `claimId` / `remittanceId` come from the backend `ActivityEvent`
 *   ORM columns (SP21 Task 2.5). `claimId` is set on `claim_*` events;
 *   `remittanceId` is set on `remit_received`.
 * - `npi` is the existing `Activity.npi` field. For `provider_added`
 *   events the provider NPI IS the entity id (the URL target).
 */
export type RoutableEvent = Pick<
  Activity,
  "kind" | "claimId" | "remittanceId" | "npi"
>;

/**
 * Maps an activity event to the URL the operator should land on when
 * clicking the event. Used by:
 *
 * - Dashboard "Recent activity" card (this PR, Task 2.5).
 * - `/activity` log page (Task 2.5 wired here; full integration is
 *   a later task).
 *
 * Returns `null` for kinds that don't have a drill target yet, or
 * when the entity id field is missing on the event. Callers are
 * expected to surface a "coming soon" toast in that case so the click
 * still gives feedback.
 */
export function eventKindToUrl(event: RoutableEvent): string | null {
  switch (event.kind) {
    case "claim_submitted":
    case "claim_paid":
    case "claim_denied":
    case "claim_accepted": {
      if (!event.claimId) return null;
      return `/claims?claim=${encodeURIComponent(event.claimId)}`;
    }
    case "remit_received":
      // Phase 4 — the `RemitDrawer` isn't built yet; the helper stays
      // honest and returns null so the caller's "coming soon" toast
      // fires. When the drawer lands, the route becomes
      // `/remittances?remit=${encodeURIComponent(event.remittanceId ?? "")}`.
      return null;
    case "provider_added": {
      if (!event.npi) return null;
      return `/providers?provider=${encodeURIComponent(event.npi)}`;
    }
    default:
      return null;
  }
}