feat: add removable reference feature vertical slice

src/features/reference-feature/contracts/reference-mapper.ts

@@ -0,0 +1,54 @@
+import {
+  createReferenceResource,
+  type ReferenceResource,
+} from "../domain/reference-resource.js";
+
+export type ReferenceResourceView = Readonly<{
+  resourceId: string;
+  title: string;
+  createdAtLabel: string | null;
+  optimistic?: boolean;
+}>;
+
+function mapReferenceDto(value: unknown): ReferenceResource {
+  if (!value || typeof value !== "object") {
+    throw new TypeError("Validated reference DTO is required");
+  }
+  const dto = value as Record<string, unknown>;
+  if (typeof dto.id !== "string" || typeof dto.name !== "string") {
+    throw new TypeError("Validated reference DTO invariants were breached");
+  }
+  return createReferenceResource({
+    id: dto.id,
+    displayName: dto.name,
+    createdAt: typeof dto.createdAt === "string" ? dto.createdAt : null,
+  });
+}
+
+export function mapReferenceOperation(
+  operationId: string,
+  payload: unknown,
+): ReferenceResource | readonly ReferenceResource[] {
+  if (operationId === "LIST_REFERENCE_RESOURCES") {
+    if (!Array.isArray(payload)) throw new TypeError("Expected a reference list");
+    return payload.map(mapReferenceDto);
+  }
+  if (operationId === "CREATE_REFERENCE_RESOURCE") {
+    return mapReferenceDto(payload);
+  }
+  throw new TypeError(`No reference mapper registered for ${operationId}`);
+}
+
+export function toReferenceView(
+  resource: ReferenceResource,
+  formatDate: (value: Date) => string = (value) =>
+    new Intl.DateTimeFormat("ko-KR").format(value),
+): ReferenceResourceView {
+  return Object.freeze({
+    resourceId: resource.id,
+    title: resource.displayName,
+    createdAtLabel: resource.createdAt
+      ? formatDate(new Date(resource.createdAt))
+      : null,
+  });
+}