export function mergeCampaignAvailability(existingAvailability, campaignIds) {
  const existingEnabled =
    existingAvailability?.enabled &&
    typeof existingAvailability.enabled === "object" &&
    !Array.isArray(existingAvailability.enabled)
      ? existingAvailability.enabled
      : {};
  const normalizedCampaignIds = [
    ...new Set(campaignIds.filter((id) => typeof id === "string" && id.length > 0)),
  ];
  const campaignIdSet = new Set(normalizedCampaignIds);
  const preservedEntries = Object.entries(existingEnabled).filter(
    ([id]) => !campaignIdSet.has(id),
  );

  return {
    schemaVersion: 1,
    enabled: Object.fromEntries([
      ...preservedEntries,
      ...normalizedCampaignIds.map((id) => [id, true]),
    ]),
  };
}