export type DiscoverNearbyProfileWire = {
  id: string;
  display_name: string | null;
  birth_date: string | null;
  distance_m: number;
  primary_photo_path: string | null;
  photo_url?: string | null;
  is_online: boolean | null;
  last_seen?: string | null;
  is_creator?: boolean | null;
  has_new_media?: boolean | null;
  traveling?: boolean | null;
  right_now_until?: string | null;
  is_right_now?: boolean | null;
};

export type DiscoverGridProfileItemWire = {
  kind: 'profile';
  id: string;
  person: DiscoverNearbyProfileWire;
};

export type DiscoverGridAdItemWire = {
  kind: 'ad';
  id: string;
  placement?: string;
};

export type DiscoverGridItemWire = DiscoverGridProfileItemWire | DiscoverGridAdItemWire;

export function profileAgeFromBirthDate(birthDate: string | null | undefined): number | null {
  if (!birthDate) return null;
  const born = new Date(birthDate);
  if (Number.isNaN(born.getTime())) return null;
  const today = new Date();
  let age = today.getFullYear() - born.getFullYear();
  const monthDelta = today.getMonth() - born.getMonth();
  if (monthDelta < 0 || (monthDelta === 0 && today.getDate() < born.getDate())) {
    age -= 1;
  }
  return age >= 0 ? age : null;
}

export function formatDistanceLabel(
  distanceM: number,
  unit: 'metric' | 'imperial' = 'metric',
): string {
  if (unit === 'imperial') {
    const feet = distanceM * 3.28084;
    if (feet < 528) return `${Math.round(feet)} ft`;
    const miles = distanceM / 1609.34;
    return miles < 10 ? `${miles.toFixed(1)} mi` : `${Math.round(miles)} mi`;
  }

  if (distanceM < 1000) return `${Math.round(distanceM)} m`;
  const km = distanceM / 1000;
  return km < 10 ? `${km.toFixed(1)} km` : `${Math.round(km)} km`;
}

export type PresenceStatus = 'online' | 'recent' | 'offline';

export function getPresenceStatus(lastSeen?: string | null): PresenceStatus {
  if (!lastSeen) return 'offline';
  const seenAt = new Date(lastSeen).getTime();
  if (Number.isNaN(seenAt)) return 'offline';
  const deltaMs = Date.now() - seenAt;
  if (deltaMs <= 5 * 60 * 1000) return 'online';
  if (deltaMs <= 24 * 60 * 60 * 1000) return 'recent';
  return 'offline';
}

export function isDiscoverGridItem(value: unknown): value is DiscoverGridItemWire {
  if (!value || typeof value !== 'object') return false;
  const kind = (value as { kind?: unknown }).kind;
  return kind === 'profile' || kind === 'ad';
}

export function readDiscoverGridItems(data: Record<string, unknown>, ref: string): DiscoverGridItemWire[] {
  const raw = ref.split('.').reduce<unknown>((acc, key) => {
    if (acc && typeof acc === 'object' && key in (acc as Record<string, unknown>)) {
      return (acc as Record<string, unknown>)[key];
    }
    return undefined;
  }, data);

  if (!Array.isArray(raw)) return [];
  return raw.filter(isDiscoverGridItem);
}