export type GameplayFrameRateLimit = 30 | 60 | "display";
export type PreviewFrameRateLimit = 15 | 30 | 60 | "display";

export const GAMEPLAY_FRAME_RATE_LIMITS: readonly GameplayFrameRateLimit[] = [30, 60, "display"];
export const PREVIEW_FRAME_RATE_LIMITS: readonly PreviewFrameRateLimit[] = [15, 30, 60, "display"];

export const DEFAULT_GAMEPLAY_FRAME_RATE_LIMIT: GameplayFrameRateLimit = 60;
export const DEFAULT_PREVIEW_FRAME_RATE_LIMIT: PreviewFrameRateLimit = 30;

export function normalizeGameplayFrameRateLimit(
  value: unknown,
  fallback: GameplayFrameRateLimit = DEFAULT_GAMEPLAY_FRAME_RATE_LIMIT,
): GameplayFrameRateLimit {
  return value === 30 || value === 60 || value === "display" ? value : fallback;
}

export function normalizePreviewFrameRateLimit(
  value: unknown,
  fallback: PreviewFrameRateLimit = DEFAULT_PREVIEW_FRAME_RATE_LIMIT,
): PreviewFrameRateLimit {
  return value === 15 || value === 30 || value === 60 || value === "display" ? value : fallback;
}

export function nextFrameRateLimit<T extends number | "display">(
  current: T,
  order: readonly T[],
): T {
  const index = order.indexOf(current);
  return order[(index + 1) % order.length] ?? order[0] ?? current;
}

export function frameRateLimitLabel(limit: number | "display"): string {
  return limit === "display" ? "Display refresh" : `${limit} FPS`;
}

export function numericFrameRateLimit(limit: number | "display"): number | null {
  return limit === "display" ? null : limit;
}