export interface TuiRenderOptions {
  exitOnCtrlC?: boolean;
  targetFps?: number;
  enableMouseMovement?: boolean;
  useMouse?: boolean;
  /**
   * Terminal buffer mode for OpenTUI-backed renderers.
   * - 'alternate': full-screen alternate buffer
   * - 'standard': render in the main buffer
   */
  bufferMode?: "alternate" | "standard";
  [key: string]: unknown;
}

export function getUseAlternateScreen(options: TuiRenderOptions | undefined): boolean {
  const mode = options?.bufferMode;
  if (mode === "alternate") return true;
  if (mode === "standard") return false;

  // Runtime defaults to standard-buffer rendering unless alternate is explicitly requested.
  return false;
}

export type OpenTuiRendererOptions = {
  exitOnCtrlC: boolean;
  targetFps: number;
  enableMouseMovement: boolean;
  useMouse: boolean;
  useAlternateScreen: boolean;
} & TuiRenderOptions;

export function resolveOpenTuiRendererOptions(
  options: TuiRenderOptions | undefined,
): OpenTuiRendererOptions {
  const value = options ?? {};
  const useMouse = typeof value.useMouse === "boolean" ? value.useMouse : false;

  return {
    ...value,
    exitOnCtrlC: value.exitOnCtrlC ?? true,
    targetFps: value.targetFps ?? 30,
    enableMouseMovement: value.enableMouseMovement ?? true,
    useMouse,
    useAlternateScreen: getUseAlternateScreen(value),
  };
}