/**
 * apps/worker — sharp accessor + a minimal structural type for the surface
 * the files pipeline uses.
 *
 * sharp ships CJS types (`export =`) plus a separate ESM `dist/index` type
 * surface (nodenext resolution) that lags the runtime API (e.g. no
 * `limitInputPixels` on the ESM `Sharp` type). Rather than couple the
 * pipeline to sharp's type churn, we consume a small structural interface —
 * the exact methods we call — and resolve the callable once (ESM
 * `import("sharp")` puts the callable on `.default`).
 */

/** The pipeline's view of a sharp pipeline instance. */
export interface SharpInstance {
  rotate(): SharpInstance;
  resize(opts: { width: number; withoutEnlargement?: boolean }): SharpInstance;
  metadata(): Promise<{ width?: number; height?: number; orientation?: number }>;
  toFormat(name: string): SharpInstance;
  png(): SharpInstance;
  toBuffer(): Promise<Buffer>;
}

/** Sharp constructor options the pipeline uses. `limitInputPixels` is a
 *  CONSTRUCTOR option (input memory cap), NOT a pipeline method. */
export interface SharpOptions {
  limitInputPixels?: number;
}

export type SharpConstructor = (input: string | Buffer, options?: SharpOptions) => SharpInstance;

let cached: SharpConstructor | null = null;

export async function getSharp(): Promise<SharpConstructor> {
  if (cached) return cached;
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  const mod: any = await import("sharp");
  const fn: SharpConstructor = (mod?.default ?? mod) as SharpConstructor;
  cached = fn;
  return fn;
}