/**
 * Canonical file schemas and types for SDK API inputs.
 *
 * These helpers model the file objects that Superblocks injects for FilePicker
 * inputs. Use the minimal file-ref contract when you want to pass files by
 * reference to storage integrations, and the readable file contract when your
 * API needs to call `readContentsAsync()` or `readContents()`.
 */

import { z } from "zod";

const readableAsyncMethodSchema = z.custom<
  (mode?: string) => Promise<string | Buffer>
>((value) => typeof value === "function", {
  message: "Expected readContentsAsync to be a function",
});

const readableSyncMethodSchema = z.custom<(mode?: string) => string | Buffer>(
  (value) => typeof value === "function",
  {
    message: "Expected readContents to be a function",
  },
);

/**
 * Minimal file reference contract.
 *
 * Good for by-reference uploads where the storage plugin resolves the file
 * bytes using `$superblocksId`, such as S3 or GCS `uploadMultipleObjects()`.
 */
export const fileRefSchema = z.object({
  name: z.string(),
  type: z.string().optional(),
  $superblocksId: z.string(),
});

/**
 * Runtime-readable file contract.
 *
 * Good for APIs that need to inspect file contents in code via
 * `readContentsAsync()` or `readContents()`.
 */
export const readableFileSchema = fileRefSchema
  .extend({
    size: z.number().optional(),
    extension: z.string().optional(),
    previewUrl: z.string().optional(),
    readContentsAsync: readableAsyncMethodSchema,
    readContents: readableSyncMethodSchema,
  })
  .passthrough();

export type FileRef = z.infer<typeof fileRefSchema>;
export type ReadableFile = z.infer<typeof readableFileSchema>;