// Walk a directory tree with a recursive async generator and hash every file
// using map() with bounded concurrency. Results stream back in completion order.
// Requires Node v24+.
//
// Run: node examples/bounded-map/main.ts [dir]

import { readdir } from 'node:fs/promises';
import { join } from 'node:path';
import { workers, map, inert } from '../../src/index.ts';
import type { Task } from '../../src/index.ts';
import { hashFile, type FileHash } from './hash-file.ts';

const root = process.argv[2] ?? './src';

{
  using run = workers();
  const start = performance.now();
  let count = 0;
  for await (const { path, hash } of map(run, walk(root), { concurrency: 4 })) {
    console.log(`${hash.slice(0, 12)}  ${path}`);
    count++;
  }
  console.log(`\nhashed ${count} files in ${(performance.now() - start).toFixed(0)}ms`);
}

async function* walk(dir: string): AsyncGenerator<Task<FileHash>> {
  for (const entry of await readdir(dir, { withFileTypes: true })) {
    const p = join(dir, entry.name);
    if (entry.isDirectory()) {
      yield* walk(p);
    } else {
      yield inert(hashFile(p));
    }
  }
}