import { describe, it, expect } from 'vitest'
import { AssetManager } from '@/lib/assets/assetManager'
import { buildAssetsMetadata, type AssetMetaItem } from '@/lib/exporter/assets.meta'
import crypto from 'node:crypto'

function u8pattern(n: number): Uint8Array {
  const arr = new Uint8Array(n)
  for (let i = 0; i < n; i++) arr[i] = (i * 131 + 7) & 0xff
  return arr
}

function sha256B64(bytes: Uint8Array): string {
  const h = crypto.createHash('sha256')
  h.update(Buffer.from(bytes))
  return h.digest('base64')
}

describe('assets.json integrity = real SHA-256(base64)', () => {
  it('integrity equals sha256-<base64(sha256(bytes))>', async () => {
    const am = new AssetManager({ maxBytes: 1024 * 1024, allowedExts: ['png'] })
    const bytes = u8pattern(64)
    await am.add({ name: 'hero.png', type: 'image/png', bytes })
    const out = buildAssetsMetadata(am)
    const json = new TextDecoder().decode(out)
    const obj = JSON.parse(json) as { assets: AssetMetaItem[] }
    expect(obj.assets.length).toBe(1)
    const a = obj.assets[0]
    const expected = 'sha256-' + sha256B64(bytes)
    expect(a.integrity).toBe(expected)
  })
})