# OpenSpec Change: enterprise-browser-packer-browser

- **Change ID**: enterprise-browser-packer-browser
- **Package**: `@suaveplan/packer-browser`
- **Category**: browser
- **Target path**: `browser/storage/packer-browser`
- **Status**: IN PROGRESS
- **Date**: 2026-04-24
- **Reference spec**: `/mnt/s/web/suaveplan/enterprise/packer-browser.md`

---

## Summary

Deliver `@suaveplan/packer-browser` on the genesis branch at enterprise quality. The package provides the browser-side runtime for `@suaveplan/packer` packed media archives: a Service Worker interceptor, a `PackedResourceManager` with fetch + LRU cache, signed-manifest verification via `@suaveplan/crypto`, and SW lifecycle utilities. React hooks (`usePackedResource` etc.) move to a separate `@suaveplan/react-packer` companion. No `react` runtime dep in this package.

---

## Current-state audit (genesis)

Fresh build — does not exist on genesis yet.

---

## Available workspace deps on genesis

| Package | Role |
|---|---|
| `@suaveplan/packer` (`workspace:^`) | Pack/unpack, archive format, manifest |
| `@suaveplan/crypto` (`workspace:^`) | Signed-manifest verification |
| `@suaveplan/events` (`workspace:^`) | Resource lifecycle events |
| `@suaveplan/error` (`workspace:^`) | Typed errors |
| `@suaveplan/types` (`workspace:^`) | `LoggerLike` |
| `@suaveplan/logger` (`workspace:^`) | Structured logging in SW + manager |
| `@suaveplan/schema-registry` (`workspace:^`) | Manifest schema registration |
| `zod` (`catalog:forms`) | Manifest Zod schema |
| `@opentelemetry/api` (`catalog:observability`) | Fetch/cache/decode metrics |
| `tslib` (`catalog:build`) | Runtime helpers |

No `react` in runtime deps.

Dev: `vitest`, `@vitest/coverage-istanbul`, `@playwright/test`, `@suaveplan/testing`.

---

## Preserved public API surface

```ts
// Manager (no React dep)
class PackedResourceManager {
  fetch(assetPath: string): Promise<Blob>
  release(assetPath: string): void
  getMetrics(): PackedResourceManagerMetrics
  clear(): void
}
function createPackedResourceManager(options: ManagerOptions): PackedResourceManager

// Singleton (backward compat at ./singleton subpath)
// import { packedResourceManager } from '@suaveplan/packer-browser/singleton'

// SW utilities
function registerPackedResourceServiceWorker(options?: SwOptions): Promise<ServiceWorkerRegistration>
function unregisterPackedResourceServiceWorker(): Promise<boolean>
function clearServiceWorkerCache(): Promise<void>
function getServiceWorkerCacheStatus(): Promise<SwCacheStatus>

// Types
interface PackedResource { path: string; mimeType: string; size: number; blob: Blob }
type PackedResourceType = 'image' | 'audio' | 'font' | 'video' | 'other'
```

Subpath exports: `./manager`, `./service-worker`, `./utils`, `./singleton`.

---

## New additions for genesis

### 1. React hooks removed → `@suaveplan/react-packer`

`usePackedResource`, `usePackedImage`, `usePackedFont`, `usePackedVideo`, `usePackedAudio` all move to a companion package. This package has zero React runtime dep.

### 2. Signed-manifest verification

`PackedResourceManager` accepts `manifestSignature` in `ManagerOptions`. Before trusting packed resources, verifies signature with `@suaveplan/crypto` ed25519; throws `PACKED_ARCHIVE_SIGNATURE_INVALID` on failure.

### 3. Split `PackedResourceManager`

Into `manager.ts` (orchestration, LRU accounting), `cache.ts` (blob cache, hit/miss, eviction), `loader.ts` (fetch + decode + verify) — each ≤300 lines.

### 4. Service worker unit test

`service-worker/service-worker.ts` unit-tested via a `ServiceWorkerGlobalScope` shim; no coverage gap.

### 5. `createPackedResourceManager` factory

Replaces module-singleton; explicit factory. Singleton available at `./singleton` backward-compat subpath.

### 6. Error codes

`PACKED_RESOURCE_NOT_FOUND`, `SW_REGISTRATION_FAILED`, `PACKED_ARCHIVE_SIGNATURE_INVALID`.

### 7. OTel metrics

Counter `packer.resource_fetch_total`, counter `packer.cache_hits_total`, counter `packer.cache_miss_total`, histogram `packer.decode_ms`.

---

## File layout

```text
browser/storage/packer-browser/
  package.json
  tsconfig.json
  vitest.config.ts
  src/
    index.ts
    error-codes.ts
    manager/
      manager/      (manager.ts — LRU orchestrator, manager.test.ts, manager.md)
      cache/        (cache.ts — blob cache, cache.test.ts, cache.md)
      loader/       (loader.ts — fetch + decode + manifest verify, loader.test.ts, loader.md)
    service-worker/
      service-worker/
        service-worker.ts
        service-worker.md
        service-worker.test.ts   (real SW scope shim)
        index.ts
    utils/
      register-service-worker/
        register-service-worker.ts
        register-service-worker.md
        register-service-worker.test.ts
        index.ts
    singleton/
      index.ts                   (re-exports packedResourceManager singleton)
    types/
      types/
        types.ts
        types.md
        index.ts
  tests/
    integration.test.ts
  e2e/
    packer-browser.spec.ts        (Chromium/Firefox/WebKit SW interception)
```

---

## Impact

**Downstream**: any browser app consuming packed media archives; `@suaveplan/react-packer` (new companion).

**Breaking changes**: `usePackedResource` hooks removed from this package (relocated to companion).

**Prerequisites**: `@suaveplan/packer`, `@suaveplan/crypto`, `@suaveplan/events`, `@suaveplan/error`, `@suaveplan/logger` on Verdaccio.