# Check List Proof of Concept

This repository contains a proof-of-concept implementation for the Check List hybrid reporting solution described in the project documentation.

## What is included

- Node.js REST API (v1) for template, configuration, report, and audit delivery
- static frontend PoC served by Express, split into focused ES modules
- MariaDB schema for configuration data, submitted reports, and audit trail
- seed data with one sample inspection checklist template
- lookup values, image policy, and export profile
- Docker Compose and VS Code Dev Container setup for local development
- service worker with bounded LRU cache for offline support

## Scope of this PoC

Included:
- all endpoints under versioned `/api/v1/` prefix
- batch template endpoint with `?include=definitions` for single-request sync
- template version listing and publishing management
- lookup endpoints with parameter validation
- image rule endpoint with server-side LRU cache and audit trail
- export profile and generic application config endpoints
- report submission endpoint (POST) with UPSERT
- audit log recording for admin mutations
- offline-capable frontend shell split into ES modules
- IndexedDB-based local drafts with multi-store transactions
- dynamic form rendering from template JSON
- local attachment storage with Web Worker image optimization
- report search and status filter
- CSV export for report data
- i18n locale extraction for UI strings
- PWA manifest with SVG icon
- debounced renders and dirty-flag autosave

Not included:
- authentication and authorization
- file attachment upload to server (binary upload requires multer)
- XLSX or ZIP generation (CSV is provided; advanced formats require library vendoring)
- production-grade frontend bundling
- automated test suite

The PoC keeps template content inside a JSON column to reduce initial complexity and speed up delivery. This is deliberate for phase 1 proof-of-concept work.

## Project structure

```text
.
├── .devcontainer/
├── docker-compose.yml
├── package.json
├── public/
│   ├── admin.html              ← administrator workspace
│   ├── app.js                  ← thin orchestrator entry point
│   ├── icon.svg                ← PWA icon
│   ├── index.html              ← legacy combined shell (unused)
│   ├── manifest.webmanifest
│   ├── portal.html
│   ├── styles.css
│   ├── sw.js
│   ├── user.html               ← operator workspace
│   └── js/
│       ├── api.js              ← API communication (versioned base path)
│       ├── constants.js        ← shared constants (DB, API, limits)
│       ├── db.js               ← IndexedDB operations, multi-store tx
│       ├── export.js           ← CSV export and attachment download
│       ├── forms.js            ← dynamic form field creation
│       ├── i18n.js             ← English locale, t() translation
│       ├── image-worker.js     ← OffscreenCanvas Web Worker
│       ├── images.js           ← image optimization with worker fallback
│       ├── renderer.js         ← all render functions with search/filter
│       ├── state.js            ← centralized state management
│       ├── utils.js            ← utility functions
│       └── validation.js       ← shared validation (client-side)
├── scripts/
│   └── test-environment.js
├── sql/
│   ├── schema.sql
│   └── seed.sql
└── src/
    ├── app.js
    ├── server.js
    ├── config/
    │   └── env.js
    ├── db/
    │   └── pool.js
    ├── middleware/
    │   ├── errorHandler.js
    │   └── validateParams.js   ← URL parameter validation
    ├── routes/
    │   ├── configRoutes.js
    │   ├── healthRoutes.js
    │   ├── lookupRoutes.js
    │   ├── reportRoutes.js     ← report submission endpoints
    │   └── templateRoutes.js
    ├── services/
    │   ├── auditService.js     ← audit trail logging
    │   ├── cacheService.js     ← in-memory LRU cache with TTL
    │   ├── configService.js
    │   ├── lookupService.js
    │   ├── reportService.js    ← report CRUD operations
    │   └── templateService.js
    └── utils/
        ├── asyncHandler.js
        └── json.js
```

## File guide

For a junior-friendly explanation of what each main file does, see [PROJECT_FILES_GUIDE.md](PROJECT_FILES_GUIDE.md).

## Run with Docker and Dev Containers

1. Copy `.env.example` to `.env` if you want custom local credentials.
2. In VS Code, run `Dev Containers: Reopen in Container`.
3. Or start the stack directly with `docker compose up -d --build`.

Services:
- API: `http://localhost:3000`
- phpMyAdmin: `http://localhost:8080`
- MariaDB: `localhost:3306`

The workspace is bind-mounted into the `app` container, so project files remain editable from VS Code.

## Database bootstrap

On a fresh MariaDB volume, Docker loads `sql/schema.sql` and `sql/seed.sql` automatically.

If you already have an older local database volume, either recreate it with `docker compose down -v` or import the SQL files manually:

```bash
docker compose exec -T db sh -lc 'mariadb -uroot -p"$MARIADB_ROOT_PASSWORD" < /docker-entrypoint-initdb.d/schema.sql && mariadb -uroot -p"$MARIADB_ROOT_PASSWORD" < /docker-entrypoint-initdb.d/seed.sql'
```

## Validate the environment

Run the smoke test after the containers are up:

```bash
npm run test:environment
```

The test verifies:
- the API health endpoint at `/api/v1/health`
- seeded template data via `/api/v1/templates`
- direct MariaDB connectivity
- phpMyAdmin availability

## Frontend PoC

Open `http://localhost:3000` after the stack is running.

Entry points:
- `http://localhost:3000/` opens the chooser portal
- `http://localhost:3000/user` opens the user workspace directly
- `http://localhost:3000/admin` opens the administrator workspace directly

The frontend demonstrates:
- template sync from the API via batch endpoint
- offline cache via IndexedDB and service worker (LRU-bounded)
- local report creation, switching, search, and filtering
- dynamic form rendering based on the seeded template
- local attachment storage and preview with lazy-loading
- Web Worker image optimization (OffscreenCanvas) with main-thread fallback
- debounced re-renders and dirty-flag autosave
- report submission to backend
- CSV export for report data and individual attachment downloads
- administrator mode for editing image requirements with audit trail
- i18n-ready UI strings extracted to locale file

This frontend is intentionally lightweight and framework-free so the proof of concept stays easy to inspect and adapt. The monolithic app.js has been split into focused ES modules under `public/js/`, and the UI is served as two separate HTML shells (`user.html` for operators, `admin.html` for administrators) sharing a single `app.js` orchestrator with null-guarded element access.

## Administrator mode

Open `http://localhost:3000/admin` or use the chooser page at `http://localhost:3000/`.

The current PoC administrator flow supports:
- policy name changes
- allowed MIME types
- maximum file size
- maximum width and height
- JPEG quality
- oversize behavior
- maximum attachments per field

The frontend saves these values to the backend through `PUT /api/v1/config/image-rules` and refreshes the local cache after save. All admin mutations are recorded in the audit log.

## API endpoints

All endpoints are under the `/api/v1/` prefix.

### Service health

`GET /api/v1/health`

### Templates

- `GET /api/v1/templates` — list active templates
- `GET /api/v1/templates?include=definitions` — batch: all templates with definitions in one request
- `GET /api/v1/templates/:code` — single active template with definition
- `GET /api/v1/templates/:code/versions` — list all versions of a template
- `PUT /api/v1/templates/:code/versions/:versionNumber/publish` — publish a specific template version

### Lookups

- `GET /api/v1/lookups` — list all lookup sets
- `GET /api/v1/lookups/:code` — single lookup set with values

### Configuration

- `GET /api/v1/config/image-rules` — active image policy
- `PUT /api/v1/config/image-rules` — update image policy (audit-logged)
- `GET /api/v1/config/export` — export profile
- `GET /api/v1/config/app-config` — generic app configuration

### Reports

- `GET /api/v1/reports` — list submitted reports (supports `?status=`, `?templateCode=`, `?limit=`, `?offset=`)
- `GET /api/v1/reports/:reportId` — single submitted report
- `POST /api/v1/reports` — submit or update a report (UPSERT by UUID)

## Example response

`GET /api/v1/templates/incoming-inspection`

```json
{
  "code": "incoming-inspection",
  "name": "Incoming Inspection Checklist",
  "description": "PoC template for supplier or incoming goods quality inspection.",
  "version": 1,
  "status": "active",
  "publishedAt": "2026-04-09T10:00:00.000Z",
  "definition": {
    "templateId": "incoming-inspection",
    "templateName": "Incoming Inspection Checklist",
    "version": 1,
    "sections": []
  }
}
```