# OpenSpec Change: enterprise-api-plugin-vatdash-bridge

- **Change ID**: enterprise-api-plugin-vatdash-bridge
- **Package**: `@suaveplan/api-plugin-vatdash-bridge`
- **Category**: api/logistics
- **Target path**: `api/logistics/api-plugin-vatdash-bridge`
- **Status**: PROPOSED
- **Date**: 2026-04-24
- **Reference spec**: `/mnt/s/web/suaveplan/enterprise/api-plugin-vatdash-bridge.md`

---

## Summary

Deliver `@suaveplan/api-plugin-vatdash-bridge` on the genesis branch from scratch at enterprise quality. VATDash integration bridge: VAT return preparation (UK MTD, EU OSS, EU MOSS), transaction tagging (VAT-applicable/exempt/reversed-charge), VAT rate lookups (EC VIES API + configurable override table), digital VAT report generation in JSON/CSV format, and HMRC Making Tax Digital (MTD) submission via pluggable `MtdAdapter`. Routes under `/vatdash`. Per-table SurrealQL. Events: `vatdash:vat-return:submitted`, `vatdash:transaction:tagged`.

---

## Available workspace deps on genesis

| Package | Role |
|---|---|
| `@suaveplan/api` (`workspace:^`) | `definePlugin` |
| `@suaveplan/api-shared` (`workspace:^`) | Helpers |
| `@suaveplan/api-plugin-auth` (`workspace:^`) | `requireAuth`, `requireRole` |
| `@suaveplan/api-plugin-database` (`workspace:^`) | SurrealDB |
| `@suaveplan/api-plugin-export` (`workspace:^`) | Report export |
| `@suaveplan/datetime` (`workspace:^`) | VAT period date arithmetic |
| `@suaveplan/events` (`workspace:^`) | Event bus |
| `@suaveplan/error` (`workspace:^`) | `VatDashError` hierarchy |
| `@suaveplan/audit-logging` (`workspace:^`) | Submission audit |
| `hono` + `@hono/zod-openapi` + `zod` | Routes |
| `@opentelemetry/api` | OTel |

---

## Public API surface

```ts
function createVatdashBridgePlugin(config?: VatdashBridgeConfig): PluginDescriptor
interface MtdAdapter { submitReturn(return: VatReturn): Promise<MtdSubmissionResult> }
// Routes: /vatdash/transactions, /vatdash/vat-rates, /vatdash/returns,
//         /vatdash/returns/:period/submit, /vatdash/returns/:period/report
```

### Error codes

```ts
type VatDashErrorCode =
  | "VATDASH_RETURN_NOT_FOUND"
  | "VATDASH_PERIOD_ALREADY_SUBMITTED"
  | "VATDASH_SUBMISSION_FAILED"
  | "VATDASH_RATE_NOT_FOUND"
  | "VATDASH_TRANSACTION_NOT_FOUND"
```

---

## File layout

```text
api/logistics/api-plugin-vatdash-bridge/
  package.json  tsconfig.json  vitest.config.ts
  surql/ (vat_transaction, vat_rate, vat_return tables)
  src/
    index.ts  events.ts  types/  errors/
    adapters/mtd.port.ts
    services/transaction/  services/vat-rate/  services/vat-return/  services/report/
    routes/vatdash/
  tests/integration.test.ts
```

---

## Impact

Prerequisites: `@suaveplan/api`, `@suaveplan/api-plugin-auth`, `@suaveplan/api-plugin-database`, `@suaveplan/api-plugin-export`, `@suaveplan/datetime`, `@suaveplan/audit-logging`.