# Story 1.8: Legacy Identifier Linking for Extension Records

Status: ready-for-dev

## Story

As a a system user,
I want extension records to store and validate legacy identifier references on creation,
so that all new capabilities join deterministically to legacy Access records in workflows and reports.

## Acceptance Criteria

1. **Given** a new extension record is created (municipality profile, election job, service config) **When** it is saved **Then** it stores the appropriate legacy identifier (ID, JCode/JurisCode, or KitID) as a required foreign reference
2. **Given** an extension record references a legacy identifier **When** the anti-corruption layer executes a join **Then** it returns the correct legacy record with no ambiguity across all active records
3. **Given** an extension record is submitted with an invalid or non-existent legacy identifier **When** validation runs before save **Then** the save is rejected with a descriptive validation error identifying the invalid reference
4. **Given** the nightly integrity check runs **When** it evaluates all extension-to-legacy joins **Then** it reports referential consistency and flags any records that fail to resolve, targeting 99.9% consistency (NFR13)

## Tasks / Subtasks

- [ ] Implement story behavior in aligned backend/frontend modules (AC: #1)
  - [ ] Add or update API/service/UI components required by the story scope
  - [ ] Keep legacy Access entities read-only and route writes to extension-layer structures
- [ ] Cover acceptance criteria #2 in implementation and tests (AC: #2)
  - [ ] Add validation/error handling and UX state updates as needed
- [ ] Cover acceptance criteria #3 in implementation and tests (AC: #3)
  - [ ] Add validation/error handling and UX state updates as needed
- [ ] Cover acceptance criteria #4 in implementation and tests (AC: #4)
  - [ ] Add validation/error handling and UX state updates as needed
- [ ] Validate and document completion evidence
  - [ ] Verify build/tests for touched modules
  - [ ] Capture changed files and any migration/config implications

## Dev Notes

- Follow Epic 1 architecture constraints: ASP.NET Core + React separation, RBAC-aware patterns, and immutable legacy tables.
- Reuse shared component and workflow patterns defined in UX and architecture docs; avoid parallel custom implementations.
- Keep changes scoped to this story; do not pull forward Epic 2+ features.

### Project Structure Notes

- Backend: `BriansClientRouteReports.Server/`
- Frontend: `brians-client-route-reports-client/`
- Story artifacts: `_bmad-output/implementation-artifacts/`

### References

- Story source: `_bmad-output/planning-artifacts/epics.md` (Epic 1 / Story 1.8)
- Architecture constraints: `_bmad-output/planning-artifacts/architecture.md`
- UX patterns: `_bmad-output/planning-artifacts/ux-design-specification.md`

## Dev Agent Record

### Agent Model Used

GPT-5 Codex

### Debug Log References

- Story generated from epic source and architecture/UX planning artifacts.

### Completion Notes List

- Story context created and marked ready-for-dev.

### File List

- `_bmad-output/implementation-artifacts/1-8-legacy-identifier-linking-for-extension-records.md`