# Approval Requests

## Objective

Ask a specific person to approve or reject something, and record what they decided.

A reusable request-and-decide flow attached to any record, with an auditable decision history.

## Before You Begin

This feature is being added to an application that already exists and already
works. Do not scaffold a new project, and do not assume a blank slate.

Inspect the codebase first and establish:

- The existing application structure and where code of this kind already lives.
- The framework and version in use.
- The existing design system — colours, spacing, typography, and component conventions.
- Existing UI components you can reuse instead of writing new ones.
- The existing database structure, if this feature needs to persist anything.
- The existing authentication and authorization system, if this feature is user-scoped.
- Dependencies already installed, so you don't add a library that duplicates one.
- The existing test setup and conventions.

Only start writing code once you understand the above. If the application
already implements part of this feature, extend it rather than replacing it.

## Implementation Instructions

1. Model a request as its own record linked to the item under review, with a requester, one or more reviewers, a state, and a decision history.
2. Define and enforce who may request, approve, reject, cancel, and reassign. Approving your own request should be blocked unless an admin has deliberately allowed it.
3. Write decisions as append-only entries with an author, a timestamp, and an optional comment. Never edit or delete a recorded decision.
4. Decide up front whether editing the underlying item invalidates an in-flight approval, then enforce it — silently approving content that has since changed is the failure this feature exists to prevent.
5. Do NOT build a general workflow engine with configurable stages and branching. One request, one decision, reassignable. Anything more is a different product.

## UI and UX Requirements

Match the application's existing design system exactly. Reuse its components,
spacing, and typography. This feature should look like it was always there.

## Responsive Requirements

Works on mobile, tablet, and desktop. Touch targets are large enough to hit on a
phone, and nothing overflows horizontally at 320px.

## Accessibility Requirements

- Fully keyboard navigable.
- Correct semantic elements and ARIA roles.
- Visible focus states.
- Meets WCAG AA contrast.
- Dynamic changes are announced to screen readers.
- Respects prefers-reduced-motion.

## Edge Cases

- Two reviewers deciding at the same moment must not produce two contradictory outcomes — the first decision wins and the second is told so.
- A reviewer who loses access to the item must be removed from the request rather than left holding a decision they cannot make.
- Cancelling a request must be distinguishable from rejecting it in the history.
- Requests with no activity need an expiry or a nudge; a queue full of forever-pending items is worse than no queue.
- If the item is deleted or archived, resolve open requests instead of leaving orphans pointing at nothing.
- Reassignment must keep the original requester and the prior comments visible, not reset the trail.

## Testing

Exercise the feature end to end in the running application. Cover every edge case
above, then run the existing test suite and confirm nothing regressed.

## Acceptance Criteria

- [ ] A request can be raised on an item and routed to a named reviewer.
- [ ] Approve, reject, cancel, and reassign are permission-checked server-side.
- [ ] Decisions are immutable and carry author, timestamp, and comment.
- [ ] Concurrent decisions cannot both land.
- [ ] Changing the item applies the documented invalidation rule.
- [ ] Stale requests expire or escalate on a defined schedule.
- [ ] The feature matches the existing design system.
- [ ] No existing functionality is broken.

## Adaptation Rules

- Match the existing design system. Do not introduce a new colour palette,
  spacing scale, or component library.
- Reuse existing components and utilities wherever they fit.
- Follow the naming, file layout, and code style already present.
- Do not upgrade, replace, or remove existing dependencies to make this
  feature fit. Adapt the feature to the app, not the app to the feature.
- Do not break existing functionality. If a change is genuinely required in
  existing code, make the smallest one that works and say so.
- If something in these instructions conflicts with how the application is
  built, follow the application and explain the deviation.

## Final Verification

Before you report the work as done:

1. Re-read the acceptance criteria above and check each one against what you
   actually built.
2. Run the application and exercise the feature end to end.
3. Run the existing test suite and confirm you have broken nothing.
4. Check the feature on mobile, tablet, and desktop widths.
5. Check keyboard navigation and focus handling.
6. Summarize what changed: files added, files modified, and anything you
   deliberately did differently because of how this application is built.

If any acceptance criterion is unmet, fix it before reporting completion.