# Report Sharing Permissions

## Objective

Share a report with specific people without opening the data behind it.

Per-report access control inside the app, distinguishing what each recipient may do with the report.

## 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. Give each saved report its own access list, separate from the workspace-wide role. Reports combine data that not everyone should see together.
2. Model four distinct grants: view, edit, duplicate, and reshare. Being able to read a report is not permission to hand it to someone else.
3. Enforce the underlying data permissions on every render. A share grants access to the report definition, never a bypass of row-level security on the source.
4. Show the current access list on the report, so an owner can see who can open it without digging through settings.
5. Do NOT build account-less public links here — tokenized external sharing is owned by Signed Share Links. Role definitions are owned by User Roles; read from them rather than defining new roles.

## 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

- A recipient without access to a source must see that widget explained, not a blank panel or a raw permission error.
- Removing someone from the workspace must revoke their report shares immediately, not leave an orphaned grant.
- A duplicated report must not inherit the original's access list by default — the copy starts with the duplicator.
- Downgrading a user's workspace role must narrow their report access too; the more restrictive of the two wins.
- An owner leaving must not strand a report with no one able to manage it. Reassign ownership or block the departure.
- Aggregate figures can leak restricted rows. If a recipient cannot see the underlying rows, do not show them the total derived from those rows.

## 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

- [ ] Each saved report has its own access list independent of workspace roles.
- [ ] View, edit, duplicate, and reshare are separately grantable.
- [ ] Row-level security on source data is enforced for every viewer, sharer or not.
- [ ] Losing workspace membership revokes report access with no delay.
- [ ] Widgets a recipient cannot see are explained rather than silently blank or broken.
- [ ] A duplicated report does not carry the original's shares.
- [ ] 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.