# Admin Vouchers API — Changes

Two updates to the admin vouchers list endpoint (`GET /admin/v1/vouchers`).

## 1. Redeemed-by user info

Each voucher in the response now includes a `redeemedBy` object identifying the user who redeemed it, resolved from the auth database:

```json
{
  "voucherId": "...",
  "code": "ABCD-1234",
  "status": "Redeemed",
  "redeemedByUserId": "auth0|123",
  "redeemedBy": {
    "id": "auth0|123",
    "fullName": "Filan Fisteku",
    "email": "filan@example.com"
  },
  "redeemedAt": "2026-07-01T10:15:00Z"
}
```

- `redeemedBy` is `null` for vouchers that haven't been redeemed.
- The existing `redeemedByUserId` field is unchanged, so nothing breaks for current consumers.
- Users are batch-loaded per page (one query for all distinct user IDs), following the same pattern as the admin pay-to-view purchases endpoint.

### Files changed

| File | Change |
|---|---|
| `core/PicTv.Application/Dtos/Vouchers/VoucherDto.cs` | Added `RedeemedBy` property and new `VoucherRedeemedByDto` (`Id`, `FullName`, `Email`) |
| `core/PicTv.Application/Vouchers/Queries/GetAdminVouchers/GetAdminVouchersQueryHandler.cs` | Injected `IAuthDbContext`; added `PopulateRedeemedByAsync` to enrich results with user name and email |

## 2. Order by reason

New optional query parameter `orderByReason` (boolean, default `false`):

```
GET /admin/v1/vouchers?page=1&orderByReason=true
```

- When `true`, vouchers are sorted alphabetically by `reason`, with newest-first (`createdAt` descending) as the tiebreaker.
- When omitted or `false`, the existing default ordering (newest first by `createdAt`) applies.

### Files changed

| File | Change |
|---|---|
| `api/PicTv.Api/Routes/VoucherRoutes.cs` | Added `orderByReason` query parameter to the admin list endpoint |
| `core/PicTv.Application/Vouchers/Queries/GetAdminVouchers/GetAdminVouchersQuery.cs` | Added `OrderByReason` property (defaults to `false`) |
| `core/PicTv.Application/Vouchers/Queries/GetAdminVouchers/GetAdminVouchersQueryHandler.cs` | Applies `OrderBy(Reason).ThenByDescending(CreatedAt)` when the flag is set |

## Notes

- No database or migration changes — `RedeemedByUserId`, `RedeemedAt`, and `Reason` were already stored on the `Voucher` entity.
- If more sort columns are needed later (status, redeemed date, …), the boolean flag should be replaced with an `orderBy` enum parameter.