promotions/docs/wallet_refactor.md

# Wallet Refactor — 2026-08-25

Brings promotions' wallet settings and deposit routing in line with the naming/routing
convention already rolled out to `advertising`, `settlement`, and `ipg`. No behavior in
those sibling repos changed as part of this — this document covers promotions only, with
the sibling commits cited as precedent for why the shape of the fix looks the way it does.

---

## 1. The bug

`Promotion.promote()` (`apps/promotions/models.py`) submits every payout as a wallet
deposit. A deposit call takes two wallet references:

- `payer_wallet` — the call-target / URL param — the **company-side** pool the money is
  drawn from.
- `payee_wallet` — a field in the request body — the **user-side** wallet type the
  recipient is credited into.

Before this change, both were the same setting:

```python
"payee_wallet": settings.WALLET_REWARD,
...
submit_response = deposit_to_user_wallet_submit(settings.WALLET_REWARD, data)
...
verify_response = deposit_to_user_wallet_verify(settings.WALLET_REWARD, submit_response.uuid)
```

So every promotion payout was routed **out of and into the same wallet type** — there was
no real company-owned pool distinct from the user-side wallet category. This is the same
defect fixed in `settlement` (commit `cc2ffb9`, 2026-08-16):

> "Withdraw requests were passing the user's own source wallet (WALLET_RIAL/WALLET_REWARD)
> as the withdrawal's destination wallet param, so every settlement payout and commission
> was routed back into the same wallet type it came from."

and still open, but flagged, in `advertising`'s `wallet_service_integration.md` §6.2 for
`AdPayment.refund_balance()`.

A second, smaller bug rode along: `Recipient.get_wallet_category_uuid()` fell back to
`settings.WALLET_PROMOTION_CATEGORY_UUID` — a setting that was never defined anywhere in
`main/settings.py`. It happened to never be called from the live deposit path (which
hardcoded `WALLET_REWARD` instead), so this was latent, not yet crashing anything — but it
would have raised `AttributeError` the moment anyone wired it in, which is exactly what
this change does.

---

## 2. The fix

### 2.1 Settings renamed to match the shared cross-repo convention

The two user-side wallet-type UUIDs are the same wallet-service UUIDs referenced by
`advertising`, `settlement`, and `ipg` — they're renamed to match those repos' naming
(`advertising`, then propagated to `settlement` in `cc2ffb9` and `ipg` in `7dcb730`):

| Before | After |
|---|---|
| `WALLET_RIAL` | `WALLET_RIAL_DEPOSIT` |
| `WALLET_REWARD` | `WALLET_USER_BILLBOARD_VISIT_INCOME` |
| *(did not exist)* | `WALLET_PROMOTIONS_TRANSIT` — new |

`WALLET_RIAL_DEPOSIT` isn't read by any code path in promotions today (it wasn't before
either, under its old name) — it's renamed for consistency and in case a future feature
here needs to read a user's rial balance via `get_user_wallets()`.

### 2.2 A dedicated company-side wallet for payouts

`WALLET_PROMOTIONS_TRANSIT` is new: the company pool promotion payouts are drawn from,
used only as `payer_wallet` (the deposit call-target). It is never the same UUID as any
user-side wallet type. This is the promotions equivalent of `WALLET_SETTLEMENT_TRANSIT`
(settlement) / `WALLET_ADVERTISING_TRANSIT` (advertising).

**This is a required new environment variable.** It ships in `.env.example` as a
placeholder UUID (`00000000-...`) with a `TODO(you)` comment — same pattern as
settlement's `.env.example`. **It needs a real wallet-type UUID provisioned by the
wallet-service team before this service can submit a deposit in any environment**, and
your local/staging/prod `.env` files need the rename applied (`WALLET_RIAL` →
`WALLET_RIAL_DEPOSIT`, `WALLET_REWARD` → `WALLET_USER_BILLBOARD_VISIT_INCOME`) plus this
new key added, or `main/settings.py` will fail at startup with
`decouple.UndefinedValueError`.

### 2.3 Per-recipient destination routing wired in

`Recipient.get_wallet_category_uuid()` existed already (`self.wallet_uuid or <fallback>`)
but nothing called it — every payout hardcoded `WALLET_REWARD` as `payee_wallet`
regardless of what a `Recipient` might specify. It's now the actual source of
`payee_wallet` in `Promotion.promote()`:

```python
payee_wallet = self.recipient.get_wallet_category_uuid()
```

So a `Recipient` with its own `wallet_uuid` set now routes its payout to that wallet type
instead of the default; a `Recipient` with `wallet_uuid=None` falls back to
`WALLET_USER_BILLBOARD_VISIT_INCOME`. This mirrors `EscrowWalletPayment.destination_wallet`
in `advertising` — a per-row field read at call time instead of one hardcoded constant —
without inventing a new abstraction: `Recipient.wallet_uuid` and
`get_wallet_category_uuid()` already existed in this codebase, they just weren't
connected to anything.

---

## 3. Before / after, side by side

### `main/settings.py`

```diff
 WALLET_BASE_PUBLIC_URL = config('WALLET_BASE_PUBLIC_URL', default=None, cast=str)
-WALLET_RIAL = config('WALLET_RIAL', cast=str)
-WALLET_REWARD = config('WALLET_REWARD', cast=str)
+WALLET_RIAL_DEPOSIT = config('WALLET_RIAL_DEPOSIT', cast=str)
+WALLET_USER_BILLBOARD_VISIT_INCOME = config('WALLET_USER_BILLBOARD_VISIT_INCOME', cast=str)
+# Company-side pool promotion payouts are drawn from; must be distinct from the user-side
+# wallet above. TODO(you): replace with the real wallet-type UUID from the wallet service.
+WALLET_PROMOTIONS_TRANSIT = config('WALLET_PROMOTIONS_TRANSIT', cast=str)
```

### `apps/promotions/models.py` — `Recipient.get_wallet_category_uuid()`

```diff
     def get_wallet_category_uuid(self):
-        return self.wallet_uuid or settings.WALLET_PROMOTION_CATEGORY_UUID
+        return self.wallet_uuid or settings.WALLET_USER_BILLBOARD_VISIT_INCOME
```

### `apps/promotions/models.py` — `Promotion.promote()`

```diff
         payment_uuid = str(self.uuid)

+        payee_wallet = self.recipient.get_wallet_category_uuid()
+
         data = {
             "uuid": payment_uuid,
             "payee": str(self.user_uuid),
             "payee_type": 1,
-            "payee_wallet": settings.WALLET_REWARD,
+            "payee_wallet": payee_wallet,
             "amount": self.promotion_amount,
             "details": {
                 'description': str(_(self.recipient.label)),
                 'reference_id': str(self.pk),
                 'application_details_url': ''
             },
         }

         try:
-            submit_response = deposit_to_user_wallet_submit(settings.WALLET_REWARD, data)
+            submit_response = deposit_to_user_wallet_submit(settings.WALLET_PROMOTIONS_TRANSIT, data)
             ...
         try:
-            verify_response = deposit_to_user_wallet_verify(settings.WALLET_REWARD, submit_response.uuid)
+            verify_response = deposit_to_user_wallet_verify(settings.WALLET_PROMOTIONS_TRANSIT, submit_response.uuid)
```

### What the deposit call looks like now, end to end

| | Before | After |
|---|---|---|
| `payer_wallet` (call-target, company money source) | `WALLET_REWARD` | `WALLET_PROMOTIONS_TRANSIT` |
| `payee_wallet` (body, user-side credit type) | `WALLET_REWARD` (same UUID as source) | `Recipient.wallet_uuid`, falling back to `WALLET_USER_BILLBOARD_VISIT_INCOME` |
| Per-recipient routing | Not possible — one hardcoded constant | Possible — set `Recipient.wallet_uuid` |

---

## 4. Files touched

| File | Change |
|---|---|
| `main/settings.py` | Renamed `WALLET_RIAL`→`WALLET_RIAL_DEPOSIT`, `WALLET_REWARD`→`WALLET_USER_BILLBOARD_VISIT_INCOME`; added `WALLET_PROMOTIONS_TRANSIT`. |
| `apps/promotions/models.py` | `Recipient.get_wallet_category_uuid()` fallback fixed to point at a setting that actually exists; `Promotion.promote()` now uses `WALLET_PROMOTIONS_TRANSIT` as `payer_wallet` and `recipient.get_wallet_category_uuid()` as `payee_wallet`. |
| `.env.example` | New — didn't exist before. Documents every `config()` var read by `main/settings.py`, including the new wallet keys as placeholders. |
| `README.md` | Config reference table updated to the renamed/new settings. |

Not touched: `apps/promotions/tests.py` — its wallet mocks patch the client functions
directly (`patch('apps.promotions.models.deposit_to_user_wallet_submit', ...)`) rather
than asserting on which UUID was passed, so they don't need updating for this change, but
they also don't exercise the routing fix — there's no test asserting `payer_wallet` /
`payee_wallet` on the call. `apps/promotions/handlers.py` (the dead processor/handler
scaffolding noted in the README's watch list) — unrelated, left as-is.

---

## 5. What you need to do before this runs anywhere

1. Get a real wallet-type UUID for `WALLET_PROMOTIONS_TRANSIT` from the wallet-service
   team — it must be a genuine, dedicated pool, not a reused existing UUID (that's the
   exact bug this change fixes).
2. In every environment's `.env` (local, staging, prod — none are checked into this repo):
   - Rename `WALLET_RIAL` → `WALLET_RIAL_DEPOSIT` (same value, key renamed).
   - Rename `WALLET_REWARD` → `WALLET_USER_BILLBOARD_VISIT_INCOME` (same value, key renamed).
   - Add `WALLET_PROMOTIONS_TRANSIT` with the real UUID from step 1.
3. Until step 2 is done in a given environment, `main/settings.py` will fail to import
   with `decouple.UndefinedValueError: WALLET_RIAL_DEPOSIT not found` — the service won't
   start at all, not just fail at payout time. Treat this as a deploy-blocking config
   change, not a code-only one.

---

## 6. Follow-up: explicit per-recipient wallet destination (2026-08-25)

Not every payout is a cash-like user reward. Some fund billboard/ad credit instead — money
that should land in the **advertising** service's own transit wallet, not the user's
personal reward wallet.

An earlier version of this follow-up tried to infer the destination from
`PromotionTypeChoices` (`first_ad_view` / `capture` / `first_ad_create`), a promotion
*category* field that existed but had never been given real values. That was reverted: it
buried a wallet-routing decision inside a general-purpose categorization field, coupling
two things that should vary independently — a promotion's category and where its money
goes are not the same fact, and the next new promotion type would need someone to remember
to also classify it for wallet purposes.

Instead, `Recipient` gets a field that says the routing decision directly:

```python
class WalletDestinationChoices(models.TextChoices):
    USER_REWARD = 'user_reward', _('user reward wallet')
    ADVERTISING_TRANSIT = 'advertising_transit', _('advertising transit wallet')
```

| `wallet_destination` | Nature | Resolves to |
|---|---|---|
| `user_reward` (default) | Cash-like user reward | `WALLET_USER_BILLBOARD_VISIT_INCOME` |
| `advertising_transit` | Billboard/ad credit | `WALLET_ADVERTISING_TRANSIT` (advertising's own company pool) |

`PromotionTypeChoices` is left as it was before any of this — an empty enum, unused. It's
not part of this decision.

### Changes

- `main/settings.py` — new `WALLET_ADVERTISING_TRANSIT` setting. Same wallet-service UUID
  as advertising's own setting of the same name — copy that repo's real value in, don't
  provision a second UUID for the same wallet.
- `apps/promotions/models.py`:
  - New `WalletDestinationChoices` enum, next to the existing `RecipientTypeChoices`.
  - New `Recipient.wallet_destination` field (`CharField`, `db_index=True`, default
    `USER_REWARD`) — a real DB column, unlike the earlier `promotion_type` attempt which
    only changed field-level `choices=` metadata.
  - `Recipient.get_wallet_category_uuid()`:

    ```python
    def get_wallet_category_uuid(self):
        if self.wallet_uuid:
            return self.wallet_uuid

        if self.wallet_destination == WalletDestinationChoices.ADVERTISING_TRANSIT:
            return settings.WALLET_ADVERTISING_TRANSIT

        return settings.WALLET_USER_BILLBOARD_VISIT_INCOME
    ```

    Priority order: an explicit `Recipient.wallet_uuid` always wins (the per-recipient raw
    override from the original refactor above); otherwise `wallet_destination` picks the
    wallet type; `user_reward` is the default so existing rows behave exactly as before
    this change until someone opts them into `advertising_transit`.
- `apps/promotions/migrations/0010_recipient_wallet_destination.py` — new migration adding
  the column, `AddField` with `default='user_reward'` so existing rows backfill safely.
- `apps/promotions/tests.py` — the `first-ad-create` fixture now sets
  `wallet_destination=WalletDestinationChoices.ADVERTISING_TRANSIT`;
  `test_first_ad_create_event_status_processed` asserts the deposit call actually receives
  `WALLET_PROMOTIONS_TRANSIT` as `payer_wallet` and `WALLET_ADVERTISING_TRANSIT` as
  `payee_wallet`; `test_get_wallet_category_uuid_routing` unit-tests all four routing cases
  directly against `Recipient.get_wallet_category_uuid()`.
- `README.md` — config reference table and the playbook's step 3 example updated to show
  setting `wallet_destination` on a new `Recipient`.

### What's still manual

- Existing `Plan`/`Recipient` rows in a live database default to `wallet_destination='user_reward'`
  on migrate — behavior for them doesn't change. Whoever owns the real `capture` /
  `first-ad-create` plans needs to explicitly set `wallet_destination='advertising_transit'`
  on their `Recipient` rows (via admin or a follow-up data migration) for those specific
  payouts to actually route to the advertising transit wallet.
- `WALLET_ADVERTISING_TRANSIT` is a second **required** env var on top of
  `WALLET_PROMOTIONS_TRANSIT` — same deploy-blocking caveat as §5: missing it fails
  `main/settings.py` import, not just a payout at runtime.
- This migration hasn't been run against a real database in this environment (no local
  `.env`/DB configured here) — run `manage.py migrate` and confirm `0010` applies cleanly
  before deploying.