Add-on purchases (DLC, Season Pass, Battle Pass) previously linked to a
parent *purchase* via the `related_purchase` self-FK. When the base game
was bought inside a multi-game purchase (e.g. a bundle), there was no
per-game purchase to point at — only the whole bundle.
Replace it with a `related_game` FK (Game -> Game): an add-on belongs to
a *game*, which is unambiguous regardless of how the base game was bought.
- models: drop `related_purchase`; add `related_game`
(SET_NULL, related_name="addon_purchases"); require it for non-GAME
types in `save()`.
- forms: replace the parent-purchase picker with a flat `related_game`
game search (reusing SearchSelectWidget/_game_options); drop the now
unused related_purchase_queryset/RelatedPurchaseChoiceField.
- views/urls: remove the obsolete related_purchase_by_game endpoint.
- add_purchase.js: drop the parent-dropdown refetch; keep platform
auto-fill; retarget the type toggle to #id_related_game.
- migration 0020: add -> backfill (related_game = parent's first game by
sort_name) -> remove related_purchase.
- tests: model validation unit tests + an e2e test for the flat picker.
related_game is deliberately game->game so it can later be synced from
IGDB's parent_game without schema changes.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Replace fragile price change detection in Purchase.save() with a
lazy dirty flag approach. A pre_save/post_save signal pair detects
price/currency changes without extra DB queries, and convert_prices()
uses the flag to determine which purchases need conversion.
- Add needs_price_update BooleanField with db_index
- Add pre_save signal to store old price/currency values
- Add post_save signal to set needs_price_update=True when price/currency changes
- Simplify Purchase.save() to remove DB reload + comparison logic
- Remove price_or_currency_differ_from() method
- Update convert_prices() to filter on needs_price_update flag
- Extract _get_exchange_rate() and _save_converted_price() helpers
- Add tests for the new behavior
* ignore English articles when sorting names
* added a new sort_name field that gets automatically created
* automatically fill certain values in forms:
* new game: name and sort name after typing
* new edition: name and sort name when selecting game
* new purchase: platform when selecting edition
lukas
