feat: creatives and external channels

src/usecase/creative/delete_creative.py

@@ -0,0 +1,23 @@
+import logging
+from typing import TYPE_CHECKING
+
+from src import domain, dto
+
+if TYPE_CHECKING:
+    from .. import Usecase
+
+log = logging.getLogger(__name__)
+
+
+async def delete_creative(self: 'Usecase', input: dto.DeleteCreativeInput) -> None:
+    async with self.database.transaction():
+        creative = await self.database.get_creative(input.user_id, input.creative_id)
+        if not creative:
+            log.warning('User %s attempted to delete unavailable creative %s', input.user_id, input.creative_id)
+            raise domain.CreativeNotFound(input.creative_id)
+
+        if creative.purchases_count > 0:
+            log.warning('Creative %s is used in purchases and cannot be deleted', input.creative_id)
+            raise domain.CreativeInUse(input.creative_id)
+
+        await self.database.delete_creative(input.creative_id)