Feature/ft categories on off authorization

[soraiayugulis]

Summary

Phase 2 of the ft-categories-on-off feature — authorization rule enforcement with category status checks. Implements Rule 4 (Category Active Check) and Rule 5 (Fallback Chain Skips Inactive Categories) from the specification.

Changes

Authorization Service

• AuthorizationService.java: Added category status check before balance check. If requested category is INACTIVE, returns CATEGORY_INACTIVE rejection reason without modifying balance.

Category Balance Checker

• CategoryBalanceChecker.java:
  • Changed signature from checkBalance(Map<Category, Balance>, Category, BigDecimal) to checkBalance(Card, Category, BigDecimal)
  • Added category status check for requested category (returns empty if INACTIVE)
  • Modified fallback loop to skip categories where getCategoryStatus(fallback) == INACTIVE
  • Added private getBalances(Card) helper method

Tests

• AuthorizationServiceTest.java:

  • Added test for category inactive check (TC-007): transaction denied with CATEGORY_INACTIVE when category is inactive, balance unchanged
  • Added test for active category (TC-008): transaction proceeds to balance check when category is active
  • Added test for MEAL fallback skipping inactive FOOD (TC-014): FOOD skipped when inactive, GENERAL used instead

• CategoryBalanceCheckerTest.java:

  • Updated all tests to use Card instead of Map<Category, Balance>
  • All existing tests continue to pass with new signature

Notes

• TDD Approach: All changes followed red-green-refactor cycle
• Signature Change: CategoryBalanceChecker.checkBalance now receives Card instead of balances map to enable category status checks
• Fallback Behavior: MEAL fallback chain now skips inactive categories; if all fallback categories are inactive, transaction is denied with INSUFFICIENT_BALANCE
• No Balance Modification: When category is inactive, balance is not modified (verified in test)
• All Tests Pass: 138 tests passing

Checklist

• Category status check enforced before balance check in AuthorizationService
• CategoryBalanceChecker modified to receive Card and check category status
• Fallback loop skips inactive categories
• Test for category inactive check (TC-007)
• Test for active category proceeding to balance check (TC-008)
• Test for MEAL fallback skipping inactive FOOD (TC-014)
• All 138 tests passing