# Services Layer

Business logic extracted from routers for testability. Uses dependency injection.

## Architecture

- `interfaces.py` — Protocol classes (`AbstractPlayerRepository`, `AbstractTeamRepository`, `AbstractCacheService`)
- `base.py` — `BaseService` with lazy-loaded default repos (imports from `db_engine` on first access)
- `mocks.py` — Mock implementations for testing without DB/Redis
- `player_service.py`, `team_service.py` — Domain services (class methods, no instance needed for reads)

## Key Patterns

- Services use `@staticmethod`/`@classmethod` for read operations (no instantiation needed)
- Default repos are created lazily inside `@property` methods to avoid circular imports with `db_engine`
- For testing: pass mock repos via `ServiceConfig` or constructor kwargs
- Only `players` and `teams` routers currently use the service layer; others call `db_engine` directly