import 'package:uto_manager/domain/entities/authorized_rank.dart';
import 'package:uto_manager/domain/entities/personnel_record.dart';
import 'package:uto_manager/domain/value_objects/duty_mos.dart';

/// Abstract repository interface for [PersonnelRecord] persistence operations.
///
/// Implementations are provided by the infrastructure layer. The domain layer
/// depends only on this interface, never on concrete implementations.
abstract interface class PersonnelRepository {
  /// Returns all personnel records in the database.
  Future<List<PersonnelRecord>> getAll();

  /// Returns the personnel record with [soldierId], or null if not found.
  Future<PersonnelRecord?> getById(String soldierId);

  /// Returns all soldiers assigned to the slot with [slotId].
  Future<List<PersonnelRecord>> getBySlot(String slotId);

  /// Returns all unassigned soldiers (not assigned to any slot).
  Future<List<PersonnelRecord>> getUnassigned();

  /// Returns all soldiers with the given [primaryMos].
  Future<List<PersonnelRecord>> getByMos(DutyMos primaryMos);

  /// Returns all soldiers at the given [payGrade].
  Future<List<PersonnelRecord>> getByPayGrade(AuthorizedRank payGrade);

  /// Inserts a new [record] into the repository.
  ///
  /// Throws [StateError] if a record with the same soldier ID already exists.
  Future<void> insert(PersonnelRecord record);

  /// Inserts multiple [records] in a single atomic transaction.
  Future<void> insertAll(List<PersonnelRecord> records);

  /// Updates an existing [record] in the repository.
  ///
  /// Throws [StateError] if no record with the given soldier ID exists.
  Future<void> update(PersonnelRecord record);

  /// Deletes the personnel record with [soldierId].
  Future<void> delete(String soldierId);

  /// Assigns the soldier with [soldierId] to the slot with [slotId].
  ///
  /// Clears any previous slot assignment for this soldier.
  Future<void> assignToSlot(String soldierId, String slotId);

  /// Removes the slot assignment for the soldier with [soldierId].
  Future<void> unassignFromSlot(String soldierId);

  /// Returns a stream that emits the full personnel list whenever it changes.
  Stream<List<PersonnelRecord>> watchAll();

  /// Returns a stream that emits unassigned soldiers whenever the list changes.
  Stream<List<PersonnelRecord>> watchUnassigned();

  /// Deletes all personnel records from the repository.
  Future<void> deleteAll();
}