import 'package:drift/drift.dart';
import 'package:uto_manager/infrastructure/database/app_database.dart';

part 'personnel_dao.g.dart';

/// Data Access Object for [Personnel] table operations.
@DriftAccessor(tables: [Personnel])
class PersonnelDao extends DatabaseAccessor<AppDatabase> with _$PersonnelDaoMixin {
  PersonnelDao(super.db);

  /// Returns all personnel rows.
  Future<List<PersonnelData>> getAllPersonnel() => select(personnel).get();

  /// Returns the personnel record with [soldierId], or null if not found.
  Future<PersonnelData?> getPersonnelById(String soldierId) =>
      (select(personnel)..where((t) => t.soldierId.equals(soldierId))).getSingleOrNull();

  /// Returns all soldiers assigned to [slotId].
  Future<List<PersonnelData>> getBySlot(String slotId) =>
      (select(personnel)..where((t) => t.assignedSlotId.equals(slotId))).get();

  /// Returns all unassigned soldiers.
  Future<List<PersonnelData>> getUnassigned() =>
      (select(personnel)..where((t) => t.assignedSlotId.isNull())).get();

  /// Returns all soldiers with [primaryMos].
  Future<List<PersonnelData>> getByMos(String primaryMos) =>
      (select(personnel)..where((t) => t.primaryMos.equals(primaryMos))).get();

  /// Returns all soldiers at [payGrade].
  Future<List<PersonnelData>> getByPayGrade(String payGrade) =>
      (select(personnel)..where((t) => t.payGrade.equals(payGrade))).get();

  /// Inserts a new personnel row.
  Future<void> insertPersonnel(PersonnelCompanion entry) =>
      into(personnel).insert(entry, mode: InsertMode.insertOrFail);

  /// Inserts multiple personnel rows in a single transaction.
  Future<void> insertAllPersonnel(List<PersonnelCompanion> entries) =>
      batch((b) => b.insertAll(personnel, entries, mode: InsertMode.insertOrFail));

  /// Updates an existing personnel row.
  Future<bool> updatePersonnel(PersonnelCompanion entry) => update(personnel).replace(entry);

  /// Deletes the personnel record with [soldierId].
  Future<int> deletePersonnel(String soldierId) =>
      (delete(personnel)..where((t) => t.soldierId.equals(soldierId))).go();

  /// Assigns [soldierId] to [slotId].
  Future<void> assignToSlot(String soldierId, String slotId) async {
    await (update(personnel)..where((t) => t.soldierId.equals(soldierId))).write(
      PersonnelCompanion(assignedSlotId: Value(slotId)),
    );
  }

  /// Clears the slot assignment for [soldierId].
  Future<void> unassignFromSlot(String soldierId) async {
    await (update(personnel)..where((t) => t.soldierId.equals(soldierId))).write(
      const PersonnelCompanion(assignedSlotId: Value(null)),
    );
  }

  /// Deletes all personnel records.
  Future<int> deleteAllPersonnel() => delete(personnel).go();

  /// Returns a stream that emits all personnel whenever the table changes.
  Stream<List<PersonnelData>> watchAllPersonnel() => select(personnel).watch();

  /// Returns a stream that emits unassigned soldiers on changes.
  Stream<List<PersonnelData>> watchUnassigned() =>
      (select(personnel)..where((t) => t.assignedSlotId.isNull())).watch();
}