// Application orchestration contracts for UI-facing use cases.
//
// This layer sits above the pure domain services and repository interfaces. It
// gives future Flutter/use-case code one atomic boundary per user command
// without importing widgets, MongoDB clients, or platform notification APIs.

import 'backlog.dart';
import 'locked_time.dart';
import 'models.dart';
import 'project_statistics.dart';
import 'repositories.dart';
import 'scheduling_engine.dart';
import 'task_lifecycle.dart';
import 'time_contracts.dart';

/// Owner-local time context supplied to application operations.
class OwnerTimeZoneContext {
  OwnerTimeZoneContext({
    required String ownerId,
    required String timeZoneId,
  })  : ownerId = _requiredTrimmed(ownerId, 'ownerId'),
        timeZoneId = _requiredTrimmed(timeZoneId, 'timeZoneId');

  /// Authorization-neutral owner scope. V1 does not implement accounts.
  final String ownerId;

  /// IANA-style time-zone identifier chosen by the app boundary.
  final String timeZoneId;
}

/// Per-operation application context.
class ApplicationOperationContext {
  ApplicationOperationContext({
    required String operationId,
    required this.now,
    required this.ownerTimeZone,
    required this.clock,
    required this.idGenerator,
  }) : operationId = _requiredTrimmed(operationId, 'operationId');

  /// Convenience constructor that captures [Clock.now] once.
  factory ApplicationOperationContext.start({
    required String operationId,
    required OwnerTimeZoneContext ownerTimeZone,
    required Clock clock,
    required IdGenerator idGenerator,
  }) {
    return ApplicationOperationContext(
      operationId: operationId,
      now: clock.now(),
      ownerTimeZone: ownerTimeZone,
      clock: clock,
      idGenerator: idGenerator,
    );
  }

  /// Exactly-once key for this user command.
  final String operationId;

  /// Instant used by the operation. Use this instead of repeatedly reading the
  /// clock during one command.
  final DateTime now;

  /// Owner scope and time-zone data for date-sensitive rules.
  final OwnerTimeZoneContext ownerTimeZone;

  /// Injected clock available to lower-level services that need one.
  final Clock clock;

  /// Injected ID generator for records created by the operation.
  final IdGenerator idGenerator;
}

/// Stable application-layer result categories.
enum ApplicationFailureCode {
  validation,
  notFound,
  conflict,
  staleRevision,
  noSlot,
  duplicateOperation,
  persistenceFailure,
  unexpected,
}

/// Typed failure returned by application commands and queries.
class ApplicationFailure {
  const ApplicationFailure({
    required this.code,
    this.entityId,
    this.detailCode,
  });

  /// Stable machine-readable category.
  final ApplicationFailureCode code;

  /// Optional stable entity id related to the failure.
  final String? entityId;

  /// Optional narrower stable reason, such as a domain validation code name.
  final String? detailCode;
}

/// Result wrapper for expected application success/failure paths.
class ApplicationResult<T> {
  const ApplicationResult._({
    this.value,
    this.failure,
  });

  /// Successful result carrying [value].
  factory ApplicationResult.success(T value) {
    return ApplicationResult._(value: value);
  }

  /// Expected failure result.
  factory ApplicationResult.failure(ApplicationFailure failure) {
    return ApplicationResult._(failure: failure);
  }

  /// Successful value, if any.
  final T? value;

  /// Typed failure, if the operation did not succeed.
  final ApplicationFailure? failure;

  /// Whether the operation succeeded.
  bool get isSuccess => failure == null;

  /// Whether the operation failed with a typed application failure.
  bool get isFailure => failure != null;

  /// Return the value or throw if this result is a failure.
  T get requireValue {
    if (failure != null) {
      throw StateError(
          'Application result is a failure: ${failure!.code.name}');
    }
    return value as T;
  }
}

/// Exception for expected failures raised inside a unit-of-work callback.
class ApplicationFailureException implements Exception {
  const ApplicationFailureException(this.failure);

  /// Failure to return from the application boundary.
  final ApplicationFailure failure;
}

/// Exception representing persistence/driver failures at repository boundaries.
class ApplicationPersistenceException implements Exception {
  const ApplicationPersistenceException();
}

/// Persisted exactly-once operation record.
class ApplicationOperationRecord {
  ApplicationOperationRecord({
    required String operationId,
    required String ownerId,
    required String operationName,
    required this.committedAt,
  })  : operationId = _requiredTrimmed(operationId, 'operationId'),
        ownerId = _requiredTrimmed(ownerId, 'ownerId'),
        operationName = _requiredTrimmed(operationName, 'operationName');

  /// Exactly-once operation id.
  final String operationId;

  /// Authorization-neutral owner scope.
  final String ownerId;

  /// Stable use-case/command label.
  final String operationName;

  /// Commit instant.
  final DateTime committedAt;
}

/// Owner-scoped acknowledgement for a one-time scheduling notice.
class NoticeAcknowledgementRecord {
  NoticeAcknowledgementRecord({
    required String noticeId,
    required String ownerId,
    required this.acknowledgedAt,
  })  : noticeId = _requiredTrimmed(noticeId, 'noticeId'),
        ownerId = _requiredTrimmed(ownerId, 'ownerId');

  /// Stable notice id generated by the read/use-case boundary.
  final String noticeId;

  /// Authorization-neutral owner scope.
  final String ownerId;

  /// Instant the notice was consumed.
  final DateTime acknowledgedAt;
}

/// Owner-level settings needed by application use cases.
class OwnerSettings {
  OwnerSettings({
    required String ownerId,
    required String timeZoneId,
    WallTime? dayStart,
    WallTime? dayEnd,
    this.compactModeEnabled = false,
    this.backlogStalenessSettings = const BacklogStalenessSettings(),
  })  : ownerId = _requiredTrimmed(ownerId, 'ownerId'),
        timeZoneId = _requiredTrimmed(timeZoneId, 'timeZoneId'),
        dayStart = dayStart ?? WallTime(hour: 0, minute: 0),
        dayEnd = dayEnd ?? WallTime(hour: 23, minute: 59) {
    if (this.dayStart.compareTo(this.dayEnd) >= 0) {
      throw ArgumentError.value(
        {'dayStart': this.dayStart, 'dayEnd': this.dayEnd},
        'dayEnd',
        'Day end must be after day start.',
      );
    }
  }

  /// Authorization-neutral owner scope.
  final String ownerId;

  /// Owner time-zone id used by date-sensitive application use cases.
  final String timeZoneId;

  /// Default local day start.
  final WallTime dayStart;

  /// Default local day end.
  final WallTime dayEnd;

  /// Persisted compact-mode preference.
  final bool compactModeEnabled;

  /// Configurable backlog age thresholds.
  final BacklogStalenessSettings backlogStalenessSettings;

  /// Return a copy with selected settings changed.
  OwnerSettings copyWith({
    String? ownerId,
    String? timeZoneId,
    WallTime? dayStart,
    WallTime? dayEnd,
    bool? compactModeEnabled,
    BacklogStalenessSettings? backlogStalenessSettings,
  }) {
    return OwnerSettings(
      ownerId: ownerId ?? this.ownerId,
      timeZoneId: timeZoneId ?? this.timeZoneId,
      dayStart: dayStart ?? this.dayStart,
      dayEnd: dayEnd ?? this.dayEnd,
      compactModeEnabled: compactModeEnabled ?? this.compactModeEnabled,
      backlogStalenessSettings:
          backlogStalenessSettings ?? this.backlogStalenessSettings,
    );
  }
}

/// Repository contract for internal task activities.
abstract interface class TaskActivityRepository {
  Future<TaskActivity?> findById(String id);

  Future<List<TaskActivity>> findByOperationId(String operationId);

  Future<List<TaskActivity>> findByTaskId(String taskId);

  Future<List<TaskActivity>> findAll();

  Future<void> save(TaskActivity activity);

  Future<void> saveAll(Iterable<TaskActivity> activities);
}

/// Repository contract for project statistics aggregates.
abstract interface class ProjectStatisticsRepository {
  Future<ProjectStatistics?> findByProjectId(String projectId);

  Future<List<ProjectStatistics>> findAll();

  Future<void> save(ProjectStatistics statistics);
}

/// Repository contract for owner settings.
abstract interface class OwnerSettingsRepository {
  Future<OwnerSettings?> findByOwnerId(String ownerId);

  Future<void> save(OwnerSettings settings);
}

/// Repository contract for consumed one-time notices.
abstract interface class NoticeAcknowledgementRepository {
  Future<NoticeAcknowledgementRecord?> findById({
    required String ownerId,
    required String noticeId,
  });

  Future<List<NoticeAcknowledgementRecord>> findByOwnerId(String ownerId);

  Future<void> save(NoticeAcknowledgementRecord record);
}

/// Repository contract for exactly-once operation records.
abstract interface class ApplicationOperationRepository {
  Future<ApplicationOperationRecord?> findById(String operationId);

  Future<void> save(ApplicationOperationRecord operation);
}

/// Repository set available inside one application unit of work.
abstract interface class ApplicationUnitOfWorkRepositories {
  TaskRepository get tasks;

  ProjectRepository get projects;

  LockedBlockRepository get lockedBlocks;

  SchedulingSnapshotRepository get schedulingSnapshots;

  TaskActivityRepository get taskActivities;

  ProjectStatisticsRepository get projectStatistics;

  OwnerSettingsRepository get ownerSettings;

  NoticeAcknowledgementRepository get noticeAcknowledgements;

  ApplicationOperationRepository get operations;
}

/// Atomic application transaction boundary.
abstract interface class ApplicationUnitOfWork {
  Future<ApplicationResult<T>> run<T>({
    required ApplicationOperationContext context,
    required String operationName,
    required Future<ApplicationResult<T>> Function(
      ApplicationUnitOfWorkRepositories repositories,
    ) action,
  });

  Future<ApplicationResult<T>> read<T>({
    required Future<ApplicationResult<T>> Function(
      ApplicationUnitOfWorkRepositories repositories,
    ) action,
  });
}

/// Repository loader for common scheduler input assembly.
class ApplicationSchedulingLoader {
  const ApplicationSchedulingLoader(this.repositories);

  /// Repositories for the current application operation.
  final ApplicationUnitOfWorkRepositories repositories;

  /// Load scheduler input for [window] from the repository boundary.
  ///
  /// UI code should not persist partial [SchedulingResult] objects. Commands
  /// should load authoritative state here, invoke domain services, then commit
  /// resulting entities through a unit of work.
  Future<SchedulingInput> loadInputForWindow({
    required SchedulingWindow window,
    List<TimeInterval> lockedIntervals = const <TimeInterval>[],
    List<TimeInterval> requiredVisibleIntervals = const <TimeInterval>[],
  }) async {
    final scheduledTasks = await repositories.tasks.findScheduledInWindow(
      window,
    );
    return SchedulingInput(
      tasks: scheduledTasks,
      window: window,
      lockedIntervals: lockedIntervals,
      requiredVisibleIntervals: requiredVisibleIntervals,
    );
  }
}

/// In-memory unit-of-work implementation for deterministic application tests.
class InMemoryApplicationUnitOfWork implements ApplicationUnitOfWork {
  InMemoryApplicationUnitOfWork({
    Iterable<Task> initialTasks = const <Task>[],
    Iterable<ProjectProfile> initialProjects = const <ProjectProfile>[],
    Iterable<LockedBlock> initialLockedBlocks = const <LockedBlock>[],
    Iterable<LockedBlockOverride> initialLockedOverrides =
        const <LockedBlockOverride>[],
    Iterable<SchedulingStateSnapshot> initialSchedulingSnapshots =
        const <SchedulingStateSnapshot>[],
    Iterable<TaskActivity> initialTaskActivities = const <TaskActivity>[],
    Iterable<ProjectStatistics> initialProjectStatistics =
        const <ProjectStatistics>[],
    Iterable<OwnerSettings> initialOwnerSettings = const <OwnerSettings>[],
    Iterable<NoticeAcknowledgementRecord> initialNoticeAcknowledgements =
        const <NoticeAcknowledgementRecord>[],
    Iterable<ApplicationOperationRecord> initialOperations =
        const <ApplicationOperationRecord>[],
  }) : _state = _InMemoryApplicationState(
          tasksById: {
            for (final task in initialTasks) task.id: task,
          },
          projectsById: {
            for (final project in initialProjects) project.id: project,
          },
          lockedBlocksById: {
            for (final block in initialLockedBlocks) block.id: block,
          },
          lockedOverridesById: {
            for (final override in initialLockedOverrides)
              override.id: override,
          },
          schedulingSnapshotsById: {
            for (final snapshot in initialSchedulingSnapshots)
              snapshot.id: snapshot,
          },
          taskActivitiesById: {
            for (final activity in initialTaskActivities) activity.id: activity,
          },
          projectStatisticsByProjectId: {
            for (final statistics in initialProjectStatistics)
              statistics.projectId: statistics,
          },
          ownerSettingsByOwnerId: {
            for (final settings in initialOwnerSettings)
              settings.ownerId: settings,
          },
          noticeAcknowledgementsByScopedId: {
            for (final acknowledgement in initialNoticeAcknowledgements)
              _noticeAcknowledgementKey(
                ownerId: acknowledgement.ownerId,
                noticeId: acknowledgement.noticeId,
              ): acknowledgement,
          },
          operationsById: {
            for (final operation in initialOperations)
              operation.operationId: operation,
          },
        );

  _InMemoryApplicationState _state;
  bool _failNextCommit = false;

  /// Current committed tasks, useful for contract tests.
  List<Task> get currentTasks =>
      List<Task>.unmodifiable(_state.tasksById.values);

  /// Current committed projects, useful for contract tests.
  List<ProjectProfile> get currentProjects {
    return List<ProjectProfile>.unmodifiable(_state.projectsById.values);
  }

  /// Current committed locked blocks, useful for contract tests.
  List<LockedBlock> get currentLockedBlocks {
    return List<LockedBlock>.unmodifiable(_state.lockedBlocksById.values);
  }

  /// Current committed locked overrides, useful for contract tests.
  List<LockedBlockOverride> get currentLockedOverrides {
    return List<LockedBlockOverride>.unmodifiable(
      _state.lockedOverridesById.values,
    );
  }

  /// Current committed scheduling snapshots, useful for contract tests.
  List<SchedulingStateSnapshot> get currentSchedulingSnapshots {
    return List<SchedulingStateSnapshot>.unmodifiable(
      _state.schedulingSnapshotsById.values,
    );
  }

  /// Current committed activities, useful for contract tests.
  List<TaskActivity> get currentTaskActivities {
    return List<TaskActivity>.unmodifiable(_state.taskActivitiesById.values);
  }

  /// Current committed project statistics, useful for contract tests.
  List<ProjectStatistics> get currentProjectStatistics {
    return List<ProjectStatistics>.unmodifiable(
      _state.projectStatisticsByProjectId.values,
    );
  }

  /// Current committed owner settings, useful for contract tests.
  List<OwnerSettings> get currentOwnerSettings {
    return List<OwnerSettings>.unmodifiable(
        _state.ownerSettingsByOwnerId.values);
  }

  /// Current committed notice acknowledgements, useful for contract tests.
  List<NoticeAcknowledgementRecord> get currentNoticeAcknowledgements {
    return List<NoticeAcknowledgementRecord>.unmodifiable(
      _state.noticeAcknowledgementsByScopedId.values,
    );
  }

  /// Current committed operation records, useful for contract tests.
  List<ApplicationOperationRecord> get currentOperations {
    return List<ApplicationOperationRecord>.unmodifiable(
      _state.operationsById.values,
    );
  }

  /// Cause the next successful transaction to fail at commit time.
  void failNextCommitForTesting() {
    _failNextCommit = true;
  }

  @override
  Future<ApplicationResult<T>> run<T>({
    required ApplicationOperationContext context,
    required String operationName,
    required Future<ApplicationResult<T>> Function(
      ApplicationUnitOfWorkRepositories repositories,
    ) action,
  }) async {
    if (_state.operationsById.containsKey(context.operationId)) {
      return ApplicationResult.failure(
        ApplicationFailure(
          code: ApplicationFailureCode.duplicateOperation,
          entityId: context.operationId,
        ),
      );
    }

    final staged = _state.copy();
    final repositories = _InMemoryApplicationRepositories(staged);

    try {
      final result = await action(repositories);
      if (result.isFailure) {
        return result;
      }

      staged.operationsById[context.operationId] = ApplicationOperationRecord(
        operationId: context.operationId,
        ownerId: context.ownerTimeZone.ownerId,
        operationName: operationName,
        committedAt: context.now,
      );

      if (_failNextCommit) {
        _failNextCommit = false;
        throw const ApplicationPersistenceException();
      }

      _state = staged;
      return result;
    } on ApplicationFailureException catch (error) {
      return ApplicationResult.failure(error.failure);
    } on DomainValidationException catch (error) {
      return ApplicationResult.failure(
        ApplicationFailure(
          code: ApplicationFailureCode.validation,
          detailCode: error.code.name,
        ),
      );
    } on ArgumentError catch (error) {
      return ApplicationResult.failure(
        ApplicationFailure(
          code: ApplicationFailureCode.validation,
          detailCode: error.name,
        ),
      );
    } on ApplicationPersistenceException {
      return ApplicationResult.failure(
        const ApplicationFailure(
          code: ApplicationFailureCode.persistenceFailure,
        ),
      );
    } catch (_) {
      return ApplicationResult.failure(
        const ApplicationFailure(code: ApplicationFailureCode.unexpected),
      );
    }
  }

  @override
  Future<ApplicationResult<T>> read<T>({
    required Future<ApplicationResult<T>> Function(
      ApplicationUnitOfWorkRepositories repositories,
    ) action,
  }) async {
    final staged = _state.copy();
    final repositories = _InMemoryApplicationRepositories(staged);

    try {
      return await action(repositories);
    } on ApplicationFailureException catch (error) {
      return ApplicationResult.failure(error.failure);
    } on DomainValidationException catch (error) {
      return ApplicationResult.failure(
        ApplicationFailure(
          code: ApplicationFailureCode.validation,
          detailCode: error.code.name,
        ),
      );
    } on ArgumentError catch (error) {
      return ApplicationResult.failure(
        ApplicationFailure(
          code: ApplicationFailureCode.validation,
          detailCode: error.name,
        ),
      );
    } on ApplicationPersistenceException {
      return ApplicationResult.failure(
        const ApplicationFailure(
          code: ApplicationFailureCode.persistenceFailure,
        ),
      );
    } catch (_) {
      return ApplicationResult.failure(
        const ApplicationFailure(code: ApplicationFailureCode.unexpected),
      );
    }
  }
}

class _InMemoryApplicationState {
  _InMemoryApplicationState({
    required this.tasksById,
    required this.projectsById,
    required this.lockedBlocksById,
    required this.lockedOverridesById,
    required this.schedulingSnapshotsById,
    required this.taskActivitiesById,
    required this.projectStatisticsByProjectId,
    required this.ownerSettingsByOwnerId,
    required this.noticeAcknowledgementsByScopedId,
    required this.operationsById,
  });

  final Map<String, Task> tasksById;
  final Map<String, ProjectProfile> projectsById;
  final Map<String, LockedBlock> lockedBlocksById;
  final Map<String, LockedBlockOverride> lockedOverridesById;
  final Map<String, SchedulingStateSnapshot> schedulingSnapshotsById;
  final Map<String, TaskActivity> taskActivitiesById;
  final Map<String, ProjectStatistics> projectStatisticsByProjectId;
  final Map<String, OwnerSettings> ownerSettingsByOwnerId;
  final Map<String, NoticeAcknowledgementRecord>
      noticeAcknowledgementsByScopedId;
  final Map<String, ApplicationOperationRecord> operationsById;

  _InMemoryApplicationState copy() {
    return _InMemoryApplicationState(
      tasksById: Map<String, Task>.of(tasksById),
      projectsById: Map<String, ProjectProfile>.of(projectsById),
      lockedBlocksById: Map<String, LockedBlock>.of(lockedBlocksById),
      lockedOverridesById:
          Map<String, LockedBlockOverride>.of(lockedOverridesById),
      schedulingSnapshotsById:
          Map<String, SchedulingStateSnapshot>.of(schedulingSnapshotsById),
      taskActivitiesById: Map<String, TaskActivity>.of(taskActivitiesById),
      projectStatisticsByProjectId:
          Map<String, ProjectStatistics>.of(projectStatisticsByProjectId),
      ownerSettingsByOwnerId: Map<String, OwnerSettings>.of(
        ownerSettingsByOwnerId,
      ),
      noticeAcknowledgementsByScopedId:
          Map<String, NoticeAcknowledgementRecord>.of(
        noticeAcknowledgementsByScopedId,
      ),
      operationsById: Map<String, ApplicationOperationRecord>.of(
        operationsById,
      ),
    );
  }
}

class _InMemoryApplicationRepositories
    implements ApplicationUnitOfWorkRepositories {
  _InMemoryApplicationRepositories(_InMemoryApplicationState state)
      : tasks = _UnitOfWorkTaskRepository(state.tasksById),
        projects = _UnitOfWorkProjectRepository(state.projectsById),
        lockedBlocks = _UnitOfWorkLockedBlockRepository(
          blocksById: state.lockedBlocksById,
          overridesById: state.lockedOverridesById,
        ),
        schedulingSnapshots = _UnitOfWorkSchedulingSnapshotRepository(
          state.schedulingSnapshotsById,
        ),
        taskActivities = _UnitOfWorkTaskActivityRepository(
          state.taskActivitiesById,
        ),
        projectStatistics = _UnitOfWorkProjectStatisticsRepository(
          state.projectStatisticsByProjectId,
        ),
        ownerSettings = _UnitOfWorkOwnerSettingsRepository(
          state.ownerSettingsByOwnerId,
        ),
        noticeAcknowledgements = _UnitOfWorkNoticeAcknowledgementRepository(
          state.noticeAcknowledgementsByScopedId,
        ),
        operations = _UnitOfWorkOperationRepository(state.operationsById);

  @override
  final TaskRepository tasks;

  @override
  final ProjectRepository projects;

  @override
  final LockedBlockRepository lockedBlocks;

  @override
  final SchedulingSnapshotRepository schedulingSnapshots;

  @override
  final TaskActivityRepository taskActivities;

  @override
  final ProjectStatisticsRepository projectStatistics;

  @override
  final OwnerSettingsRepository ownerSettings;

  @override
  final NoticeAcknowledgementRepository noticeAcknowledgements;

  @override
  final ApplicationOperationRepository operations;
}

class _UnitOfWorkTaskRepository implements TaskRepository {
  _UnitOfWorkTaskRepository(this._tasksById);

  final Map<String, Task> _tasksById;

  @override
  Future<Task?> findById(String id) async => _tasksById[id];

  @override
  Future<List<Task>> findAll() async {
    return List<Task>.unmodifiable(_tasksById.values);
  }

  @override
  Future<List<Task>> findByStatus(TaskStatus status) async {
    return List<Task>.unmodifiable(
      _tasksById.values.where((task) => task.status == status),
    );
  }

  @override
  Future<List<Task>> findScheduledInWindow(SchedulingWindow window) async {
    return List<Task>.unmodifiable(
      _tasksById.values.where((task) {
        final start = task.scheduledStart;
        final end = task.scheduledEnd;
        if (start == null || end == null) {
          return false;
        }
        return TimeInterval(start: start, end: end).overlaps(window.interval);
      }),
    );
  }

  @override
  Future<void> save(Task task) async {
    _tasksById[task.id] = task;
  }

  @override
  Future<void> saveAll(Iterable<Task> tasks) async {
    for (final task in tasks) {
      _tasksById[task.id] = task;
    }
  }
}

class _UnitOfWorkProjectRepository implements ProjectRepository {
  _UnitOfWorkProjectRepository(this._projectsById);

  final Map<String, ProjectProfile> _projectsById;

  @override
  Future<ProjectProfile?> findById(String id) async => _projectsById[id];

  @override
  Future<List<ProjectProfile>> findAll() async {
    return List<ProjectProfile>.unmodifiable(_projectsById.values);
  }

  @override
  Future<void> save(ProjectProfile project) async {
    _projectsById[project.id] = project;
  }
}

class _UnitOfWorkLockedBlockRepository implements LockedBlockRepository {
  _UnitOfWorkLockedBlockRepository({
    required Map<String, LockedBlock> blocksById,
    required Map<String, LockedBlockOverride> overridesById,
  })  : _blocksById = blocksById,
        _overridesById = overridesById;

  final Map<String, LockedBlock> _blocksById;
  final Map<String, LockedBlockOverride> _overridesById;

  @override
  Future<LockedBlock?> findBlockById(String id) async => _blocksById[id];

  @override
  Future<List<LockedBlock>> findAllBlocks() async {
    return List<LockedBlock>.unmodifiable(_blocksById.values);
  }

  @override
  Future<LockedBlockOverride?> findOverrideById(String id) async {
    return _overridesById[id];
  }

  @override
  Future<List<LockedBlockOverride>> findAllOverrides() async {
    return List<LockedBlockOverride>.unmodifiable(_overridesById.values);
  }

  @override
  Future<void> saveBlock(LockedBlock block) async {
    _blocksById[block.id] = block;
  }

  @override
  Future<void> saveOverride(LockedBlockOverride override) async {
    _overridesById[override.id] = override;
  }
}

class _UnitOfWorkSchedulingSnapshotRepository
    implements SchedulingSnapshotRepository {
  _UnitOfWorkSchedulingSnapshotRepository(this._snapshotsById);

  final Map<String, SchedulingStateSnapshot> _snapshotsById;

  @override
  Future<SchedulingStateSnapshot?> findById(String id) async {
    return _snapshotsById[id];
  }

  @override
  Future<List<SchedulingStateSnapshot>> findInWindow(
    SchedulingWindow window,
  ) async {
    return List<SchedulingStateSnapshot>.unmodifiable(
      _snapshotsById.values.where(
        (snapshot) => snapshot.window.interval.overlaps(window.interval),
      ),
    );
  }

  @override
  Future<void> save(SchedulingStateSnapshot snapshot) async {
    _snapshotsById[snapshot.id] = snapshot;
  }
}

class _UnitOfWorkTaskActivityRepository implements TaskActivityRepository {
  _UnitOfWorkTaskActivityRepository(this._activitiesById);

  final Map<String, TaskActivity> _activitiesById;

  @override
  Future<TaskActivity?> findById(String id) async => _activitiesById[id];

  @override
  Future<List<TaskActivity>> findByOperationId(String operationId) async {
    return List<TaskActivity>.unmodifiable(
      _activitiesById.values.where(
        (activity) => activity.operationId == operationId,
      ),
    );
  }

  @override
  Future<List<TaskActivity>> findByTaskId(String taskId) async {
    return List<TaskActivity>.unmodifiable(
      _activitiesById.values.where((activity) => activity.taskId == taskId),
    );
  }

  @override
  Future<List<TaskActivity>> findAll() async {
    return List<TaskActivity>.unmodifiable(_activitiesById.values);
  }

  @override
  Future<void> save(TaskActivity activity) async {
    _activitiesById[activity.id] = activity;
  }

  @override
  Future<void> saveAll(Iterable<TaskActivity> activities) async {
    for (final activity in activities) {
      _activitiesById[activity.id] = activity;
    }
  }
}

class _UnitOfWorkProjectStatisticsRepository
    implements ProjectStatisticsRepository {
  _UnitOfWorkProjectStatisticsRepository(this._statisticsByProjectId);

  final Map<String, ProjectStatistics> _statisticsByProjectId;

  @override
  Future<ProjectStatistics?> findByProjectId(String projectId) async {
    return _statisticsByProjectId[projectId];
  }

  @override
  Future<List<ProjectStatistics>> findAll() async {
    return List<ProjectStatistics>.unmodifiable(_statisticsByProjectId.values);
  }

  @override
  Future<void> save(ProjectStatistics statistics) async {
    _statisticsByProjectId[statistics.projectId] = statistics;
  }
}

class _UnitOfWorkOwnerSettingsRepository implements OwnerSettingsRepository {
  _UnitOfWorkOwnerSettingsRepository(this._settingsByOwnerId);

  final Map<String, OwnerSettings> _settingsByOwnerId;

  @override
  Future<OwnerSettings?> findByOwnerId(String ownerId) async {
    return _settingsByOwnerId[ownerId];
  }

  @override
  Future<void> save(OwnerSettings settings) async {
    _settingsByOwnerId[settings.ownerId] = settings;
  }
}

class _UnitOfWorkNoticeAcknowledgementRepository
    implements NoticeAcknowledgementRepository {
  _UnitOfWorkNoticeAcknowledgementRepository(this._recordsByScopedId);

  final Map<String, NoticeAcknowledgementRecord> _recordsByScopedId;

  @override
  Future<NoticeAcknowledgementRecord?> findById({
    required String ownerId,
    required String noticeId,
  }) async {
    return _recordsByScopedId[
        _noticeAcknowledgementKey(ownerId: ownerId, noticeId: noticeId)];
  }

  @override
  Future<List<NoticeAcknowledgementRecord>> findByOwnerId(
    String ownerId,
  ) async {
    return List<NoticeAcknowledgementRecord>.unmodifiable(
      _recordsByScopedId.values.where((record) => record.ownerId == ownerId),
    );
  }

  @override
  Future<void> save(NoticeAcknowledgementRecord record) async {
    _recordsByScopedId[_noticeAcknowledgementKey(
      ownerId: record.ownerId,
      noticeId: record.noticeId,
    )] = record;
  }
}

class _UnitOfWorkOperationRepository implements ApplicationOperationRepository {
  _UnitOfWorkOperationRepository(this._operationsById);

  final Map<String, ApplicationOperationRecord> _operationsById;

  @override
  Future<ApplicationOperationRecord?> findById(String operationId) async {
    return _operationsById[operationId];
  }

  @override
  Future<void> save(ApplicationOperationRecord operation) async {
    _operationsById[operation.operationId] = operation;
  }
}

String _noticeAcknowledgementKey({
  required String ownerId,
  required String noticeId,
}) {
  return '$ownerId::$noticeId';
}

String _requiredTrimmed(String value, String name) {
  final trimmed = value.trim();
  if (trimmed.isEmpty) {
    throw ArgumentError.value(value, name, 'Value is required.');
  }
  return trimmed;
}