GameTime/lib/application/use_cases.dart

import 'dart:convert';

import '../domain/domain.dart';
import 'ports.dart';

final class ExerciseUseCases {
  const ExerciseUseCases({
    required this.repository,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final ExerciseRepository repository;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<Exercise> create({
    required String name,
    String? description,
    String? imageMediaId,
    String? videoMediaId,
    required bool hasTimeMeasure,
    required bool hasRepsMeasure,
    required bool hasScoreMeasure,
    String? scoreLabel,
    String? scoreUnit,
  }) async {
    final now = clock.now();
    final exercise = Exercise(
      metadata: _newMetadata(ids, originDeviceId, now),
      name: name,
      description: description,
      imageMediaId: imageMediaId,
      videoMediaId: videoMediaId,
      hasTimeMeasure: hasTimeMeasure,
      hasRepsMeasure: hasRepsMeasure,
      hasScoreMeasure: hasScoreMeasure,
      scoreLabel: scoreLabel,
      scoreUnit: scoreUnit,
    );
    await repository.save(exercise);
    return exercise;
  }

  Future<void> save(Exercise exercise) => repository.save(exercise);

  Future<List<Exercise>> listActive() => repository.listActive();

  Future<bool> isUsedInPrograms(String id) {
    return repository.isReferencedByProgram(id);
  }

  Future<Exercise> update({
    required String id,
    required String name,
    String? description,
    String? imageMediaId,
    String? videoMediaId,
    required bool hasTimeMeasure,
    required bool hasRepsMeasure,
    required bool hasScoreMeasure,
    String? scoreLabel,
    String? scoreUnit,
  }) async {
    final exercise = await repository.findById(id);
    if (exercise == null) {
      throw const DomainException('Exercise not found.');
    }
    final updated = exercise.copyWith(
      metadata: exercise.metadata.touch(clock.now()),
      name: name,
      description: description,
      imageMediaId: imageMediaId,
      videoMediaId: videoMediaId,
      hasTimeMeasure: hasTimeMeasure,
      hasRepsMeasure: hasRepsMeasure,
      hasScoreMeasure: hasScoreMeasure,
      scoreLabel: scoreLabel,
      scoreUnit: scoreUnit,
    );
    await repository.save(updated);
    return updated;
  }

  Future<Exercise> attachImage({
    required String exerciseId,
    required String mediaAssetId,
  }) async {
    final exercise = await repository.findById(exerciseId);
    if (exercise == null) {
      throw const DomainException('Exercise not found.');
    }
    final updated = exercise.copyWith(
      imageMediaId: mediaAssetId,
      metadata: exercise.metadata.touch(clock.now()),
    );
    await repository.save(updated);
    return updated;
  }

  Future<Exercise> attachVideo({
    required String exerciseId,
    required String mediaAssetId,
  }) async {
    final exercise = await repository.findById(exerciseId);
    if (exercise == null) {
      throw const DomainException('Exercise not found.');
    }
    final updated = exercise.copyWith(
      videoMediaId: mediaAssetId,
      metadata: exercise.metadata.touch(clock.now()),
    );
    await repository.save(updated);
    return updated;
  }

  Future<Exercise> archive(String id) async {
    final exercise = await repository.findById(id);
    if (exercise == null) {
      throw const DomainException('Exercise not found.');
    }
    final archived = exercise.archive(clock.now());
    await repository.save(archived);
    return archived;
  }
}

final class MediaUseCases {
  const MediaUseCases({
    required this.mediaRepository,
    required this.exerciseRepository,
    required this.storage,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final MediaAssetRepository mediaRepository;
  final ExerciseRepository exerciseRepository;
  final LocalMediaStorage storage;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<MediaAsset> importMedia({
    required String sourcePath,
    required MediaKind kind,
  }) async {
    final now = clock.now();
    final id = ids.newId();
    final stored = await storage.importFile(
      sourcePath: sourcePath,
      kind: kind,
      stableFileName: id,
    );
    final asset = MediaAsset(
      metadata: EntityMetadata(
        id: id,
        createdAt: now,
        updatedAt: now,
        originDeviceId: originDeviceId,
      ),
      kind: kind,
      localUri: stored.localUri,
      mimeType: stored.mimeType,
      sizeBytes: stored.sizeBytes,
      width: stored.width,
      height: stored.height,
      durationMs: stored.durationMs,
    );
    await mediaRepository.save(asset);
    return asset;
  }

  Future<Exercise> attachToExercise({
    required String exerciseId,
    required String mediaAssetId,
  }) async {
    final exercise = await exerciseRepository.findById(exerciseId);
    if (exercise == null) {
      throw const DomainException('Exercise not found.');
    }
    final media = await mediaRepository.findById(mediaAssetId);
    if (media == null) {
      throw const DomainException('Media asset not found.');
    }
    final updated = switch (media.kind) {
      MediaKind.image => exercise.copyWith(
        imageMediaId: media.metadata.id,
        metadata: exercise.metadata.touch(clock.now()),
      ),
      MediaKind.video => exercise.copyWith(
        videoMediaId: media.metadata.id,
        metadata: exercise.metadata.touch(clock.now()),
      ),
    };
    await exerciseRepository.save(updated);
    return updated;
  }

  Future<int> deleteOrphanedManagedFiles() async {
    final activeAssets = await mediaRepository.listActive();
    final referencedUris = activeAssets.map((asset) => asset.localUri).toSet();
    final managedUris = await storage.listManagedLocalUris();
    final orphanedUris = managedUris.difference(referencedUris);
    for (final uri in orphanedUris) {
      await storage.deleteByLocalUri(uri);
    }
    return orphanedUris.length;
  }
}

final class ProgramUseCases {
  const ProgramUseCases({
    required this.programRepository,
    required this.exerciseRepository,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final ProgramRepository programRepository;
  final ExerciseRepository exerciseRepository;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<Program?> findById(String id) => programRepository.findById(id);

  Future<List<Program>> listActive() => programRepository.listActive();

  Future<Program> create({
    required String name,
    required int defaultRestSeconds,
  }) async {
    final now = clock.now();
    final program = Program(
      metadata: _newMetadata(ids, originDeviceId, now),
      name: name,
      defaultRestSeconds: defaultRestSeconds,
    );
    await programRepository.save(program);
    return program;
  }

  Future<Program> saveConfigured({
    String? id,
    required String name,
    required int defaultRestSeconds,
    required List<ProgramExerciseConfig> exercises,
  }) async {
    final now = clock.now();
    final existing = id == null ? null : await programRepository.findById(id);
    if (id != null && existing == null) {
      throw const DomainException('Program not found.');
    }
    final programId = id ?? ids.newId();
    final metadata =
        existing?.metadata.touch(now) ??
        EntityMetadata(
          id: programId,
          createdAt: now,
          updatedAt: now,
          originDeviceId: originDeviceId,
        );
    final programExercises = <ProgramExercise>[];
    for (var index = 0; index < exercises.length; index++) {
      final input = exercises[index];
      final exerciseMetadata =
          input.existingMetadata?.touch(now) ??
          _newMetadata(ids, originDeviceId, now);
      programExercises.add(
        ProgramExercise(
          metadata: exerciseMetadata,
          programId: programId,
          sourceExerciseId: input.sourceExerciseId,
          position: index,
          exerciseNameSnapshot: input.exerciseNameSnapshot,
          exerciseDescriptionSnapshot: input.exerciseDescriptionSnapshot,
          exerciseImageMediaIdSnapshot: input.exerciseImageMediaIdSnapshot,
          exerciseVideoMediaIdSnapshot: input.exerciseVideoMediaIdSnapshot,
          exerciseArchivedSnapshot: input.exerciseArchivedSnapshot,
          availableTimeSnapshot: input.availableTimeSnapshot,
          availableRepsSnapshot: input.availableRepsSnapshot,
          availableScoreSnapshot: input.availableScoreSnapshot,
          scoreLabelSnapshot: input.scoreLabelSnapshot,
          scoreUnitSnapshot: input.scoreUnitSnapshot,
          setsCount: input.setsCount,
          timeEnabled: input.enabledMeasures.contains(WorkoutMeasure.time),
          repsEnabled: input.enabledMeasures.contains(WorkoutMeasure.reps),
          scoreEnabled: input.enabledMeasures.contains(WorkoutMeasure.score),
          targetTimeSeconds: input.targetTimeSeconds,
          targetReps: input.targetReps,
          targetScore: input.targetScore,
          restSecondsOverride: input.restSecondsOverride,
        ),
      );
    }
    final program = Program(
      metadata: metadata,
      name: name,
      defaultRestSeconds: defaultRestSeconds,
      exercises: programExercises,
    );
    await programRepository.replaceExercises(program, now);
    return program;
  }

  Future<ProgramExercise> addExercise({
    required String programId,
    required String exerciseId,
    required int position,
    required int setsCount,
    required Set<WorkoutMeasure> enabledMeasures,
    int? targetTimeSeconds,
    int? targetReps,
    double? targetScore,
    int? restSecondsOverride,
  }) async {
    final source = await exerciseRepository.findById(exerciseId);
    if (source == null) {
      throw const DomainException('Exercise not found.');
    }
    final now = clock.now();
    final programExercise = ProgramExercise.snapshotFromExercise(
      metadata: _newMetadata(ids, originDeviceId, now),
      programId: programId,
      exercise: source,
      position: position,
      setsCount: setsCount,
      enabledMeasures: enabledMeasures,
      targetTimeSeconds: targetTimeSeconds,
      targetReps: targetReps,
      targetScore: targetScore,
      restSecondsOverride: restSecondsOverride,
    );
    await programRepository.saveExercise(programExercise);
    return programExercise;
  }
}

final class ProgramExerciseConfig {
  const ProgramExerciseConfig({
    this.existingMetadata,
    this.sourceExerciseId,
    required this.exerciseNameSnapshot,
    this.exerciseDescriptionSnapshot,
    this.exerciseImageMediaIdSnapshot,
    this.exerciseVideoMediaIdSnapshot,
    this.exerciseArchivedSnapshot = false,
    required this.availableTimeSnapshot,
    required this.availableRepsSnapshot,
    required this.availableScoreSnapshot,
    this.scoreLabelSnapshot,
    this.scoreUnitSnapshot,
    required this.setsCount,
    required this.enabledMeasures,
    this.targetTimeSeconds,
    this.targetReps,
    this.targetScore,
    this.restSecondsOverride,
  });

  final EntityMetadata? existingMetadata;
  final String? sourceExerciseId;
  final String exerciseNameSnapshot;
  final String? exerciseDescriptionSnapshot;
  final String? exerciseImageMediaIdSnapshot;
  final String? exerciseVideoMediaIdSnapshot;
  final bool exerciseArchivedSnapshot;
  final bool availableTimeSnapshot;
  final bool availableRepsSnapshot;
  final bool availableScoreSnapshot;
  final String? scoreLabelSnapshot;
  final String? scoreUnitSnapshot;
  final int setsCount;
  final Set<WorkoutMeasure> enabledMeasures;
  final int? targetTimeSeconds;
  final int? targetReps;
  final double? targetScore;
  final int? restSecondsOverride;
}

final class WorkoutTemplateUseCases {
  const WorkoutTemplateUseCases({
    required this.templateRepository,
    required this.programRepository,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final WorkoutTemplateRepository templateRepository;
  final ProgramRepository programRepository;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<WorkoutTemplate?> findById(String id) {
    return templateRepository.findById(id);
  }

  Future<List<WorkoutTemplate>> listActive() {
    return templateRepository.listActive();
  }

  Future<WorkoutTemplate> create({required String name}) async {
    final now = clock.now();
    final template = WorkoutTemplate(
      metadata: _newMetadata(ids, originDeviceId, now),
      name: name,
    );
    await templateRepository.save(template);
    return template;
  }

  Future<WorkoutTemplate> saveConfigured({
    String? id,
    required String name,
    required List<WorkoutTemplateProgramConfig> programs,
    required List<WorkoutTemplateExerciseOverrideConfig> overrides,
  }) async {
    final now = clock.now();
    final existing = id == null ? null : await templateRepository.findById(id);
    if (id != null && existing == null) {
      throw const DomainException('Workout template not found.');
    }
    final templateId = id ?? ids.newId();
    final metadata =
        existing?.metadata.touch(now) ??
        EntityMetadata(
          id: templateId,
          createdAt: now,
          updatedAt: now,
          originDeviceId: originDeviceId,
        );
    final templatePrograms = <WorkoutTemplateProgram>[];
    final programIdsByClientKey = <String, String>{};
    for (var index = 0; index < programs.length; index++) {
      final input = programs[index];
      final programMetadata =
          input.existingMetadata?.touch(now) ??
          _newMetadata(ids, originDeviceId, now);
      programIdsByClientKey[input.clientKey] = programMetadata.id;
      templatePrograms.add(
        WorkoutTemplateProgram(
          metadata: programMetadata,
          workoutTemplateId: templateId,
          sourceProgramId: input.sourceProgramId,
          position: index,
          programNameSnapshot: input.programNameSnapshot,
          defaultRestSecondsSnapshot: input.defaultRestSecondsSnapshot,
          programSnapshotJson: input.programSnapshotJson,
        ),
      );
    }
    final templateOverrides = <WorkoutTemplateExerciseOverride>[];
    for (final input in overrides) {
      final workoutTemplateProgramId =
          programIdsByClientKey[input.workoutTemplateProgramClientKey];
      if (workoutTemplateProgramId == null) {
        throw const DomainException('Workout template program not found.');
      }
      templateOverrides.add(
        WorkoutTemplateExerciseOverride(
          metadata:
              input.existingMetadata?.touch(now) ??
              _newMetadata(ids, originDeviceId, now),
          workoutTemplateProgramId: workoutTemplateProgramId,
          snapshotProgramExerciseId: input.snapshotProgramExerciseId,
          setsCountOverride: input.setsCountOverride,
          targetTimeSecondsOverride: input.targetTimeSecondsOverride,
          targetRepsOverride: input.targetRepsOverride,
          targetScoreOverride: input.targetScoreOverride,
        ),
      );
    }
    final template = WorkoutTemplate(
      metadata: metadata,
      name: name,
      lastStartedAt: existing?.lastStartedAt,
      programs: templatePrograms,
      overrides: templateOverrides,
    );
    await templateRepository.replaceComposition(template, now);
    return template;
  }

  Future<WorkoutTemplateProgram> addProgramSnapshot({
    required String workoutTemplateId,
    required String programId,
    required int position,
  }) async {
    final program = await programRepository.findById(programId);
    if (program == null) {
      throw const DomainException('Program not found.');
    }
    final now = clock.now();
    final snapshot = WorkoutTemplateProgram.snapshotFromProgram(
      metadata: _newMetadata(ids, originDeviceId, now),
      workoutTemplateId: workoutTemplateId,
      program: program,
      position: position,
    );
    await templateRepository.saveProgram(snapshot);
    return snapshot;
  }

  Future<WorkoutTemplateExerciseOverride> overrideExerciseTargets({
    required String workoutTemplateProgramId,
    required String snapshotProgramExerciseId,
    int? setsCountOverride,
    int? targetTimeSecondsOverride,
    int? targetRepsOverride,
    double? targetScoreOverride,
    Set<WorkoutMeasure>? attemptedMeasureOverride,
  }) async {
    if (attemptedMeasureOverride != null) {
      throw const DomainException(
        'Workout templates cannot override active measures.',
      );
    }
    final now = clock.now();
    final override = WorkoutTemplateExerciseOverride(
      metadata: _newMetadata(ids, originDeviceId, now),
      workoutTemplateProgramId: workoutTemplateProgramId,
      snapshotProgramExerciseId: snapshotProgramExerciseId,
      setsCountOverride: setsCountOverride,
      targetTimeSecondsOverride: targetTimeSecondsOverride,
      targetRepsOverride: targetRepsOverride,
      targetScoreOverride: targetScoreOverride,
    );
    await templateRepository.saveOverride(override);
    return override;
  }
}

final class WorkoutTemplateProgramConfig {
  const WorkoutTemplateProgramConfig({
    required this.clientKey,
    this.existingMetadata,
    this.sourceProgramId,
    required this.programNameSnapshot,
    required this.defaultRestSecondsSnapshot,
    required this.programSnapshotJson,
  });

  final String clientKey;
  final EntityMetadata? existingMetadata;
  final String? sourceProgramId;
  final String programNameSnapshot;
  final int defaultRestSecondsSnapshot;
  final String programSnapshotJson;
}

final class WorkoutTemplateExerciseOverrideConfig {
  const WorkoutTemplateExerciseOverrideConfig({
    this.existingMetadata,
    required this.workoutTemplateProgramClientKey,
    required this.snapshotProgramExerciseId,
    this.setsCountOverride,
    this.targetTimeSecondsOverride,
    this.targetRepsOverride,
    this.targetScoreOverride,
  });

  final EntityMetadata? existingMetadata;
  final String workoutTemplateProgramClientKey;
  final String snapshotProgramExerciseId;
  final int? setsCountOverride;
  final int? targetTimeSecondsOverride;
  final int? targetRepsOverride;
  final double? targetScoreOverride;
}

final class ActiveWorkoutSessionUseCases {
  const ActiveWorkoutSessionUseCases({
    required this.sessionRepository,
    required this.templateRepository,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final ActiveSessionRepository sessionRepository;
  final WorkoutTemplateRepository templateRepository;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<ActiveWorkoutSession?> findOpen() => sessionRepository.findOpen();

  Future<ActiveWorkoutSession> startFromTemplate(String templateId) async {
    final template = await templateRepository.findById(templateId);
    if (template == null) {
      throw const DomainException('Workout template not found.');
    }
    final now = clock.now();
    final session = ActiveWorkoutSession(
      metadata: _newMetadata(ids, originDeviceId, now),
      sourceWorkoutTemplateId: templateId,
      status: ActiveWorkoutStatus.running,
      startedAt: now,
      lastPersistedAt: now,
      elapsedActiveMs: 0,
      currentProgramIndex: 0,
      currentExerciseIndex: 0,
      currentSetIndex: 0,
      resolvedTemplateSnapshotJson: jsonEncode({
        'templateId': template.metadata.id,
        'name': template.name,
        'programs': template.programs
            .map(
              (program) => {
                'id': program.metadata.id,
                'programNameSnapshot': program.programNameSnapshot,
                'programSnapshotJson': program.programSnapshotJson,
              },
            )
            .toList(),
        'overrides': template.overrides
            .map(
              (override) => {
                'workoutTemplateProgramId': override.workoutTemplateProgramId,
                'snapshotProgramExerciseId': override.snapshotProgramExerciseId,
                'setsCountOverride': override.setsCountOverride,
                'targetTimeSecondsOverride': override.targetTimeSecondsOverride,
                'targetRepsOverride': override.targetRepsOverride,
                'targetScoreOverride': override.targetScoreOverride,
              },
            )
            .toList(),
      }),
    );
    await sessionRepository.save(session);
    return session;
  }

  Future<ActiveWorkoutSession> startFromHistory(WorkoutHistory history) async {
    final snapshot =
        jsonDecode(history.historySnapshotJson) as Map<String, dynamic>;
    final resolvedTemplateSnapshotJson =
        snapshot['resolvedTemplateSnapshotJson'] as String;
    final now = clock.now();
    final session = ActiveWorkoutSession(
      metadata: _newMetadata(ids, originDeviceId, now),
      sourceWorkoutTemplateId: null,
      status: ActiveWorkoutStatus.running,
      startedAt: now,
      lastPersistedAt: now,
      elapsedActiveMs: 0,
      currentProgramIndex: 0,
      currentExerciseIndex: 0,
      currentSetIndex: 0,
      resolvedTemplateSnapshotJson: resolvedTemplateSnapshotJson,
    );
    await sessionRepository.save(session);
    return session;
  }

  Future<ActiveWorkoutSession> pause(String sessionId) async {
    final session = await _requiredSession(sessionId);
    final paused = session.pause(clock.now());
    await sessionRepository.save(paused);
    return paused;
  }

  Future<ActiveWorkoutSession> resume(String sessionId) async {
    final session = await _requiredSession(sessionId);
    final resumed = session.resume(clock.now());
    await sessionRepository.save(resumed);
    return resumed;
  }

  int elapsedActiveMilliseconds(ActiveWorkoutSession session) {
    return session.elapsedActiveMillisecondsAt(clock.now());
  }

  Future<ActiveSetResult> recordSetResult(ActiveSetResult result) async {
    await sessionRepository.saveSetResult(result);
    return result;
  }

  Future<ActiveSetResult> recordCurrentSetResult({
    required String sessionId,
    required String programSnapshotId,
    required String exerciseSnapshotId,
    required int programIndex,
    required int exerciseIndex,
    required int setIndex,
    int? actualTimeMs,
    int? actualReps,
    double? actualScore,
    String? scoreLabelSnapshot,
    String? scoreUnitSnapshot,
  }) async {
    final now = clock.now();
    final result = ActiveSetResult(
      metadata: _newMetadata(ids, originDeviceId, now),
      activeWorkoutSessionId: sessionId,
      programSnapshotId: programSnapshotId,
      exerciseSnapshotId: exerciseSnapshotId,
      programIndex: programIndex,
      exerciseIndex: exerciseIndex,
      setIndex: setIndex,
      completedAt: now,
      actualTimeMs: actualTimeMs,
      actualReps: actualReps,
      actualScore: actualScore,
      scoreLabelSnapshot: scoreLabelSnapshot,
      scoreUnitSnapshot: scoreUnitSnapshot,
    );
    await sessionRepository.saveSetResult(result);
    return result;
  }

  Future<ActiveWorkoutSession> updateProgress({
    required String sessionId,
    required int programIndex,
    required int exerciseIndex,
    required int setIndex,
  }) async {
    final session = await _requiredSession(sessionId);
    final updated = session.copyWith(
      currentProgramIndex: programIndex,
      currentExerciseIndex: exerciseIndex,
      currentSetIndex: setIndex,
      metadata: session.metadata.touch(clock.now()),
    );
    await sessionRepository.save(updated);
    return updated;
  }

  Future<ActiveWorkoutSession> quitAndSave(String sessionId) async {
    final session = await _requiredSession(sessionId);
    final now = clock.now();
    final saved = session.copyWith(
      status: ActiveWorkoutStatus.savedExit,
      lastPersistedAt: now,
      elapsedActiveMs: session.elapsedActiveMillisecondsAt(now),
      metadata: session.metadata.touch(now),
    );
    await sessionRepository.save(saved);
    return saved;
  }

  Future<ActiveWorkoutSession> abandon(String sessionId) async {
    final session = await _requiredSession(sessionId);
    final now = clock.now();
    final abandoned = session.copyWith(
      status: ActiveWorkoutStatus.abandoned,
      endedAt: now,
      lastPersistedAt: now,
      elapsedActiveMs: session.elapsedActiveMillisecondsAt(now),
      metadata: session.metadata.touch(now),
    );
    await sessionRepository.save(abandoned);
    return abandoned;
  }

  Future<ActiveWorkoutSession> complete(String sessionId) async {
    final session = await _requiredSession(sessionId);
    final now = clock.now();
    final completed = session.copyWith(
      status: ActiveWorkoutStatus.completed,
      endedAt: now,
      lastPersistedAt: now,
      elapsedActiveMs: session.elapsedActiveMillisecondsAt(now),
      metadata: session.metadata.touch(now),
    );
    await sessionRepository.save(completed);
    return completed;
  }

  Future<ActiveRestState> startRestAfterSet({
    required String sessionId,
    required int afterProgramIndex,
    required int afterExerciseIndex,
    required int afterSetIndex,
    required int plannedRestSeconds,
    int? adjustedRestSeconds,
  }) async {
    final now = clock.now();
    final rest = ActiveRestState(
      metadata: _newMetadata(ids, originDeviceId, now),
      activeWorkoutSessionId: sessionId,
      afterProgramIndex: afterProgramIndex,
      afterExerciseIndex: afterExerciseIndex,
      afterSetIndex: afterSetIndex,
      plannedRestSeconds: plannedRestSeconds,
      adjustedRestSeconds: adjustedRestSeconds ?? plannedRestSeconds,
      startedAt: now,
    );
    await sessionRepository.saveRestState(rest);
    return rest;
  }

  Future<ActiveWorkoutSession> _requiredSession(String sessionId) async {
    final session = await sessionRepository.findById(sessionId);
    if (session == null) {
      throw const DomainException('Active workout session not found.');
    }
    return session;
  }
}

final class CloseWorkoutSessionUseCase {
  const CloseWorkoutSessionUseCase({
    required this.sessionRepository,
    required this.historyRepository,
    required this.clock,
    required this.ids,
    required this.originDeviceId,
  });

  final ActiveSessionRepository sessionRepository;
  final WorkoutHistoryRepository historyRepository;
  final Clock clock;
  final IdGenerator ids;
  final String originDeviceId;

  Future<WorkoutHistory> close({
    required String sessionId,
    required String nameSnapshot,
    required bool completed,
  }) async {
    final session = await sessionRepository.findById(sessionId);
    if (session == null) {
      throw const DomainException('Active workout session not found.');
    }
    final now = clock.now();
    final results = await sessionRepository.listSetResults(sessionId);
    final historyId = ids.newId();
    final history = WorkoutHistory(
      metadata: EntityMetadata(
        id: historyId,
        createdAt: now,
        updatedAt: now,
        originDeviceId: originDeviceId,
      ),
      sourceWorkoutTemplateId: session.sourceWorkoutTemplateId,
      sourceActiveWorkoutSessionId: session.metadata.id,
      nameSnapshot: nameSnapshot,
      startedAt: session.startedAt,
      endedAt: now,
      totalActiveMs: session.elapsedActiveMillisecondsAt(now),
      completed: completed,
      historySnapshotJson: jsonEncode({
        'sessionId': session.metadata.id,
        'resolvedTemplateSnapshotJson': session.resolvedTemplateSnapshotJson,
        'results': results
            .map(
              (result) => {
                'programSnapshotId': result.programSnapshotId,
                'exerciseSnapshotId': result.exerciseSnapshotId,
                'programIndex': result.programIndex,
                'exerciseIndex': result.exerciseIndex,
                'setIndex': result.setIndex,
                'actualTimeMs': result.actualTimeMs,
                'actualReps': result.actualReps,
                'actualScore': result.actualScore,
                'scoreLabelSnapshot': result.scoreLabelSnapshot,
                'scoreUnitSnapshot': result.scoreUnitSnapshot,
              },
            )
            .toList(),
      }),
    );
    await historyRepository.save(history);
    return history;
  }
}

final class WorkoutHistoryUseCases {
  const WorkoutHistoryUseCases({required this.repository, required this.clock});

  final WorkoutHistoryRepository repository;
  final Clock clock;

  Future<WorkoutHistory?> findById(String id) => repository.findById(id);

  Future<List<WorkoutHistory>> listActive() => repository.listActive();

  Future<void> delete(String id) => repository.delete(id, clock.now());
}

EntityMetadata _newMetadata(
  IdGenerator ids,
  String originDeviceId,
  DateTime now,
) {
  return EntityMetadata(
    id: ids.newId(),
    createdAt: now,
    updatedAt: now,
    originDeviceId: originDeviceId,
  );
}