import 'muscle_group.dart';

/// One logged resistance-training working set group: the exercise performed,
/// the muscle group it targeted, and the volume/LOAD prescription.
///
/// Pure Dart (no framework imports) so the entity can be shared by the
/// repository contract and the Riverpod presentation layer without leaking
/// infrastructure concerns into the domain.
class ExerciseEntry {
  const ExerciseEntry({
    required this.id,
    required this.timestamp,
    required this.muscleGroup,
    required this.exerciseName,
    required this.sets,
    required this.reps,
    this.weightLbs = 0,
  });

  /// UUID primary key assigned when the entry is first materialized.
  final String id;

  /// When the working set was performed.
  final DateTime timestamp;

  /// Muscle group trained (drives grouping and weekly frequency rollups).
  final MuscleGroup muscleGroup;

  /// Free-text exercise name (e.g. "Back Squat", "Lat Pulldown").
  final String exerciseName;

  /// Number of working sets performed.
  final int sets;

  /// Repetitions per set.
  final int reps;

  /// Load moved per set in pounds; `0` for bodyweight work.
  final double weightLbs;

  /// Human-readable prescription, e.g. `3 × 8 @ 135 lb` or `3 × 12`
  /// for bodyweight work.
  String get volumeLabel {
    final load = weightLbs > 0 ? ' @ ${formatWeight(weightLbs)} lb' : '';
    return '$sets × $reps$load';
  }

  /// Formats a weight: whole numbers drop the decimal (`135`), fractional
  /// loads keep one digit (`137.5`).
  static String formatWeight(double weightLbs) {
    final rounded = weightLbs.roundToDouble();
    return rounded == weightLbs
        ? rounded.toStringAsFixed(0)
        : weightLbs.toStringAsFixed(1);
  }

  @override
  String toString() =>
      'ExerciseEntry($id, ${exerciseName.trim()}, ${muscleGroup.name}, '
      '$volumeLabel @ $timestamp)';
}