calculateMetrics method

Map<String, dynamic> calculateMetrics({ required List<ProviderNode> nodes, required int filesProcessed, List<ArchitectureSmell> smells = const [], List<GovernanceViolation> violations = const [], int partialMigrations = 0, })

Calculates migration and health metrics from nodes, smells, and violations.

partialMigrations is the count of files that received TODO placeholders or UnimplementedError stubs — used to compute an honest success ratio.

Returns a map with keys: logic_units_migrated, methods_transformed, files_processed, estimated_hours_saved, boilerplate_reduction_percent, architecture_health_score, smells_count, violations_count, and migration_success_ratio.

Implementation

Map<String, dynamic> calculateMetrics({
  required List<ProviderNode> nodes,
  required int filesProcessed,
  List<ArchitectureSmell> smells = const [],
  List<GovernanceViolation> violations = const [],
  int partialMigrations = 0,
}) {
  final logicUnits = nodes.whereType<LogicUnitNode>().length;
  final totalMethods = nodes.whereType<LogicUnitNode>().fold(
    0,
    (sum, node) => sum + node.methods.length,
  );

  // Estimation: 2h per logic unit, 30m per method.
  final estimatedHoursSaved = (logicUnits * 2) + (totalMethods * 0.5);

  // Architecture Health Score — severity-weighted deductions.
  // error smells (e.g. circular dependency) deduct more than info smells.
  double healthScore = 100.0;
  for (final smell in smells) {
    healthScore -= switch (smell.severity) {
      'error' => 10.0,
      'warning' => 2.5,
      _ => 1.0,
    };
  }
  for (final violation in violations) {
    healthScore -= switch (violation.severity) {
      'error' => 8.0,
      _ => 3.0,
    };
  }
  if (healthScore < 0) healthScore = 0.0;

  // Honest migration success ratio — partial migrations count against it.
  final successRatio = filesProcessed > 0
      ? ((filesProcessed - partialMigrations) / filesProcessed)
          .clamp(0.0, 1.0)
      : 1.0;

  return {
    'logic_units_migrated': logicUnits,
    'methods_transformed': totalMethods,
    'files_processed': filesProcessed,
    'estimated_hours_saved': estimatedHoursSaved,
    'boilerplate_reduction_percent':
        (successRatio * 0.15 * 100).toStringAsFixed(1),
    'architecture_health_score': healthScore.toStringAsFixed(1),
    'smells_count': smells.length,
    'violations_count': violations.length,
    'migration_success_ratio': double.parse(successRatio.toStringAsFixed(2)),
  };
}