scan method

@override Future<ScannerResult> scan(ProjectContext context)

Executes the scan and returns a ScannerResult.

Implementation

@override
Future<ScannerResult> scan(ProjectContext context) async {
  context.logger.startSpinner('Scanning Assets...');

  final issues = <Issue>[];
  int totalAssets = 0;
  double totalSizeMb = 0.0;

  final flutterMap = context.pubspec?['flutter'] as Map?;
  final assetsList = flutterMap?['assets'];
  if (assetsList == null || assetsList is! List) {
    context.logger.stopSpinner();
    return ScannerResult(issues: issues, metrics: {});
  }

  final declaredAssets = <String>{};
  for (final asset in assetsList) {
    declaredAssets.add(asset.toString());
  }

  // Expand directories to actual files
  final actualAssetFiles = <File>[];
  for (final assetPath in declaredAssets) {
    if (assetPath.endsWith('/')) {
      final dir = Directory(p.join(context.directory, assetPath));
      if (dir.existsSync()) {
        actualAssetFiles.addAll(
          dir.listSync(recursive: false).whereType<File>(),
        );
      }
    } else {
      final file = File(p.join(context.directory, assetPath));
      if (file.existsSync()) {
        actualAssetFiles.add(file);
      } else {
        issues.add(
          Issue(
            title: 'Missing Asset',
            description:
                'Asset "$assetPath" is declared in pubspec.yaml but does not exist.',
            category: 'Assets',
            severity: IssueSeverity.high,
            suggestion:
                'Remove it from pubspec.yaml or add the missing file.',
          ),
        );
      }
    }
  }

  // Find all strings in dart code (simple regex for now, AST is more complex for pure string finding across whole codebase quickly, but let's do a fast regex + AST combined approach)
  final dartFiles = FileUtils.getDartFiles(context.directory);
  final allDartCode = dartFiles.map((f) => f.readAsStringSync()).join('\n');

  final assetHashes = <String, String>{}; // hash -> path

  for (final file in actualAssetFiles) {
    totalAssets++;
    final fileSize = file.lengthSync() / (1024 * 1024);
    totalSizeMb += fileSize;

    final relPath = p.relative(file.path, from: context.directory);

    // Check if it's used in code
    // We look for Exact String references, Image.asset(), etc.
    // Easiest robust way for asset usages is checking if the exact relative path string exists anywhere in Dart code.
    if (!allDartCode.contains(relPath) &&
        !allDartCode.contains(p.basename(relPath))) {
      issues.add(
        Issue(
          title: 'Unused Asset',
          description: 'Asset "$relPath" is not referenced in any Dart file.',
          category: 'Assets',
          severity: IssueSeverity.medium,
          file: relPath,
          suggestion: 'Delete the asset to save space.',
        ),
      );
    }

    // Check duplicates
    final bytes = file.readAsBytesSync();
    final hash = md5.convert(bytes).toString();

    if (assetHashes.containsKey(hash)) {
      issues.add(
        Issue(
          title: 'Duplicate Asset',
          description:
              'Asset "$relPath" is identical to "${assetHashes[hash]}".',
          category: 'Assets',
          severity: IssueSeverity.medium,
          file: relPath,
          suggestion:
              'Use a single asset reference and delete the duplicate.',
        ),
      );
    } else {
      assetHashes[hash] = relPath;
    }

    // Check sizes
    if (fileSize > context.config.maxImageSizeMb) {
      issues.add(
        Issue(
          title: 'Oversized Asset',
          description:
              'Asset "$relPath" is ${fileSize.toStringAsFixed(2)}MB (Limit: ${context.config.maxImageSizeMb}MB).',
          category: 'Assets',
          severity: IssueSeverity.high,
          file: relPath,
          suggestion: 'Compress the asset or use a vector format (SVG).',
        ),
      );
    }
  }

  context.logger.stopSpinner();
  return ScannerResult(
    issues: issues,
    metrics: {
      'total_assets': totalAssets,
      'total_assets_size_mb': totalSizeMb,
    },
  );
}