Minifier

[thosakwe]

public class MinifierTransformer extends FrayTransformer {
  @Override
  public FrayAsset transform(FrayAsset asset) throws FrayException {
    final String src = asset.readAsString();
    final FrayParser parser = parse(src);
    final UsageTracker usageTracker = new UsageTracker();
    final Map<ParserRuleContext, String> replace = new HashMap<>();

    for (TrackedSymbol symbol : usageTracker.visitCompilationUnit(parser.compilationUnit())) {
      final String originalName = symbol.getName();
      final String newName = getUniqueIdentifier();

      for (SymbolUsage usage : symbol.getUsages()) {
        if (usage.getSource() instanceof FrayParser.IdentifierExpressionContext) {
          // Replace ID's with smaller variants
          replace.put(usage.getSource(), newName);
        }
      }
    }

    String transformed = src;

     for (ParserRuleContext ctx : replace.keySet()) {
       transformed = replaceNode(ctx, transformed, replace.get(ctx));
     }

    return asset.changeText(transformed);
  }
}