package src;
import gen.PortugaLexer;
import gen.PortugaParser;
import org.antlr.v4.gui.TreeViewer;
import org.antlr.v4.runtime.ANTLRFileStream;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.tree.ParseTree;

import java.io.IOException;
import java.util.Arrays;


public class Main {

    public static void main(String args[]) throws IOException{
        String path;
        if(args.length > 0){
             path = args[0];
        }else{
            path = "input.txt";
        }
        try{
            ANTLRFileStream input = new ANTLRFileStream(path);

            PortugaLexer lexer = new PortugaLexer(input);
            CommonTokenStream tokens = new CommonTokenStream(lexer);
            PortugaParser parser = new PortugaParser(tokens);
            //Remove o tratamento padrao, pra evitar duplicacao de mensagem
            parser.removeErrorListeners();

            //Adiciona nosso Listener
            MyError errorListener = new MyError();
            parser.addErrorListener(errorListener);
            ParseTree tree = parser.program();

            //Verifica se houve algum erro, e se sim throw antes de criar o viewer.
            if(!errorListener.errors.isEmpty()){
                throw new RuntimeException(String.join("\n", errorListener.errors));
            }
            TreeViewer viewer = new TreeViewer(Arrays.asList(parser.getRuleNames()), tree);
            viewer.open();
        }catch(RuntimeException e){
            System.out.println(e.getMessage());
        }

    }
}