package acceptance.fixture;

import static table.FunctionTable.resetFunctionTable;

import java.io.*;

import interpreter.*;
import table.ExecutionContext;

public class LispInterpreterFixture {

    private static ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    private static LispInterpreter interpreter = null;

    static {
        LispInterpreterBuilder builder = LispInterpreterBuilderImpl.getInstance();
        builder.setOutput(new PrintStream(outputStream));
        builder.setErrorOutput(new PrintStream(outputStream));
        builder.setNotInteractive();
        builder.setTerminationFunction(() -> {});
        builder.setErrorTerminationFunction(() -> {});

        interpreter = builder.build();
    }

    public void reset() {
        resetFunctionTable();
        ExecutionContext.getInstance().clearContext();
    }

    public String evaluate(String input) throws IOException {
        interpreter.setInput(new ByteArrayInputStream(input.getBytes()), "fitnesse");
        interpreter.interpret();
        String output = outputStream.toString();
        outputStream.reset();

        return output.trim();
    }

}