/**

 * Back 2 Browser Bytecode Translator

 * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, version 2 of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program. Look for COPYING file in the top folder.

 * If not, see http://opensource.org/licenses/GPL-2.0.

 */

package org.apidesign.vm4brwsr;

import javax.script.ScriptContext;

import javax.script.ScriptEngine;

import javax.script.ScriptException;

import org.testng.annotations.BeforeClass;

import static org.testng.Assert.*;

import org.testng.annotations.AfterClass;

import org.testng.annotations.Test;

/** Implements loading class by class.

 *

 * @author Jaroslav Tulach <jtulach@netbeans.org>

 */

public class VMLazyTest {

    private static TestVM code;

    @BeforeClass

    public static void compileTheCode() throws Exception {

        StringBuilder sb = new StringBuilder();

        sb.append("\nvar data = {};");

        sb.append("\nfunction test(clazz, method) {");

        sb.append("\n  if (!data.bck2brwsr) data.bck2brwsr = bck2brwsr(function(name) { return loader.get(name); });");

        sb.append("\n  var c = data.bck2brwsr.loadClass(clazz);");

        sb.append("\n  return c[method]();");

        sb.append("\n}");

        sb.append("\nfunction checkKO() {");

        sb.append("\n  return ko !== null;");

        sb.append("\n}");

        ScriptEngine[] arr = { null };

        code = TestVM.compileClass(sb, arr,

            new String[]{"org/apidesign/vm4brwsr/VM", "org/apidesign/vm4brwsr/StaticMethod"}

        );

        arr[0].getContext().setAttribute("loader", new BytesLoader(), ScriptContext.ENGINE_SCOPE);

    }

    @AfterClass

    public static void releaseTheCode() {

        code = null;

    }

    @Test public void invokeStaticMethod() throws Exception {

        assertExec("Trying to get -1", "test", Double.valueOf(-1),

            StaticMethod.class.getName(), "minusOne__I"

        );

    }

    @Test public void loadDependantClass() throws Exception {

        assertExec("Expecting zero", "test", Double.valueOf(0),

            InstanceSub.class.getName(), "recallDbl__D"

        );

    }

    @Test public void loadClassWithAssociatedScript() throws Exception {

        assertExec("ko is defined", "test", true,

            Script.class.getName(), "checkNotNull__Z"

        );

        Object res = code.invokeFunction("checkKO");

        assertEquals(res, true, "KO is defined on a global level");

    }

    private static void assertExec(String msg, String methodName, Object expRes, Object... args) throws Exception {

        Object ret = null;

        try {

            ret = code.invokeFunction(methodName, args);

        } catch (ScriptException ex) {

            fail("Execution failed in\n" + code.toString(), ex);

        } catch (NoSuchMethodException ex) {

            fail("Cannot find method in\n" + code.toString(), ex);

        }

        if (ret == null && expRes == null) {

            return;

        }

        if (expRes instanceof Double && ret instanceof Number) {

            ret = ((Number)ret).doubleValue();

        }

        if (expRes.equals(ret)) {

            return;

        }

        assertEquals(ret, expRes, msg + "was: " + ret + "\n" + code.toString());

    }

}