/*

Java 4 Browser Bytecode Translator

Copyright (C) 2012-2012 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 org.apidesign.vm4brwsr.ByteCodeToJavaScript;

import java.io.IOException;

import java.io.InputStream;

import java.util.Arrays;

import java.util.HashSet;

import java.util.Iterator;

import java.util.LinkedList;

import java.util.Set;

import java.util.TreeSet;

import javax.script.Invocable;

import javax.script.ScriptEngine;

import javax.script.ScriptEngineManager;

import javax.script.ScriptException;

import static org.testng.Assert.*;

import org.testng.annotations.Test;

/** Checks the basic behavior of the translator.

 *

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

 */

public class StaticMethodTest {

    @Test public void threePlusFour() throws Exception {

        assertExec(

            "Should be seven", 

            "org_apidesign_vm4brwsr_StaticMethod_sumIII", 

            Double.valueOf(7), 

            3, 4

        );

    }

    @Test public void powerOfThree() throws Exception {

        assertExec(

            "Should be nine", 

            "org_apidesign_vm4brwsr_StaticMethod_powerFF", 

            Double.valueOf(9),

            3.0f

        );

    }

    @Test public void doubleWithoutLong() throws Exception {

        assertExec(

            "Should be two",

            "org_apidesign_vm4brwsr_StaticMethod_minusDDJ", 

            Double.valueOf(2),

            3.0d, 1l

        );

    }

    @Test public void divAndRound() throws Exception {

        assertExec(

            "Should be rounded to one",

            "org_apidesign_vm4brwsr_StaticMethod_divIBD", 

            Double.valueOf(1),

            3, 3.75

        );

    }

    @Test public void mixedMethodFourParams() throws Exception {

        assertExec(

            "Should be two",

            "org_apidesign_vm4brwsr_StaticMethod_mixIIJBD", 

            Double.valueOf(20),

            2, 10l, 5, 2.0

        );

    }

    @Test public void factRec() throws Exception {

        assertExec(

            "Factorial of 5 is 120",

            "org_apidesign_vm4brwsr_StaticMethod_factRecJI", 

            Double.valueOf(120),

            5

        );

    }

    @Test public void factIter() throws Exception {

        assertExec(

            "Factorial of 5 is 120",

            "org_apidesign_vm4brwsr_StaticMethod_factIterJI", 

            Double.valueOf(120),

            5

        );

    }

    @Test public void xor() throws Exception {

        assertExec(

            "Xor is 4",

            "org_apidesign_vm4brwsr_StaticMethod_xorJIJ",

            Double.valueOf(4),

            7,

            3

        );

    }

    @Test public void or() throws Exception {

        assertExec(

            "Or will be 7",

            "org_apidesign_vm4brwsr_StaticMethod_orOrAndJZII",

            Double.valueOf(7),

            true,

            4,

            3

        );

    }

    @Test public void and() throws Exception {

        assertExec(

            "And will be 3",

            "org_apidesign_vm4brwsr_StaticMethod_orOrAndJZII",

            Double.valueOf(3),

            false,

            7,

            3

        );

    }

    @Test public void inc4() throws Exception {

        assertExec(

            "It will be 4",

            "org_apidesign_vm4brwsr_StaticMethod_inc4I",

            Double.valueOf(4)

        );

    }

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

        StringBuilder sb = new StringBuilder();

        Invocable i = compileClass(sb, "org/apidesign/vm4brwsr/StaticMethod");

        Object ret = null;

        try {

            ret = i.invokeFunction(methodName, args);

        } catch (ScriptException ex) {

            fail("Execution failed in " + sb, ex);

        } catch (NoSuchMethodException ex) {

            fail("Cannot find method in " + sb, ex);

        }

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

            return;

        }

        if (expRes.equals(ret)) {

            return;

        }

        assertEquals(ret, expRes, msg + "was: " + ret + "\n" + sb);

    }

    static Invocable compileClass(StringBuilder sb, String... names) throws ScriptException, IOException {

        if (sb == null) {

            sb = new StringBuilder();

        }

        Set<String> processed = new HashSet<String>();

        LinkedList<String> toProcess = new LinkedList<String>(Arrays.asList(names));

        for (;;) {

            toProcess.removeAll(processed);

            if (toProcess.isEmpty()) {

                break;

            }

            String name = toProcess.getFirst();

            processed.add(name);

            if (name.startsWith("java/") && !name.equals("java/lang/Object")) {

                continue;

            }

            InputStream is = StaticMethodTest.class.getClassLoader().getResourceAsStream(name + ".class");

            assertNotNull(is, "Class file found");

            try {

                ByteCodeToJavaScript.compile(is, sb, toProcess);

            } catch (RuntimeException ex) {

                int lastBlock = sb.lastIndexOf("{");

                throw new IllegalStateException(

                    "Error while compiling " + name + "\n" + 

                    sb.substring(0, sb.length()), 

                    ex

                );

            }

        }

        ScriptEngineManager sem = new ScriptEngineManager();

        ScriptEngine js = sem.getEngineByExtension("js");

        try {

            Object res = js.eval(sb.toString());

            assertTrue(js instanceof Invocable, "It is invocable object: " + res);

            return (Invocable)js;

        } catch (ScriptException ex) {

            fail("Could not compile:\n" + sb, ex);

            return null;

        }

    }

}