/*

 * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.io.IOException;

import java.lang.reflect.Method;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.stream.Collectors;

public class Wrapper {

    public static void main(String... args) throws Exception {

        if (!isSJavacOnClassPath()) {

            System.out.println("sjavac not available: pass by default");

            return;

        }

        String testClassName = args[0];

        String[] testArgs = Arrays.copyOfRange(args, 1, args.length);

        Path srcDir = Paths.get(System.getProperty("test.src"));

        Path clsDir = Paths.get(System.getProperty("test.classes"));

        String clsPath = System.getProperty("test.class.path");

        String tstMdls = System.getProperty("test.modules");

        Path src = srcDir.resolve(testClassName + ".java");

        Path cls = clsDir.resolve(testClassName + ".class");

        if (isNewer(src, cls)) {

            System.err.println("Recompiling test class...");

            List<String> javacArgs = new ArrayList<>();

            javacArgs.addAll(Arrays.asList("-d", clsDir.toString()));

            javacArgs.addAll(Arrays.asList("-sourcepath", srcDir.toString()));

            javacArgs.addAll(Arrays.asList("-classpath", clsPath));

            Arrays.stream(tstMdls.split("\\s+"))

                .filter(s -> s.contains("/"))

                .map(s -> "--add-exports=" + s + "=ALL-UNNAMED")

                .collect(Collectors.toCollection(() -> javacArgs));

            javacArgs.add(src.toString());

            System.out.println("javac: " + javacArgs);

            int rc = com.sun.tools.javac.Main.compile(

                javacArgs.toArray(new String[javacArgs.size()]));

            if (rc != 0)

                throw new Exception("compilation failed");

        }

        Class<?> sjavac = Class.forName(testClassName);

        Method main = sjavac.getMethod("main", String[].class);

        main.invoke(null, new Object[] { testArgs });

    }

    private static boolean isNewer(Path a, Path b) throws IOException {

        if (Files.notExists(b))

            return true;

        return Files.getLastModifiedTime(a).compareTo(Files.getLastModifiedTime(b)) > 0;

    }

    private static boolean isSJavacOnClassPath() {

        String cls = "com/sun/tools/sjavac/Main.class";

        return Wrapper.class.getClassLoader().getResource(cls) != null;

    }

}