/*

 * Copyright (c) 2017, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

package build.tools.depend;

import com.sun.source.util.Plugin;

import java.io.File;

import java.io.IOException;

import java.io.OutputStream;

import java.net.URI;

import java.net.URISyntaxException;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.Arrays;

import java.util.List;

import javax.tools.JavaCompiler;

import javax.tools.SimpleJavaFileObject;

import javax.tools.ToolProvider;

public class DependTest {

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

        DependTest test = new DependTest();

        test.setupClass();

        test.testMethods();

        test.testFields();

        test.testModules();

        test.testAnnotations();

    }

    public void testMethods() throws Exception {

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "    public void test() {\n" +

                       "    }\n" +

                       "}",

                       true);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "    private void test() {\n" +

                       "    }\n" +

                       "}",

                       false);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "    public void test() {\n" +

                       "    }\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "}",

                       true);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "    private void test() {\n" +

                       "    }\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "}",

                       false);

    }

    public void testFields() throws Exception {

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "    public int test;\n" +

                       "}",

                       true);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "    private int test;\n" +

                       "}",

                       false);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "    public static final int test = 0;\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "    public static final int test = 1;\n" +

                       "}",

                       true);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "    public int test;\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "}",

                       true);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "    private int test;\n" +

                       "}",

                       "package test;" +

                       "public class Test {\n" +

                       "}",

                       false);

    }

    public void testAnnotations() throws Exception {

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "@SuppressWarnings(\"any\")\n" +

                       "public class Test {\n" +

                       "}",

                       false);

        doOrdinaryTest("package test;" +

                       "public class Test {\n" +

                       "}",

                       "package test;" +

                       "@Deprecated\n" +

                       "public class Test {\n" +

                       "}",

                       true);

    }

    public void testModules() throws Exception {

        doModuleTest("module m { }",

                     "module m { requires java.compiler; }",

                     true);

        doModuleTest("module m { requires java.compiler; }",

                     "module m { requires java.compiler; }",

                     false);

        doModuleTest("module m { requires java.compiler; }",

                     "module m { requires jdk.compiler; }",

                     true);

        doModuleTest("module m { }",

                     "module m { exports test; }",

                     true);

        doModuleTest("module m { }",

                     "module m { exports test to java.base; }",

                     true);

        doModuleTest("module m { }",

                     "module m { exports test to java.compiler; }",

                     true);

        doModuleTest("module m { }",

                     "module m { uses test.Test1; }",

                     true);

        doModuleTest("module m { uses test.Test1; }",

                     "module m { uses test.Test2; }",

                     true);

        doModuleTest("module m { }",

                     "module m { provides test.Test1 with test.TestImpl1; }",

                     true);

        doModuleTest("module m { provides test.Test1 with test.TestImpl1; }",

                     "module m { provides test.Test2 with test.TestImpl1; }",

                     true);

        doModuleTest("module m { provides test.Test1 with test.TestImpl1; }",

                     "module m { provides test.Test1 with test.TestImpl2; }",

                     true);

    }

    private final JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

    private Path depend;

    private Path scratchServices;

    private Path scratchClasses;

    private Path apiHash;

    private void setupClass() throws IOException {

        depend = Paths.get(Depend.class.getProtectionDomain().getCodeSource().getLocation().getPath());

        Path scratch = Files.createTempDirectory("depend-test");

        scratchServices = scratch.resolve("services");

        Path scratchClassesServices = scratchServices.resolve("META-INF").resolve("services");

        Files.createDirectories(scratchClassesServices);

        try (OutputStream out = Files.newOutputStream(scratchClassesServices.resolve(Plugin.class.getName()))) {

            out.write(Depend.class.getName().getBytes());

        }

        scratchClasses = scratch.resolve("classes");

        Files.createDirectories(scratchClasses);

        apiHash = scratch.resolve("api");

    }

    private void doOrdinaryTest(String codeBefore, String codeAfter, boolean hashChangeExpected) throws Exception {

        List<String> options =

                Arrays.asList("-d", scratchClasses.toString(),

                              "-processorpath", depend.toString() + File.pathSeparator + scratchServices.toString(),

                              "-Xplugin:depend " + apiHash.toString());

        List<TestJavaFileObject> beforeFiles =

                Arrays.asList(new TestJavaFileObject("module-info", "module m { exports test; }"),

                              new TestJavaFileObject("test.Test", codeBefore));

        compiler.getTask(null, null, null, options, null, beforeFiles).call();

        byte[] originalHash = Files.readAllBytes(apiHash);

        List<TestJavaFileObject> afterFiles =

                Arrays.asList(new TestJavaFileObject("module-info", "module m { exports test; }"),

                              new TestJavaFileObject("test.Test", codeAfter));

        compiler.getTask(null, null, null, options, null, afterFiles).call();

        byte[] newHash = Files.readAllBytes(apiHash);

        if (Arrays.equals(originalHash, newHash) ^ !hashChangeExpected) {

            throw new AssertionError("Unexpected hash state.");

        }

    }

    private void doModuleTest(String codeBefore, String codeAfter, boolean hashChangeExpected) throws Exception {

        List<String> options =

                Arrays.asList("-d", scratchClasses.toString(),

                              "-processorpath", depend.toString() + File.pathSeparator + scratchServices.toString(),

                              "-Xplugin:depend " + apiHash.toString());

        List<TestJavaFileObject> beforeFiles =

                Arrays.asList(new TestJavaFileObject("module-info", codeBefore),

                              new TestJavaFileObject("test.Test1", "package test; public interface Test1 {}"),

                              new TestJavaFileObject("test.Test2", "package test; public interface Test2 {}"),

                              new TestJavaFileObject("test.TestImpl1", "package test; public class TestImpl1 implements Test1, Test2 {}"),

                              new TestJavaFileObject("test.TestImpl2", "package test; public class TestImpl2 implements Test1, Test2 {}"));

        compiler.getTask(null, null, null, options, null, beforeFiles).call();

        byte[] originalHash = Files.readAllBytes(apiHash);

        List<TestJavaFileObject> afterFiles =

                Arrays.asList(new TestJavaFileObject("module-info", codeAfter),

                              new TestJavaFileObject("test.Test1", "package test; public interface Test1 {}"),

                              new TestJavaFileObject("test.Test2", "package test; public interface Test2 {}"),

                              new TestJavaFileObject("test.TestImpl1", "package test; public class TestImpl1 implements Test1, Test2 {}"),

                              new TestJavaFileObject("test.TestImpl2", "package test; public class TestImpl2 implements Test1, Test2 {}"));

        compiler.getTask(null, null, null, options, null, afterFiles).call();

        byte[] newHash = Files.readAllBytes(apiHash);

        if (Arrays.equals(originalHash, newHash) ^ !hashChangeExpected) {

            throw new AssertionError("Unexpected hash state.");

        }

    }

    private static final class TestJavaFileObject extends SimpleJavaFileObject {

        private final String code;

        public TestJavaFileObject(String className, String code) throws URISyntaxException {

            super(new URI("mem:/" + className.replace('.', '/') + ".java"), Kind.SOURCE);

            this.code = code;

        }

        @Override

        public CharSequence getCharContent(boolean arg0) throws IOException {

            return code;

        }

    }

}