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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * 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,

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package org.graalvm.compiler.core.test;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.lang.reflect.Constructor;

import org.graalvm.compiler.java.GraphBuilderPhase;

import org.graalvm.compiler.nodes.DeoptimizeNode;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;

import org.graalvm.compiler.nodes.graphbuilderconf.GraphBuilderConfiguration;

import org.graalvm.compiler.nodes.java.NewInstanceNode;

import org.graalvm.compiler.options.OptionValues;

import org.graalvm.compiler.phases.OptimisticOptimizations;

import org.junit.Assert;

import org.junit.Test;

import jdk.vm.ci.meta.ResolvedJavaMethod;

public class NewInstanceTest extends GraalCompilerTest {

    public static class Template {

        public Object o = new CCCC();

    }

    /**

     * 1. Concrete class, should produce normal {@link NewInstanceNode}

     */

    public static class CCCC {

    }

    /**

     * 2. The test will replace references to {@link CCCC} in the {@link Template} to {@link AAAA}

     */

    public abstract static class AAAA {

    }

    /**

     * 3. The test will replace references to {@link CCCC} in the {@link Template} to {@link IIII}

     */

    public interface IIII {

    }

    private StructuredGraph parseAndProcess(Class<?> cl) {

        Constructor<?>[] constructors = cl.getConstructors();

        Assert.assertTrue(constructors.length == 1);

        final ResolvedJavaMethod javaMethod = getMetaAccess().lookupJavaMethod(constructors[0]);

        OptionValues options = getInitialOptions();

        StructuredGraph graph = new StructuredGraph.Builder(options, getDebugContext(options, null, javaMethod), AllowAssumptions.YES).method(javaMethod).build();

        GraphBuilderConfiguration conf = GraphBuilderConfiguration.getSnippetDefault(getDefaultGraphBuilderPlugins()).withUnresolvedIsError(false);

        new GraphBuilderPhase.Instance(getProviders(), conf, OptimisticOptimizations.ALL, null).apply(graph);

        return graph;

    }

    private void checkGraph(Class<?> cl, int newInstanceNodeCount, int deoptimizeNodeCount) {

        StructuredGraph graph = parseAndProcess(cl);

        Assert.assertEquals(newInstanceNodeCount, graph.getNodes().filter(NewInstanceNode.class).count());

        Assert.assertEquals(deoptimizeNodeCount, graph.getNodes().filter(DeoptimizeNode.class).count());

    }

    /**

     * Use a custom class loader to generate classes, substitute class names at the allocation site.

     */

    @Test

    public void test1() throws ClassNotFoundException {

        checkGraph(Template.class, 1, 0);

        ClassTemplateLoader loader1 = new ClassTemplateLoader("CCCC", "AAAA");

        checkGraph(loader1.findClass("Template"), 0, 1);

        ClassTemplateLoader loader2 = new ClassTemplateLoader("CCCC", "IIII");

        checkGraph(loader2.findClass("Template"), 0, 1);

    }

    private static class ClassTemplateLoader extends ClassLoader {

        private final String find;

        private final String replace;

        ClassTemplateLoader(String find, String replace) {

            assert find.length() == replace.length();

            this.find = find;

            this.replace = replace;

        }

        @Override

        protected Class<?> findClass(final String name) throws ClassNotFoundException {

            // copy classfile to byte array

            byte[] classData = null;

            try {

                InputStream is = NewInstanceTest.class.getResourceAsStream("NewInstanceTest$" + name + ".class");

                assert is != null;

                ByteArrayOutputStream baos = new ByteArrayOutputStream();

                byte[] buf = new byte[1024];

                int size;

                while ((size = is.read(buf, 0, buf.length)) != -1) {

                    baos.write(buf, 0, size);

                }

                baos.flush();

                classData = baos.toByteArray();

            } catch (IOException e) {

                Assert.fail("can't access class: " + name);

            }

            // replace all occurrences of the template in classfile

            int index = -1;

            while ((index = indexOfTemplate(classData, index + 1, find)) != -1) {

                replaceTemplate(classData, index, replace);

            }

            Class<?> c = defineClass(null, classData, 0, classData.length);

            return c;

        }

        private static int indexOfTemplate(byte[] b, int index, String find) {

            for (int i = index; i < b.length; i++) {

                boolean match = true;

                for (int j = i; j < i + find.length(); j++) {

                    if (b[j] != (byte) find.charAt(j - i)) {

                        match = false;

                        break;

                    }

                }

                if (match) {

                    return i;

                }

            }

            return -1;

        }

        private static void replaceTemplate(byte[] b, int index, String replace) {

            for (int i = index; i < index + replace.length(); i++) {

                b[i] = (byte) replace.charAt(i - index);

            }

        }

    }

}