/*
 * Copyright (c) 2009, 2015, 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
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 */
import java.util.HashSet;
import java.util.Set;

import javax.annotation.processing.*;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.*;
import javax.lang.model.util.ElementFilter;

import com.sun.source.util.JavacTask;
import com.sun.source.util.TaskEvent;
import com.sun.source.util.TaskListener;
import com.sun.tools.javac.main.JavaCompiler;
import com.sun.tools.javac.processing.JavacProcessingEnvironment;
import com.sun.tools.javac.util.Context;

import static com.sun.tools.javac.comp.CompileStates.CompileState;

/*
 * @test
 * @summary test that package annotations are available to type processors.
 * This class implements the functionality of a type processor, as previously
 * embodied by the AbstractTypeProcessor class.
 *
 * @author Mahmood Ali
 * @author Werner Dietl
 *
 * @modules jdk.compiler/com.sun.tools.javac.comp
 *          jdk.compiler/com.sun.tools.javac.main
 *          jdk.compiler/com.sun.tools.javac.processing
 *          jdk.compiler/com.sun.tools.javac.util
 * @compile PackageProcessor.java
 * @compile -cp . -processor PackageProcessor mypackage/Anno.java mypackage/MyClass.java mypackage/package-info.java
 */

@SupportedAnnotationTypes("*")
public class PackageProcessor extends AbstractProcessor {

    private final AttributionTaskListener listener = new AttributionTaskListener();
    private final Set<Name> elements = new HashSet<Name>();

    @Override
    public final void init(ProcessingEnvironment env) {
        super.init(env);
        JavacTask.instance(env).addTaskListener(listener);
        Context ctx = ((JavacProcessingEnvironment)processingEnv).getContext();
        JavaCompiler compiler = JavaCompiler.instance(ctx);
        compiler.shouldStopPolicyIfNoError = CompileState.max(compiler.shouldStopPolicyIfNoError,
                CompileState.FLOW);
    }

    @Override
    public final boolean process(Set<? extends TypeElement> annotations,
            RoundEnvironment roundEnv) {
        for (TypeElement elem : ElementFilter.typesIn(roundEnv.getRootElements())) {
            elements.add(elem.getQualifiedName());
        }
        return false;
    }

    @Override
    public SourceVersion getSupportedSourceVersion() {
        return SourceVersion.latest();
    }

    private final class AttributionTaskListener implements TaskListener {
        @Override
        public void started(TaskEvent e) { }

        @Override
        public void finished(TaskEvent e) {
            if (e.getKind() != TaskEvent.Kind.ANALYZE)
                return;

            if (!elements.remove(e.getTypeElement().getQualifiedName()))
                return;

            if (e.getTypeElement().getSimpleName().contentEquals("MyClass")) {
                Element owner = e.getTypeElement().getEnclosingElement();
                if (owner.getKind() != ElementKind.PACKAGE)
                    throw new RuntimeException("class owner should be a package: " + owner);
                if (owner.getAnnotationMirrors().size() != 1)
                    throw new RuntimeException("the owner package should have one annotation: " + owner);
            }
        }
    }

}