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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.truffle.api.test.polyglot;

import com.oracle.truffle.api.CallTarget;
import com.oracle.truffle.api.Truffle;
import com.oracle.truffle.api.TruffleLanguage.Env;
import com.oracle.truffle.api.nodes.RootNode;
import com.oracle.truffle.api.source.Source;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicReference;
import org.graalvm.polyglot.Context;
import static org.junit.Assert.assertTrue;
import org.junit.Test;

public class MultiThreadedCloseTest extends AbstractPolyglotTest {

    public MultiThreadedCloseTest() {
        enterContext = false;
    }

    @Test
    public void testWithExecutor() {
        setupEnv(Context.newBuilder().allowCreateThread(true).build(), new CloseLanguage() {

            @Override
            protected void initializeContext(CloseContext ctx) throws Exception {
                ctx.executor = Executors.newCachedThreadPool((r) -> {
                    return ctx.registerThread(ctx.env.createThread(r, null, ctx.group));
                });
                ctx.executor.submit(() -> {
                    ctx.env.parseInternal(Source.newBuilder(ProxyLanguage.ID, "", "test").build());
                });
            }

            @Override
            protected void finalizeContext(CloseContext ctx) {
                ctx.executor.shutdownNow();
                assertTrue(ctx.executor.isShutdown());
                try {
                    ctx.joinThreads();
                } catch (InterruptedException ie) {
                    throw new RuntimeException(ie);
                }
            }
        });
        context.eval(ProxyLanguage.ID, "");
    }

    @Test
    public void testWithThreads() {
        setupEnv(Context.newBuilder().allowCreateThread(true).build(), new CloseLanguage() {

            @Override
            protected void initializeContext(CloseContext ctx) throws Exception {
                ctx.registerThread(ctx.env.createThread(() -> {
                    ctx.env.parseInternal(Source.newBuilder(ProxyLanguage.ID, "", "test").build());
                }, null, ctx.group)).start();
            }

            @Override
            protected void finalizeContext(CloseContext ctx) {
                try {
                    ctx.joinThreads();
                } catch (InterruptedException ie) {
                    throw new RuntimeException(ie);
                }
            }
        });
        context.eval(ProxyLanguage.ID, "");
    }

    private static class CloseContext extends ProxyLanguage.LanguageContext {

        final AtomicReference<Collection<Thread>> createdThreads;
        final ThreadGroup group;
        ExecutorService executor;

        CloseContext(Env env) {
            super(env);
            this.createdThreads = new AtomicReference<>(Collections.synchronizedList(new ArrayList<>()));
            this.group = new ThreadGroup(getClass().getSimpleName());
        }

        Thread registerThread(Thread thread) {
            Collection<Thread> into = createdThreads.get();
            if (into == null) {
                throw new IllegalStateException("Creating a Thread after finalizeContext");
            }
            into.add(thread);
            return thread;
        }

        void joinThreads() throws InterruptedException {
            Collection<Thread> toJoin = createdThreads.getAndSet(null);
            if (toJoin == null) {
                return;
            }
            for (Thread t : toJoin) {
                t.join();
            }
        }
    }

    private abstract static class CloseLanguage extends ProxyLanguage {

        @Override
        protected final boolean isThreadAccessAllowed(Thread thread, boolean singleThreaded) {
            return true;
        }

        @Override
        protected LanguageContext createContext(Env env) {
            super.createContext(env);
            return new CloseContext(env);
        }

        @Override
        protected final void initializeContext(LanguageContext context) throws Exception {
            initializeContext((CloseContext) context);
        }

        protected abstract void initializeContext(CloseContext context) throws Exception;

        @Override
        protected void finalizeContext(LanguageContext context) {
            finalizeContext((CloseContext) context);
        }

        protected abstract void finalizeContext(CloseContext context);

        @Override
        protected CallTarget parse(ParsingRequest request) throws Exception {
            return Truffle.getRuntime().createCallTarget(RootNode.createConstantNode(true));
        }
    }
}