package io.quarkus.netty.deployment;

import java.util.Arrays;
import java.util.List;
import java.util.Optional;
import java.util.Random;
import java.util.function.Supplier;

import javax.inject.Singleton;

import org.jboss.logging.Logger;
import org.jboss.logmanager.Level;

import io.netty.channel.EventLoopGroup;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.logging.InternalLoggerFactory;
import io.quarkus.arc.deployment.AdditionalBeanBuildItem;
import io.quarkus.arc.deployment.SyntheticBeanBuildItem;
import io.quarkus.deployment.annotations.BuildProducer;
import io.quarkus.deployment.annotations.BuildStep;
import io.quarkus.deployment.annotations.ExecutionTime;
import io.quarkus.deployment.annotations.Record;
import io.quarkus.deployment.builditem.SystemPropertyBuildItem;
import io.quarkus.deployment.builditem.nativeimage.NativeImageConfigBuildItem;
import io.quarkus.deployment.builditem.nativeimage.NativeImageSystemPropertyBuildItem;
import io.quarkus.deployment.builditem.nativeimage.ReflectiveClassBuildItem;
import io.quarkus.deployment.builditem.nativeimage.RuntimeInitializedClassBuildItem;
import io.quarkus.deployment.builditem.nativeimage.RuntimeReinitializedClassBuildItem;
import io.quarkus.deployment.builditem.nativeimage.UnsafeAccessedFieldBuildItem;
import io.quarkus.deployment.logging.LogCleanupFilterBuildItem;
import io.quarkus.netty.BossEventLoopGroup;
import io.quarkus.netty.MainEventLoopGroup;
import io.quarkus.netty.runtime.EmptyByteBufStub;
import io.quarkus.netty.runtime.NettyRecorder;

class NettyProcessor {

    private static final Logger log = Logger.getLogger(NettyProcessor.class);

    static {
        InternalLoggerFactory.setDefaultFactory(new JBossNettyLoggerFactory());
    }

    @BuildStep
    public NativeImageSystemPropertyBuildItem limitMem() {
        //in native mode we limit the size of the epoll array
        //if the array overflows the selector just moves the overflow to a map
        return new NativeImageSystemPropertyBuildItem("sun.nio.ch.maxUpdateArraySize", "100");
    }

    @BuildStep
    public SystemPropertyBuildItem limitArenaSize() {
        //in native mode we limit the size of the epoll array
        //if the array overflows the selector just moves the overflow to a map
        return new SystemPropertyBuildItem("io.netty.allocator.maxOrder", "1");
    }

    @BuildStep
    public SystemPropertyBuildItem setNettyMachineId() {
        // we set the io.netty.machineId system property so to prevent potential
        // slowness when generating/inferring the default machine id in io.netty.channel.DefaultChannelId
        // implementation, which iterates over the NetworkInterfaces to determine the "best" machine id

        // borrowed from io.netty.util.internal.MacAddressUtil.EUI64_MAC_ADDRESS_LENGTH
        final int EUI64_MAC_ADDRESS_LENGTH = 8;
        final byte[] machineIdBytes = new byte[EUI64_MAC_ADDRESS_LENGTH];
        new Random().nextBytes(machineIdBytes);
        final String nettyMachineId = io.netty.util.internal.MacAddressUtil.formatAddress(machineIdBytes);
        return new SystemPropertyBuildItem("io.netty.machineId", nettyMachineId);
    }

    @BuildStep
    NativeImageConfigBuildItem build(BuildProducer<ReflectiveClassBuildItem> reflectiveClass) {

        reflectiveClass.produce(new ReflectiveClassBuildItem(false, false, "io.netty.channel.socket.nio.NioSocketChannel"));
        reflectiveClass
                .produce(new ReflectiveClassBuildItem(false, false, "io.netty.channel.socket.nio.NioServerSocketChannel"));
        reflectiveClass.produce(new ReflectiveClassBuildItem(false, false, "io.netty.channel.socket.nio.NioDatagramChannel"));
        reflectiveClass.produce(new ReflectiveClassBuildItem(false, false, "java.util.LinkedHashMap"));
        reflectiveClass.produce(new ReflectiveClassBuildItem(true, true, "sun.nio.ch.SelectorImpl"));

        NativeImageConfigBuildItem.Builder builder = NativeImageConfigBuildItem.builder()
                //.addNativeImageSystemProperty("io.netty.noUnsafe", "true")
                // Use small chunks to avoid a lot of wasted space. Default is 16mb * arenas (derived from core count)
                // Since buffers are cached to threads, the malloc overhead is temporary anyway
                .addNativeImageSystemProperty("io.netty.allocator.maxOrder", "1")
                .addRuntimeInitializedClass("io.netty.handler.ssl.JdkNpnApplicationProtocolNegotiator")
                .addRuntimeInitializedClass("io.netty.handler.ssl.ConscryptAlpnSslEngine")
                .addRuntimeInitializedClass("io.netty.handler.ssl.ReferenceCountedOpenSslEngine")
                .addRuntimeInitializedClass("io.netty.handler.ssl.ReferenceCountedOpenSslContext")
                .addRuntimeInitializedClass("io.netty.handler.ssl.ReferenceCountedOpenSslClientContext")
                .addRuntimeInitializedClass("io.netty.handler.ssl.util.ThreadLocalInsecureRandom")
                .addRuntimeInitializedClass("io.netty.buffer.ByteBufUtil$HexUtil")
                .addRuntimeInitializedClass("io.netty.buffer.PooledByteBufAllocator")
                .addRuntimeInitializedClass("io.netty.buffer.ByteBufAllocator")
                .addRuntimeInitializedClass("io.netty.buffer.ByteBufUtil")
                .addNativeImageSystemProperty("io.netty.leakDetection.level", "DISABLED");

        try {
            Class.forName("io.netty.handler.codec.http.HttpObjectEncoder");
            builder
                    .addRuntimeInitializedClass("io.netty.handler.codec.http.HttpObjectEncoder")
                    .addRuntimeInitializedClass("io.netty.handler.codec.http.websocketx.extensions.compression.DeflateDecoder")
                    .addRuntimeInitializedClass("io.netty.handler.codec.http.websocketx.WebSocket00FrameEncoder");
        } catch (ClassNotFoundException e) {
            //ignore
            log.debug("Not registering Netty HTTP classes as they were not found");
        }

        try {
            Class.forName("io.netty.handler.codec.http2.Http2CodecUtil");
            builder
                    .addRuntimeInitializedClass("io.netty.handler.codec.http2.Http2CodecUtil")
                    .addRuntimeInitializedClass("io.netty.handler.codec.http2.Http2ClientUpgradeCodec")
                    .addRuntimeInitializedClass("io.netty.handler.codec.http2.DefaultHttp2FrameWriter")
                    .addRuntimeInitializedClass("io.netty.handler.codec.http2.Http2ConnectionHandler");
        } catch (ClassNotFoundException e) {
            //ignore
            log.debug("Not registering Netty HTTP2 classes as they were not found");
        }

        try {
            Class.forName("io.netty.channel.unix.UnixChannel");
            builder.addRuntimeInitializedClass("io.netty.channel.unix.Errors")
                    .addRuntimeInitializedClass("io.netty.channel.unix.FileDescriptor")
                    .addRuntimeInitializedClass("io.netty.channel.unix.IovArray")
                    .addRuntimeInitializedClass("io.netty.channel.unix.Limits");
        } catch (ClassNotFoundException e) {
            //ignore
            log.debug("Not registering Netty native unix classes as they were not found");
        }

        try {
            Class.forName("io.netty.channel.epoll.EpollMode");
            builder.addRuntimeInitializedClass("io.netty.channel.epoll.Epoll")
                    .addRuntimeInitializedClass("io.netty.channel.epoll.EpollEventArray")
                    .addRuntimeInitializedClass("io.netty.channel.epoll.EpollEventLoop")
                    .addRuntimeInitializedClass("io.netty.channel.epoll.Native");
        } catch (ClassNotFoundException e) {
            //ignore
            log.debug("Not registering Netty native epoll classes as they were not found");
        }

        try {
            Class.forName("io.netty.channel.kqueue.AcceptFilter");
            builder.addRuntimeInitializedClass("io.netty.channel.kqueue.KQueue")
                    .addRuntimeInitializedClass("io.netty.channel.kqueue.KQueueEventArray")
                    .addRuntimeInitializedClass("io.netty.channel.kqueue.KQueueEventLoop")
                    .addRuntimeInitializedClass("io.netty.channel.kqueue.Native");
        } catch (ClassNotFoundException e) {
            //ignore
            log.debug("Not registering Netty native kqueue classes as they were not found");
        }

        return builder //TODO: make configurable
                .build();
    }

    @BuildStep
    @Record(ExecutionTime.RUNTIME_INIT)
    public void eagerlyInitClass(NettyRecorder recorder) {
        //see https://github.com/quarkusio/quarkus/issues/3663
        //this class is slow to initialize, we make sure that we do it eagerly
        //before it blocks the IO thread and causes a warning
        recorder.eagerlyInitChannelId();
    }

    @SuppressWarnings({ "unchecked", "rawtypes" })
    @BuildStep
    @Record(ExecutionTime.RUNTIME_INIT)
    void registerEventLoopBeans(BuildProducer<SyntheticBeanBuildItem> syntheticBeans,
            Optional<EventLoopSupplierBuildItem> loopSupplierBuildItem,
            NettyRecorder recorder) {
        Supplier<Object> boss;
        Supplier<Object> main;
        if (loopSupplierBuildItem.isPresent()) {
            boss = (Supplier) loopSupplierBuildItem.get().getBossSupplier();
            main = (Supplier) loopSupplierBuildItem.get().getMainSupplier();
        } else {
            boss = recorder.createEventLoop(1);
            main = recorder.createEventLoop(0);
        }

        // IMPLEMENTATION NOTE:
        // We use Singleton scope for both beans. ApplicationScoped causes problems with EventLoopGroup.next() 
        // which overrides the EventExecutorGroup.next() method but since Netty 4 is compiled with JDK6 the corresponding bridge method 
        // is not generated and the invocation upon the client proxy results in an AbstractMethodError 
        syntheticBeans.produce(SyntheticBeanBuildItem.configure(EventLoopGroup.class)
                .supplier(boss)
                .scope(Singleton.class)
                .addQualifier(BossEventLoopGroup.class)
                .unremovable()
                .setRuntimeInit()
                .done());
        syntheticBeans.produce(SyntheticBeanBuildItem.configure(EventLoopGroup.class)
                .supplier(main)
                .scope(Singleton.class)
                .addQualifier(MainEventLoopGroup.class)
                .unremovable()
                .setRuntimeInit()
                .done());
    }

    @BuildStep
    AdditionalBeanBuildItem registerQualifiers() {
        // We need to register the qualifiers manually because they're not part of the index
        // Previously they were indexed because we indexed the "uber-producer-class" generated for RuntimeBeanBuildItems
        return AdditionalBeanBuildItem.builder().addBeanClasses(BossEventLoopGroup.class, MainEventLoopGroup.class).build();
    }

    @BuildStep
    public RuntimeReinitializedClassBuildItem reinitScheduledFutureTask() {
        return new RuntimeReinitializedClassBuildItem(
                "io.quarkus.netty.runtime.graal.Holder_io_netty_util_concurrent_ScheduledFutureTask");
    }

    @BuildStep
    public List<UnsafeAccessedFieldBuildItem> unsafeAccessedFields() {
        return Arrays.asList(
                new UnsafeAccessedFieldBuildItem("sun.nio.ch.SelectorImpl", "selectedKeys"),
                new UnsafeAccessedFieldBuildItem("sun.nio.ch.SelectorImpl", "publicSelectedKeys"),

                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.MpscArrayQueueProducerIndexField", "producerIndex"),
                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.MpscArrayQueueProducerLimitField", "producerLimit"),
                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.MpscArrayQueueConsumerIndexField", "consumerIndex"),

                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.BaseMpscLinkedArrayQueueProducerFields",
                        "producerIndex"),
                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.BaseMpscLinkedArrayQueueColdProducerFields",
                        "producerLimit"),
                new UnsafeAccessedFieldBuildItem(
                        "io.netty.util.internal.shaded.org.jctools.queues.BaseMpscLinkedArrayQueueConsumerFields",
                        "consumerIndex"));
    }

    @BuildStep
    RuntimeInitializedClassBuildItem runtimeInitBcryptUtil() {
        // this holds a direct allocated byte buffer that needs to be initialised at run time
        return new RuntimeInitializedClassBuildItem(EmptyByteBufStub.class.getName());
    }

    //if debug logging is enabled netty logs lots of exceptions
    //see https://github.com/quarkusio/quarkus/issues/5213
    @BuildStep
    LogCleanupFilterBuildItem cleanup() {
        return new LogCleanupFilterBuildItem(PlatformDependent.class.getName() + "0", Level.TRACE, "direct buffer constructor",
                "jdk.internal.misc.Unsafe", "sun.misc.Unsafe");
    }
}
