/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

{{#packageName}}
package {{packageName}};
{{/packageName}}

import org.apache.dubbo.common.stream.StreamObserver;
import org.apache.dubbo.common.URL;
import org.apache.dubbo.rpc.Invoker;
import org.apache.dubbo.rpc.PathResolver;
import org.apache.dubbo.rpc.RpcException;
import org.apache.dubbo.rpc.ServerService;
import org.apache.dubbo.rpc.TriRpcStatus;
import org.apache.dubbo.rpc.model.MethodDescriptor;
import org.apache.dubbo.rpc.model.ServiceDescriptor;
import org.apache.dubbo.rpc.model.StubMethodDescriptor;
import org.apache.dubbo.rpc.model.StubServiceDescriptor;
import org.apache.dubbo.rpc.service.Destroyable;
import org.apache.dubbo.rpc.stub.BiStreamMethodHandler;
import org.apache.dubbo.rpc.stub.ServerStreamMethodHandler;
import org.apache.dubbo.rpc.stub.StubInvocationUtil;
import org.apache.dubbo.rpc.stub.StubInvoker;
import org.apache.dubbo.rpc.stub.StubMethodHandler;
import org.apache.dubbo.rpc.stub.StubSuppliers;
import org.apache.dubbo.rpc.stub.UnaryStubMethodHandler;

import com.google.protobuf.Message;

import java.util.HashMap;
import java.util.Map;
import java.util.function.BiConsumer;
import java.util.concurrent.CompletableFuture;

public final class {{className}} {

    public static final String SERVICE_NAME = {{interfaceClassName}}.SERVICE_NAME;

    private static final StubServiceDescriptor serviceDescriptor = new StubServiceDescriptor(SERVICE_NAME, {{interfaceClassName}}.class);

    static {
        org.apache.dubbo.rpc.protocol.tri.service.SchemaDescriptorRegistry.addSchemaDescriptor(SERVICE_NAME, {{outerClassName}}.getDescriptor());
        StubSuppliers.addSupplier(SERVICE_NAME, {{className}}::newStub);
        StubSuppliers.addSupplier({{interfaceClassName}}.JAVA_SERVICE_NAME,  {{className}}::newStub);
        StubSuppliers.addDescriptor(SERVICE_NAME, serviceDescriptor);
        StubSuppliers.addDescriptor({{interfaceClassName}}.JAVA_SERVICE_NAME, serviceDescriptor);
    }

    @SuppressWarnings("unchecked")
    public static {{interfaceClassName}} newStub(Invoker<?> invoker) {
        return new {{interfaceClassName}}Stub((Invoker<{{interfaceClassName}}>)invoker);
    }
{{#unaryMethods}}

    private static final StubMethodDescriptor {{methodName}}Method = new StubMethodDescriptor("{{originMethodName}}",
    {{inputType}}.class, {{outputType}}.class, MethodDescriptor.RpcType.UNARY,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);

    private static final StubMethodDescriptor {{methodName}}AsyncMethod = new StubMethodDescriptor("{{originMethodName}}",
    {{inputType}}.class, java.util.concurrent.CompletableFuture.class, MethodDescriptor.RpcType.UNARY,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);

    private static final StubMethodDescriptor {{methodName}}ProxyAsyncMethod = new StubMethodDescriptor("{{originMethodName}}Async",
    {{inputType}}.class, {{outputType}}.class, MethodDescriptor.RpcType.UNARY,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);
{{/unaryMethods}}
{{#serverStreamingMethods}}

    private static final StubMethodDescriptor {{methodName}}Method = new StubMethodDescriptor("{{originMethodName}}",
    {{inputType}}.class, {{outputType}}.class, MethodDescriptor.RpcType.SERVER_STREAM,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);
{{/serverStreamingMethods}}
{{#clientStreamingMethods}}

    private static final StubMethodDescriptor {{methodName}}Method = new StubMethodDescriptor("{{originMethodName}}",
    {{inputType}}.class, {{outputType}}.class, MethodDescriptor.RpcType.CLIENT_STREAM,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);
{{/clientStreamingMethods}}
{{#biStreamingWithoutClientStreamMethods}}

    private static final StubMethodDescriptor {{methodName}}Method = new StubMethodDescriptor("{{originMethodName}}",
    {{inputType}}.class, {{outputType}}.class, MethodDescriptor.RpcType.BI_STREAM,
    obj -> ((Message) obj).toByteArray(), obj -> ((Message) obj).toByteArray(), {{inputType}}::parseFrom,
    {{outputType}}::parseFrom);
{{/biStreamingWithoutClientStreamMethods}}

    static{
    {{#unaryMethods}}
        serviceDescriptor.addMethod({{methodName}}Method);
        serviceDescriptor.addMethod({{methodName}}ProxyAsyncMethod);
    {{/unaryMethods}}
    {{#serverStreamingMethods}}
        serviceDescriptor.addMethod({{methodName}}Method);
    {{/serverStreamingMethods}}
    {{#clientStreamingMethods}}
        serviceDescriptor.addMethod({{methodName}}Method);
    {{/clientStreamingMethods}}
    {{#biStreamingWithoutClientStreamMethods}}
        serviceDescriptor.addMethod({{methodName}}Method);
    {{/biStreamingWithoutClientStreamMethods}}
    }

    public static class {{interfaceClassName}}Stub implements {{interfaceClassName}}, Destroyable {
        private final Invoker<{{interfaceClassName}}> invoker;

        public {{interfaceClassName}}Stub(Invoker<{{interfaceClassName}}> invoker) {
            this.invoker = invoker;
        }

        @Override
        public void $destroy() {
              invoker.destroy();
         }
    {{#unaryMethods}}

        @Override
        public {{outputType}} {{methodName}}({{inputType}} request){
            return StubInvocationUtil.unaryCall(invoker, {{methodName}}Method, request);
        }

        public CompletableFuture<{{outputType}}> {{methodName}}Async({{inputType}} request){
            return StubInvocationUtil.unaryCall(invoker, {{methodName}}AsyncMethod, request);
        }

        public void {{methodName}}({{inputType}} request, StreamObserver<{{outputType}}> responseObserver){
            StubInvocationUtil.unaryCall(invoker, {{methodName}}Method , request, responseObserver);
        }
    {{/unaryMethods}}
    {{#serverStreamingMethods}}

        @Override
        public void {{methodName}}({{inputType}} request, StreamObserver<{{outputType}}> responseObserver){
            StubInvocationUtil.serverStreamCall(invoker, {{methodName}}Method , request, responseObserver);
        }
    {{/serverStreamingMethods}}
    {{#biStreamingWithoutClientStreamMethods}}

        @Override
        public StreamObserver<{{inputType}}> {{methodName}}(StreamObserver<{{outputType}}> responseObserver){
            return StubInvocationUtil.biOrClientStreamCall(invoker, {{methodName}}Method , responseObserver);
        }
    {{/biStreamingWithoutClientStreamMethods}}
    {{#clientStreamingMethods}}

        @Override
        public StreamObserver<{{inputType}}> {{methodName}}(StreamObserver<{{outputType}}> responseObserver){
        return StubInvocationUtil.biOrClientStreamCall(invoker, {{methodName}}Method , responseObserver);
        }
    {{/clientStreamingMethods}}
    }

    public static abstract class {{interfaceClassName}}ImplBase implements {{interfaceClassName}}, ServerService<{{interfaceClassName}}> {
        private <T, R> BiConsumer<T, StreamObserver<R>> syncToAsync(java.util.function.Function<T, R> syncFun) {
            return new BiConsumer<T, StreamObserver<R>>() {
                @Override
                public void accept(T t, StreamObserver<R> observer) {
                    try {
                        R ret = syncFun.apply(t);
                        observer.onNext(ret);
                        observer.onCompleted();
                    } catch (Throwable e) {
                        observer.onError(e);
                    }
                }
            };
        }
        {{#unaryMethods}}

        @Override
        public CompletableFuture<{{outputType}}> {{methodName}}Async({{inputType}} request){
                return CompletableFuture.completedFuture({{methodName}}(request));
        }
        {{/unaryMethods}}

        // This server stream type unary method is <b>only</b> used for generated stub to support async unary method.
        // It will not be called if you are NOT using Dubbo3 generated triple stub and <b>DO NOT</b> implement this method.
        {{#unaryMethods}}

        public void {{methodName}}({{inputType}} request, StreamObserver<{{outputType}}> responseObserver){
            {{methodName}}Async(request).whenComplete((r, t) -> {
                if (t != null) {
                    responseObserver.onError(t);
                } else {
                    responseObserver.onNext(r);
                    responseObserver.onCompleted();
                }
            });
        }
        {{/unaryMethods}}

        @Override
        public final Invoker<{{interfaceClassName}}> getInvoker(URL url) {
            PathResolver pathResolver = url.getOrDefaultFrameworkModel()
            .getExtensionLoader(PathResolver.class)
            .getDefaultExtension();
            Map<String, StubMethodHandler<?, ?>> handlers = new HashMap<>();
        {{#methods}}
            pathResolver.addNativeStub( "/" + SERVICE_NAME + "/{{originMethodName}}");
            pathResolver.addNativeStub( "/" + SERVICE_NAME + "/{{originMethodName}}Async");
            // for compatibility
            pathResolver.addNativeStub( "/" + JAVA_SERVICE_NAME + "/{{originMethodName}}");
            pathResolver.addNativeStub( "/" + JAVA_SERVICE_NAME + "/{{originMethodName}}Async");
        {{/methods}}
        {{#unaryMethods}}
            BiConsumer<{{inputType}}, StreamObserver<{{outputType}}>> {{methodName}}Func = this::{{methodName}};
            handlers.put({{methodName}}Method.getMethodName(), new UnaryStubMethodHandler<>({{methodName}}Func));
            BiConsumer<{{inputType}}, StreamObserver<{{outputType}}>> {{methodName}}AsyncFunc = syncToAsync(this::{{methodName}});
            handlers.put({{methodName}}ProxyAsyncMethod.getMethodName(), new UnaryStubMethodHandler<>({{methodName}}AsyncFunc));
        {{/unaryMethods}}
        {{#serverStreamingMethods}}
            handlers.put({{methodName}}Method.getMethodName(), new ServerStreamMethodHandler<>(this::{{methodName}}));
        {{/serverStreamingMethods}}
        {{#clientStreamingMethods}}
            handlers.put({{methodName}}Method.getMethodName(), new BiStreamMethodHandler<>(this::{{methodName}}));
        {{/clientStreamingMethods}}
        {{#biStreamingWithoutClientStreamMethods}}
            handlers.put({{methodName}}Method.getMethodName(), new BiStreamMethodHandler<>(this::{{methodName}}));
        {{/biStreamingWithoutClientStreamMethods}}

            return new StubInvoker<>(this, url, {{interfaceClassName}}.class, handlers);
        }
    {{#unaryMethods}}

        @Override
        public {{outputType}} {{methodName}}({{inputType}} request){
            throw unimplementedMethodException({{methodName}}Method);
        }
    {{/unaryMethods}}
    {{#serverStreamingMethods}}

        @Override
        public void {{methodName}}({{inputType}} request, StreamObserver<{{outputType}}> responseObserver){
            throw unimplementedMethodException({{methodName}}Method);
        }
    {{/serverStreamingMethods}}
    {{#biStreamingWithoutClientStreamMethods}}

        @Override
        public StreamObserver<{{inputType}}> {{methodName}}(StreamObserver<{{outputType}}> responseObserver){
            throw unimplementedMethodException({{methodName}}Method);
        }
    {{/biStreamingWithoutClientStreamMethods}}
    {{#clientStreamingMethods}}

        @Override
        public StreamObserver<{{inputType}}> {{methodName}}(StreamObserver<{{outputType}}> responseObserver){
            throw unimplementedMethodException({{methodName}}Method);
        }
    {{/clientStreamingMethods}}

        @Override
        public final ServiceDescriptor getServiceDescriptor() {
            return serviceDescriptor;
        }
        private RpcException unimplementedMethodException(StubMethodDescriptor methodDescriptor) {
            return TriRpcStatus.UNIMPLEMENTED.withDescription(String.format("Method %s is unimplemented",
                "/" + serviceDescriptor.getInterfaceName() + "/" + methodDescriptor.getMethodName())).asException();
        }
    }
}
