package com.ankurm.protocols;

import com.ankurm.protocols.grpc.QuoteRequest;
import com.ankurm.protocols.grpc.QuoteServiceGrpc;
import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.web.server.LocalServerPort;
import org.springframework.messaging.rsocket.RSocketRequester;
import org.springframework.messaging.rsocket.RSocketStrategies;

import java.util.concurrent.TimeUnit;

import static org.assertj.core.api.Assertions.assertThat;

/**
 * Sequential request/response round trips, all three protocols, same JVM, same data source.
 *
 * <p>Read the numbers as a comparison of the three, not as absolutes. Client and server are the
 * same process on one loopback interface with two cores, so the network &mdash; the thing that
 * dominates every real deployment &mdash; is absent. That deletes the advantage a smaller
 * encoding would have on a real link and leaves framing and dispatch cost, which is exactly the
 * part a loopback measures well.
 */
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,
        properties = {"spring.rsocket.server.port=7001", "spring.grpc.server.port=9091"})
class RequestResponseBenchmarkTest {

    private static final int WARMUP = 2_000;
    private static final int MEASURED = 5_000;

    @LocalServerPort
    int httpPort;

    @Autowired
    RSocketStrategies strategies;

    @Test
    void threeProtocolsOneOperation() throws Exception {
        System.out.println("=== request/response, " + MEASURED + " sequential calls after "
                + WARMUP + " warm-up, loopback, JDK " + System.getProperty("java.version") + " ===");
        System.out.println(grpc());
        System.out.println(rsocket());
        System.out.println(websocket());
    }

    private String grpc() {
        ManagedChannel channel = ManagedChannelBuilder.forAddress("localhost", 9091)
                .usePlaintext().build();
        try {
            var stub = QuoteServiceGrpc.newBlockingStub(channel);
            QuoteRequest req = QuoteRequest.newBuilder().setSymbol("AAPL").build();
            for (int i = 0; i < WARMUP; i++) {
                stub.getQuote(req);
            }
            Bench bench = new Bench(MEASURED);
            for (int i = 0; i < MEASURED; i++) {
                long t0 = System.nanoTime();
                var quote = stub.getQuote(req);
                bench.record(System.nanoTime() - t0);
                assertThat(quote.getSymbol()).isEqualTo("AAPL");
            }
            return bench.summary("gRPC");
        }
        finally {
            channel.shutdownNow();
        }
    }

    private String rsocket() {
        RSocketRequester requester = RSocketRequester.builder()
                .rsocketStrategies(strategies).tcp("localhost", 7001);
        try {
            for (int i = 0; i < WARMUP; i++) {
                requester.route("quote").data("AAPL").retrieveMono(Quote.class).block();
            }
            Bench bench = new Bench(MEASURED);
            for (int i = 0; i < MEASURED; i++) {
                long t0 = System.nanoTime();
                Quote quote = requester.route("quote").data("AAPL")
                        .retrieveMono(Quote.class).block();
                bench.record(System.nanoTime() - t0);
                assertThat(quote).isNotNull();
            }
            return bench.summary("RSocket");
        }
        finally {
            requester.dispose();
        }
    }

    private String websocket() throws Exception {
        try (WsClient client = new WsClient(httpPort, 64)) {
            for (int i = 0; i < WARMUP; i++) {
                client.send("QUOTE AAPL");
                assertThat(client.take(5_000)).isNotNull();
            }
            Bench bench = new Bench(MEASURED);
            for (int i = 0; i < MEASURED; i++) {
                long t0 = System.nanoTime();
                client.send("QUOTE AAPL");
                String reply = client.take(5_000);
                bench.record(System.nanoTime() - t0);
                assertThat(reply).contains("AAPL");
            }
            return bench.summary("WebSocket");
        }
    }
}