package ca.uhn.fhir.jpa.starter;

import ca.uhn.fhir.context.FhirContext;
import ca.uhn.fhir.rest.api.CacheControlDirective;
import ca.uhn.fhir.rest.api.EncodingEnum;
import ca.uhn.fhir.rest.api.MethodOutcome;
import ca.uhn.fhir.rest.client.api.IGenericClient;
import ca.uhn.fhir.rest.client.api.ServerValidationModeEnum;
import ca.uhn.fhir.rest.client.interceptor.LoggingInterceptor;
import ca.uhn.fhir.util.BundleUtil;
import org.eclipse.jetty.websocket.api.Session;
import org.eclipse.jetty.websocket.client.ClientUpgradeRequest;
import org.eclipse.jetty.websocket.client.WebSocketClient;
import org.hl7.fhir.instance.model.api.IIdType;
import org.hl7.fhir.r4.model.*;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.web.server.LocalServerPort;
import org.springframework.test.context.junit.jupiter.SpringExtension;

import java.net.URI;
import java.util.Collection;
import java.util.List;
import java.util.Optional;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

import static ca.uhn.fhir.util.TestUtil.waitForSize;
import static org.awaitility.Awaitility.await;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;

@ExtendWith(SpringExtension.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT, classes = Application.class, properties =
  {
    "spring.batch.job.enabled=false",
    "spring.profiles.active=r5",
    "spring.datasource.url=jdbc:h2:mem:dbr5",
    "hapi.fhir.subscription.websocket_enabled=true",
    "hapi.fhir.empi_enabled=true"
  })
public class ExampleServerR4IT {

  private static final org.slf4j.Logger ourLog = org.slf4j.LoggerFactory.getLogger(ExampleServerDstu2IT.class);
  private IGenericClient ourClient;
  private FhirContext ourCtx;

  @LocalServerPort
  private int port;


  @Test
  void testCreateAndRead() {

    String methodName = "testCreateResourceConditional";

    Patient pt = new Patient();
    pt.setActive(true);
    pt.getBirthDateElement().setValueAsString("2020-01-01");
    pt.addIdentifier().setSystem("http://foo").setValue("12345");
    pt.addName().setFamily(methodName);
    IIdType id = ourClient.create().resource(pt).execute().getId();

    Patient pt2 = ourClient.read().resource(Patient.class).withId(id).execute();
    assertEquals(methodName, pt2.getName().get(0).getFamily());

    // Test EMPI

    // Wait until the EMPI message has been processed
    await().until(() -> getPeople().size() > 0);
    List<Person> persons = getPeople();

    // Verify a Person was created that links to our Patient
    Optional<String> personLinkToCreatedPatient = persons.stream()
      .map(Person::getLink)
      .flatMap(Collection::stream)
      .map(Person.PersonLinkComponent::getTarget)
      .map(Reference::getReference)
      .filter(pid -> id.toUnqualifiedVersionless().getValue().equals(pid))
      .findAny();
    assertTrue(personLinkToCreatedPatient.isPresent());
  }

  private List<Person> getPeople() {
    Bundle bundle = ourClient.search().forResource(Person.class).cacheControl(new CacheControlDirective().setNoCache(true)).returnBundle(Bundle.class).execute();
    return BundleUtil.toListOfResourcesOfType(ourCtx, bundle, Person.class);
  }

  @Test
  public void testWebsocketSubscription() throws Exception {
    /*
     * Create subscription
     */
    Subscription subscription = new Subscription();
    subscription.setReason("Monitor new neonatal function (note, age will be determined by the monitor)");
    subscription.setStatus(Subscription.SubscriptionStatus.REQUESTED);
    subscription.setCriteria("Observation?status=final");

    Subscription.SubscriptionChannelComponent channel = new Subscription.SubscriptionChannelComponent();
    channel.setType(Subscription.SubscriptionChannelType.WEBSOCKET);
    channel.setPayload("application/json");
    subscription.setChannel(channel);

    MethodOutcome methodOutcome = ourClient.create().resource(subscription).execute();
    IIdType mySubscriptionId = methodOutcome.getId();

    // Wait for the subscription to be activated
    await().until(() -> activeSubscriptionCount() == 3);

    /*
     * Attach websocket
     */

    WebSocketClient myWebSocketClient = new WebSocketClient();
    SocketImplementation mySocketImplementation = new SocketImplementation(mySubscriptionId.getIdPart(), EncodingEnum.JSON);

    myWebSocketClient.start();
    URI echoUri = new URI("ws://localhost:" + port + "/hapi-fhir-jpaserver/websocket");
    ClientUpgradeRequest request = new ClientUpgradeRequest();
    ourLog.info("Connecting to : {}", echoUri);
    Future<Session> connection = myWebSocketClient.connect(mySocketImplementation, echoUri, request);
    Session session = connection.get(2, TimeUnit.SECONDS);

    ourLog.info("Connected to WS: {}", session.isOpen());

    /*
     * Create a matching resource
     */
    Observation obs = new Observation();
    obs.setStatus(Observation.ObservationStatus.FINAL);
    ourClient.create().resource(obs).execute();

    // Give some time for the subscription to deliver
    Thread.sleep(2000);

    /*
     * Ensure that we receive a ping on the websocket
     */
    waitForSize(1, () -> mySocketImplementation.myPingCount);

    /*
     * Clean up
     */
    ourClient.delete().resourceById(mySubscriptionId).execute();
  }

  private int activeSubscriptionCount() {
    return ourClient.search().forResource(Subscription.class).where(Subscription.STATUS.exactly().code("active")).cacheControl(new CacheControlDirective().setNoCache(true)).returnBundle(Bundle.class).execute().getEntry().size();
  }


  @BeforeEach
  void beforeEach() {

    ourCtx = FhirContext.forR4();
    ourCtx.getRestfulClientFactory().setServerValidationMode(ServerValidationModeEnum.NEVER);
    ourCtx.getRestfulClientFactory().setSocketTimeout(1200 * 1000);
    String ourServerBase = "http://localhost:" + port + "/hapi-fhir-jpaserver/fhir/";
    ourClient = ourCtx.newRestfulGenericClient(ourServerBase);
    ourClient.registerInterceptor(new LoggingInterceptor(true));
  }
}