// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.vespa.hosted.controller.maintenance;

import com.yahoo.component.Version;
import com.yahoo.config.provision.ApplicationId;
import com.yahoo.config.provision.CloudAccount;
import com.yahoo.config.provision.zone.ZoneId;
import com.yahoo.jdisc.test.MockMetric;
import com.yahoo.vespa.flags.Flags;
import com.yahoo.vespa.flags.InMemoryFlagSource;
import com.yahoo.vespa.flags.PermanentFlags;
import com.yahoo.vespa.hosted.controller.ControllerTester;
import com.yahoo.vespa.hosted.controller.api.integration.certificates.EndpointCertificate;
import com.yahoo.vespa.hosted.controller.api.integration.certificates.EndpointCertificateDetails;
import com.yahoo.vespa.hosted.controller.api.integration.certificates.EndpointCertificateProviderMock;
import com.yahoo.vespa.hosted.controller.api.integration.certificates.EndpointCertificateRequest;
import com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType;
import com.yahoo.vespa.hosted.controller.api.integration.deployment.RevisionId;
import com.yahoo.vespa.hosted.controller.application.Deployment;
import com.yahoo.vespa.hosted.controller.application.DeploymentActivity;
import com.yahoo.vespa.hosted.controller.application.DeploymentMetrics;
import com.yahoo.vespa.hosted.controller.application.QuotaUsage;
import com.yahoo.vespa.hosted.controller.application.TenantAndApplicationId;
import com.yahoo.vespa.hosted.controller.certificate.AssignedCertificate;
import com.yahoo.vespa.hosted.controller.deployment.ApplicationPackageBuilder;
import com.yahoo.vespa.hosted.controller.deployment.DeploymentContext;
import com.yahoo.vespa.hosted.controller.deployment.DeploymentTester;
import com.yahoo.vespa.hosted.controller.integration.SecretStoreMock;
import com.yahoo.vespa.hosted.controller.routing.EndpointConfig;
import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.Test;

import java.time.Duration;
import java.time.Instant;
import java.time.temporal.ChronoUnit;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.OptionalDouble;
import java.util.stream.Stream;

import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.devUsEast1;
import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.perfUsEast3;
import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.productionUsCentral1;
import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.productionUsWest1;
import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.stagingTest;
import static com.yahoo.vespa.hosted.controller.deployment.DeploymentContext.systemTest;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;

/**
 * @author andreer
 */
public class EndpointCertificateMaintainerTest {

    private final ControllerTester tester = new ControllerTester();
    private final SecretStoreMock secretStore = (SecretStoreMock) tester.controller().secretStore();
    private final EndpointCertificateMaintainer maintainer = new EndpointCertificateMaintainer(tester.controller(), Duration.ofHours(1));
    private final CertificatePoolMaintainer certificatePoolMaintainer = new CertificatePoolMaintainer(tester.controller(), new MockMetric(), Duration.ofHours(1));
    private final EndpointCertificate exampleCert = new EndpointCertificate("keyName", "certName", 0, 0, "root-request-uuid", Optional.of("leaf-request-uuid"), List.of(), "issuer", Optional.empty(), Optional.empty(), Optional.empty());

    @Test
    void old_and_unused_cert_is_deleted() {
        tester.curator().writeAssignedCertificate(assignedCertificate(ApplicationId.defaultId(), exampleCert));
        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        assertTrue(tester.curator().readAssignedCertificate(ApplicationId.defaultId()).isEmpty());
    }

    @Test
    void unused_but_recently_used_cert_is_not_deleted() {
        EndpointCertificate recentlyRequestedCert = exampleCert.withLastRequested(tester.clock().instant().minusSeconds(3600).getEpochSecond());
        tester.curator().writeAssignedCertificate(assignedCertificate(ApplicationId.defaultId(), recentlyRequestedCert));
        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        assertEquals(Optional.of(recentlyRequestedCert), tester.curator().readAssignedCertificate(ApplicationId.defaultId()).map(AssignedCertificate::certificate));
    }

    @Test
    void refreshed_certificate_is_updated() {
        EndpointCertificate recentlyRequestedCert = exampleCert.withLastRequested(tester.clock().instant().minusSeconds(3600).getEpochSecond());
        tester.curator().writeAssignedCertificate(assignedCertificate(ApplicationId.defaultId(), recentlyRequestedCert));

        secretStore.setSecret(exampleCert.keyName(), "foo", 1);
        secretStore.setSecret(exampleCert.certName(), "bar", 1);

        assertEquals(0.0, maintainer.maintain(), 0.0000001);

        var updatedCert = Optional.of(recentlyRequestedCert.withLastRefreshed(tester.clock().instant().getEpochSecond()).withVersion(1));

        assertEquals(updatedCert, tester.curator().readAssignedCertificate(ApplicationId.defaultId()).map(AssignedCertificate::certificate));
    }

    @Test
    void certificate_in_use_is_not_deleted() {
        var appId = ApplicationId.from("tenant", "application", "default");

        DeploymentTester deploymentTester = new DeploymentTester(tester);

        var applicationPackage = new ApplicationPackageBuilder()
                .region("us-west-1")
                .build();

        DeploymentContext deploymentContext = deploymentTester.newDeploymentContext("tenant", "application", "default");

        deploymentContext.submit(applicationPackage).runJob(systemTest).runJob(stagingTest).runJob(productionUsWest1);

        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        var cert = tester.curator().readAssignedCertificate(appId).orElseThrow().certificate();
        tester.controller().serviceRegistry().endpointCertificateProvider().certificateDetails(cert.leafRequestId().get()); // cert should not be deleted, the app is deployed!
    }

    @Test
    void refreshed_certificate_is_discovered_and_after_four_days_deployed() {
        prepareCertificatePool(1);

        var instanceId = ApplicationId.from("tenant", "application", "default");
        var applicationId = TenantAndApplicationId.from(instanceId);

        DeploymentTester deploymentTester = new DeploymentTester(tester);

        var applicationPackage = new ApplicationPackageBuilder()
                .region("us-west-1")
                .container("default")
                .build();

        DeploymentContext deploymentContext = deploymentTester.newDeploymentContext("tenant", "application", "default");
        deploymentContext.submit(applicationPackage).runJob(systemTest).runJob(stagingTest).runJob(productionUsWest1);
        var assignedCertificate = tester.curator().readAssignedCertificate(applicationId, Optional.empty()).orElseThrow();

        // cert should not be deleted, the app is deployed!
        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        assertEquals(tester.curator().readAssignedCertificate(applicationId, Optional.empty()).map(c->c.certificate().rootRequestId()), Optional.of(assignedCertificate.certificate().rootRequestId()));
        tester.controller().serviceRegistry().endpointCertificateProvider().certificateDetails(assignedCertificate.certificate().rootRequestId());
        // TODO: Remove this line when we have removed assignment of randomized id to application certificates
        //assignedCertificate = tester.curator().readAssignedCertificate().orElseThrow();

        // This simulates a cert refresh performed 3 days later
        tester.clock().advance(Duration.ofDays(3));
        secretStore.setSecret(assignedCertificate.certificate().keyName(), "foo", 1);
        secretStore.setSecret(assignedCertificate.certificate().certName(), "bar", 1);
        tester.controller().serviceRegistry().endpointCertificateProvider().requestCaSignedCertificate("preprovisioned." + assignedCertificate.certificate().generatedId().get(), assignedCertificate.certificate().requestedDnsSans(), Optional.of(assignedCertificate.certificate()), "rsa_2048", false);

        // We should now pick up the new key and cert version + uuid, but not force trigger deployment yet
        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        deploymentContext.assertNotRunning(productionUsWest1);
        var updatedCert = tester.curator().readAssignedCertificate(applicationId, Optional.empty()).orElseThrow().certificate();
        assertNotEquals(assignedCertificate.certificate().leafRequestId().orElseThrow(), updatedCert.leafRequestId().orElseThrow());
        assertEquals(updatedCert.version(), assignedCertificate.certificate().version() + 1);

        // after another 4 days, we should force trigger deployment if it hasn't already happened
        tester.clock().advance(Duration.ofDays(4).plusSeconds(1));
        deploymentContext.assertNotRunning(productionUsWest1);
        assertEquals(0.0, maintainer.maintain(), 0.0000001);
        deploymentContext.assertRunning(productionUsWest1);
    }

    @Test
    void testEligibleSorting() {
        EndpointCertificateMaintainer.EligibleJob oldestDeployment = makeDeploymentAtAge(5);
        assertEquals(
                oldestDeployment,
                Stream.of(makeDeploymentAtAge(2), oldestDeployment, makeDeploymentAtAge(4)).min(maintainer.oldestFirst).get());
    }

    private EndpointCertificateMaintainer.EligibleJob makeDeploymentAtAge(int ageInDays) {
        var deployment = new Deployment(ZoneId.defaultId(), CloudAccount.empty, RevisionId.forProduction(1), Version.emptyVersion,
                                        Instant.now().minus(ageInDays, ChronoUnit.DAYS), DeploymentMetrics.none, DeploymentActivity.none, QuotaUsage.none, OptionalDouble.empty(), Map.of());
        return new EndpointCertificateMaintainer.EligibleJob(deployment, ApplicationId.defaultId(), JobType.prod("somewhere"));
    }

    @Test
    void unmaintained_cert_is_deleted() {
        EndpointCertificateProviderMock endpointCertificateProvider = (EndpointCertificateProviderMock) tester.controller().serviceRegistry().endpointCertificateProvider();

        var cert = endpointCertificateProvider.requestCaSignedCertificate("something", List.of("a", "b", "c"), Optional.empty(), "rsa_2048", false);// Unknown to controller!

        assertEquals(0.0, maintainer.maintain(), 0.0000001);

        assertTrue(endpointCertificateProvider.dnsNamesOf(cert.rootRequestId()).isEmpty());
        assertTrue(endpointCertificateProvider.listCertificates().isEmpty());
    }

    @Test
    void cert_pool_is_not_deleted() {
        EndpointCertificateProviderMock endpointCertificateProvider = (EndpointCertificateProviderMock) tester.controller().serviceRegistry().endpointCertificateProvider();

        tester.flagSource().withIntFlag(PermanentFlags.CERT_POOL_SIZE.id(), 3);
        assertEquals(0.0, certificatePoolMaintainer.maintain(), 0.0000001);
        assertEquals(0.0, maintainer.maintain(), 0.0000001);

        assertNotEquals(List.of(), endpointCertificateProvider.listCertificates());
    }

    @Test
    void deploy_to_other_manual_zone_refreshes_cert() {
        String devSan = "*.foo.manual.tenant.us-east-1.dev.vespa.oath.cloud";
        String perfSan = "*.foo.manual.tenant.us-east-3.perf.vespa.oath.cloud";

        var devApp = ApplicationId.from("tenant", "manual", "foo");
        DeploymentTester deploymentTester = new DeploymentTester(tester);
        deployToAssignCert(deploymentTester, devApp, List.of(devUsEast1), Optional.empty());
        assertEquals(1, tester.curator().readAssignedCertificates().size());
        maintainer.maintain();
        Optional<AssignedCertificate> devCertificate = tester.curator().readAssignedCertificate(TenantAndApplicationId.from(devApp), Optional.of(devApp.instance()));
        List<String> devSans = devCertificate.get().certificate().requestedDnsSans();
        Assertions.assertThat(devSans).contains(devSan);
        Assertions.assertThat(devSans).doesNotContain(perfSan);

        // Deploy to perf and verify that the certs are refreshed
        deployToAssignCert(deploymentTester, devApp, List.of(perfUsEast3), Optional.empty());
        Optional<AssignedCertificate> devAndPerfCertificate = tester.curator().readAssignedCertificate(TenantAndApplicationId.from(devApp), Optional.of(devApp.instance()));
        List<String> devAndPerfSans = devAndPerfCertificate.get().certificate().requestedDnsSans();

        assertNotEquals(devSans, devAndPerfSans);
        Assertions.assertThat(devAndPerfSans).contains(devSan);
        Assertions.assertThat(devAndPerfSans).contains(perfSan);
    }

    @Test
    void deploy_to_other_prod_zone_refreshes_cert() {
        String westSan = "*.prod.tenant.us-west-1.vespa.oath.cloud";
        String centralSan = "*.prod.tenant.us-central-1.vespa.oath.cloud";

        var prodApp = ApplicationId.from("tenant", "prod", "default");
        DeploymentTester deploymentTester = new DeploymentTester(tester);
        deployToAssignCert(deploymentTester, prodApp, List.of(systemTest, stagingTest, productionUsWest1), Optional.empty());
        assertEquals(1, tester.curator().readAssignedCertificates().size());
        maintainer.maintain();
        Optional<AssignedCertificate> usWestCert = tester.curator().readAssignedCertificate(TenantAndApplicationId.from(prodApp), Optional.of(prodApp.instance()));
        List<String> usWestSans = usWestCert.get().certificate().requestedDnsSans();
        Assertions.assertThat(usWestSans).contains(westSan);
        Assertions.assertThat(usWestSans).doesNotContain(centralSan);

        // Deploy to perf and verify that the certs are refreshed
        deployToAssignCert(deploymentTester, prodApp, List.of(systemTest, stagingTest, productionUsWest1, productionUsCentral1), Optional.empty());
        Optional<AssignedCertificate> usCentralWestCert = tester.curator().readAssignedCertificate(TenantAndApplicationId.from(prodApp), Optional.of(prodApp.instance()));
        List<String> usCentralWestSans = usCentralWestCert.get().certificate().requestedDnsSans();
        assertNotEquals(usWestSans, usCentralWestSans);
        Assertions.assertThat(usCentralWestSans).contains(westSan);
        Assertions.assertThat(usCentralWestSans).contains(centralSan);
    }

    private void deployToAssignCert(DeploymentTester tester, ApplicationId applicationId, List<JobType> jobTypes, Optional<String> instances) {

        var applicationPackageBuilder = new ApplicationPackageBuilder();
        jobTypes.stream().filter(JobType::isProduction).map(job -> job.zone().region().value()).forEach(applicationPackageBuilder::region);

        instances.map(applicationPackageBuilder::instances);
        var applicationPackage = applicationPackageBuilder.build();

        List<JobType> manualJobs = jobTypes.stream().filter(jt -> jt.environment().isManuallyDeployed()).toList();
        List<JobType> jobs = jobTypes.stream().filter(jt -> ! jt.environment().isManuallyDeployed()).toList();

        DeploymentContext deploymentContext = tester.newDeploymentContext(applicationId);
        deploymentContext.submit(applicationPackage);
        manualJobs.forEach(job -> deploymentContext.runJob(job, applicationPackage));
        jobs.forEach(deploymentContext::runJob);

    }

    private static AssignedCertificate assignedCertificate(ApplicationId instance, EndpointCertificate certificate) {
        return new AssignedCertificate(TenantAndApplicationId.from(instance), Optional.of(instance.instance()), certificate, false);
    }

    private void prepareCertificatePool(int numCertificates) {
        ((InMemoryFlagSource) tester.controller().flagSource()).withIntFlag(PermanentFlags.CERT_POOL_SIZE.id(), numCertificates);
        ((InMemoryFlagSource) tester.controller().flagSource()).withStringFlag(Flags.ENDPOINT_CONFIG.id(), EndpointConfig.generated.name());

        // Provision certificates
        for (int i = 0; i < numCertificates; i++) {
            certificatePoolMaintainer.maintain();
        }

        // Make certificate ready
        EndpointCertificateProviderMock endpointCertificateProvider = (EndpointCertificateProviderMock) tester.controller().serviceRegistry().endpointCertificateProvider();
        List<EndpointCertificateRequest> endpointCertificateRequests = endpointCertificateProvider.listCertificates();
        endpointCertificateRequests.forEach(cert -> {
            EndpointCertificateDetails details = endpointCertificateProvider.certificateDetails(cert.requestId());
            secretStore.setSecret(details.privateKeyKeyname(), "foo", 0);
            secretStore.setSecret(details.certKeyKeyname(), "bar", 0);
        });
        certificatePoolMaintainer.maintain();
    }

}