/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: MIT-0
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this
 * software and associated documentation files (the "Software"), to deal in the Software
 * without restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

package com.amazon;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import software.amazon.awscdk.CfnOutput;
import software.amazon.awscdk.RemovalPolicy;
import software.amazon.awscdk.Stack;
import software.amazon.awscdk.StackProps;
import software.amazon.awscdk.cdk.lambdalayer.kubectl.v24.KubectlV24Layer;
import software.amazon.awscdk.services.autoscaling.AutoScalingGroup;
import software.amazon.awscdk.services.autoscaling.UpdatePolicy;
import software.amazon.awscdk.services.dynamodb.Attribute;
import software.amazon.awscdk.services.dynamodb.AttributeType;
import software.amazon.awscdk.services.dynamodb.Table;
import software.amazon.awscdk.services.ec2.InstanceClass;
import software.amazon.awscdk.services.ec2.InstanceSize;
import software.amazon.awscdk.services.ec2.InstanceType;
import software.amazon.awscdk.services.ec2.Vpc;
import software.amazon.awscdk.services.ecr.Repository;
import software.amazon.awscdk.services.eks.AlbControllerOptions;
import software.amazon.awscdk.services.eks.AlbControllerVersion;
import software.amazon.awscdk.services.eks.AutoScalingGroupOptions;
import software.amazon.awscdk.services.eks.Cluster;
import software.amazon.awscdk.services.eks.ClusterLoggingTypes;
import software.amazon.awscdk.services.eks.EksOptimizedImage;
import software.amazon.awscdk.services.eks.HelmChartOptions;
import software.amazon.awscdk.services.eks.KubernetesManifest;
import software.amazon.awscdk.services.eks.KubernetesVersion;
import software.amazon.awscdk.services.eks.NodeType;
import software.amazon.awscdk.services.eks.ServiceAccount;
import software.amazon.awscdk.services.eks.ServiceAccountOptions;
import software.amazon.awscdk.services.events.EventBus;
import software.constructs.Construct;

public class QuarkusEksStack extends Stack {

  static Map<String, ? extends Object> namespaceManifestConfig = Map.of(
      "apiVersion", "v1",
      "kind", "Namespace",
      "metadata", Map.of(
          "name", "quarkus"
                        )
                                                                       );

  static String metricsServerConfig = "{\n" +
      "\"resources\": {\n" +
      "    \"requests\": {\n" +
      "        \"cpu\": \"0.25\",\n" +
      "        \"memory\": \"0.5Gi\"\n" +
      "    }\n" +
      "}\n" +
      "}";

  public QuarkusEksStack(final Construct scope, final String id) {
    this(scope, id, null);
  }

  public QuarkusEksStack(final Construct scope, final String id, final StackProps props) {
    super(scope, id, props);

    // First we need to create a VPC
    Vpc vpc = Vpc.Builder
        .create(this, "QuarkusEKSVpc")
        .vpcName("QuarkusEKSVPC")
        .build();

    // Second step is to create the EKS cluster
    Cluster eksCluster = Cluster.Builder
        .create(this, "Cluster")
        .clusterName("QuarkusEKSCluster")
        .vpc(vpc)
        .defaultCapacity(0)
        .clusterLogging(Arrays.asList(ClusterLoggingTypes.API,
                                      ClusterLoggingTypes.AUDIT,
                                      ClusterLoggingTypes.AUTHENTICATOR,
                                      ClusterLoggingTypes.CONTROLLER_MANAGER,
                                      ClusterLoggingTypes.SCHEDULER))
        .version(KubernetesVersion.V1_24)
        .outputClusterName(true)
        .outputConfigCommand(true)
        .outputMastersRoleArn(true)
        .kubectlLayer(new KubectlV24Layer(this, "kubectl"))
        .albController(AlbControllerOptions
                           .builder()
                           .version(
                               AlbControllerVersion.V2_4_1)
                           .build())
        .build();

    // Of course we need an ASG
    AutoScalingGroup eksAsg = AutoScalingGroup.Builder
        .create(this, "QuarkusEKSASG")
        .autoScalingGroupName("QuarkusEKSASG")
        .vpc(vpc)
        .minCapacity(3)
        .maxCapacity(9)
        .instanceType(
            InstanceType.of(InstanceClass.BURSTABLE3,
                            InstanceSize.MEDIUM))
        .machineImage(
            EksOptimizedImage.Builder
                .create()
                .kubernetesVersion(
                    KubernetesVersion.V1_24.getVersion())
                .nodeType(
                    NodeType.STANDARD)
                .build())
        .updatePolicy(UpdatePolicy.rollingUpdate())
        .build();

    eksCluster.connectAutoScalingGroupCapacity(eksAsg, AutoScalingGroupOptions
        .builder()
        .build());

    // And a service account for pod permissions

    KubernetesManifest manifest = KubernetesManifest.Builder
        .create(this, "read-only")
        .cluster(eksCluster)
        .manifest(
            List.of(namespaceManifestConfig))
        .build();

    Map<String, Object> metricsServerMap = null;
    try {
      metricsServerMap = new ObjectMapper().readValue(metricsServerConfig, HashMap.class);
    }
    catch (JsonProcessingException e) {
      e.printStackTrace();
    }

    // Now let's install metrics-server for HPA

    HelmChartOptions helmChartOptionsMetricsServer = HelmChartOptions
        .builder()
        .chart("metrics-server")
        .version("3.8.3")
        .release("metricsserver")
        .repository(
            "https://kubernetes-sigs.github.io/metrics-server/")
        .namespace("kube-system")
        .values(metricsServerMap)
        .wait(true)
        .build();

    eksCluster.addHelmChart("metrics-server",
                            helmChartOptionsMetricsServer);

    ServiceAccountOptions serviceAccountOptions = ServiceAccountOptions
        .builder()
        .namespace("quarkus")
        .name("serviceaccount.quarkus.amazon.com")
        .build();

    ServiceAccount serviceAccount = eksCluster.addServiceAccount("sa",
                                                                 serviceAccountOptions);
    serviceAccount
        .getNode()
        .addDependency(manifest);

    // Now we need to create a DynamoDB table
    Table table = Table.Builder
        .create(this, "QuarkusEksTable")
        .partitionKey(Attribute
                          .builder()
                          .name("Id")
                          .type(AttributeType.STRING)
                          .build())
        .tableName("Customer")
        .readCapacity(5)
        .writeCapacity(5)
        .removalPolicy(RemovalPolicy.DESTROY)
        .build();

    table.grantReadWriteData(serviceAccount);

    // And we need to create an EventBridge EventBus
    EventBus eventBus = EventBus.Builder
        .create(this, "QuarkusEksBus")
        .eventBusName("com.amazon.customerservice")
        .build();

    eventBus.grantPutEventsTo(serviceAccount);

    Repository ecrRepo = Repository.Builder
        .create(this, "QuarkusEcrRepo")
        .repositoryName("aws-eks-quarkus-example")
        .imageScanOnPush(true)
        .removalPolicy(RemovalPolicy.RETAIN)
        .build();

    CfnOutput.Builder
        .create(this, "Cluster name")
        .value(eksCluster.getClusterName())
        .build();
    CfnOutput.Builder
        .create(this, "ECR Repository")
        .value(ecrRepo.getRepositoryName());
  }
}