/* 
   Example from:
     https://cloud.google.com/compute/docs/samples/compute-instances-create#compute_instances_create-java
*/

import com.google.api.gax.longrunning.OperationFuture;
import com.google.cloud.compute.v1.AttachedDisk;
import com.google.cloud.compute.v1.AttachedDisk.Type;
import com.google.cloud.compute.v1.AttachedDiskInitializeParams;
import com.google.cloud.compute.v1.InsertInstanceRequest;
import com.google.cloud.compute.v1.Instance;
import com.google.cloud.compute.v1.InstancesClient;
import com.google.cloud.compute.v1.NetworkInterface;
import com.google.cloud.compute.v1.Operation;
import java.io.IOException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class CreateInstance {

  public static void main(String[] args)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    // TODO(developer): Replace these variables before running the sample.
    String project = "your-project-id";
    String zone = "zone-name";
    String instanceName = "instance-name";
    createInstance(project, zone, instanceName);
  }


  // Create a new instance with the provided "instanceName" value in the specified project and zone.
  public static void createInstance(String project, String zone, String instanceName)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    // Below are sample values that can be replaced.
    // machineType: machine type of the VM being created.
    // *   This value uses the format zones/{zone}/machineTypes/{type_name}.
    // *   For a list of machine types, see https://cloud.google.com/compute/docs/machine-types
    // sourceImage: path to the operating system image to mount.
    // *   For details about images you can mount, see https://cloud.google.com/compute/docs/images
    // diskSizeGb: storage size of the boot disk to attach to the instance.
    // networkName: network interface to associate with the instance.
    String machineType = String.format("zones/%s/machineTypes/n1-standard-1", zone);
    String sourceImage = String
        .format("projects/debian-cloud/global/images/family/%s", "debian-11");
    long diskSizeGb = 10L;
    String networkName = "default";

    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests. After completing all of your requests, call
    // the `instancesClient.close()` method on the client to safely
    // clean up any remaining background resources.
    try (InstancesClient instancesClient = InstancesClient.create()) {
      // Instance creation requires at least one persistent disk and one network interface.
      AttachedDisk disk =
          AttachedDisk.newBuilder()
              .setBoot(true)
              .setAutoDelete(true)
              .setType(Type.PERSISTENT.toString())
              .setDeviceName("disk-1")
              .setInitializeParams(
                  AttachedDiskInitializeParams.newBuilder()
                      .setSourceImage(sourceImage)
                      .setDiskSizeGb(diskSizeGb)
                      .build())
              .build();

      // Use the network interface provided in the networkName argument.
      NetworkInterface networkInterface = NetworkInterface.newBuilder()
          .setName(networkName)
          .build();

      // Bind `instanceName`, `machineType`, `disk`, and `networkInterface` to an instance.
      Instance instanceResource =
          Instance.newBuilder()
              .setName(instanceName)
              .setMachineType(machineType)
              .addDisks(disk)
              .addNetworkInterfaces(networkInterface)
              .build();

      System.out.printf("Creating instance: %s at %s %n", instanceName, zone);

      // Insert the instance in the specified project and zone.
      InsertInstanceRequest insertInstanceRequest = InsertInstanceRequest.newBuilder()
          .setProject(project)
          .setZone(zone)
          .setInstanceResource(instanceResource)
          .build();

      OperationFuture<Operation, Operation> operation = instancesClient.insertAsync(
          insertInstanceRequest);

      // Wait for the operation to complete.
      Operation response = operation.get(3, TimeUnit.MINUTES);

      if (response.hasError()) {
        System.out.println("Instance creation failed ! ! " + response);
        return;
      }
      System.out.println("Operation Status: " + response.getStatus());
    }
  }
}