const {
  LightsailClient,
  GetInstancesCommand,
  GetInstanceCommand,
  StartInstanceCommand,
  StopInstanceCommand,
  RebootInstanceCommand,
  CreateInstancesCommand,
  DeleteInstanceCommand,
  CreateInstanceSnapshotCommand,
  GetInstanceSnapshotsCommand,
  DeleteInstanceSnapshotCommand,
} = require('@aws-sdk/client-lightsail');

function getConfig() {
  const region = process.env.AWS_REGION;
  const accessKeyId = process.env.AWS_ACCESS_KEY_ID;
  const secretAccessKey = process.env.AWS_SECRET_ACCESS_KEY;
  if (!region || !accessKeyId || !secretAccessKey) {
    throw new Error('AWS_REGION / AWS_ACCESS_KEY_ID / AWS_SECRET_ACCESS_KEY が設定されていません');
  }
  return { region, accessKeyId, secretAccessKey };
}

function getClient() {
  const { region, accessKeyId, secretAccessKey } = getConfig();
  return new LightsailClient({ region, credentials: { accessKeyId, secretAccessKey } });
}

async function listInstances(client = getClient()) {
  const res = await client.send(new GetInstancesCommand({}));
  return res.instances;
}

async function getInstance(instanceName, client = getClient()) {
  const res = await client.send(new GetInstanceCommand({ instanceName }));
  return res.instance;
}

async function startInstance(instanceName, client = getClient()) {
  const res = await client.send(new StartInstanceCommand({ instanceName }));
  return res.operations;
}

async function stopInstance(instanceName, client = getClient()) {
  const res = await client.send(new StopInstanceCommand({ instanceName }));
  return res.operations;
}

async function rebootInstance(instanceName, client = getClient()) {
  const res = await client.send(new RebootInstanceCommand({ instanceName }));
  return res.operations;
}

async function createInstance({ instanceName, availabilityZone, blueprintId, bundleId }, client = getClient()) {
  const res = await client.send(new CreateInstancesCommand({
    instanceNames: [instanceName],
    availabilityZone,
    blueprintId,
    bundleId,
  }));
  return res.operations;
}

async function deleteInstance(instanceName, client = getClient()) {
  const res = await client.send(new DeleteInstanceCommand({ instanceName }));
  return res.operations;
}

async function createSnapshot(instanceName, snapshotName, client = getClient()) {
  const res = await client.send(new CreateInstanceSnapshotCommand({
    instanceSnapshotName: snapshotName,
    instanceName,
  }));
  return res.operations;
}

async function listSnapshots(client = getClient()) {
  const res = await client.send(new GetInstanceSnapshotsCommand({}));
  return res.instanceSnapshots;
}

async function deleteSnapshot(snapshotName, client = getClient()) {
  const res = await client.send(new DeleteInstanceSnapshotCommand({ instanceSnapshotName: snapshotName }));
  return res.operations;
}

module.exports = {
  getConfig,
  getClient,
  listInstances,
  getInstance,
  startInstance,
  stopInstance,
  rebootInstance,
  createInstance,
  deleteInstance,
  createSnapshot,
  listSnapshots,
  deleteSnapshot,
};