const role = new aws_iam.Role(this, 'RoleForLambdaIcaServerlessDemo', {
  assumedBy: new aws_iam.ServicePrincipal('lambda.amazonaws.com'),
  roleName: 'RoleForLambdaIcaServerlessDemo'
})

// inline policies
role.attachInlinePolicy(
  new aws_iam.Policy(this, 'PolicyForLambdaIcaServerlessDemo', {
    policyName: 'PolicyForLambdaIcaServerlessDemo',
    statements: [
      // acces s3
      new aws_iam.PolicyStatement({
        effect: aws_iam.Effect.ALLOW,
        actions: ['s3:*', 's3-object-lambda:*'],
        resources: ['arn:aws:s3:::haimtran-workspace/*']
      }),

      // write to dynamo db
      new aws_iam.PolicyStatement({
        effect: aws_iam.Effect.ALLOW,
        actions: ['dynamodb:*'],
        resources: ['*']
      }),

      // send sns
      new aws_iam.PolicyStatement({
        effect: aws_iam.Effect.ALLOW,
        actions: ['sns:*'],
        resources: ['*']
      })
    ]
  })
)

const func = new aws_lambda.Function(this, 'CdkLambdaIcaDemo', {
  functionName: 'CdkLambdaIcaDemo',
  runtime: aws_lambda.Runtime.PYTHON_3_8,
  memorySize: 512,
  timeout: Duration.seconds(15),
  code: aws_lambda.Code.fromAsset(path.join(__dirname, './../lambda')),
  handler: 'lambda_write_ddb.handler',
  role: role
})

const lambda_sns = new aws_lambda.Function(this, 'IcaLambdaSnsDemo', {
  functionName: 'LambdaSnsIcaDemo',
  code: aws_lambda.Code.fromAsset(path.join(__dirname, './../lambda')),
  handler: 'lambda_send_sns.handler',
  runtime: aws_lambda.Runtime.PYTHON_3_8,
  role: role
})

// an existed s3 trigger a lambda
const bucket = aws_s3.Bucket.fromBucketName(
  this,
  'haimtran-bucket-id',
  'haimtran-workspace'
)

bucket.addEventNotification(
  aws_s3.EventType.OBJECT_CREATED,
  new aws_s3_notifications.LambdaDestination(func),
  {
    prefix: 'notify-lambda/'
  }
)

const table = new aws_dynamodb.Table(this, 'S3LambdaEventTable', {
  tableName: 'S3LambdaEventTable',
  partitionKey: {
    name: 'id',
    type: aws_dynamodb.AttributeType.STRING
  },
  billingMode: aws_dynamodb.BillingMode.PAY_PER_REQUEST,
  stream: aws_dynamodb.StreamViewType.NEW_IMAGE
})

lambda_sns.addEventSource(
  new aws_lambda_event_sources.DynamoEventSource(table, {
    startingPosition: aws_lambda.StartingPosition.LATEST,
    batchSize: 1,
    retryAttempts: 2
  })
)

// create a sns topic
const topic = new aws_sns.Topic(this, 'SnsTopicIcaDemo', {
  topicName: 'SnsTopicIcaDemo'
})

// subscript
topic.addSubscription(
  new aws_sns_subscriptions.EmailSubscription('hai@entest.io')
)