// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
// snippet-start:[s3.go.list_objects]
package main

// snippet-start:[s3.go.list_objects.imports]
import (
	"flag"
	"fmt"

	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3"
)

// snippet-end:[s3.go.list_objects.imports]

// GetObjects retrieves the objects in an Amazon S3 bucket
// Inputs:
//
//	sess is the current session, which provides configuration for the SDK's service clients
//	bucket is the name of the bucket
//
// Output:
//
//	If success, the list of objects and nil
//	Otherwise, nil and an error from the call to ListObjectsV2
func GetObjects(sess *session.Session, bucket *string) (*s3.ListObjectsV2Output, error) {
	// snippet-start:[s3.go.list_objects.call]
	svc := s3.New(sess)

	// Get the list of items
	resp, err := svc.ListObjectsV2(&s3.ListObjectsV2Input{Bucket: bucket})
	// snippet-end:[s3.go.list_objects.call]
	if err != nil {
		return nil, err
	}

	return resp, nil
}

// Lists the items in the specified S3 bucket
//
// Usage:
//
//	go run s3_list_objects.go BUCKET_NAME
func main() {
	// snippet-start:[s3.go.list_objects.args]
	bucket := flag.String("b", "", "The name of the bucket")
	flag.Parse()

	if *bucket == "" {
		fmt.Println("You must supply the name of a bucket (-b BUCKET)")
		return
	}
	// snippet-end:[s3.go.list_objects.args]

	// snippet-start:[s3.go.list_objects.session]
	sess := session.Must(session.NewSessionWithOptions(session.Options{
		SharedConfigState: session.SharedConfigEnable,
	}))
	// snippet-end:[s3.go.list_objects.session]

	resp, err := GetObjects(sess, bucket)
	if err != nil {
		fmt.Println("Got error retrieving list of objects:")
		fmt.Println(err)
		return
	}

	// snippet-start:[s3.go.list_objects.print]
	fmt.Println("Objects in " + *bucket + ":")

	for _, item := range resp.Contents {
		fmt.Println("Name:          ", *item.Key)
		fmt.Println("Last modified: ", *item.LastModified)
		fmt.Println("Size:          ", *item.Size)
		fmt.Println("Storage class: ", *item.StorageClass)
		fmt.Println("")
	}

	fmt.Println("Found", len(resp.Contents), "items in bucket", bucket)
	fmt.Println("")
	// snippet-end:[s3.go.list_objects.print]
}

// snippet-end:[s3.go.list_objects]
