package main

import (
	"bytes"
	"context"
	"os"
	"path/filepath"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/service/s3"
)

var s3Client *s3.Client

func initS3() error {
	cfg, err := config.LoadDefaultConfig(context.Background(), config.WithRegion("us-east-1"))
	if err != nil {
		return err
	}
	s3Client = s3.NewFromConfig(cfg)
	return nil
}

// iconHashToPath converts a SHA-256 hash to a sharded file path.
func iconHashToPath(iconsDir, hash string) string {
	if len(hash) < 6 {
		return filepath.Join(iconsDir, hash)
	}
	return filepath.Join(iconsDir, hash[:2], hash[2:4], hash[4:6], hash)
}

// readIconFromDisk reads an icon file from the local sharded directory.
func readIconFromDisk(iconsDir, hash string) ([]byte, error) {
	return os.ReadFile(iconHashToPath(iconsDir, hash))
}

// s3UploadBundle uploads a bundle JSON to S3.
func s3UploadBundle(bucket, key string, data []byte) error {
	_, err := s3Client.PutObject(context.Background(), &s3.PutObjectInput{
		Bucket:      aws.String(bucket),
		Key:         aws.String(key),
		Body:        bytes.NewReader(data),
		ContentType: aws.String("application/json"),
	})
	return err
}