package s3

import (
	"context"
	"fmt"
	"os"

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

type S3Service struct {
	client     *s3.Client
	uploader   *manager.Uploader
	bucketName string
}

func NewS3Service() (*S3Service, error) {
	region := os.Getenv("AWS_REGION")
	accessKey := os.Getenv("AWS_ACCESS_KEY_ID")
	secretKey := os.Getenv("AWS_SECRET_ACCESS_KEY")
	bucketName := os.Getenv("S3_BUCKET_NAME")
	endpoint := os.Getenv("S3_ENDPOINT")

	if region == "" || accessKey == "" || secretKey == "" || bucketName == "" {
		return nil, fmt.Errorf("missing required S3 environment variables")
	}

	// Создаем конфигурацию
	cfg, err := config.LoadDefaultConfig(context.TODO(),
		config.WithRegion(region),
		config.WithCredentialsProvider(credentials.NewStaticCredentialsProvider(accessKey, secretKey, "")),
	)
	if err != nil {
		return nil, fmt.Errorf("failed to load AWS config: %w", err)
	}

	// Создаем клиент S3
	var client *s3.Client
	if endpoint != "" {
		// Кастомный endpoint (например, для MinIO)
		client = s3.NewFromConfig(cfg, func(o *s3.Options) {
			o.BaseEndpoint = aws.String(endpoint)
			o.UsePathStyle = true
		})
	} else {
		// Стандартный AWS S3
		client = s3.NewFromConfig(cfg)
	}

	uploader := manager.NewUploader(client)

	return &S3Service{
		client:     client,
		uploader:   uploader,
		bucketName: bucketName,
	}, nil
}

func (s *S3Service) UploadFile(filePath, fileName string) error {
	file, err := os.Open(filePath)
	if err != nil {
		return fmt.Errorf("failed to open file %s: %w", filePath, err)
	}
	defer file.Close()

	_, err = s.uploader.Upload(context.TODO(), &s3.PutObjectInput{
		Bucket: aws.String(s.bucketName),
		Key:    aws.String(fileName),
		Body:   file,
	})
	if err != nil {
		return fmt.Errorf("failed to upload file to S3: %w", err)
	}

	return nil
}