package S3

import (
	"context"
	"fmt"
	"strings"
	"time"

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

// Получаем S3 клиент
func getS3Client() (*s3.Client, error) {
	cfg, err := awsConfig.LoadDefaultConfig(context.TODO(),
		awsConfig.WithRegion("ru-central1"),
		awsConfig.WithCredentialsProvider(credentials.NewStaticCredentialsProvider(
			"TJ946G2S1Z5FEI3I7DQQ",
			"C2H2aITHRDpek8H921yhnrINZwDoADsjW3F6HURl",
			"",
		)),
		awsConfig.WithEndpointResolver(aws.EndpointResolverFunc(
			func(service, region string) (aws.Endpoint, error) {
				return aws.Endpoint{
					URL:           "https://s3.regru.cloud",
					SigningRegion: "ru-central1",
					Source:        aws.EndpointSourceCustom,
				}, nil
			},
		)),
	)
	if err != nil {
		return nil, err
	}

	// Создаем клиент с кастомным эндпоинтом
	client := s3.NewFromConfig(cfg, func(o *s3.Options) {
		o.UsePathStyle = true // Важно для некоторых S3 провайдеров
	})

	return client, nil
}

func DeleteFromS3(imageURL string) error {
	const op = "s3.DeleteFromS3"

	parts := strings.SplitN(strings.TrimPrefix(imageURL, "https://s3.regru.cloud/"), "/", 2)
	if len(parts) != 2 {
		return fmt.Errorf("%s: invalid S3 URL format", op)
	}
	bucket := parts[0]
	key := parts[1]

	client, err := getS3Client()
	if err != nil {
		return fmt.Errorf("%s: failed to create S3 client: %w", op, err)
	}

	_, err = client.DeleteObject(context.TODO(), &s3.DeleteObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(key),
	})
	if err != nil {
		return fmt.Errorf("%s: failed to delete object from S3: %w", op, err)
	}

	// Ждем пока объект исчезнет
	waiter := s3.NewObjectNotExistsWaiter(client)
	err = waiter.Wait(context.TODO(), &s3.HeadObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(key),
	}, 30*time.Second)
	if err != nil {
		return fmt.Errorf("%s: failed to wait for object deletion: %w", op, err)
	}

	return nil
}

func GeneratePresignedUploadURL(userID int, filename string) (string, string, error) {
	const op = "s3.GeneratePresignedUploadURL"

	client, err := getS3Client()
	if err != nil {
		return "", "", fmt.Errorf("%s: failed to create S3 client: %w", op, err)
	}

	// Генерируем ключ сразу в конечной папке с уникальным именем
	uniqueKey := fmt.Sprintf("posts/%d/%d_%s", userID, time.Now().UnixNano(), filename)

	presignClient := s3.NewPresignClient(client)

	result, err := presignClient.PresignPutObject(context.TODO(),
		&s3.PutObjectInput{
			Bucket:        aws.String("tailly"),
			Key:           aws.String(uniqueKey),
			ContentLength: aws.Int64(10 * 1024 * 1024),
		},
		s3.WithPresignExpires(15*time.Minute),
	)
	if err != nil {
		return "", "", fmt.Errorf("%s: failed to generate presigned URL: %w", op, err)
	}

	return result.URL, uniqueKey, nil
}