package service

import (
	"context"
	"fmt"
	"io"
	"path/filepath"
	"strings"
	"time"

	"netidhub-saas-be/config/config"

	"github.com/gofiber/fiber/v2"
	"github.com/minio/minio-go/v7"
	"github.com/rs/zerolog"
)

// ClientLogoUploadService handles client logo uploads to MinIO
type ClientLogoUploadService struct {
	MinioStorage *config.MinioStorage
	Log          zerolog.Logger
}

// NewClientLogoUploadService creates a new client logo upload service
func NewClientLogoUploadService(minioStorage *config.MinioStorage, log zerolog.Logger) *ClientLogoUploadService {
	return &ClientLogoUploadService{
		MinioStorage: minioStorage,
		Log:          log,
	}
}

// UploadLogo uploads client logo to MinIO and returns the image path
func (s *ClientLogoUploadService) UploadLogo(c *fiber.Ctx, clientId, clientSlug string) (string, string, error) {

	s.Log.Info().
		Str("UploadLogo", clientId).
		Msg("Client upload logo process")

	// Get the uploaded file
	file, err := c.FormFile("logo")
	if err != nil {
		return "", "", fmt.Errorf("failed to get uploaded file: %w", err)
	}

	s.Log.Info().
		Str("Upload Logo File", clientId).Interface("file", file).Msg("Client upload logo files")

	// Validate file type
	if !s.isValidImageType(file.Filename) {
		return "", "", fmt.Errorf("invalid file type. Only jpg, jpeg, png, gif, webp are allowed")
	}

	s.Log.Info().
		Str("Upload Logo File", clientId).Interface("file", s.isValidImageType(file.Filename)).Msg("Client upload logo files")

	// Validate file size (max 5MB)
	const maxSize = 5 * 1024 * 1024 // 5MB
	if file.Size > maxSize {
		return "", "", fmt.Errorf("file size too large. Maximum size is 5MB")
	}

	// Create MinIO connection
	minioClient, err := s.MinioStorage.ConnectMinio()
	if err != nil {
		return "", "", fmt.Errorf("failed to connect to MinIO: %w", err)
	}

	bucketName := s.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	s.Log.Info().
		Str("Upload Logo bucketName", clientId).Interface("bucketName", bucketName).Msg("Client upload logo files")

	// Generate unique filename using client name
	filename := s.generateUniqueFilename(file.Filename, clientSlug)
	objectName := fmt.Sprintf("clients/logos/%s/%s", clientId, filename)

	// Open file
	src, err := file.Open()
	if err != nil {
		return "", "", fmt.Errorf("failed to open uploaded file: %w", err)
	}
	defer src.Close()

	// Upload to MinIO
	_, err = minioClient.PutObject(
		context.Background(),
		bucketName,
		objectName,
		src,
		file.Size,
		minio.PutObjectOptions{
			ContentType: s.getContentType(file.Filename),
		},
	)
	if err != nil {
		return "", "", fmt.Errorf("failed to upload file to MinIO: %w", err)
	}

	s.Log.Info().
		Str("clientId", clientId).
		Str("filename", filename).
		Str("objectName", objectName).
		Int64("fileSize", file.Size).
		Msg("Client logo uploaded successfully")

	return objectName, filename, nil
}

// DeleteLogo deletes client logo from MinIO
func (s *ClientLogoUploadService) DeleteLogo(clientId, imagePath string) error {
	if imagePath == "" {
		return nil // Nothing to delete
	}

	// Create MinIO connection
	minioClient, err := s.MinioStorage.ConnectMinio()
	if err != nil {
		return fmt.Errorf("failed to connect to MinIO: %w", err)
	}

	bucketName := s.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	// Delete from MinIO
	err = minioClient.RemoveObject(context.Background(), bucketName, imagePath, minio.RemoveObjectOptions{})
	if err != nil {
		return fmt.Errorf("failed to delete file from MinIO: %w", err)
	}

	s.Log.Info().
		Str("clientId", clientId).
		Str("imagePath", imagePath).
		Msg("Client logo deleted successfully")

	return nil
}

// GetLogoURL generates a presigned URL for the logo
func (s *ClientLogoUploadService) GetLogoURL(imagePath string, expiry time.Duration) (string, error) {
	if imagePath == "" {
		return "", nil
	}

	// Create MinIO connection
	minioClient, err := s.MinioStorage.ConnectMinio()
	if err != nil {
		return "", fmt.Errorf("failed to connect to MinIO: %w", err)
	}

	bucketName := s.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	// Generate presigned URL
	url, err := minioClient.PresignedGetObject(context.Background(), bucketName, imagePath, expiry, nil)
	if err != nil {
		return "", fmt.Errorf("failed to generate presigned URL: %w", err)
	}

	return url.String(), nil
}

// GetLogoFile retrieves logo file from MinIO and returns file data and content type
func (s *ClientLogoUploadService) GetLogoFile(clientId, filename string) ([]byte, string, error) {
	if filename == "" {
		return nil, "", fmt.Errorf("filename is required")
	}

	// Create MinIO connection
	minioClient, err := s.MinioStorage.ConnectMinio()
	if err != nil {
		return nil, "", fmt.Errorf("failed to connect to MinIO: %w", err)
	}

	bucketName := s.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	objectName := fmt.Sprintf("clients/logos/%s/%s", clientId, filename)
	// Get object from MinIO
	object, err := minioClient.GetObject(context.Background(), bucketName, objectName, minio.GetObjectOptions{})
	if err != nil {
		return nil, "", fmt.Errorf("failed to get object from MinIO: %w", err)
	}
	defer object.Close()

	// Read object data
	data, err := io.ReadAll(object)
	if err != nil {
		return nil, "", fmt.Errorf("failed to read object data: %w", err)
	}

	// Get content type based on file extension
	contentType := s.getContentType(filename)

	s.Log.Info().
		Str("filename", filename).
		Str("contentType", contentType).
		Int("dataSize", len(data)).
		Msg("Logo file retrieved successfully")

	return data, contentType, nil
}

// isValidImageType checks if the file extension is a valid image type
func (s *ClientLogoUploadService) isValidImageType(filename string) bool {
	ext := strings.ToLower(filepath.Ext(filename))
	validExts := []string{".jpg", ".jpeg", ".png", ".gif", ".webp"}

	for _, validExt := range validExts {
		if ext == validExt {
			return true
		}
	}
	return false
}

// generateUniqueFilename generates a unique filename using client name slug + Unix timestamp
func (s *ClientLogoUploadService) generateUniqueFilename(originalFilename, clientSlug string) string {
	ext := filepath.Ext(originalFilename)

	// Get Unix timestamp
	now := time.Now()
	timestamp := now.Unix()

	// Format: clientname_unix_timestamp.ext
	return fmt.Sprintf("%s_%d%s", clientSlug, timestamp, ext)
}

// createSlug converts client name to URL-friendly slug
func (s *ClientLogoUploadService) createSlug(name string) string {
	// Convert to lowercase
	slug := strings.ToLower(name)

	// Replace spaces with underscores
	slug = strings.ReplaceAll(slug, " ", "_")

	// Replace hyphens with underscores
	slug = strings.ReplaceAll(slug, "-", "_")

	// Remove special characters (keep only alphanumeric and underscores)
	var result strings.Builder
	for _, char := range slug {
		if (char >= 'a' && char <= 'z') || (char >= '0' && char <= '9') || char == '_' {
			result.WriteRune(char)
		}
	}

	slug = result.String()

	// Remove multiple consecutive underscores
	for strings.Contains(slug, "__") {
		slug = strings.ReplaceAll(slug, "__", "_")
	}

	// Remove leading/trailing underscores
	slug = strings.Trim(slug, "_")

	// If empty after cleaning, use "client"
	if slug == "" {
		slug = "client"
	}

	return slug
}

// getContentType returns the MIME type based on file extension
func (s *ClientLogoUploadService) getContentType(filename string) string {
	ext := strings.ToLower(filepath.Ext(filename))
	switch ext {
	case ".jpg", ".jpeg":
		return "image/jpeg"
	case ".png":
		return "image/png"
	case ".gif":
		return "image/gif"
	case ".webp":
		return "image/webp"
	default:
		return "application/octet-stream"
	}
}