utils

var (
	ErrInvalidURL            = errors.New("invalid url")
	ErrInvalidGithubRawURL   = errors.New("invalid github raw url")
	ErrInvalidText           = fmt.Errorf("invalid text format, doesn't conform to regex %s", TextRegex)
	ErrTextTooLong           = errors.New("text should be less than 500 characters")
	ErrEmptyText             = errors.New("text is empty")
	ErrInvalidImageExtension = errors.New(
		"invalid image extension. only " + strings.Join(ImageExtensions, ",") + " is supported",
	)
	ErrInvalidImageMimeType     = errors.New("invalid image mime-type. only png is supported")
	ErrInvalidURLLength         = errors.New("url length should be no larger than 1024 character")
	ErrURLPointingToLocalServer = errors.New("url should not point to local server")
	ErrEmptyURL                 = errors.New("url is empty")
	ErrInvalidTwitterURLRegex   = errors.New(
		"invalid twitter url, it should be of the format https://twitter.com/<username> or https://x.com/<username>",
	)
	ErrResponseTooLarge = errors.New("response too large, allowed size is 1 MB")
)

var (
	// ImageExtensions List of common image file extensions
	// Only support PNG for now to reduce surface area of image validation
	// We do NOT want to support formats like SVG since they can be used for javascript injection
	// If we get pushback on only supporting png, we can support jpg, jpeg, gif, etc. later
	ImageExtensions = []string{".png"}
)