Initial

backend/internal/user/validator.go

@@ -0,0 +1,71 @@
+package user
+
+import (
+	"bytes"
+	"image"
+	_ "image/jpeg"
+	_ "image/png"
+	"log/slog"
+	"regexp"
+	"strings"
+)
+
+type Validator struct {
+	emailRegex *regexp.Regexp
+	loginRegex *regexp.Regexp
+}
+
+func NewValidator() (*Validator, error) {
+	emailRegexp := regexp.MustCompile(`^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$`)
+	loginRegex := regexp.MustCompile(`^[a-zA-Z0-9_-]+$`)
+
+	return &Validator{emailRegex: emailRegexp, loginRegex: loginRegex}, nil
+}
+
+func (v *Validator) VerifyEmail(email string) bool {
+	if len(email) < 3 || len(email) > 254 {
+		return false
+	}
+
+	return v.emailRegex.MatchString(email)
+}
+
+func (v *Validator) VerifyLogin(login string) bool {
+	username := strings.TrimSpace(login)
+	if len(username) < 3 || len(username) > 30 {
+		return false
+	}
+	if !v.loginRegex.MatchString(username) {
+		return false
+	}
+
+	return true
+}
+
+func (v *Validator) VerifyPassword(password string) bool {
+	if len(password) < 8 || len(password) > 72 {
+		return false
+	}
+	return true
+}
+
+func (v *Validator) VerifyImage(data []byte) error {
+	r := bytes.NewReader(data)
+	cfg, format, err := image.DecodeConfig(r)
+	if err != nil {
+		slog.Error("decode image config", slog.String("op", "validator.VerifyImage"), slog.Any("error", err))
+		return err
+	}
+
+	switch format {
+	case "jpeg", "png":
+	default:
+		return ErrUnsupportedFormat
+	}
+
+	if cfg.Width > MaxImageWidth || cfg.Height > MaxImageHeight {
+		return ErrExceedDimensions
+	}
+
+	return nil
+}