add & moved to validations folder; del validator/v10

internal/validation/DriversLicence_validation.go

@@ -0,0 +1,38 @@
+package validation
+
+import (
+	"strconv"
+
+	"github.com/go-playground/validator/v10"
+)
+
+func ValidateDriversLicence(fl validator.FieldLevel) bool {
+	fieldValue := fl.Field().String()
+	if len(fieldValue) != 11 {
+		return false
+	}
+
+	id, tenthChar := string(fieldValue[:9]), string(fieldValue[9])
+
+	if tenthChar == "X" {
+		tenthChar = "10"
+	}
+	tenthValue, _ := strconv.ParseInt(tenthChar, 10, 8)
+
+	// for readability
+	weights := []int{9, 8, 7, 6, 5, 4, 3, 2, 1}
+	sum := 0
+
+	for i := 0; i < 9; i++ {
+		char := string(id[i])
+		value, _ := strconv.ParseInt(char, 36, 64)
+		sum += int(value) * weights[i]
+	}
+
+	calcCheckDigit := sum % 11
+	if calcCheckDigit != int(tenthValue) {
+		return false
+	}
+
+	return true
+}