package validation

import (
	"GoMembership/internal/models"
	"strconv"
	"time"

	"github.com/go-playground/validator/v10"
)

func validateDriverslicence(sl validator.StructLevel) {
	dl := sl.Current().Interface().(models.User).Licence
	if !validateLicence(dl.Number) {
		sl.ReportError(dl.Number, "licence_number", "", "invalid", "")
	}
	if dl.IssuedDate.After(time.Now()) {
		sl.ReportError(dl.IssuedDate, "issued_date", "", "invalid", "")
	}
	if dl.ExpirationDate.Before(time.Now().AddDate(0, 0, 3)) {
		sl.ReportError(dl.ExpirationDate, "expiration_date", "", "too_soon", "")
	}
}

func validateLicence(fieldValue string) bool {
	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
}