package api

import (
	"fmt"

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

type apiValidationError struct {
	Field string `json:"field"`
	Err   string `json:"error"`
}

func getValidationErrors(ve *validator.ValidationErrors) []apiValidationError {
	errors := make([]apiValidationError, len(*ve))
	for i, fe := range *ve {
		errors[i] = apiValidationError{
			Field: fe.Field(),
			Err:   computeValidationMessage(&fe),
		}
	}
	return errors
}

func computeValidationMessage(fe *validator.FieldError) string {
	tag := (*fe).Tag()
	switch tag {
	case "required":
		return fmt.Sprintf("%s is required.", (*fe).Field())
	case "max":
		return fmt.Sprintf("%s is too long. It should be under %s characters.", (*fe).Field(), (*fe).Param())
	default:
		return fmt.Sprintf("Validation failed for '%s' property.", tag)
	}
}