package validator

import (
	"errors"
	"fmt"
	"mangezmieux-backend/internal/logger"
	"mangezmieux-backend/internal/responses"
	"regexp"
	"strings"

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

var regexpValidatorNamespacePrefix = regexp.MustCompile(`^\w+\.`)

func NewDataValidationAPIError(err error) responses.APIError {
	apiErr := responses.ErrDataValidation
	if err != nil {
		var invalidValidationErrror *validatorLib.InvalidValidationError
		if errors.As(err, &invalidValidationErrror) {
			logger.GetLogger().WithError(invalidValidationErrror).WithField("templateAPIErr", apiErr).Error("InvalidValidationError")
		} else {
			var validationErrors validatorLib.ValidationErrors
			if errors.As(err, &validationErrors) {
				for _, e := range validationErrors {
					reason := e.Tag()
					if _, ok := CustomValidators[e.Tag()]; ok {
						reason = truncatingSprintf(CustomValidators[e.Tag()].Message, e.Param())
					}

					namespaceWithoutStructName := regexpValidatorNamespacePrefix.ReplaceAllString(e.Namespace(), "")
					fe := responses.FieldError{
						Field:       namespaceWithoutStructName,
						Constraint:  e.Tag(),
						Description: reason,
					}
					apiErr.Details = append(apiErr.Details, fe)
				}
			} else {
				apiErr.Description = err.Error()
			}
		}
	}
	return apiErr
}

// truncatingSprintf is used as fmt.Sprintf but allow to truncate the additional parameters given when there is more parameters than %v in str.
func truncatingSprintf(str string, args ...interface{}) string {
	n := strings.Count(str, "%v")
	return fmt.Sprintf(str, args[:n]...)
}