package shared

import (
	"errors"

	"git.entityseven.com/rilaxik/pllist/internal/domain"
)

func UserMessage(err error) string {
	var validation domain.ValidationError
	if errors.As(err, &validation) {
		return validation.Message
	}

	switch {
	case errors.Is(err, domain.ErrNotFound):
		return "Not found or no access."
	case errors.Is(err, domain.ErrForbidden):
		return "You cannot do that."
	case errors.Is(err, domain.ErrConflict):
		return "This changed while you were looking. Try again."
	case errors.Is(err, domain.ErrInvalidInput):
		return "Invalid input."
	case errors.Is(err, ErrBadCallback):
		return "This button is out of date. Use /lists."
	default:
		return "Something went wrong. Try again."
	}
}

// IsExpectedError reports whether an error carries a user-facing explanation
// rather than an internal failure.
func IsExpectedError(err error) bool {
	var validation domain.ValidationError
	if errors.As(err, &validation) {
		return true
	}
	return errors.Is(err, domain.ErrNotFound) ||
		errors.Is(err, domain.ErrForbidden) ||
		errors.Is(err, domain.ErrConflict) ||
		errors.Is(err, domain.ErrInvalidInput) ||
		errors.Is(err, ErrBadCallback)
}