erm/vendor/github.com/lxn/walk/validators.go

153 lines
3.0 KiB
Go

// Copyright 2011 The Walk Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package walk
import (
"errors"
"fmt"
"math"
"regexp"
)
type Validator interface {
Validate(v interface{}) error
}
type ValidationError struct {
title string
message string
}
func NewValidationError(title, message string) *ValidationError {
return &ValidationError{title: title, message: message}
}
func (ve *ValidationError) Title() string {
return ve.title
}
func (ve *ValidationError) Message() string {
return ve.message
}
func (ve *ValidationError) Error() string {
return fmt.Sprintf("%s - %s", ve.title, ve.message)
}
type RangeValidator struct {
min float64
max float64
}
func NewRangeValidator(min, max float64) (*RangeValidator, error) {
if max < min {
return nil, errors.New("max < min")
}
return &RangeValidator{min: min, max: max}, nil
}
func (rv *RangeValidator) Min() float64 {
return rv.min
}
func (rv *RangeValidator) Max() float64 {
return rv.max
}
func (rv *RangeValidator) Reset(min, max float64) error {
if max < min {
return errors.New("max < min")
}
rv.min, rv.max = min, max
return nil
}
func (rv *RangeValidator) Validate(v interface{}) error {
f64 := v.(float64)
if f64 < rv.min || f64 > rv.max {
var msg string
if math.Abs(rv.min-math.Floor(rv.min)) < math.SmallestNonzeroFloat64 &&
math.Abs(rv.max-math.Floor(rv.max)) < math.SmallestNonzeroFloat64 {
msg = fmt.Sprintf(tr("Please enter a number from %.f to %.f.", "walk"),
rv.min, rv.max)
} else {
msg = fmt.Sprintf(tr("Please enter a number from %s to %s.", "walk"),
FormatFloatGrouped(rv.min, 2), FormatFloatGrouped(rv.max, 2))
}
return NewValidationError(tr("Number out of allowed range", "walk"), msg)
}
return nil
}
type RegexpValidator struct {
re *regexp.Regexp
}
func NewRegexpValidator(pattern string) (*RegexpValidator, error) {
re, err := regexp.Compile(pattern)
if err != nil {
return nil, err
}
return &RegexpValidator{re}, nil
}
func (rv *RegexpValidator) Pattern() string {
return rv.re.String()
}
func (rv *RegexpValidator) Validate(v interface{}) error {
var matched bool
switch val := v.(type) {
case string:
matched = rv.re.MatchString(val)
case []byte:
matched = rv.re.Match(val)
case fmt.Stringer:
matched = rv.re.MatchString(val.String())
default:
panic("Unsupported type")
}
if !matched {
return errors.New(tr("The text does not match the required pattern.", "walk"))
}
return nil
}
type selectionRequiredValidator struct {
}
var selectionRequiredValidatorSingleton Validator = selectionRequiredValidator{}
func SelectionRequiredValidator() Validator {
return selectionRequiredValidatorSingleton
}
func (selectionRequiredValidator) Validate(v interface{}) error {
if v == nil {
// For Widgets like ComboBox nil is passed to indicate "no selection".
return NewValidationError(
tr("Selection Required", "walk"),
tr("Please select one of the provided options.", "walk"))
}
return nil
}