<?php
namespace app\components\validators;

use yii\validators\Validator;

class ColorValidator extends Validator
{
    const COLOR_PATTERN = '/^([\da-f]{3}){1,2}$/i';

    public function validateAttribute($model, $attribute)
    {
        $model->{$attribute} = strtoupper($model->{$attribute});

        if (!preg_match(self::COLOR_PATTERN, $model->{$attribute})) {
            $model->addError($attribute, 'Invalid color value.');
        }
    }
}