jidaikobo-shibata/a11yc

<?php
/**
 * A11yc\Validate\Check\AltAttrOfImg
 *
 * @package    part of A11yc
 * @author     Jidaikobo Inc.
 * @license    The MIT License (MIT)
 * @copyright  Jidaikobo Inc.
 * @link       http://www.jidaikobo.com
 */
namespace A11yc\Validate\Check;

use A11yc\Element;
use A11yc\Validate;

class AltAttrOfImg extends Validate
{
    /**
     * alt attr of img
     *
     * @param String $url
     * @return Void
     */
    public static function check($url)
    {
        Validate\Set::log($url, 'alt_attr_of_img', self::$unspec, 1);
        $str = Element\Get::ignoredHtml($url);
        $ms = Element\Get::elementsByRe($str, 'ignores', 'imgs');

        if ( ! $ms[1])
        {
            Validate\Set::log($url, 'alt_attr_of_img', self::$unspec, 4);
            return;
        }
        Validate\Set::log($url, 'alt_attr_of_img', self::$unspec, 0);

        foreach ($ms[0] as $k => $m)
        {
            $tstr = $m;
            Validate\Set::log($url, 'alt_attr_of_img', $tstr, 1);

            // alt_attr_of_img
            $attrs = Element\Get::attributes($m);
            $file = Arr::get($attrs, 'src');
            $file = ! empty($file) ? basename($file) : $file;

            // below here alt attribute has to exist.
            if ( ! array_key_exists('alt', $attrs))
            {
                Validate\Set::error($url, 'alt_attr_of_img', $k, $tstr, $file);
                continue;
            }
            Validate\Set::log($url, 'alt_attr_of_img', $tstr, 2);

            // role presentation
            if (Arr::get($attrs, 'role') == 'presentation') continue;

            // alt_attr_of_blank_only
            Validate\Set::errorAndLog(
                preg_match('/^[ 　]+?$/', $attrs['alt']),
                $url,
                'alt_attr_of_blank_only',
                $k,
                $tstr,
                $file
            );

            // alt_attr_of_empty
            Validate\Set::errorAndLog(
                empty($attrs['alt']),
                $url,
                'alt_attr_of_empty',
                $k,
                $tstr,
                $file
            );
        }

        static::addErrorToHtml($url, 'alt_attr_of_empty', static::$error_ids[$url], 'ignores');
        static::addErrorToHtml($url, 'alt_attr_of_img', static::$error_ids[$url], 'ignores');
        static::addErrorToHtml($url, 'alt_attr_of_blank_only', static::$error_ids[$url], 'ignores');
    }
}