jidaikobo-shibata/a11yc

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

use A11yc\Model;

class Image
{
    /**
     * get images
     *
     * @param String $url
     * @param String $base_uri
     * @param String $target_html
     * @return  Array
     */
    public static function getImages($url, $base_uri = '', $target_html = '')
    {
        $retvals = array();
        $str = empty($target_html) ? Element\Get::ignoredHtml($url) : $target_html;
        $n = 0;

        // at first, get images in a
        list($retvals, $str, $n) = self::imagesInA($n, $str, $retvals);

        // secondary, get areas
        list($retvals, $str, $n) = self::getArea($n, $str, $retvals);

        // get buttons
        list($retvals, $str, $n) = self::getButton($n, $str, $retvals);

        // input and img
        $retvals = self::getInput($n, $str, $retvals);

        // tidy
        foreach ($retvals as $k => $v)
        {
            // src exists
            if (isset($v['attrs']['src']))
            {
                $retvals[$k]['attrs']['src'] = Util::enuniqueUri($v['attrs']['src'], $base_uri);
            }

            // alt exists
            $retvals = self::tidyAlt($k, $v, $retvals);

            // aria-*
            $retvals[$k]['aria'] = array();
            foreach ($retvals[$k]['attrs'] as $kk => $vv)
            {
                if (substr($kk, 0, 5) != 'aria-') continue;
                $retvals[$k]['aria'][$kk] = $vv;
            }
        }

        return $retvals;
    }

    /**
     * imagesInA
     *
     * @param Integer $n
     * @param String $str
     * @param Array $retvals
     * @return  Array
     */
    private static function imagesInA($n, $str, $retvals)
    {
        preg_match_all('/\<a [^\>]+\>.+?\<\/a\>/is', $str, $as);
        foreach ($as[0] as $v)
        {
            if (strpos($v, '<img ') === false) continue;

            // link
            $attrs       = Element\Get::attributes($v);
            $href        = Arr::get($attrs, 'href');
            $aria_hidden = Arr::get($attrs, 'aria-hidden');
            $tabindex    = Arr::get($attrs, 'tabindex');
            $text_in_a   = Util::s(strip_tags($v));

            // plural images can be exist.
            preg_match_all('/\<img[^\>]+\>/is', $v, $ass);

            foreach ($ass[0] as $vv)
            {
                $retvals[$n]['element'] = 'img (a)';
                $retvals[$n]['is_important'] = true;
                $retvals[$n]['href'] = $href;
                $retvals[$n]['aria_hidden'] = $aria_hidden;
                $retvals[$n]['tabindex'] = $tabindex;
                $retvals[$n]['attrs'] = Element\Get::attributes($vv);
                $retvals[$n]['near_text'] = $text_in_a;
                $n++;
            }

            // remove a within images
            $str = str_replace($v, '', $str);
        }

        return array($retvals, $str, $n);
    }

    /**
     * get Area
     *
     * @param Integer $n
     * @param String $str
     * @param Array $retvals
     * @return  Array
     */
    private static function getArea($n, $str, $retvals)
    {
        preg_match_all('/\<area [^\>]+\>/is', $str, $as);
        foreach ($as[0] as $v)
        {
            // link
            $attrs = Element\Get::attributes($v);
            $retvals[$n]['element'] = 'area';
            $retvals[$n]['is_important'] = true;
            $retvals[$n]['href'] = Arr::get($attrs, 'href');
            $retvals[$n]['attrs'] = $attrs;
            $n++;

            // remove a within images
            $str = str_replace($v, '', $str);
        }
        return array($retvals, $str, $n);
    }

    /**
     * get Button
     *
     * @param Integer $n
     * @param String $str
     * @param Array $retvals
     * @return  Array
     */
    private static function getButton($n, $str, $retvals)
    {
        preg_match_all('/\<button [^\>]+\>.+?\<\/button\>/is', $str, $as);
        foreach ($as[0] as $v)
        {
            if (strpos($v, '<img ') === false) continue;

            // link
            $attrs = Element\Get::attributes($v);
            $aria_hidden = Arr::get($attrs, 'aria-hidden');
            $tabindex = Arr::get($attrs, 'tabindex');

            // plural images can be exist.
            preg_match_all('/\<img[^\>]+\>/is', $v, $ass);
            foreach ($ass[0] as $vv)
            {
                $retvals[$n]['element'] = 'img (button)';
                $retvals[$n]['href'] = null;
                $retvals[$n]['is_important'] = 1;
                $retvals[$n]['aria_hidden'] = $aria_hidden;
                $retvals[$n]['tabindex'] = $tabindex;
                $retvals[$n]['attrs'] = Element\Get::attributes($vv);
                $n++;
            }

            // remove a within images
            $str = str_replace($v, '', $str);
        }
        return array($retvals, $str, $n);
    }

    /**
     * get Input
     *
     * @param Integer $n
     * @param String $str
     * @param Array $retvals
     * @return  Array
     */
    private static function getInput($n, $str, $retvals)
    {
        $force = true;
        $ms = Element\Get::elementsByRe($str, 'ignores', 'tags', $force);

        if ( ! is_array($ms[1])) return $retvals;

        $targets = array('img', 'input');
        foreach ($ms[1] as $k => $v)
        {
            if ( ! in_array($v, $targets)) continue;
            $attrs = Element\Get::attributes($ms[0][$k]);
            if ($v == 'input' && ( ! isset($attrs['type']) || $attrs['type'] != 'image')) continue;

            $retvals[$n]['element'] = $v;
            $retvals[$n]['is_important'] = $v == 'input' ? true : false ;
            $retvals[$n]['href'] = NULL;
            $retvals[$n]['attrs'] = $attrs;
            $n++;
        }
        return $retvals;
    }

    /**
     * tidy alt
     *
     * @param Integer $k
     * @param Array $v
     * @param Array $retvals
     * @return  Array
     */
    private static function tidyAlt($k, $v, $retvals)
    {
        if (isset($v['attrs']['alt']))
        {
            // empty alt
            if (empty($v['attrs']['alt']))
            {
                $retvals[$k]['attrs']['alt'] = '';
            }
            else
            {
                // alt of blank chars
                $alt = str_replace('　', ' ', $v['attrs']['alt']);
                $alt = trim($alt);

                if (empty($alt))
                {
                    $retvals[$k]['attrs']['alt'] = '===a11yc_alt_of_blank_chars===';
                }
                // alt text
                else
                {
                    $retvals[$k]['attrs']['alt'] = $v['attrs']['alt'];
                }
            }

            // newline in attr
            $retvals[$k]['attrs']['newline'] = preg_match("/[\n\r]/is", $v['attrs']['alt']);
        }
        return $retvals;
    }
}