SVG embeding funtions

svg-functions.php

<?
function embed_svg($svg_path, $image_class = '', Array $attributes = array(), $is_abs_path = FALSE)
{
    if (!$is_abs_path)
    {
        $image_path = get_template_directory() . '/static/img/' . trim($svg_path, ' /');
    }
    else
    {
        $image_path = $svg_path;
    }

    if (!is_readable($image_path))
    {
        throw new ErrorException('No image "' . $image_path . '""');
    }

    $attributes_list = array();

    if ($attributes)
    {
        foreach ($attributes AS $key => $value)
        {
            $attributes_list[] = esc_attr($key) . '="' . esc_attr($value) . '"';
        }
    }

    $attributes_list = implode(' ', $attributes_list);

    $image = trim(file_get_contents($image_path));

    if (defined('SVG_DEFS_INCLUDED'))
    {
        $matches = array();

        if (preg_match('~<svg[\s\S]+viewBox="([\d\s\.]+?)"~iu', $image, $matches))
        {
            array_shift($matches);

            $svg_path_parts = explode('/', $svg_path);
            array_pop($svg_path_parts);

            $svg_path_parts = array_slice($svg_path_parts, array_search('pages', $svg_path_parts) + 1);

            array_push($svg_path_parts, basename($svg_path, '.svg'));

            $svg_id = implode('--', $svg_path_parts);

            ob_start();
            ?>
            <svg viewBox="<?= esc_attr($matches[0]) ?>" class="<?= esc_attr($image_class) ?>" <?= $attributes_list ?> xmlns="http://www.w3.org/2000/svg">
                <use xlink:href="#<?= esc_attr($svg_id) ?>" width="100%" height="100%"></use>
            </svg>
            <?

            return ob_get_clean();
        }
    }

    if ($image AND ($image_class OR $attributes_list))
    {
        $image = preg_replace('~^<svg\s+xmlns~iu', "<svg class=\"$image_class\" $attributes_list xmlns", $image);
    }

    return $image;
}

function embed_svg_defs($defs_path)
{
    $image_path = trailingslashit(get_template_directory()) . $defs_path;

    if (!is_readable($image_path))
    {
        return;
    }

    $svg = embed_svg($image_path, '', array(), true);

    if (!defined('SVG_DEFS_INCLUDED'))
    {
        define('SVG_DEFS_INCLUDED', true);
    }

    return $svg;
}