Mecha CMS

Add this snippet to your functions.php file:

Filter::add('content', function($content) use($config) {
    if(strpos($content, '<img ') === false) return $content;
    return preg_replace_callback('#<img\s+.*?(\s*\/?>)#s', function($matches) use($config) {
        extract(Converter::attr($matches[0], array(), array(), false));
        if(isset($attributes['width']) && isset($attributes['height'])) {
            return $matches[0]; // image width and height already defined
        }
        if(isset($attributes['src'])) {
            $src = Converter::url($attributes['src']); // convert relative URL to full URL
            $src = File::path($src); // convert public URL to private file path
            if($path = File::exist($src)) {
                $s = Image::take($path)->inspect(); // inspect local image data
                $attributes['width'] = $s['width']; // set image width
                $attributes['height'] = $s['height']; // set image height
                $out = '<img'; // re-build image HTML
                foreach($attributes as $k => $v) {
                    $out .= ' ' . $k . '="' . $v . '"'; // put attribute(s) data
                }
                return $out . $matches[1]; // output the result!
            }
            return $matches[0]; // external image `src` or invalid image `src` value
        }
        return $matches[0]; // --ibid
    }, $content);
});

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