Regex extract variables from [shortcode]

Question

After migrating some content from WordPress to Drupal, I\'ve got som shortcodes that I need to convert:

String content:

Irre

Answer 1

This is my interpretation, I come from a WordPress background and tried to recreate the setup for a custom php project.

It'll handle things like [PHONE] [PHONE abc="123"] etc

The only thing it falls flat on is the WordPress style [HERE] to [HERE]

Function to build a list of available shortcodes

// Setup the default global variable

function create_shortcode($tag, $function)
{
    global $shortcodes;
    $shortcodes[$tag] = $function;
}

define shortcodes individually, e.g. [IFRAME url="https://www.bbc.co.uk"]:

/**
 * iframe, allows the user to add an iframe to a page with responsive div wrapper
 */
create_shortcode('IFRAME', function($atts) {

    // ... some validation goes here

    // The parameters that can be set in the shortcode
    if (empty($atts['url'])) {
        return false;
    }

    return '
    

      
    
';
});

Then when you want to pass a block of html via the shortcode handling do... handle_shortcodes($some_html_with_shortcodes);

function handle_shortcodes($content)
{

    global $shortcodes;

    // Loop through all shortcodes
    foreach($shortcodes as $key => $function){

        $matches = [];

        // Look for shortcodes, returns an array of ALL matches
        preg_match_all("/\[$key([^_^\]].+?)?\]/", $content, $matches, PREG_UNMATCHED_AS_NULL);

        if (!empty($matches))
        {
            $i = 0;
            $full_shortcode = $matches[0];
            $attributes = $matches[1];

            if (!empty($attributes))
            {
                foreach($attributes as $attribute_string) {

                    // Decode the values (e.g. " to ") 
                    $attribute_string = htmlspecialchars_decode($attribute_string);

                    // Find all the query args, looking for `arg="anything"`
                    preg_match_all('/\w+\=\"(.[^"]+)\"/', $attribute_string, $query_args);

                    $params = [];
                    foreach ($query_args[0] as $d) {

                        // Split the
                        list($att, $val) = explode('=', $d, 2);

                        $params[$att] = trim($val, '"');
                    }

                    $content = str_replace($full_shortcode[$i], $function($params), $content);
                    $i++;
                }
            }
        }
    }
    return $content;
}

I've plucked these examples from working code so hopefully it's readable and doesn't have any extra functions exclusive to our setup.