Factorize function to sort attribute values

[coudot]

Currently a lot of code is done in display.php to sort attribute values:

        # Sort attributes values
        foreach ($entry[0] as $attr => $values) {
            if ( is_array($values) && $values['count'] > 1 ) {

                # Find key in attributes_map
                $attributes_map_filter = array_filter($attributes_map, function($v) use(&$attr) {
                    return $v['attribute'] == "$attr";
                });
                if( count($attributes_map_filter) < 1 )
                {
                    $k = "";
                    error_log("WARN: no key found for attribute $attr in \$attributes_map");
                }
                elseif( count($attributes_map_filter) > 1 )
                {
                    $k = array_key_first($attributes_map_filter);
                    error_log("WARN: multiple keys found for attribute $attr in \$attributes_map, using first one: $k");
                } 
                else
                { 
                    $k = array_key_first($attributes_map_filter);
                }
                if(isset($attributes_map[$k]['sort']))
                {
                    if($attributes_map[$k]['sort'] == "descending" )
                    {
                        # descending sort
                        arsort($values);
                    }
                    else
                    {
                        # ascending sort
                        asort($values);
                    }
                }
                else
                {
                    # if 'sort' param unset: default to ascending sort
                    asort($values);
                }
            }
            if ( isset($values['count']) ) {
                unset($values['count']);
            }
            $entry[0][$attr] = $values;
        }

This should be put in a common function (maybe in ltb-common) so we can use it easily in other pages.

[davidcoutadeur]

It makes sense to put it in ltb-common indeed.