<?php

// (c) Copyright by authors of the Tiki Wiki CMS Groupware Project
//
// All Rights Reserved. See copyright.txt for details and a complete list of authors.
// Licensed under the GNU LESSER GENERAL PUBLIC LICENSE. See license.txt for details.
// $Id$

class Tiki_Formula_Function_ArticleInfo extends Math_Formula_Function
{
    public function evaluate($element)
    {
        global $prefs;

        if (count($element) != 3) {
            $this->error(tra('Expecting three arguments for article-info.'));
        }

        $supported = [ 'rating', 'age-second', 'age-hour', 'age-day', 'age-week', 'age-month', 'view-count' ];
        if (! in_array($element[2], $supported)) {
            $this->error(tra('Unsupported property. Supported properties are: ') . implode(', ', $supported));
        }

        if ($prefs['feature_articles'] != 'y') {
            $this->error(tra('The Articles feature is not activated.'));
        }

        $type = $this->evaluateChild($element[0]);
        $object = $this->evaluateChild($element[1]);
        $property = $element[2];

        if ($type == 'article') {
            $artlib = TikiLib::lib('art');
            $article = $artlib->get_article($object, false);

            if ($property == 'rating') {
                return $article['rating'];
            } elseif ($property == 'view-count') {
                return $article[ 'nbreads' ];
            } elseif (substr($property, 0, 4) == 'age-') {
                $age = time() - $article['publishDate'];

                switch ($property) {
                    case 'age-hour':
                        return max(0, floor($age / 3600));
                    case 'age-day':
                        return max(0, floor($age / (3600 * 24)));
                    case 'age-week':
                        return max(0, floor($age / (3600 * 24 * 7)));
                    case 'age-month':
                        return max(0, floor($age / (3600 * 24 * 30)));
                    default:
                        return max(0, $age);
                }
            }
        } elseif ($type !== 0) {
            $this->error('Only available for articles.');
        }
    }
}