<?php

function smarty_function_insert_external_feed($params, &$smarty)
{
    if (empty($params['url']) || empty($params['count'])) {
        throw new InvalidArgumentException('Missing required parameter \'url\' or \'count\'');
    }

    $default = [
        'template' => 'block.external_feed.rss.tpl',
        'cache' => 1,
        'type' => 'rss',
        'ttl' => 7200,
        'cache_key' => function ($params) {
            return ['insert_external_feed', $params['template'], $params['type'], $params['url'], $params['count']];
        },
    ];

    $params = array_merge($default, $params);

    $params['get_data_function'] = function (&$params) {
        $feed = simplexml_load_file($params['url'], null, LIBXML_NOCDATA);
        if ($feed === false) {
            $params['ttl'] = 5;
        }
        $params['items'] = [];
        switch ($params['type']) {
            case 'rss':
                foreach ($feed->channel->item as $item) {
                    $params['items'][] = xml2array($item);
                }
                break;
            case 'atom':
                foreach ($feed->entry as $item) {
                    $params['items'][] = xml2array($item);
                }
                break;
            case 'heureka_review':
                foreach ($feed->review as $item) {
                    $params['items'][] = xml2array($item);
                }
                break;
            default:
                throw new InvalidArgumentException('Type \''.$params['type'].'\' is not supported');
        }

        $params['items'] = array_slice($params['items'], 0, $params['count']);
    };

    if (!empty($params['template'])) {
        $smarty->loadPlugin('Smarty_function_include_cached');
        smarty_function_include_cached_optional($params, $smarty);
    }

    if (!empty($params['assign'])) {
        if (empty($params['template'])) {
            $params['get_data_function']($params);
        }

        $smarty->assign($params['assign'], $params);
    }

    return null;
}

function xml2array($xmlObject, $out = [])
{
    foreach ((array) $xmlObject as $index => $node) {
        $out[$index] = (is_object($node) || is_array($node)) ? xml2array($node) : (string) $node;
    }

    if (is_object($xmlObject)) {
        foreach ($xmlObject->attributes() as $name => $attribute) {
            $out["@{$name}"] = (string) $attribute;
        }

        foreach ($xmlObject->getDocNamespaces() as $namespace) {
            foreach ($xmlObject->children($namespace) as $index => $node) {
                $out[$index] = (is_object($node) || is_array($node)) ? xml2array($node) : (string) $node;
            }

            foreach ($xmlObject->attributes($namespace) as $name => $attribute) {
                $out["@{$name}"] = (string) $attribute;
            }
        }
    }

    foreach ($out as $key => $item) {
        if (is_array($item) && count($item) === 1 && key($item) == 0) {
            $out[$key] = reset($item);
        }
    }

    return $out;
}