var NewList = Class.create();
NewList.prototype = {
    initialize: function (limit) {
        this.limit = limit;
        this.url = '/rss2json/rss2json.cgi';

        new Ajax.Request(
            this.url, {
                method: 'get',
                onComplete: this.insertNews.bind(this)
            }
        );
    },
    insertNews: function(res) {
        var rss = eval( '(' + res.responseText + ')' );

        var news = '';
        if ( rss.item.length ) {
            if ( this.limit && rss.item.length > this.limit ) {
                rss.item.length = this.limit;
            }
            for ( var i = 0; i < rss.item.length; i++ ) {

                news += '<dt>' + rss.item[i].datetime + '</dt>' + "\n";
                if ( rss.item[i].category ) {
                    news += '<dd class="category">【' + rss.item[i].category[0] + '】</dd>';
                }
                news += '<dd><a href="' + rss.item[i].link + '">' + rss.item[i].title + '</a></dd>' + "\n";
            }
        }
        else {
            news += '<dd>情報取得に失敗しました。</dd>';
        }

        $('update').innerHTML = news;
    }
};