var NewsItemService = {
    
    addComment : function (newsItem, comment, callback) {
        var xhr = new XMLHttpRequest();
        
        var url = '/index.php?module=XhrNews&action=AddComment';
        
        var params = 'newsitem_id=' + newsItem.getId() + '&content=' + comment.getContent();
        
        xhr.open("POST", url, true);
        
        xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhr.setRequestHeader("Content-length", params.length);
        xhr.setRequestHeader("Connection", "close");
        
        xhr.onreadystatechange = function() {
            if (xhr.readyState == 4 && xhr.status == 200) {
                callback(xhr, newsItem);
            }
        }
        
        xhr.send(params);
    }, 
    deleteComment : function (newsItem, commentId, callback) {
        var xhr = new XMLHttpRequest();
        
        var url = '/index.php?module=XhrNews&action=DeleteComment';
        
        var params = 'comment_id=' + commentId;
        
        xhr.open("POST", url, true);
        
        xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhr.setRequestHeader("Content-length", params.length);
        xhr.setRequestHeader("Connection", "close");
        
        xhr.onreadystatechange = function() {
            if (xhr.readyState == 4 && xhr.status == 200) {
                callback(xhr, newsItem, commentId);
            }
        }
        
        xhr.send(params);
    }, 
    getComments : function (newsItem, callback) {
        var xhr = new XMLHttpRequest();
        
        var url = '/index.php?module=XhrNews&action=GetComments&newsitem_id=' + newsItem.getId();
        
        var params = '';
        
        xhr.open("GET", url, true);
        
        xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhr.setRequestHeader("Content-length", params.length);
        xhr.setRequestHeader("Connection", "close");
        
        xhr.onreadystatechange = function() {
            if (xhr.readyState == 4 && xhr.status == 200) {
                callback(xhr);
            }
        }
        
        xhr.send(params);
    }
}