<?php

namespace RSSWriter;

use RSSWriter\FeedInterface;
use RSSWriter\ItemInterface;

interface ChannelInterface
{
    /**
     * Set channel title
     * @param  string $title
     * @return $this
     */
    public function title($title);

    /**
     * Set channel URL
     * @param  string $url
     * @return $this
     */
    public function url($url);

    /**
     * Set channel description
     * @param  string $description
     * @return $this
     */
    public function description($description);

    /**
     * Set ISO639 language code
     *
     * The language the channel is written in. This allows aggregators to group all
     * Italian language sites, for example, on a single page. A list of allowable
     * values for this element, as provided by Netscape, is here. You may also use
     * values defined by the W3C.
     *
     * @param  string $language
     * @return $this
     */
    public function language($language);

    /**
     * Set channel copyright
     * @param  string $copyright
     * @return $this
     */
    public function copyright($copyright);

    /**
     * Set channel published date
     * @param  int   $pubDate Unix timestamp
     * @return $this
     */
    public function pubDate($pubDate);

    /**
     * Set channel last build date
     * @param  int   $lastBuildDate Unix timestamp
     * @return $this
     */
    public function lastBuildDate($lastBuildDate);

    /**
     * Set channel ttl (minutes)
     * @param  int   $ttl
     * @return $this
     */
    public function ttl($ttl);

    /**
     * Add item object
     * @param  \RSSWriter\ItemInterface $item
     * @return $this
     */
    public function addItem(ItemInterface $item);

    /**
     * Append to feed
     * @param  \RSSWriter\FeedInterface $feed
     * @return $this
     */
    public function appendTo(FeedInterface $feed);

    /**
     * Return XML object
     * @return \RSSWriter\SimpleXMLElement
     */
    public function asXML();
}
