<?php

/** DomFramework
  * @package domframework
  * @author Dominique Fournier <dominique@fournier38.fr>
  * @license BSD
  */

namespace Domframework;

/** Create the RSS pages for the websites
  * Specification http://www.rssboard.org/rss-specification
  *
  * Will use RssItem class
  */
class Rss
{
    /** The title of the site (MANDATORY)
      */
    private $title;

    /** The link (URL) to the site (MANDATORY)
      */
    private $link;

    /** The Description of the site (MANDATORY)
      */
    private $description;

    /** The language of the feed
      */
    private $language;

    /** The lastBuildDate
      */
    private $lastBuildDate;

    /** The items linked to this RSS
      */
    private $items = array();

    /** Get/Set the value
      * @param string|null $title The title to get/set
      */
    public function title($title = null)
    {
        if ($title === null) {
            return $this->title;
        }
        if (! is_string($title)) {
            throw new \Exception("Title provided to RSS is not a string", 500);
        }
        if ($title === "") {
            $title = null;
        }
        $this->title = $title;
        return $this;
    }

    /** Get/Set the value
      * @param string|null $link The link to get/set
      */
    public function link($link = null)
    {
        if ($link === null) {
            return $this->link;
        }
        if (! is_string($link)) {
            throw new \Exception("Link provided to RSS is not a string", 500);
        }
        $verify = new Verify();
        if (! $verify->is_URL($link)) {
            throw new \Exception("Link provided to RSS is not an URL", 500);
        }
        if ($link === "") {
            $link = null;
        }
        $this->link = $link;
        return $this;
    }

    /** Get/Set the value
      * @param string|null $description The description to get/set
      */
    public function description($description = null)
    {
        if ($description === null) {
            return $this->description;
        }
        if (! is_string($description)) {
            throw new \Exception("Description provided to RSS is not a string", 500);
        }
        if ($description === "") {
            $description = null;
        }
        $this->description = $description;
        return $this;
    }

    /** Get/Set the value
      * @param string|null $language The language to get/set
      */
    public function language($language = null)
    {
        if ($language === null) {
            return $this->language;
        }
        if (! is_string($language)) {
            throw new \Exception("Language provided to RSS is not a string", 500);
        }
        if (
            ! in_array(
                $language,
                array("af", "sq", "eu", "be", "bg", "ca", "zh-cn", "zh-tw", "hr", "cs",
                "da", "nl", "nl-be", "nl-nl", "en", "en-au", "en-bz", "en-ca",
                "en-ie", "en-jm", "en-nz", "en-ph", "en-za", "en-tt", "en-gb",
                "en-us", "en-zw", "et", "fo", "fi", "fr", "fr-be", "fr-ca",
                "fr-fr", "fr-lu", "fr-mc", "fr-ch", "gl", "gd", "de", "de-at",
                "de-de", "de-li", "de-lu", "de-ch", "el", "haw", "hu", "is",
                "in", "ga", "it", "it-it", "it-ch", "ja", "ko", "mk", "no", "pl",
                "pt", "pt-br", "pt-pt", "ro", "ro-mo", "ro-ro", "ru", "ru-mo",
                "ru-ru", "sr", "sk", "sl", "es", "es-ar", "es-bo", "es-cl",
                "es-co", "es-cr", "es-do", "es-ec", "es-sv", "es-gt", "es-hn",
                "es-mx", "es-ni", "es-pa", "es-py", "es-pe", "es-pr", "es-es",
                "es-uy", "es-ve", "sv", "sv-fi", "sv-se", "tr", "uk")
            )
        ) {
            throw new \Exception("Provided language for RSS is not allowed", 500);
        }
        if ($language === "") {
            $language = null;
        }
        $this->language = $language;
        return $this;
    }

    /** Get/Set the value
      * The date must be in the SQL format Y-m-d H:i:s
      * @param string|null $lastBuildDate The lastBuildDate to get/set
      */
    public function lastBuildDate($lastBuildDate = null)
    {
        if ($lastBuildDate === null) {
            return $this->lastBuildDate;
        }
        if (! is_string($lastBuildDate)) {
            throw new \Exception(
                "lastBuildDate provided to RSS is not a string",
                500
            );
        }
        $verify = new Verify();
        if (! $verify->is_datetimeSQL($lastBuildDate)) {
            throw new \Exception(
                "lastBuildDate provided to RSS is not a valid date",
                500
            );
        }
        if ($lastBuildDate === "") {
            $lastBuildDate = null;
        } else {
            $lastBuildDate = Convert::convertDate(
                $lastBuildDate,
                "Y-m-d H:i:s",
                \DateTime::RFC2822
            );
        }
        $this->lastBuildDate = $lastBuildDate;
        return $this;
    }

    /** Add a new item to the RSS
      * Return the new rss object created
      */
    public function addItem()
    {
        $rssitem = new RssItem();
        $this->items[] = $rssitem;
        return $rssitem;
    }

    /** Return the complete RSS in XML format
      * Throw an exception if there is some mandatory fields missing
      */
    public function asXML()
    {
        if ($this->title === null) {
            throw new \Exception("No title is provided for this RSS", 500);
        }
        if ($this->link === null) {
            throw new \Exception("No link is provided for this RSS", 500);
        }
        if ($this->description === null) {
            throw new \Exception("No description is provided for this RSS", 500);
        }
        $xmlstr =
        '<?xml version="1.0"' . '?' . '>' . "\n" .
        '<rss version="2.0">' . "\n" .
        '  <channel>' . "\n" .
        '  </channel>' . "\n" .
        '</rss>';
        $xml = new \SimpleXMLElement($xmlstr);
        $xml->channel->title = $this->title;
        $xml->channel->link = $this->link;
        $xml->channel->description = $this->description;
        if ($this->language !== null) {
            $xml->channel->language = $this->language;
        }
        if ($this->lastBuildDate !== null) {
            $xml->channel->lastBuildDate = $this->lastBuildDate;
        }
        foreach ($this->items as $item) {
            if ($item->title() === null && $item->description() === null) {
                throw new \Exception(
                    "No title nor description defined in the RSS item",
                    500
                );
            }
            $tmpItem = $xml->channel->addChild("item");
            if ($item->title() !== null) {
                $tmpItem->title = $item->title();
            }
            if ($item->link() !== null) {
                $tmpItem->link = $item->link();
            }
            if ($item->description() !== null) {
                $tmpItem->description = $item->description();
            }
            if ($item->author() !== null) {
                $tmpItem->author = $item->author();
            }
            if ($item->comments() !== null) {
                $tmpItem->comments = $item->comments();
            }
            if ($item->guid() !== null) {
                $tmpItem->guid = $item->guid();
            }
            if ($item->pubDate() !== null) {
                $tmpItem->pubDate = $item->pubDate();
            }
        }
        // Ident correctely the xml created in SimpleXML
        $dom = new \DOMDocument('1.0');
        $dom->preserveWhiteSpace = false;
        $dom->formatOutput = true;
        $dom->loadXML($xml->asXML());
        return $dom->saveXML();
    }
}