path: root/bootstrap/comments/api/rss.php

<?php namespace HashOver;

// Copyright (C) 2010-2018 Jacob Barkdull
// This file is part of HashOver.
//
// HashOver is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// HashOver is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with HashOver.  If not, see <http://www.gnu.org/licenses/>.


// Tell browser this is XML/RSS
header ('Content-Type: application/xml; charset=utf-8');

// Change to the HashOver directory
chdir (realpath ('../'));

// Do some standard HashOver setup work
require ('backend/nocache-headers.php');
require ('backend/standard-setup.php');

// Autoload class files
spl_autoload_register (function ($uri) {
	$uri = str_replace ('\\', '/', strtolower ($uri));
	$class_name = basename ($uri);
	$error = '"' . $class_name . '.php" file could not be included!';

	if (!@include ('backend/classes/' . $class_name . '.php')) {
		echo '<?xml version="1.0" encoding="UTF-8"?>', PHP_EOL;
		echo '<error>', $error, '</error>';
		exit;
	}
});

function create_rss (&$hashover)
{
	// Shorter variable name
	$thread = $hashover->setup->threadName;

	// Attempt to read page information metadata
	$metadata = $hashover->thread->data->readMeta ('page-info', $thread);

	// Check if metadata read successfully
	if ($metadata !== false) {
		// If so, set page URL blank if it's missing from the metadata
		if (!isset ($metadata['url'])) {
			$metadata['url'] = '';
		}

		// And set page title to "Untitled" if it's missing from the metadata
		if (!isset ($metadata['title'])) {
			$metadata['title'] = $hashover->locale->text['untitled'];
		}
	} else {
		// If not, set default metadata information
		$metadata = array (
			'url' => '',
			'title' => $hashover->locale->text['untitled']
		);
	}

	// Create new DOM document.
	$xml = new \DOMDocument ('1.0', 'UTF-8');
	$xml->preserveWhiteSpace = false;
	$xml->formatOutput = true;

	// Create main RSS element
	$rss = $xml->createElement ('rss');
	$rss->setAttribute ('version', '2.0');
	$rss->setAttribute ('xmlns:dc', 'http://purl.org/dc/elements/1.1/');
	$rss->setAttribute ('xmlns:content', 'http://purl.org/rss/1.0/modules/content/');
	$rss->setAttribute ('xmlns:atom', 'http://www.w3.org/2005/Atom');

	// Display error if the API is disabled
	if ($hashover->setup->apiStatus ('rss') === 'disabled') {
		$title = $xml->createElement ('title');
		$title_value = $xml->createTextNode ('HashOver: RSS API is not enabled.');
		$title->appendChild ($title_value);
		$rss->appendChild ($title);

		$description = $xml->createElement ('description');
		$description_value = $xml->createTextNode ('Error!');
		$description->appendChild ($description_value);
		$rss->appendChild ($description);

		// Add main RSS element to XML
		$xml->appendChild ($rss);

		// Return RSS XML
		exit (str_replace ('  ', "\t", $xml->saveXML ()));
	}

	// Create channel element
	$channel = $xml->createElement ('channel');

	// Create channel title element
	$title = $xml->createElement ('title');
	$title_value = $xml->createTextNode (html_entity_decode ($metadata['title'], ENT_COMPAT, 'UTF-8'));
	$title->appendChild ($title_value);

	// Add channel title to channel element
	$channel->appendChild ($title);

	// Create channel link element
	$link = $xml->createElement ('link');
	$link_value = $xml->createTextNode (html_entity_decode ($metadata['url'], ENT_COMPAT, 'UTF-8'));
	$link->appendChild ($link_value);

	// Add channel link to channel element
	$channel->appendChild ($link);

	// Create channel description element
	$description = $xml->createElement ('description');
	$count_plural = ($hashover->thread->totalCount !== 1);
	$showing_comments_locale = $hashover->locale->text['showing-comments'][$count_plural];
	$count_locale = sprintf ($showing_comments_locale, $hashover->thread->totalCount - 1);
	$description_value = $xml->createTextNode ($count_locale);
	$description->appendChild ($description_value);

	// Add channel description to channel element
	$channel->appendChild ($description);

	// Create channel atom link element
	$atom_link = $xml->createElement ('atom:link');
	$atom_link->setAttribute ('href', 'http://' . $hashover->setup->domain . $_SERVER['PHP_SELF'] . '?url=' . $metadata['url']);
	$atom_link->setAttribute ('rel', 'self');

	// Add channel atom link to channel element
	$channel->appendChild ($atom_link);

	// Create channel language element
	$language = $xml->createElement ('language');
	$language_value = $xml->createTextNode ('en-us');
	$language->appendChild ($language_value);

	// Add channel language to channel element
	$channel->appendChild ($language);

	// Create channel ttl element
	$ttl = $xml->createElement ('ttl');
	$ttl_value = $xml->createTextNode ('40');
	$ttl->appendChild ($ttl_value);

	// Add channel ttl to channel element
	$channel->appendChild ($ttl);

	// Add channel element to main RSS element
	$rss->appendChild ($channel);

	// Parse comments
	function parse_comments (&$metadata, &$comment, &$rss, &$xml, &$hashover)
	{
		// Skip deleted/unmoderated comments
		if (isset ($comment['notice'])) {
			return;
		}

		// Encode HTML entities
		$comment['body'] = htmlentities ($comment['body'], ENT_COMPAT, 'UTF-8', true);

		// Decode HTML entities
		$comment['body'] = html_entity_decode ($comment['body'], ENT_COMPAT, 'UTF-8');

		// Remove [img] tags
		$comment['body'] = preg_replace ('/\[(img|\/img)\]/iS', '', $comment['body']);

		// Parse comment as markdown
		$comment['body'] = $hashover->markdown->parseMarkdown ($comment['body']);

		// Convert <code> tags to <pre> tags
		$comment['body'] = preg_replace ('/(<|<\/)code>/iS', '\\1pre>', $comment['body']);

		// Get name from comment or use configured default
		$name = !empty ($comment['name']) ? $comment['name'] : $hashover->setup->defaultName;

		// Create item element
		$item = $xml->createElement ('item');

		// Generate comment summary item title
		$title = $name . ' : ';
		$single_comment = str_replace (PHP_EOL, ' ', strip_tags ($comment['body']));

		if (mb_strlen ($single_comment) > 40) {
			$title .= mb_substr ($single_comment, 0, 40) . '...';
		} else {
			$title .= $single_comment;
		}

		// Create item title element
		$item_title = $xml->createElement ('title');
		$item_title_value = $xml->createTextNode (html_entity_decode ($title, ENT_COMPAT, 'UTF-8'));
		$item_title->appendChild ($item_title_value);

		// Add item title element to item element
		$item->appendChild ($item_title);

		// Create item name element
		$item_name = $xml->createElement ('name');
		$item_name_value = $xml->createTextNode (html_entity_decode ($name, ENT_COMPAT, 'UTF-8'));
		$item_name->appendChild ($item_name_value);

		// Add item name element to item element
		$item->appendChild ($item_name);

		// Add HTML anchor tag to URLs (hyperlinks)
		$comment['body'] = preg_replace ('/((ftp|http|https):\/\/[a-z0-9-@:%_\+.~#?&\/=]+) {0,}/iS', '<a href="\\1" target="_blank">\\1</a>', $comment['body']);

		// Replace newlines with break tags
		$comment['body'] = str_replace (PHP_EOL, '<br>', $comment['body']);

		// Create item description element
		$item_description = $xml->createElement ('description');
		$item_description_value = $xml->createTextNode ($comment['body']);
		$item_description->appendChild ($item_description_value);

		// Add item description element to item element
		$item->appendChild ($item_description);

		// Create item avatar element
		$item_avatar = $xml->createElement ('avatar');
		$web_root = 'http://' . $hashover->setup->domain . $hashover->setup->httpRoot;
		$item_avatar_value = $xml->createTextNode ($web_root . $comment['avatar']);
		$item_avatar->appendChild ($item_avatar_value);

		// Add item avatar element to item element
		$item->appendChild ($item_avatar);

		if (!empty ($comment['likes'])) {
			// Create item likes element
			$item_likes = $xml->createElement ('likes');
			$item_likes_value = $xml->createTextNode ($comment['likes']);
			$item_likes->appendChild ($item_likes_value);

			// Add item likes element to item element
			$item->appendChild ($item_likes);
		}

		if ($hashover->setup->allowsDislikes === true) {
			if (!empty ($comment['dislikes'])) {
				// Create item dislikes element
				$item_dislikes = $xml->createElement ('dislikes');
				$item_dislikes_value = $xml->createTextNode ($comment['dislikes']);
				$item_dislikes->appendChild ($item_dislikes_value);

				// Add item dislikes element to item element
				$item->appendChild ($item_dislikes);
			}
		}

		// Create item publication date element
		$item_pubDate = $xml->createElement ('pubDate');
		$item_pubDate_value = $xml->createTextNode (date ('D, d M Y H:i:s O', $comment['sort-date']));
		$item_pubDate->appendChild ($item_pubDate_value);

		// Add item pubDate element to item element
		$item->appendChild ($item_pubDate);

		// URL to comment for item guide and link elements
		$item_permalink_url = $metadata['url'] . '#' . $comment['permalink'];

		// Create item guide element
		$item_guid = $xml->createElement ('guid');
		$item_guid_value = $xml->createTextNode ($item_permalink_url);
		$item_guid->appendChild ($item_guid_value);

		// Add item guide element to item element
		$item->appendChild ($item_guid);

		// Create item link element
		$item_link = $xml->createElement ('link');
		$item_link_value = $xml->createTextNode ($item_permalink_url);
		$item_link->appendChild ($item_link_value);

		// Add item link element to item element
		$item->appendChild ($item_link);

		// Add item element to main RSS element
		$rss->appendChild ($item);

		// Recursively parse replies
		if (!empty ($comment['replies'])) {
			foreach ($comment['replies'] as $reply) {
				parse_comments ($metadata, $reply, $rss, $xml, $hashover);
			}
		}
	}

	// Add item element to main RSS element
	foreach ($hashover->comments['primary'] as $comment) {
		parse_comments ($metadata, $comment, $rss, $xml, $hashover);
	}

	// Add main RSS element to XML
	$xml->appendChild ($rss);

	// Return RSS XML
	echo preg_replace_callback ('/^(\s+)/m', function ($spaces) {
		return str_repeat ("\t", strlen ($spaces[1]) / 2);
	}, $xml->saveXML ());

	// Return statistics
	echo $hashover->statistics->executionEnd ();
}

try {
	// Instantiate HashOver class
	$hashover = new \HashOver ('php', 'api');
	$hashover->setup->setPageURL ('request');
	$hashover->setup->collapsesComments = false;
	$hashover->initiate ();
	$hashover->parsePrimary ();

	// Create RSS feed
	create_rss ($hashover);

} catch (\Exception $error) {
	$misc = new Misc ('rss');
	$misc->displayError ($error->getMessage ());
}